(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('@lumino/algorithm'), require('@lumino/domutils'), require('@lumino/messaging'), require('@lumino/properties'), require('@lumino/signaling'), require('@lumino/dragdrop'), require('@lumino/coreutils'), require('@lumino/commands'), require('@lumino/virtualdom'), require('@lumino/disposable'), require('@lumino/keyboard')) :
    typeof define === 'function' && define.amd ? define(['exports', '@lumino/algorithm', '@lumino/domutils', '@lumino/messaging', '@lumino/properties', '@lumino/signaling', '@lumino/dragdrop', '@lumino/coreutils', '@lumino/commands', '@lumino/virtualdom', '@lumino/disposable', '@lumino/keyboard'], factory) :
    (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.lumino_widgets = {}, global.lumino_algorithm, global.lumino_domutils, global.lumino_messaging, global.lumino_properties, global.lumino_signaling, global.lumino_dragdrop, global.lumino_coreutils, global.lumino_commands, global.lumino_virtualdom, global.lumino_disposable, global.lumino_keyboard));
}(this, (function (exports, algorithm, domutils, messaging, properties, signaling, dragdrop, coreutils, commands, virtualdom, disposable, keyboard) { 'use strict';

    /*! *****************************************************************************
    Copyright (c) Microsoft Corporation.

    Permission to use, copy, modify, and/or distribute this software for any
    purpose with or without fee is hereby granted.

    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
    REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
    AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
    INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
    LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
    OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
    PERFORMANCE OF THIS SOFTWARE.
    ***************************************************************************** */
    /* global Reflect, Promise */

    var extendStatics = function(d, b) {
        extendStatics = Object.setPrototypeOf ||
            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
            function (d, b) { for (var p in b) if (Object.prototype.hasOwnProperty.call(b, p)) d[p] = b[p]; };
        return extendStatics(d, b);
    };

    function __extends(d, b) {
        if (typeof b !== "function" && b !== null)
            throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
        extendStatics(d, b);
        function __() { this.constructor = d; }
        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
    }

    var __assign = function() {
        __assign = Object.assign || function __assign(t) {
            for (var s, i = 1, n = arguments.length; i < n; i++) {
                s = arguments[i];
                for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p)) t[p] = s[p];
            }
            return t;
        };
        return __assign.apply(this, arguments);
    };

    function __rest(s, e) {
        var t = {};
        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p) && e.indexOf(p) < 0)
            t[p] = s[p];
        if (s != null && typeof Object.getOwnPropertySymbols === "function")
            for (var i = 0, p = Object.getOwnPropertySymbols(s); i < p.length; i++) {
                if (e.indexOf(p[i]) < 0 && Object.prototype.propertyIsEnumerable.call(s, p[i]))
                    t[p[i]] = s[p[i]];
            }
        return t;
    }

    /** @deprecated */
    function __spreadArrays() {
        for (var s = 0, i = 0, il = arguments.length; i < il; i++) s += arguments[i].length;
        for (var r = Array(s), k = 0, i = 0; i < il; i++)
            for (var a = arguments[i], j = 0, jl = a.length; j < jl; j++, k++)
                r[k] = a[j];
        return r;
    }

    // Copyright (c) Jupyter Development Team.
    // Distributed under the terms of the Modified BSD License.
    /*-----------------------------------------------------------------------------
    | Copyright (c) 2014-2017, PhosphorJS Contributors
    |
    | Distributed under the terms of the BSD 3-Clause License.
    |
    | The full license is in the file LICENSE, distributed with this software.
    |----------------------------------------------------------------------------*/
    /**
     * A sizer object for use with the box engine layout functions.
     *
     * #### Notes
     * A box sizer holds the geometry information for an object along an
     * arbitrary layout orientation.
     *
     * For best performance, this class should be treated as a raw data
     * struct. It should not typically be subclassed.
     */
    var BoxSizer = /** @class */ (function () {
        function BoxSizer() {
            /**
             * The preferred size for the sizer.
             *
             * #### Notes
             * The sizer will be given this initial size subject to its size
             * bounds. The sizer will not deviate from this size unless such
             * deviation is required to fit into the available layout space.
             *
             * There is no limit to this value, but it will be clamped to the
             * bounds defined by [[minSize]] and [[maxSize]].
             *
             * The default value is `0`.
             */
            this.sizeHint = 0;
            /**
             * The minimum size of the sizer.
             *
             * #### Notes
             * The sizer will never be sized less than this value, even if
             * it means the sizer will overflow the available layout space.
             *
             * It is assumed that this value lies in the range `[0, Infinity)`
             * and that it is `<=` to [[maxSize]]. Failure to adhere to this
             * constraint will yield undefined results.
             *
             * The default value is `0`.
             */
            this.minSize = 0;
            /**
             * The maximum size of the sizer.
             *
             * #### Notes
             * The sizer will never be sized greater than this value, even if
             * it means the sizer will underflow the available layout space.
             *
             * It is assumed that this value lies in the range `[0, Infinity]`
             * and that it is `>=` to [[minSize]]. Failure to adhere to this
             * constraint will yield undefined results.
             *
             * The default value is `Infinity`.
             */
            this.maxSize = Infinity;
            /**
             * The stretch factor for the sizer.
             *
             * #### Notes
             * This controls how much the sizer stretches relative to its sibling
             * sizers when layout space is distributed. A stretch factor of zero
             * is special and will cause the sizer to only be resized after all
             * other sizers with a stretch factor greater than zero have been
             * resized to their limits.
             *
             * It is assumed that this value is an integer that lies in the range
             * `[0, Infinity)`. Failure to adhere to this constraint will yield
             * undefined results.
             *
             * The default value is `1`.
             */
            this.stretch = 1;
            /**
             * The computed size of the sizer.
             *
             * #### Notes
             * This value is the output of a call to [[boxCalc]]. It represents
             * the computed size for the object along the layout orientation,
             * and will always lie in the range `[minSize, maxSize]`.
             *
             * This value is output only.
             *
             * Changing this value will have no effect.
             */
            this.size = 0;
            /**
             * An internal storage property for the layout algorithm.
             *
             * #### Notes
             * This value is used as temporary storage by the layout algorithm.
             *
             * Changing this value will have no effect.
             */
            this.done = false;
        }
        return BoxSizer;
    }());
    /**
     * The namespace for the box engine layout functions.
     */
    exports.BoxEngine = void 0;
    (function (BoxEngine) {
        /**
         * Calculate the optimal layout sizes for a sequence of box sizers.
         *
         * This distributes the available layout space among the box sizers
         * according to the following algorithm:
         *
         * 1. Initialize the sizers's size to its size hint and compute the
         *    sums for each of size hint, min size, and max size.
         *
         * 2. If the total size hint equals the available space, return.
         *
         * 3. If the available space is less than the total min size, set all
         *    sizers to their min size and return.
         *
         * 4. If the available space is greater than the total max size, set
         *    all sizers to their max size and return.
         *
         * 5. If the layout space is less than the total size hint, distribute
         *    the negative delta as follows:
         *
         *    a. Shrink each sizer with a stretch factor greater than zero by
         *       an amount proportional to the negative space and the sum of
         *       stretch factors. If the sizer reaches its min size, remove
         *       it and its stretch factor from the computation.
         *
         *    b. If after adjusting all stretch sizers there remains negative
         *       space, distribute the space equally among the sizers with a
         *       stretch factor of zero. If a sizer reaches its min size,
         *       remove it from the computation.
         *
         * 6. If the layout space is greater than the total size hint,
         *    distribute the positive delta as follows:
         *
         *    a. Expand each sizer with a stretch factor greater than zero by
         *       an amount proportional to the postive space and the sum of
         *       stretch factors. If the sizer reaches its max size, remove
         *       it and its stretch factor from the computation.
         *
         *    b. If after adjusting all stretch sizers there remains positive
         *       space, distribute the space equally among the sizers with a
         *       stretch factor of zero. If a sizer reaches its max size,
         *       remove it from the computation.
         *
         * 7. return
         *
         * @param sizers - The sizers for a particular layout line.
         *
         * @param space - The available layout space for the sizers.
         *
         * @returns The delta between the provided available space and the
         *   actual consumed space. This value will be zero if the sizers
         *   can be adjusted to fit, negative if the available space is too
         *   small, and positive if the available space is too large.
         *
         * #### Notes
         * The [[size]] of each sizer is updated with the computed size.
         *
         * This function can be called at any time to recompute the layout for
         * an existing sequence of sizers. The previously computed results will
         * have no effect on the new output. It is therefore not necessary to
         * create new sizer objects on each resize event.
         */
        function calc(sizers, space) {
            // Bail early if there is nothing to do.
            var count = sizers.length;
            if (count === 0) {
                return space;
            }
            // Setup the size and stretch counters.
            var totalMin = 0;
            var totalMax = 0;
            var totalSize = 0;
            var totalStretch = 0;
            var stretchCount = 0;
            // Setup the sizers and compute the totals.
            for (var i = 0; i < count; ++i) {
                var sizer = sizers[i];
                var min = sizer.minSize;
                var max = sizer.maxSize;
                var hint = sizer.sizeHint;
                sizer.done = false;
                sizer.size = Math.max(min, Math.min(hint, max));
                totalSize += sizer.size;
                totalMin += min;
                totalMax += max;
                if (sizer.stretch > 0) {
                    totalStretch += sizer.stretch;
                    stretchCount++;
                }
            }
            // If the space is equal to the total size, return early.
            if (space === totalSize) {
                return 0;
            }
            // If the space is less than the total min, minimize each sizer.
            if (space <= totalMin) {
                for (var i = 0; i < count; ++i) {
                    var sizer = sizers[i];
                    sizer.size = sizer.minSize;
                }
                return space - totalMin;
            }
            // If the space is greater than the total max, maximize each sizer.
            if (space >= totalMax) {
                for (var i = 0; i < count; ++i) {
                    var sizer = sizers[i];
                    sizer.size = sizer.maxSize;
                }
                return space - totalMax;
            }
            // The loops below perform sub-pixel precision sizing. A near zero
            // value is used for compares instead of zero to ensure that the
            // loop terminates when the subdivided space is reasonably small.
            var nearZero = 0.01;
            // A counter which is decremented each time a sizer is resized to
            // its limit. This ensures the loops terminate even if there is
            // space remaining to distribute.
            var notDoneCount = count;
            // Distribute negative delta space.
            if (space < totalSize) {
                // Shrink each stretchable sizer by an amount proportional to its
                // stretch factor. If a sizer reaches its min size it's marked as
                // done. The loop progresses in phases where each sizer is given
                // a chance to consume its fair share for the pass, regardless of
                // whether a sizer before it reached its limit. This continues
                // until the stretchable sizers or the free space is exhausted.
                var freeSpace = totalSize - space;
                while (stretchCount > 0 && freeSpace > nearZero) {
                    var distSpace = freeSpace;
                    var distStretch = totalStretch;
                    for (var i = 0; i < count; ++i) {
                        var sizer = sizers[i];
                        if (sizer.done || sizer.stretch === 0) {
                            continue;
                        }
                        var amt = (sizer.stretch * distSpace) / distStretch;
                        if (sizer.size - amt <= sizer.minSize) {
                            freeSpace -= sizer.size - sizer.minSize;
                            totalStretch -= sizer.stretch;
                            sizer.size = sizer.minSize;
                            sizer.done = true;
                            notDoneCount--;
                            stretchCount--;
                        }
                        else {
                            freeSpace -= amt;
                            sizer.size -= amt;
                        }
                    }
                }
                // Distribute any remaining space evenly among the non-stretchable
                // sizers. This progresses in phases in the same manner as above.
                while (notDoneCount > 0 && freeSpace > nearZero) {
                    var amt = freeSpace / notDoneCount;
                    for (var i = 0; i < count; ++i) {
                        var sizer = sizers[i];
                        if (sizer.done) {
                            continue;
                        }
                        if (sizer.size - amt <= sizer.minSize) {
                            freeSpace -= sizer.size - sizer.minSize;
                            sizer.size = sizer.minSize;
                            sizer.done = true;
                            notDoneCount--;
                        }
                        else {
                            freeSpace -= amt;
                            sizer.size -= amt;
                        }
                    }
                }
            }
            // Distribute positive delta space.
            else {
                // Expand each stretchable sizer by an amount proportional to its
                // stretch factor. If a sizer reaches its max size it's marked as
                // done. The loop progresses in phases where each sizer is given
                // a chance to consume its fair share for the pass, regardless of
                // whether a sizer before it reached its limit. This continues
                // until the stretchable sizers or the free space is exhausted.
                var freeSpace = space - totalSize;
                while (stretchCount > 0 && freeSpace > nearZero) {
                    var distSpace = freeSpace;
                    var distStretch = totalStretch;
                    for (var i = 0; i < count; ++i) {
                        var sizer = sizers[i];
                        if (sizer.done || sizer.stretch === 0) {
                            continue;
                        }
                        var amt = (sizer.stretch * distSpace) / distStretch;
                        if (sizer.size + amt >= sizer.maxSize) {
                            freeSpace -= sizer.maxSize - sizer.size;
                            totalStretch -= sizer.stretch;
                            sizer.size = sizer.maxSize;
                            sizer.done = true;
                            notDoneCount--;
                            stretchCount--;
                        }
                        else {
                            freeSpace -= amt;
                            sizer.size += amt;
                        }
                    }
                }
                // Distribute any remaining space evenly among the non-stretchable
                // sizers. This progresses in phases in the same manner as above.
                while (notDoneCount > 0 && freeSpace > nearZero) {
                    var amt = freeSpace / notDoneCount;
                    for (var i = 0; i < count; ++i) {
                        var sizer = sizers[i];
                        if (sizer.done) {
                            continue;
                        }
                        if (sizer.size + amt >= sizer.maxSize) {
                            freeSpace -= sizer.maxSize - sizer.size;
                            sizer.size = sizer.maxSize;
                            sizer.done = true;
                            notDoneCount--;
                        }
                        else {
                            freeSpace -= amt;
                            sizer.size += amt;
                        }
                    }
                }
            }
            // Indicate that the consumed space equals the available space.
            return 0;
        }
        BoxEngine.calc = calc;
        /**
         * Adjust a sizer by a delta and update its neighbors accordingly.
         *
         * @param sizers - The sizers which should be adjusted.
         *
         * @param index - The index of the sizer to grow.
         *
         * @param delta - The amount to adjust the sizer, positive or negative.
         *
         * #### Notes
         * This will adjust the indicated sizer by the specified amount, along
         * with the sizes of the appropriate neighbors, subject to the limits
         * specified by each of the sizers.
         *
         * This is useful when implementing box layouts where the boundaries
         * between the sizers are interactively adjustable by the user.
         */
        function adjust(sizers, index, delta) {
            // Bail early when there is nothing to do.
            if (sizers.length === 0 || delta === 0) {
                return;
            }
            // Dispatch to the proper implementation.
            if (delta > 0) {
                growSizer(sizers, index, delta);
            }
            else {
                shrinkSizer(sizers, index, -delta);
            }
        }
        BoxEngine.adjust = adjust;
        /**
         * Grow a sizer by a positive delta and adjust neighbors.
         */
        function growSizer(sizers, index, delta) {
            // Compute how much the items to the left can expand.
            var growLimit = 0;
            for (var i = 0; i <= index; ++i) {
                var sizer = sizers[i];
                growLimit += sizer.maxSize - sizer.size;
            }
            // Compute how much the items to the right can shrink.
            var shrinkLimit = 0;
            for (var i = index + 1, n = sizers.length; i < n; ++i) {
                var sizer = sizers[i];
                shrinkLimit += sizer.size - sizer.minSize;
            }
            // Clamp the delta adjustment to the limits.
            delta = Math.min(delta, growLimit, shrinkLimit);
            // Grow the sizers to the left by the delta.
            var grow = delta;
            for (var i = index; i >= 0 && grow > 0; --i) {
                var sizer = sizers[i];
                var limit = sizer.maxSize - sizer.size;
                if (limit >= grow) {
                    sizer.sizeHint = sizer.size + grow;
                    grow = 0;
                }
                else {
                    sizer.sizeHint = sizer.size + limit;
                    grow -= limit;
                }
            }
            // Shrink the sizers to the right by the delta.
            var shrink = delta;
            for (var i = index + 1, n = sizers.length; i < n && shrink > 0; ++i) {
                var sizer = sizers[i];
                var limit = sizer.size - sizer.minSize;
                if (limit >= shrink) {
                    sizer.sizeHint = sizer.size - shrink;
                    shrink = 0;
                }
                else {
                    sizer.sizeHint = sizer.size - limit;
                    shrink -= limit;
                }
            }
        }
        /**
         * Shrink a sizer by a positive delta and adjust neighbors.
         */
        function shrinkSizer(sizers, index, delta) {
            // Compute how much the items to the right can expand.
            var growLimit = 0;
            for (var i = index + 1, n = sizers.length; i < n; ++i) {
                var sizer = sizers[i];
                growLimit += sizer.maxSize - sizer.size;
            }
            // Compute how much the items to the left can shrink.
            var shrinkLimit = 0;
            for (var i = 0; i <= index; ++i) {
                var sizer = sizers[i];
                shrinkLimit += sizer.size - sizer.minSize;
            }
            // Clamp the delta adjustment to the limits.
            delta = Math.min(delta, growLimit, shrinkLimit);
            // Grow the sizers to the right by the delta.
            var grow = delta;
            for (var i = index + 1, n = sizers.length; i < n && grow > 0; ++i) {
                var sizer = sizers[i];
                var limit = sizer.maxSize - sizer.size;
                if (limit >= grow) {
                    sizer.sizeHint = sizer.size + grow;
                    grow = 0;
                }
                else {
                    sizer.sizeHint = sizer.size + limit;
                    grow -= limit;
                }
            }
            // Shrink the sizers to the left by the delta.
            var shrink = delta;
            for (var i = index; i >= 0 && shrink > 0; --i) {
                var sizer = sizers[i];
                var limit = sizer.size - sizer.minSize;
                if (limit >= shrink) {
                    sizer.sizeHint = sizer.size - shrink;
                    shrink = 0;
                }
                else {
                    sizer.sizeHint = sizer.size - limit;
                    shrink -= limit;
                }
            }
        }
    })(exports.BoxEngine || (exports.BoxEngine = {}));

    /**
     * An object which holds data related to an object's title.
     *
     * #### Notes
     * A title object is intended to hold the data necessary to display a
     * header for a particular object. A common example is the `TabPanel`,
     * which uses the widget title to populate the tab for a child widget.
     *
     * It is the responsibility of the owner to call the title disposal.
     */
    var Title = /** @class */ (function () {
        /**
         * Construct a new title.
         *
         * @param options - The options for initializing the title.
         */
        function Title(options) {
            this._label = '';
            this._caption = '';
            this._mnemonic = -1;
            this._iconClass = '';
            this._iconLabel = '';
            this._className = '';
            this._closable = false;
            this._changed = new signaling.Signal(this);
            this._isDisposed = false;
            this.owner = options.owner;
            if (options.label !== undefined) {
                this._label = options.label;
            }
            if (options.mnemonic !== undefined) {
                this._mnemonic = options.mnemonic;
            }
            if (options.icon !== undefined) {
                /* <DEPRECATED> */
                if (typeof options.icon === 'string') {
                    // when ._icon is null, the .icon getter will alias .iconClass
                    this._icon = null;
                    this._iconClass = options.icon;
                }
                else {
                    /* </DEPRECATED> */
                    this._icon = options.icon;
                    /* <DEPRECATED> */
                }
                /* </DEPRECATED> */
            }
            else {
                /* <DEPRECATED> */
                // if unset, default to aliasing .iconClass
                this._icon = null;
            }
            /* </DEPRECATED> */
            if (options.iconClass !== undefined) {
                this._iconClass = options.iconClass;
            }
            if (options.iconLabel !== undefined) {
                this._iconLabel = options.iconLabel;
            }
            if (options.iconRenderer !== undefined) {
                this._icon = options.iconRenderer;
            }
            if (options.caption !== undefined) {
                this._caption = options.caption;
            }
            if (options.className !== undefined) {
                this._className = options.className;
            }
            if (options.closable !== undefined) {
                this._closable = options.closable;
            }
            this._dataset = options.dataset || {};
        }
        Object.defineProperty(Title.prototype, "changed", {
            /**
             * A signal emitted when the state of the title changes.
             */
            get: function () {
                return this._changed;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "label", {
            /**
             * Get the label for the title.
             *
             * #### Notes
             * The default value is an empty string.
             */
            get: function () {
                return this._label;
            },
            /**
             * Set the label for the title.
             */
            set: function (value) {
                if (this._label === value) {
                    return;
                }
                this._label = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "mnemonic", {
            /**
             * Get the mnemonic index for the title.
             *
             * #### Notes
             * The default value is `-1`.
             */
            get: function () {
                return this._mnemonic;
            },
            /**
             * Set the mnemonic index for the title.
             */
            set: function (value) {
                if (this._mnemonic === value) {
                    return;
                }
                this._mnemonic = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "icon", {
            /**
             * Get the icon renderer for the title.
             *
             * #### Notes
             * The default value is undefined.
             *
             * DEPRECATED: if set to a string value, the .icon field will function as
             * an alias for the .iconClass field, for backwards compatibility
             */
            get: function () {
                /* <DEPRECATED> */
                if (this._icon === null) {
                    // only alias .iconClass if ._icon has been explicitly nulled
                    return this.iconClass;
                }
                /* </DEPRECATED> */
                return this._icon;
            },
            /**
             * Set the icon renderer for the title.
             *
             * #### Notes
             * A renderer is an object that supplies a render and unrender function.
             *
             * DEPRECATED: if set to a string value, the .icon field will function as
             * an alias for the .iconClass field, for backwards compatibility
             */
            set: function (value /* </DEPRECATED> */) {
                /* <DEPRECATED> */
                if (typeof value === 'string') {
                    // when ._icon is null, the .icon getter will alias .iconClass
                    this._icon = null;
                    this.iconClass = value;
                }
                else {
                    /* </DEPRECATED> */
                    if (this._icon === value) {
                        return;
                    }
                    this._icon = value;
                    this._changed.emit(undefined);
                    /* <DEPRECATED> */
                }
                /* </DEPRECATED> */
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "iconClass", {
            /**
             * Get the icon class name for the title.
             *
             * #### Notes
             * The default value is an empty string.
             */
            get: function () {
                return this._iconClass;
            },
            /**
             * Set the icon class name for the title.
             *
             * #### Notes
             * Multiple class names can be separated with whitespace.
             */
            set: function (value) {
                if (this._iconClass === value) {
                    return;
                }
                this._iconClass = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "iconLabel", {
            /**
             * Get the icon label for the title.
             *
             * #### Notes
             * The default value is an empty string.
             */
            get: function () {
                return this._iconLabel;
            },
            /**
             * Set the icon label for the title.
             *
             * #### Notes
             * Multiple class names can be separated with whitespace.
             */
            set: function (value) {
                if (this._iconLabel === value) {
                    return;
                }
                this._iconLabel = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "iconRenderer", {
            /**
             * @deprecated Use `icon` instead.
             */
            get: function () {
                return this._icon || undefined;
            },
            /**
             * @deprecated Use `icon` instead.
             */
            set: function (value) {
                this.icon = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "caption", {
            /**
             * Get the caption for the title.
             *
             * #### Notes
             * The default value is an empty string.
             */
            get: function () {
                return this._caption;
            },
            /**
             * Set the caption for the title.
             */
            set: function (value) {
                if (this._caption === value) {
                    return;
                }
                this._caption = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "className", {
            /**
             * Get the extra class name for the title.
             *
             * #### Notes
             * The default value is an empty string.
             */
            get: function () {
                return this._className;
            },
            /**
             * Set the extra class name for the title.
             *
             * #### Notes
             * Multiple class names can be separated with whitespace.
             */
            set: function (value) {
                if (this._className === value) {
                    return;
                }
                this._className = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "closable", {
            /**
             * Get the closable state for the title.
             *
             * #### Notes
             * The default value is `false`.
             */
            get: function () {
                return this._closable;
            },
            /**
             * Set the closable state for the title.
             *
             * #### Notes
             * This controls the presence of a close icon when applicable.
             */
            set: function (value) {
                if (this._closable === value) {
                    return;
                }
                this._closable = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "dataset", {
            /**
             * Get the dataset for the title.
             *
             * #### Notes
             * The default value is an empty dataset.
             */
            get: function () {
                return this._dataset;
            },
            /**
             * Set the dataset for the title.
             *
             * #### Notes
             * This controls the data attributes when applicable.
             */
            set: function (value) {
                if (this._dataset === value) {
                    return;
                }
                this._dataset = value;
                this._changed.emit(undefined);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Title.prototype, "isDisposed", {
            /**
             * Test whether the title has been disposed.
             */
            get: function () {
                return this._isDisposed;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Dispose of the resources held by the title.
         *
         * #### Notes
         * It is the responsibility of the owner to call the title disposal.
         */
        Title.prototype.dispose = function () {
            if (this.isDisposed) {
                return;
            }
            this._isDisposed = true;
            signaling.Signal.clearData(this);
        };
        return Title;
    }());

    /**
     * The base class of the lumino widget hierarchy.
     *
     * #### Notes
     * This class will typically be subclassed in order to create a useful
     * widget. However, it can be used directly to host externally created
     * content.
     */
    exports.Widget = /** @class */ (function () {
        /**
         * Construct a new widget.
         *
         * @param options - The options for initializing the widget.
         */
        function Widget(options) {
            if (options === void 0) { options = {}; }
            this._flags = 0;
            this._layout = null;
            this._parent = null;
            this._disposed = new signaling.Signal(this);
            this._hiddenMode = Widget.HiddenMode.Display;
            this.node = Private$j.createNode(options);
            this.addClass('lm-Widget');
            /* <DEPRECATED> */
            this.addClass('p-Widget');
            /* </DEPRECATED> */
        }
        /**
         * Dispose of the widget and its descendant widgets.
         *
         * #### Notes
         * It is unsafe to use the widget after it has been disposed.
         *
         * All calls made to this method after the first are a no-op.
         */
        Widget.prototype.dispose = function () {
            // Do nothing if the widget is already disposed.
            if (this.isDisposed) {
                return;
            }
            // Set the disposed flag and emit the disposed signal.
            this.setFlag(Widget.Flag.IsDisposed);
            this._disposed.emit(undefined);
            // Remove or detach the widget if necessary.
            if (this.parent) {
                this.parent = null;
            }
            else if (this.isAttached) {
                Widget.detach(this);
            }
            // Dispose of the widget layout.
            if (this._layout) {
                this._layout.dispose();
                this._layout = null;
            }
            // Dispose the title
            this.title.dispose();
            // Clear the extra data associated with the widget.
            signaling.Signal.clearData(this);
            messaging.MessageLoop.clearData(this);
            properties.AttachedProperty.clearData(this);
        };
        Object.defineProperty(Widget.prototype, "disposed", {
            /**
             * A signal emitted when the widget is disposed.
             */
            get: function () {
                return this._disposed;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "isDisposed", {
            /**
             * Test whether the widget has been disposed.
             */
            get: function () {
                return this.testFlag(Widget.Flag.IsDisposed);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "isAttached", {
            /**
             * Test whether the widget's node is attached to the DOM.
             */
            get: function () {
                return this.testFlag(Widget.Flag.IsAttached);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "isHidden", {
            /**
             * Test whether the widget is explicitly hidden.
             */
            get: function () {
                return this.testFlag(Widget.Flag.IsHidden);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "isVisible", {
            /**
             * Test whether the widget is visible.
             *
             * #### Notes
             * A widget is visible when it is attached to the DOM, is not
             * explicitly hidden, and has no explicitly hidden ancestors.
             */
            get: function () {
                return this.testFlag(Widget.Flag.IsVisible);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "title", {
            /**
             * The title object for the widget.
             *
             * #### Notes
             * The title object is used by some container widgets when displaying
             * the widget alongside some title, such as a tab panel or side bar.
             *
             * Since not all widgets will use the title, it is created on demand.
             *
             * The `owner` property of the title is set to this widget.
             */
            get: function () {
                return Private$j.titleProperty.get(this);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "id", {
            /**
             * Get the id of the widget's DOM node.
             */
            get: function () {
                return this.node.id;
            },
            /**
             * Set the id of the widget's DOM node.
             */
            set: function (value) {
                this.node.id = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "dataset", {
            /**
             * The dataset for the widget's DOM node.
             */
            get: function () {
                return this.node.dataset;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "hiddenMode", {
            /**
             * Get the method for hiding the widget.
             */
            get: function () {
                return this._hiddenMode;
            },
            /**
             * Set the method for hiding the widget.
             */
            set: function (value) {
                if (this._hiddenMode === value) {
                    return;
                }
                this._hiddenMode = value;
                switch (value) {
                    case Widget.HiddenMode.Display:
                        this.node.style.willChange = 'auto';
                        break;
                    case Widget.HiddenMode.Scale:
                        this.node.style.willChange = 'transform';
                        break;
                }
                if (this.isHidden) {
                    if (value === Widget.HiddenMode.Display) {
                        this.addClass('lm-mod-hidden');
                        /* <DEPRECATED> */
                        this.addClass('p-mod-hidden');
                        /* </DEPRECATED> */
                        this.node.style.transform = '';
                    }
                    else {
                        this.node.style.transform = 'scale(0)';
                        this.removeClass('lm-mod-hidden');
                        /* <DEPRECATED> */
                        this.removeClass('p-mod-hidden');
                        /* </DEPRECATED> */
                    }
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "parent", {
            /**
             * Get the parent of the widget.
             */
            get: function () {
                return this._parent;
            },
            /**
             * Set the parent of the widget.
             *
             * #### Notes
             * Children are typically added to a widget by using a layout, which
             * means user code will not normally set the parent widget directly.
             *
             * The widget will be automatically removed from its old parent.
             *
             * This is a no-op if there is no effective parent change.
             */
            set: function (value) {
                if (this._parent === value) {
                    return;
                }
                if (value && this.contains(value)) {
                    throw new Error('Invalid parent widget.');
                }
                if (this._parent && !this._parent.isDisposed) {
                    var msg = new Widget.ChildMessage('child-removed', this);
                    messaging.MessageLoop.sendMessage(this._parent, msg);
                }
                this._parent = value;
                if (this._parent && !this._parent.isDisposed) {
                    var msg = new Widget.ChildMessage('child-added', this);
                    messaging.MessageLoop.sendMessage(this._parent, msg);
                }
                if (!this.isDisposed) {
                    messaging.MessageLoop.sendMessage(this, Widget.Msg.ParentChanged);
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Widget.prototype, "layout", {
            /**
             * Get the layout for the widget.
             */
            get: function () {
                return this._layout;
            },
            /**
             * Set the layout for the widget.
             *
             * #### Notes
             * The layout is single-use only. It cannot be changed after the
             * first assignment.
             *
             * The layout is disposed automatically when the widget is disposed.
             */
            set: function (value) {
                if (this._layout === value) {
                    return;
                }
                if (this.testFlag(Widget.Flag.DisallowLayout)) {
                    throw new Error('Cannot set widget layout.');
                }
                if (this._layout) {
                    throw new Error('Cannot change widget layout.');
                }
                if (value.parent) {
                    throw new Error('Cannot change layout parent.');
                }
                this._layout = value;
                value.parent = this;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Create an iterator over the widget's children.
         *
         * @returns A new iterator over the children of the widget.
         *
         * #### Notes
         * The widget must have a populated layout in order to have children.
         *
         * If a layout is not installed, the returned iterator will be empty.
         */
        Widget.prototype.children = function () {
            return this._layout ? this._layout.iter() : algorithm.empty();
        };
        /**
         * Test whether a widget is a descendant of this widget.
         *
         * @param widget - The descendant widget of interest.
         *
         * @returns `true` if the widget is a descendant, `false` otherwise.
         */
        Widget.prototype.contains = function (widget) {
            for (var value = widget; value; value = value._parent) {
                if (value === this) {
                    return true;
                }
            }
            return false;
        };
        /**
         * Test whether the widget's DOM node has the given class name.
         *
         * @param name - The class name of interest.
         *
         * @returns `true` if the node has the class, `false` otherwise.
         */
        Widget.prototype.hasClass = function (name) {
            return this.node.classList.contains(name);
        };
        /**
         * Add a class name to the widget's DOM node.
         *
         * @param name - The class name to add to the node.
         *
         * #### Notes
         * If the class name is already added to the node, this is a no-op.
         *
         * The class name must not contain whitespace.
         */
        Widget.prototype.addClass = function (name) {
            this.node.classList.add(name);
        };
        /**
         * Remove a class name from the widget's DOM node.
         *
         * @param name - The class name to remove from the node.
         *
         * #### Notes
         * If the class name is not yet added to the node, this is a no-op.
         *
         * The class name must not contain whitespace.
         */
        Widget.prototype.removeClass = function (name) {
            this.node.classList.remove(name);
        };
        /**
         * Toggle a class name on the widget's DOM node.
         *
         * @param name - The class name to toggle on the node.
         *
         * @param force - Whether to force add the class (`true`) or force
         *   remove the class (`false`). If not provided, the presence of
         *   the class will be toggled from its current state.
         *
         * @returns `true` if the class is now present, `false` otherwise.
         *
         * #### Notes
         * The class name must not contain whitespace.
         */
        Widget.prototype.toggleClass = function (name, force) {
            if (force === true) {
                this.node.classList.add(name);
                return true;
            }
            if (force === false) {
                this.node.classList.remove(name);
                return false;
            }
            return this.node.classList.toggle(name);
        };
        /**
         * Post an `'update-request'` message to the widget.
         *
         * #### Notes
         * This is a simple convenience method for posting the message.
         */
        Widget.prototype.update = function () {
            messaging.MessageLoop.postMessage(this, Widget.Msg.UpdateRequest);
        };
        /**
         * Post a `'fit-request'` message to the widget.
         *
         * #### Notes
         * This is a simple convenience method for posting the message.
         */
        Widget.prototype.fit = function () {
            messaging.MessageLoop.postMessage(this, Widget.Msg.FitRequest);
        };
        /**
         * Post an `'activate-request'` message to the widget.
         *
         * #### Notes
         * This is a simple convenience method for posting the message.
         */
        Widget.prototype.activate = function () {
            messaging.MessageLoop.postMessage(this, Widget.Msg.ActivateRequest);
        };
        /**
         * Send a `'close-request'` message to the widget.
         *
         * #### Notes
         * This is a simple convenience method for sending the message.
         */
        Widget.prototype.close = function () {
            messaging.MessageLoop.sendMessage(this, Widget.Msg.CloseRequest);
        };
        /**
         * Show the widget and make it visible to its parent widget.
         *
         * #### Notes
         * This causes the [[isHidden]] property to be `false`.
         *
         * If the widget is not explicitly hidden, this is a no-op.
         */
        Widget.prototype.show = function () {
            if (!this.testFlag(Widget.Flag.IsHidden)) {
                return;
            }
            if (this.isAttached && (!this.parent || this.parent.isVisible)) {
                messaging.MessageLoop.sendMessage(this, Widget.Msg.BeforeShow);
            }
            this.clearFlag(Widget.Flag.IsHidden);
            this.node.removeAttribute('aria-hidden');
            if (this.hiddenMode === Widget.HiddenMode.Display) {
                this.removeClass('lm-mod-hidden');
                /* <DEPRECATED> */
                this.removeClass('p-mod-hidden');
                /* </DEPRECATED> */
            }
            else {
                this.node.style.transform = '';
            }
            if (this.isAttached && (!this.parent || this.parent.isVisible)) {
                messaging.MessageLoop.sendMessage(this, Widget.Msg.AfterShow);
            }
            if (this.parent) {
                var msg = new Widget.ChildMessage('child-shown', this);
                messaging.MessageLoop.sendMessage(this.parent, msg);
            }
        };
        /**
         * Hide the widget and make it hidden to its parent widget.
         *
         * #### Notes
         * This causes the [[isHidden]] property to be `true`.
         *
         * If the widget is explicitly hidden, this is a no-op.
         */
        Widget.prototype.hide = function () {
            if (this.testFlag(Widget.Flag.IsHidden)) {
                return;
            }
            if (this.isAttached && (!this.parent || this.parent.isVisible)) {
                messaging.MessageLoop.sendMessage(this, Widget.Msg.BeforeHide);
            }
            this.setFlag(Widget.Flag.IsHidden);
            this.node.setAttribute('aria-hidden', 'true');
            if (this.hiddenMode === Widget.HiddenMode.Display) {
                this.addClass('lm-mod-hidden');
                /* <DEPRECATED> */
                this.addClass('p-mod-hidden');
                /* </DEPRECATED> */
            }
            else {
                this.node.style.transform = 'scale(0)';
            }
            if (this.isAttached && (!this.parent || this.parent.isVisible)) {
                messaging.MessageLoop.sendMessage(this, Widget.Msg.AfterHide);
            }
            if (this.parent) {
                var msg = new Widget.ChildMessage('child-hidden', this);
                messaging.MessageLoop.sendMessage(this.parent, msg);
            }
        };
        /**
         * Show or hide the widget according to a boolean value.
         *
         * @param hidden - `true` to hide the widget, or `false` to show it.
         *
         * #### Notes
         * This is a convenience method for `hide()` and `show()`.
         */
        Widget.prototype.setHidden = function (hidden) {
            if (hidden) {
                this.hide();
            }
            else {
                this.show();
            }
        };
        /**
         * Test whether the given widget flag is set.
         *
         * #### Notes
         * This will not typically be called directly by user code.
         */
        Widget.prototype.testFlag = function (flag) {
            return (this._flags & flag) !== 0;
        };
        /**
         * Set the given widget flag.
         *
         * #### Notes
         * This will not typically be called directly by user code.
         */
        Widget.prototype.setFlag = function (flag) {
            this._flags |= flag;
        };
        /**
         * Clear the given widget flag.
         *
         * #### Notes
         * This will not typically be called directly by user code.
         */
        Widget.prototype.clearFlag = function (flag) {
            this._flags &= ~flag;
        };
        /**
         * Process a message sent to the widget.
         *
         * @param msg - The message sent to the widget.
         *
         * #### Notes
         * Subclasses may reimplement this method as needed.
         */
        Widget.prototype.processMessage = function (msg) {
            switch (msg.type) {
                case 'resize':
                    this.notifyLayout(msg);
                    this.onResize(msg);
                    break;
                case 'update-request':
                    this.notifyLayout(msg);
                    this.onUpdateRequest(msg);
                    break;
                case 'fit-request':
                    this.notifyLayout(msg);
                    this.onFitRequest(msg);
                    break;
                case 'before-show':
                    this.notifyLayout(msg);
                    this.onBeforeShow(msg);
                    break;
                case 'after-show':
                    this.setFlag(Widget.Flag.IsVisible);
                    this.notifyLayout(msg);
                    this.onAfterShow(msg);
                    break;
                case 'before-hide':
                    this.notifyLayout(msg);
                    this.onBeforeHide(msg);
                    break;
                case 'after-hide':
                    this.clearFlag(Widget.Flag.IsVisible);
                    this.notifyLayout(msg);
                    this.onAfterHide(msg);
                    break;
                case 'before-attach':
                    this.notifyLayout(msg);
                    this.onBeforeAttach(msg);
                    break;
                case 'after-attach':
                    if (!this.isHidden && (!this.parent || this.parent.isVisible)) {
                        this.setFlag(Widget.Flag.IsVisible);
                    }
                    this.setFlag(Widget.Flag.IsAttached);
                    this.notifyLayout(msg);
                    this.onAfterAttach(msg);
                    break;
                case 'before-detach':
                    this.notifyLayout(msg);
                    this.onBeforeDetach(msg);
                    break;
                case 'after-detach':
                    this.clearFlag(Widget.Flag.IsVisible);
                    this.clearFlag(Widget.Flag.IsAttached);
                    this.notifyLayout(msg);
                    this.onAfterDetach(msg);
                    break;
                case 'activate-request':
                    this.notifyLayout(msg);
                    this.onActivateRequest(msg);
                    break;
                case 'close-request':
                    this.notifyLayout(msg);
                    this.onCloseRequest(msg);
                    break;
                case 'child-added':
                    this.notifyLayout(msg);
                    this.onChildAdded(msg);
                    break;
                case 'child-removed':
                    this.notifyLayout(msg);
                    this.onChildRemoved(msg);
                    break;
                default:
                    this.notifyLayout(msg);
                    break;
            }
        };
        /**
         * Invoke the message processing routine of the widget's layout.
         *
         * @param msg - The message to dispatch to the layout.
         *
         * #### Notes
         * This is a no-op if the widget does not have a layout.
         *
         * This will not typically be called directly by user code.
         */
        Widget.prototype.notifyLayout = function (msg) {
            if (this._layout) {
                this._layout.processParentMessage(msg);
            }
        };
        /**
         * A message handler invoked on a `'close-request'` message.
         *
         * #### Notes
         * The default implementation unparents or detaches the widget.
         */
        Widget.prototype.onCloseRequest = function (msg) {
            if (this.parent) {
                this.parent = null;
            }
            else if (this.isAttached) {
                Widget.detach(this);
            }
        };
        /**
         * A message handler invoked on a `'resize'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onResize = function (msg) { };
        /**
         * A message handler invoked on an `'update-request'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onUpdateRequest = function (msg) { };
        /**
         * A message handler invoked on a `'fit-request'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onFitRequest = function (msg) { };
        /**
         * A message handler invoked on an `'activate-request'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onActivateRequest = function (msg) { };
        /**
         * A message handler invoked on a `'before-show'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onBeforeShow = function (msg) { };
        /**
         * A message handler invoked on an `'after-show'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onAfterShow = function (msg) { };
        /**
         * A message handler invoked on a `'before-hide'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onBeforeHide = function (msg) { };
        /**
         * A message handler invoked on an `'after-hide'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onAfterHide = function (msg) { };
        /**
         * A message handler invoked on a `'before-attach'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onBeforeAttach = function (msg) { };
        /**
         * A message handler invoked on an `'after-attach'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onAfterAttach = function (msg) { };
        /**
         * A message handler invoked on a `'before-detach'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onBeforeDetach = function (msg) { };
        /**
         * A message handler invoked on an `'after-detach'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onAfterDetach = function (msg) { };
        /**
         * A message handler invoked on a `'child-added'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onChildAdded = function (msg) { };
        /**
         * A message handler invoked on a `'child-removed'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Widget.prototype.onChildRemoved = function (msg) { };
        return Widget;
    }());
    /**
     * The namespace for the `Widget` class statics.
     */
    (function (Widget) {
        (function (HiddenMode) {
            /**
             * Set a `lm-mod-hidden` CSS class to hide the widget using `display:none`
             * CSS from the standard Lumino CSS.
             */
            HiddenMode[HiddenMode["Display"] = 0] = "Display";
            /**
             * Hide the widget by setting the `transform` to `'scale(0)'`.
             */
            HiddenMode[HiddenMode["Scale"] = 1] = "Scale";
        })(Widget.HiddenMode || (Widget.HiddenMode = {}));
        (function (Flag) {
            /**
             * The widget has been disposed.
             */
            Flag[Flag["IsDisposed"] = 1] = "IsDisposed";
            /**
             * The widget is attached to the DOM.
             */
            Flag[Flag["IsAttached"] = 2] = "IsAttached";
            /**
             * The widget is hidden.
             */
            Flag[Flag["IsHidden"] = 4] = "IsHidden";
            /**
             * The widget is visible.
             */
            Flag[Flag["IsVisible"] = 8] = "IsVisible";
            /**
             * A layout cannot be set on the widget.
             */
            Flag[Flag["DisallowLayout"] = 16] = "DisallowLayout";
        })(Widget.Flag || (Widget.Flag = {}));
        (function (Msg) {
            /**
             * A singleton `'before-show'` message.
             *
             * #### Notes
             * This message is sent to a widget before it becomes visible.
             *
             * This message is **not** sent when the widget is being attached.
             */
            Msg.BeforeShow = new messaging.Message('before-show');
            /**
             * A singleton `'after-show'` message.
             *
             * #### Notes
             * This message is sent to a widget after it becomes visible.
             *
             * This message is **not** sent when the widget is being attached.
             */
            Msg.AfterShow = new messaging.Message('after-show');
            /**
             * A singleton `'before-hide'` message.
             *
             * #### Notes
             * This message is sent to a widget before it becomes not-visible.
             *
             * This message is **not** sent when the widget is being detached.
             */
            Msg.BeforeHide = new messaging.Message('before-hide');
            /**
             * A singleton `'after-hide'` message.
             *
             * #### Notes
             * This message is sent to a widget after it becomes not-visible.
             *
             * This message is **not** sent when the widget is being detached.
             */
            Msg.AfterHide = new messaging.Message('after-hide');
            /**
             * A singleton `'before-attach'` message.
             *
             * #### Notes
             * This message is sent to a widget before it is attached.
             */
            Msg.BeforeAttach = new messaging.Message('before-attach');
            /**
             * A singleton `'after-attach'` message.
             *
             * #### Notes
             * This message is sent to a widget after it is attached.
             */
            Msg.AfterAttach = new messaging.Message('after-attach');
            /**
             * A singleton `'before-detach'` message.
             *
             * #### Notes
             * This message is sent to a widget before it is detached.
             */
            Msg.BeforeDetach = new messaging.Message('before-detach');
            /**
             * A singleton `'after-detach'` message.
             *
             * #### Notes
             * This message is sent to a widget after it is detached.
             */
            Msg.AfterDetach = new messaging.Message('after-detach');
            /**
             * A singleton `'parent-changed'` message.
             *
             * #### Notes
             * This message is sent to a widget when its parent has changed.
             */
            Msg.ParentChanged = new messaging.Message('parent-changed');
            /**
             * A singleton conflatable `'update-request'` message.
             *
             * #### Notes
             * This message can be dispatched to supporting widgets in order to
             * update their content based on the current widget state. Not all
             * widgets will respond to messages of this type.
             *
             * For widgets with a layout, this message will inform the layout to
             * update the position and size of its child widgets.
             */
            Msg.UpdateRequest = new messaging.ConflatableMessage('update-request');
            /**
             * A singleton conflatable `'fit-request'` message.
             *
             * #### Notes
             * For widgets with a layout, this message will inform the layout to
             * recalculate its size constraints to fit the space requirements of
             * its child widgets, and to update their position and size. Not all
             * layouts will respond to messages of this type.
             */
            Msg.FitRequest = new messaging.ConflatableMessage('fit-request');
            /**
             * A singleton conflatable `'activate-request'` message.
             *
             * #### Notes
             * This message should be dispatched to a widget when it should
             * perform the actions necessary to activate the widget, which
             * may include focusing its node or descendant node.
             */
            Msg.ActivateRequest = new messaging.ConflatableMessage('activate-request');
            /**
             * A singleton conflatable `'close-request'` message.
             *
             * #### Notes
             * This message should be dispatched to a widget when it should close
             * and remove itself from the widget hierarchy.
             */
            Msg.CloseRequest = new messaging.ConflatableMessage('close-request');
        })(Widget.Msg || (Widget.Msg = {}));
        /**
         * A message class for child related messages.
         */
        var ChildMessage = /** @class */ (function (_super) {
            __extends(ChildMessage, _super);
            /**
             * Construct a new child message.
             *
             * @param type - The message type.
             *
             * @param child - The child widget for the message.
             */
            function ChildMessage(type, child) {
                var _this = _super.call(this, type) || this;
                _this.child = child;
                return _this;
            }
            return ChildMessage;
        }(messaging.Message));
        Widget.ChildMessage = ChildMessage;
        /**
         * A message class for `'resize'` messages.
         */
        var ResizeMessage = /** @class */ (function (_super) {
            __extends(ResizeMessage, _super);
            /**
             * Construct a new resize message.
             *
             * @param width - The **offset width** of the widget, or `-1` if
             *   the width is not known.
             *
             * @param height - The **offset height** of the widget, or `-1` if
             *   the height is not known.
             */
            function ResizeMessage(width, height) {
                var _this = _super.call(this, 'resize') || this;
                _this.width = width;
                _this.height = height;
                return _this;
            }
            return ResizeMessage;
        }(messaging.Message));
        Widget.ResizeMessage = ResizeMessage;
        /**
         * The namespace for the `ResizeMessage` class statics.
         */
        (function (ResizeMessage) {
            /**
             * A singleton `'resize'` message with an unknown size.
             */
            ResizeMessage.UnknownSize = new ResizeMessage(-1, -1);
        })(ResizeMessage = Widget.ResizeMessage || (Widget.ResizeMessage = {}));
        /**
         * Attach a widget to a host DOM node.
         *
         * @param widget - The widget of interest.
         *
         * @param host - The DOM node to use as the widget's host.
         *
         * @param ref - The child of `host` to use as the reference element.
         *   If this is provided, the widget will be inserted before this
         *   node in the host. The default is `null`, which will cause the
         *   widget to be added as the last child of the host.
         *
         * #### Notes
         * This will throw an error if the widget is not a root widget, if
         * the widget is already attached, or if the host is not attached
         * to the DOM.
         */
        function attach(widget, host, ref) {
            if (ref === void 0) { ref = null; }
            if (widget.parent) {
                throw new Error('Cannot attach a child widget.');
            }
            if (widget.isAttached || widget.node.isConnected) {
                throw new Error('Widget is already attached.');
            }
            if (!host.isConnected) {
                throw new Error('Host is not attached.');
            }
            messaging.MessageLoop.sendMessage(widget, Widget.Msg.BeforeAttach);
            host.insertBefore(widget.node, ref);
            messaging.MessageLoop.sendMessage(widget, Widget.Msg.AfterAttach);
        }
        Widget.attach = attach;
        /**
         * Detach the widget from its host DOM node.
         *
         * @param widget - The widget of interest.
         *
         * #### Notes
         * This will throw an error if the widget is not a root widget,
         * or if the widget is not attached to the DOM.
         */
        function detach(widget) {
            if (widget.parent) {
                throw new Error('Cannot detach a child widget.');
            }
            if (!widget.isAttached || !widget.node.isConnected) {
                throw new Error('Widget is not attached.');
            }
            messaging.MessageLoop.sendMessage(widget, Widget.Msg.BeforeDetach);
            widget.node.parentNode.removeChild(widget.node);
            messaging.MessageLoop.sendMessage(widget, Widget.Msg.AfterDetach);
        }
        Widget.detach = detach;
    })(exports.Widget || (exports.Widget = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$j;
    (function (Private) {
        /**
         * An attached property for the widget title object.
         */
        Private.titleProperty = new properties.AttachedProperty({
            name: 'title',
            create: function (owner) { return new Title({ owner: owner }); }
        });
        /**
         * Create a DOM node for the given widget options.
         */
        function createNode(options) {
            return options.node || document.createElement(options.tag || 'div');
        }
        Private.createNode = createNode;
    })(Private$j || (Private$j = {}));

    /* eslint-disable @typescript-eslint/no-empty-function */
    /**
     * An abstract base class for creating lumino layouts.
     *
     * #### Notes
     * A layout is used to add widgets to a parent and to arrange those
     * widgets within the parent's DOM node.
     *
     * This class implements the base functionality which is required of
     * nearly all layouts. It must be subclassed in order to be useful.
     *
     * Notably, this class does not define a uniform interface for adding
     * widgets to the layout. A subclass should define that API in a way
     * which is meaningful for its intended use.
     */
    exports.Layout = /** @class */ (function () {
        /**
         * Construct a new layout.
         *
         * @param options - The options for initializing the layout.
         */
        function Layout(options) {
            if (options === void 0) { options = {}; }
            this._disposed = false;
            this._parent = null;
            this._fitPolicy = options.fitPolicy || 'set-min-size';
        }
        /**
         * Dispose of the resources held by the layout.
         *
         * #### Notes
         * This should be reimplemented to clear and dispose of the widgets.
         *
         * All reimplementations should call the superclass method.
         *
         * This method is called automatically when the parent is disposed.
         */
        Layout.prototype.dispose = function () {
            this._parent = null;
            this._disposed = true;
            signaling.Signal.clearData(this);
            properties.AttachedProperty.clearData(this);
        };
        Object.defineProperty(Layout.prototype, "isDisposed", {
            /**
             * Test whether the layout is disposed.
             */
            get: function () {
                return this._disposed;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Layout.prototype, "parent", {
            /**
             * Get the parent widget of the layout.
             */
            get: function () {
                return this._parent;
            },
            /**
             * Set the parent widget of the layout.
             *
             * #### Notes
             * This is set automatically when installing the layout on the parent
             * widget. The parent widget should not be set directly by user code.
             */
            set: function (value) {
                if (this._parent === value) {
                    return;
                }
                if (this._parent) {
                    throw new Error('Cannot change parent widget.');
                }
                if (value.layout !== this) {
                    throw new Error('Invalid parent widget.');
                }
                this._parent = value;
                this.init();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Layout.prototype, "fitPolicy", {
            /**
             * Get the fit policy for the layout.
             *
             * #### Notes
             * The fit policy controls the computed size constraints which are
             * applied to the parent widget by the layout.
             *
             * Some layout implementations may ignore the fit policy.
             */
            get: function () {
                return this._fitPolicy;
            },
            /**
             * Set the fit policy for the layout.
             *
             * #### Notes
             * The fit policy controls the computed size constraints which are
             * applied to the parent widget by the layout.
             *
             * Some layout implementations may ignore the fit policy.
             *
             * Changing the fit policy will clear the current size constraint
             * for the parent widget and then re-fit the parent.
             */
            set: function (value) {
                // Bail if the policy does not change
                if (this._fitPolicy === value) {
                    return;
                }
                // Update the internal policy.
                this._fitPolicy = value;
                // Clear the size constraints and schedule a fit of the parent.
                if (this._parent) {
                    var style = this._parent.node.style;
                    style.minWidth = '';
                    style.minHeight = '';
                    style.maxWidth = '';
                    style.maxHeight = '';
                    this._parent.fit();
                }
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Process a message sent to the parent widget.
         *
         * @param msg - The message sent to the parent widget.
         *
         * #### Notes
         * This method is called by the parent widget to process a message.
         *
         * Subclasses may reimplement this method as needed.
         */
        Layout.prototype.processParentMessage = function (msg) {
            switch (msg.type) {
                case 'resize':
                    this.onResize(msg);
                    break;
                case 'update-request':
                    this.onUpdateRequest(msg);
                    break;
                case 'fit-request':
                    this.onFitRequest(msg);
                    break;
                case 'before-show':
                    this.onBeforeShow(msg);
                    break;
                case 'after-show':
                    this.onAfterShow(msg);
                    break;
                case 'before-hide':
                    this.onBeforeHide(msg);
                    break;
                case 'after-hide':
                    this.onAfterHide(msg);
                    break;
                case 'before-attach':
                    this.onBeforeAttach(msg);
                    break;
                case 'after-attach':
                    this.onAfterAttach(msg);
                    break;
                case 'before-detach':
                    this.onBeforeDetach(msg);
                    break;
                case 'after-detach':
                    this.onAfterDetach(msg);
                    break;
                case 'child-removed':
                    this.onChildRemoved(msg);
                    break;
                case 'child-shown':
                    this.onChildShown(msg);
                    break;
                case 'child-hidden':
                    this.onChildHidden(msg);
                    break;
            }
        };
        /**
         * Perform layout initialization which requires the parent widget.
         *
         * #### Notes
         * This method is invoked immediately after the layout is installed
         * on the parent widget.
         *
         * The default implementation reparents all of the widgets to the
         * layout parent widget.
         *
         * Subclasses should reimplement this method and attach the child
         * widget nodes to the parent widget's node.
         */
        Layout.prototype.init = function () {
            var _this = this;
            algorithm.each(this, function (widget) {
                widget.parent = _this.parent;
            });
        };
        /**
         * A message handler invoked on a `'resize'` message.
         *
         * #### Notes
         * The layout should ensure that its widgets are resized according
         * to the specified layout space, and that they are sent a `'resize'`
         * message if appropriate.
         *
         * The default implementation of this method sends an `UnknownSize`
         * resize message to all widgets.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onResize = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.ResizeMessage.UnknownSize);
            });
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         *
         * #### Notes
         * The layout should ensure that its widgets are resized according
         * to the available layout space, and that they are sent a `'resize'`
         * message if appropriate.
         *
         * The default implementation of this method sends an `UnknownSize`
         * resize message to all widgets.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onUpdateRequest = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.ResizeMessage.UnknownSize);
            });
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message
         * to all widgets. It assumes all widget nodes are attached to the
         * parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onBeforeAttach = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, msg);
            });
        };
        /**
         * A message handler invoked on an `'after-attach'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message
         * to all widgets. It assumes all widget nodes are attached to the
         * parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onAfterAttach = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, msg);
            });
        };
        /**
         * A message handler invoked on a `'before-detach'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message
         * to all widgets. It assumes all widget nodes are attached to the
         * parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onBeforeDetach = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, msg);
            });
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message
         * to all widgets. It assumes all widget nodes are attached to the
         * parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onAfterDetach = function (msg) {
            algorithm.each(this, function (widget) {
                messaging.MessageLoop.sendMessage(widget, msg);
            });
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message to
         * all non-hidden widgets. It assumes all widget nodes are attached
         * to the parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onBeforeShow = function (msg) {
            algorithm.each(this, function (widget) {
                if (!widget.isHidden) {
                    messaging.MessageLoop.sendMessage(widget, msg);
                }
            });
        };
        /**
         * A message handler invoked on an `'after-show'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message to
         * all non-hidden widgets. It assumes all widget nodes are attached
         * to the parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onAfterShow = function (msg) {
            algorithm.each(this, function (widget) {
                if (!widget.isHidden) {
                    messaging.MessageLoop.sendMessage(widget, msg);
                }
            });
        };
        /**
         * A message handler invoked on a `'before-hide'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message to
         * all non-hidden widgets. It assumes all widget nodes are attached
         * to the parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onBeforeHide = function (msg) {
            algorithm.each(this, function (widget) {
                if (!widget.isHidden) {
                    messaging.MessageLoop.sendMessage(widget, msg);
                }
            });
        };
        /**
         * A message handler invoked on an `'after-hide'` message.
         *
         * #### Notes
         * The default implementation of this method forwards the message to
         * all non-hidden widgets. It assumes all widget nodes are attached
         * to the parent widget node.
         *
         * This may be reimplemented by subclasses as needed.
         */
        Layout.prototype.onAfterHide = function (msg) {
            algorithm.each(this, function (widget) {
                if (!widget.isHidden) {
                    messaging.MessageLoop.sendMessage(widget, msg);
                }
            });
        };
        /**
         * A message handler invoked on a `'child-removed'` message.
         *
         * #### Notes
         * This will remove the child widget from the layout.
         *
         * Subclasses should **not** typically reimplement this method.
         */
        Layout.prototype.onChildRemoved = function (msg) {
            this.removeWidget(msg.child);
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Layout.prototype.onFitRequest = function (msg) { };
        /**
         * A message handler invoked on a `'child-shown'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Layout.prototype.onChildShown = function (msg) { };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         *
         * #### Notes
         * The default implementation of this handler is a no-op.
         */
        Layout.prototype.onChildHidden = function (msg) { };
        return Layout;
    }());
    /**
     * The namespace for the `Layout` class statics.
     */
    (function (Layout) {
        /**
         * Get the horizontal alignment for a widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The horizontal alignment for the widget.
         *
         * #### Notes
         * If the layout width allocated to a widget is larger than its max
         * width, the horizontal alignment controls how the widget is placed
         * within the extra horizontal space.
         *
         * If the allocated width is less than the widget's max width, the
         * horizontal alignment has no effect.
         *
         * Some layout implementations may ignore horizontal alignment.
         */
        function getHorizontalAlignment(widget) {
            return Private$i.horizontalAlignmentProperty.get(widget);
        }
        Layout.getHorizontalAlignment = getHorizontalAlignment;
        /**
         * Set the horizontal alignment for a widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the horizontal alignment.
         *
         * #### Notes
         * If the layout width allocated to a widget is larger than its max
         * width, the horizontal alignment controls how the widget is placed
         * within the extra horizontal space.
         *
         * If the allocated width is less than the widget's max width, the
         * horizontal alignment has no effect.
         *
         * Some layout implementations may ignore horizontal alignment.
         *
         * Changing the horizontal alignment will post an `update-request`
         * message to widget's parent, provided the parent has a layout
         * installed.
         */
        function setHorizontalAlignment(widget, value) {
            Private$i.horizontalAlignmentProperty.set(widget, value);
        }
        Layout.setHorizontalAlignment = setHorizontalAlignment;
        /**
         * Get the vertical alignment for a widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The vertical alignment for the widget.
         *
         * #### Notes
         * If the layout height allocated to a widget is larger than its max
         * height, the vertical alignment controls how the widget is placed
         * within the extra vertical space.
         *
         * If the allocated height is less than the widget's max height, the
         * vertical alignment has no effect.
         *
         * Some layout implementations may ignore vertical alignment.
         */
        function getVerticalAlignment(widget) {
            return Private$i.verticalAlignmentProperty.get(widget);
        }
        Layout.getVerticalAlignment = getVerticalAlignment;
        /**
         * Set the vertical alignment for a widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the vertical alignment.
         *
         * #### Notes
         * If the layout height allocated to a widget is larger than its max
         * height, the vertical alignment controls how the widget is placed
         * within the extra vertical space.
         *
         * If the allocated height is less than the widget's max height, the
         * vertical alignment has no effect.
         *
         * Some layout implementations may ignore vertical alignment.
         *
         * Changing the horizontal alignment will post an `update-request`
         * message to widget's parent, provided the parent has a layout
         * installed.
         */
        function setVerticalAlignment(widget, value) {
            Private$i.verticalAlignmentProperty.set(widget, value);
        }
        Layout.setVerticalAlignment = setVerticalAlignment;
    })(exports.Layout || (exports.Layout = {}));
    /**
     * An object which assists in the absolute layout of widgets.
     *
     * #### Notes
     * This class is useful when implementing a layout which arranges its
     * widgets using absolute positioning.
     *
     * This class is used by nearly all of the built-in lumino layouts.
     */
    var LayoutItem = /** @class */ (function () {
        /**
         * Construct a new layout item.
         *
         * @param widget - The widget to be managed by the item.
         *
         * #### Notes
         * The widget will be set to absolute positioning.
         */
        function LayoutItem(widget) {
            this._top = NaN;
            this._left = NaN;
            this._width = NaN;
            this._height = NaN;
            this._minWidth = 0;
            this._minHeight = 0;
            this._maxWidth = Infinity;
            this._maxHeight = Infinity;
            this._disposed = false;
            this.widget = widget;
            this.widget.node.style.position = 'absolute';
        }
        /**
         * Dispose of the the layout item.
         *
         * #### Notes
         * This will reset the positioning of the widget.
         */
        LayoutItem.prototype.dispose = function () {
            // Do nothing if the item is already disposed.
            if (this._disposed) {
                return;
            }
            // Mark the item as disposed.
            this._disposed = true;
            // Reset the widget style.
            var style = this.widget.node.style;
            style.position = '';
            style.top = '';
            style.left = '';
            style.width = '';
            style.height = '';
        };
        Object.defineProperty(LayoutItem.prototype, "minWidth", {
            /**
             * The computed minimum width of the widget.
             *
             * #### Notes
             * This value can be updated by calling the `fit` method.
             */
            get: function () {
                return this._minWidth;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "minHeight", {
            /**
             * The computed minimum height of the widget.
             *
             * #### Notes
             * This value can be updated by calling the `fit` method.
             */
            get: function () {
                return this._minHeight;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "maxWidth", {
            /**
             * The computed maximum width of the widget.
             *
             * #### Notes
             * This value can be updated by calling the `fit` method.
             */
            get: function () {
                return this._maxWidth;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "maxHeight", {
            /**
             * The computed maximum height of the widget.
             *
             * #### Notes
             * This value can be updated by calling the `fit` method.
             */
            get: function () {
                return this._maxHeight;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "isDisposed", {
            /**
             * Whether the layout item is disposed.
             */
            get: function () {
                return this._disposed;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "isHidden", {
            /**
             * Whether the managed widget is hidden.
             */
            get: function () {
                return this.widget.isHidden;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "isVisible", {
            /**
             * Whether the managed widget is visible.
             */
            get: function () {
                return this.widget.isVisible;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(LayoutItem.prototype, "isAttached", {
            /**
             * Whether the managed widget is attached.
             */
            get: function () {
                return this.widget.isAttached;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Update the computed size limits of the managed widget.
         */
        LayoutItem.prototype.fit = function () {
            var limits = domutils.ElementExt.sizeLimits(this.widget.node);
            this._minWidth = limits.minWidth;
            this._minHeight = limits.minHeight;
            this._maxWidth = limits.maxWidth;
            this._maxHeight = limits.maxHeight;
        };
        /**
         * Update the position and size of the managed widget.
         *
         * @param left - The left edge position of the layout box.
         *
         * @param top - The top edge position of the layout box.
         *
         * @param width - The width of the layout box.
         *
         * @param height - The height of the layout box.
         */
        LayoutItem.prototype.update = function (left, top, width, height) {
            // Clamp the size to the computed size limits.
            var clampW = Math.max(this._minWidth, Math.min(width, this._maxWidth));
            var clampH = Math.max(this._minHeight, Math.min(height, this._maxHeight));
            // Adjust the left edge for the horizontal alignment, if needed.
            if (clampW < width) {
                switch (exports.Layout.getHorizontalAlignment(this.widget)) {
                    case 'left':
                        break;
                    case 'center':
                        left += (width - clampW) / 2;
                        break;
                    case 'right':
                        left += width - clampW;
                        break;
                    default:
                        throw 'unreachable';
                }
            }
            // Adjust the top edge for the vertical alignment, if needed.
            if (clampH < height) {
                switch (exports.Layout.getVerticalAlignment(this.widget)) {
                    case 'top':
                        break;
                    case 'center':
                        top += (height - clampH) / 2;
                        break;
                    case 'bottom':
                        top += height - clampH;
                        break;
                    default:
                        throw 'unreachable';
                }
            }
            // Set up the resize variables.
            var resized = false;
            var style = this.widget.node.style;
            // Update the top edge of the widget if needed.
            if (this._top !== top) {
                this._top = top;
                style.top = top + "px";
            }
            // Update the left edge of the widget if needed.
            if (this._left !== left) {
                this._left = left;
                style.left = left + "px";
            }
            // Update the width of the widget if needed.
            if (this._width !== clampW) {
                resized = true;
                this._width = clampW;
                style.width = clampW + "px";
            }
            // Update the height of the widget if needed.
            if (this._height !== clampH) {
                resized = true;
                this._height = clampH;
                style.height = clampH + "px";
            }
            // Send a resize message to the widget if needed.
            if (resized) {
                var msg = new exports.Widget.ResizeMessage(clampW, clampH);
                messaging.MessageLoop.sendMessage(this.widget, msg);
            }
        };
        return LayoutItem;
    }());
    /**
     * The namespace for the module implementation details.
     */
    var Private$i;
    (function (Private) {
        /**
         * The attached property for a widget horizontal alignment.
         */
        Private.horizontalAlignmentProperty = new properties.AttachedProperty({
            name: 'horizontalAlignment',
            create: function () { return 'center'; },
            changed: onAlignmentChanged
        });
        /**
         * The attached property for a widget vertical alignment.
         */
        Private.verticalAlignmentProperty = new properties.AttachedProperty({
            name: 'verticalAlignment',
            create: function () { return 'top'; },
            changed: onAlignmentChanged
        });
        /**
         * The change handler for the attached alignment properties.
         */
        function onAlignmentChanged(child) {
            if (child.parent && child.parent.layout) {
                child.parent.update();
            }
        }
    })(Private$i || (Private$i = {}));

    /**
     * A concrete layout implementation suitable for many use cases.
     *
     * #### Notes
     * This class is suitable as a base class for implementing a variety of
     * layouts, but can also be used directly with standard CSS to layout a
     * collection of widgets.
     */
    var PanelLayout = /** @class */ (function (_super) {
        __extends(PanelLayout, _super);
        function PanelLayout() {
            var _this = _super !== null && _super.apply(this, arguments) || this;
            _this._widgets = [];
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         *
         * #### Notes
         * This will clear and dispose all widgets in the layout.
         *
         * All reimplementations should call the superclass method.
         *
         * This method is called automatically when the parent is disposed.
         */
        PanelLayout.prototype.dispose = function () {
            while (this._widgets.length > 0) {
                this._widgets.pop().dispose();
            }
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(PanelLayout.prototype, "widgets", {
            /**
             * A read-only array of the widgets in the layout.
             */
            get: function () {
                return this._widgets;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Create an iterator over the widgets in the layout.
         *
         * @returns A new iterator over the widgets in the layout.
         */
        PanelLayout.prototype.iter = function () {
            return algorithm.iter(this._widgets);
        };
        /**
         * Add a widget to the end of the layout.
         *
         * @param widget - The widget to add to the layout.
         *
         * #### Notes
         * If the widget is already contained in the layout, it will be moved.
         */
        PanelLayout.prototype.addWidget = function (widget) {
            this.insertWidget(this._widgets.length, widget);
        };
        /**
         * Insert a widget into the layout at the specified index.
         *
         * @param index - The index at which to insert the widget.
         *
         * @param widget - The widget to insert into the layout.
         *
         * #### Notes
         * The index will be clamped to the bounds of the widgets.
         *
         * If the widget is already added to the layout, it will be moved.
         *
         * #### Undefined Behavior
         * An `index` which is non-integral.
         */
        PanelLayout.prototype.insertWidget = function (index, widget) {
            // Remove the widget from its current parent. This is a no-op
            // if the widget's parent is already the layout parent widget.
            widget.parent = this.parent;
            // Look up the current index of the widget.
            var i = this._widgets.indexOf(widget);
            // Clamp the insert index to the array bounds.
            var j = Math.max(0, Math.min(index, this._widgets.length));
            // If the widget is not in the array, insert it.
            if (i === -1) {
                // Insert the widget into the array.
                algorithm.ArrayExt.insert(this._widgets, j, widget);
                // If the layout is parented, attach the widget to the DOM.
                if (this.parent) {
                    this.attachWidget(j, widget);
                }
                // There is nothing more to do.
                return;
            }
            // Otherwise, the widget exists in the array and should be moved.
            // Adjust the index if the location is at the end of the array.
            if (j === this._widgets.length) {
                j--;
            }
            // Bail if there is no effective move.
            if (i === j) {
                return;
            }
            // Move the widget to the new location.
            algorithm.ArrayExt.move(this._widgets, i, j);
            // If the layout is parented, move the widget in the DOM.
            if (this.parent) {
                this.moveWidget(i, j, widget);
            }
        };
        /**
         * Remove a widget from the layout.
         *
         * @param widget - The widget to remove from the layout.
         *
         * #### Notes
         * A widget is automatically removed from the layout when its `parent`
         * is set to `null`. This method should only be invoked directly when
         * removing a widget from a layout which has yet to be installed on a
         * parent widget.
         *
         * This method does *not* modify the widget's `parent`.
         */
        PanelLayout.prototype.removeWidget = function (widget) {
            this.removeWidgetAt(this._widgets.indexOf(widget));
        };
        /**
         * Remove the widget at a given index from the layout.
         *
         * @param index - The index of the widget to remove.
         *
         * #### Notes
         * A widget is automatically removed from the layout when its `parent`
         * is set to `null`. This method should only be invoked directly when
         * removing a widget from a layout which has yet to be installed on a
         * parent widget.
         *
         * This method does *not* modify the widget's `parent`.
         *
         * #### Undefined Behavior
         * An `index` which is non-integral.
         */
        PanelLayout.prototype.removeWidgetAt = function (index) {
            // Remove the widget from the array.
            var widget = algorithm.ArrayExt.removeAt(this._widgets, index);
            // If the layout is parented, detach the widget from the DOM.
            if (widget && this.parent) {
                this.detachWidget(index, widget);
            }
        };
        /**
         * Perform layout initialization which requires the parent widget.
         */
        PanelLayout.prototype.init = function () {
            var _this = this;
            _super.prototype.init.call(this);
            algorithm.each(this, function (widget, index) {
                _this.attachWidget(index, widget);
            });
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This method is called automatically by the panel layout at the
         * appropriate time. It should not be called directly by user code.
         *
         * The default implementation adds the widgets's node to the parent's
         * node at the proper location, and sends the appropriate attach
         * messages to the widget if the parent is attached to the DOM.
         *
         * Subclasses may reimplement this method to control how the widget's
         * node is added to the parent's node.
         */
        PanelLayout.prototype.attachWidget = function (index, widget) {
            // Look up the next sibling reference node.
            var ref = this.parent.node.children[index];
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Insert the widget's node before the sibling.
            this.parent.node.insertBefore(widget.node, ref);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
        };
        /**
         * Move a widget in the parent's DOM node.
         *
         * @param fromIndex - The previous index of the widget in the layout.
         *
         * @param toIndex - The current index of the widget in the layout.
         *
         * @param widget - The widget to move in the parent.
         *
         * #### Notes
         * This method is called automatically by the panel layout at the
         * appropriate time. It should not be called directly by user code.
         *
         * The default implementation moves the widget's node to the proper
         * location in the parent's node and sends the appropriate attach and
         * detach messages to the widget if the parent is attached to the DOM.
         *
         * Subclasses may reimplement this method to control how the widget's
         * node is moved in the parent's node.
         */
        PanelLayout.prototype.moveWidget = function (fromIndex, toIndex, widget) {
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` and  message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Look up the next sibling reference node.
            var ref = this.parent.node.children[toIndex];
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Insert the widget's node before the sibling.
            this.parent.node.insertBefore(widget.node, ref);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param index - The previous index of the widget in the layout.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This method is called automatically by the panel layout at the
         * appropriate time. It should not be called directly by user code.
         *
         * The default implementation removes the widget's node from the
         * parent's node, and sends the appropriate detach messages to the
         * widget if the parent is attached to the DOM.
         *
         * Subclasses may reimplement this method to control how the widget's
         * node is removed from the parent's node.
         */
        PanelLayout.prototype.detachWidget = function (index, widget) {
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
        };
        return PanelLayout;
    }(exports.Layout));

    var Utils;
    (function (Utils) {
        /**
         * Clamp a dimension value to an integer >= 0.
         */
        function clampDimension(value) {
            return Math.max(0, Math.floor(value));
        }
        Utils.clampDimension = clampDimension;
    })(Utils || (Utils = {}));
    var Utils$1 = Utils;

    /**
     * A layout which arranges its widgets into resizable sections.
     */
    exports.SplitLayout = /** @class */ (function (_super) {
        __extends(SplitLayout, _super);
        /**
         * Construct a new split layout.
         *
         * @param options - The options for initializing the layout.
         */
        function SplitLayout(options) {
            var _this = _super.call(this) || this;
            _this.widgetOffset = 0;
            _this._fixed = 0;
            _this._spacing = 4;
            _this._dirty = false;
            _this._hasNormedSizes = false;
            _this._sizers = [];
            _this._items = [];
            _this._handles = [];
            _this._box = null;
            _this._alignment = 'start';
            _this._orientation = 'horizontal';
            _this.renderer = options.renderer;
            if (options.orientation !== undefined) {
                _this._orientation = options.orientation;
            }
            if (options.alignment !== undefined) {
                _this._alignment = options.alignment;
            }
            if (options.spacing !== undefined) {
                _this._spacing = Utils.clampDimension(options.spacing);
            }
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         */
        SplitLayout.prototype.dispose = function () {
            // Dispose of the layout items.
            algorithm.each(this._items, function (item) {
                item.dispose();
            });
            // Clear the layout state.
            this._box = null;
            this._items.length = 0;
            this._sizers.length = 0;
            this._handles.length = 0;
            // Dispose of the rest of the layout.
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(SplitLayout.prototype, "orientation", {
            /**
             * Get the layout orientation for the split layout.
             */
            get: function () {
                return this._orientation;
            },
            /**
             * Set the layout orientation for the split layout.
             */
            set: function (value) {
                if (this._orientation === value) {
                    return;
                }
                this._orientation = value;
                if (!this.parent) {
                    return;
                }
                this.parent.dataset['orientation'] = value;
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitLayout.prototype, "alignment", {
            /**
             * Get the content alignment for the split layout.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand  to fill the
             * entire split layout.
             */
            get: function () {
                return this._alignment;
            },
            /**
             * Set the content alignment for the split layout.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand  to fill the
             * entire split layout.
             */
            set: function (value) {
                if (this._alignment === value) {
                    return;
                }
                this._alignment = value;
                if (!this.parent) {
                    return;
                }
                this.parent.dataset['alignment'] = value;
                this.parent.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitLayout.prototype, "spacing", {
            /**
             * Get the inter-element spacing for the split layout.
             */
            get: function () {
                return this._spacing;
            },
            /**
             * Set the inter-element spacing for the split layout.
             */
            set: function (value) {
                value = Utils.clampDimension(value);
                if (this._spacing === value) {
                    return;
                }
                this._spacing = value;
                if (!this.parent) {
                    return;
                }
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitLayout.prototype, "handles", {
            /**
             * A read-only array of the split handles in the layout.
             */
            get: function () {
                return this._handles;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Get the absolute sizes of the widgets in the layout.
         *
         * @returns A new array of the absolute sizes of the widgets.
         *
         * This method **does not** measure the DOM nodes.
         */
        SplitLayout.prototype.absoluteSizes = function () {
            return this._sizers.map(function (sizer) { return sizer.size; });
        };
        /**
         * Get the relative sizes of the widgets in the layout.
         *
         * @returns A new array of the relative sizes of the widgets.
         *
         * #### Notes
         * The returned sizes reflect the sizes of the widgets normalized
         * relative to their siblings.
         *
         * This method **does not** measure the DOM nodes.
         */
        SplitLayout.prototype.relativeSizes = function () {
            return Private$h.normalize(this._sizers.map(function (sizer) { return sizer.size; }));
        };
        /**
         * Set the relative sizes for the widgets in the layout.
         *
         * @param sizes - The relative sizes for the widgets in the panel.
         * @param update - Update the layout after setting relative sizes.
         * Default is True.
         *
         * #### Notes
         * Extra values are ignored, too few will yield an undefined layout.
         *
         * The actual geometry of the DOM nodes is updated asynchronously.
         */
        SplitLayout.prototype.setRelativeSizes = function (sizes, update) {
            if (update === void 0) { update = true; }
            // Copy the sizes and pad with zeros as needed.
            var n = this._sizers.length;
            var temp = sizes.slice(0, n);
            while (temp.length < n) {
                temp.push(0);
            }
            // Normalize the padded sizes.
            var normed = Private$h.normalize(temp);
            // Apply the normalized sizes to the sizers.
            for (var i = 0; i < n; ++i) {
                var sizer = this._sizers[i];
                sizer.sizeHint = normed[i];
                sizer.size = normed[i];
            }
            // Set the flag indicating the sizes are normalized.
            this._hasNormedSizes = true;
            // Trigger an update of the parent widget.
            if (update && this.parent) {
                this.parent.update();
            }
        };
        /**
         * Move the offset position of a split handle.
         *
         * @param index - The index of the handle of the interest.
         *
         * @param position - The desired offset position of the handle.
         *
         * #### Notes
         * The position is relative to the offset parent.
         *
         * This will move the handle as close as possible to the desired
         * position. The sibling widgets will be adjusted as necessary.
         */
        SplitLayout.prototype.moveHandle = function (index, position) {
            // Bail if the index is invalid or the handle is hidden.
            var handle = this._handles[index];
            if (!handle || handle.classList.contains('lm-mod-hidden')) {
                return;
            }
            // Compute the desired delta movement for the handle.
            var delta;
            if (this._orientation === 'horizontal') {
                delta = position - handle.offsetLeft;
            }
            else {
                delta = position - handle.offsetTop;
            }
            // Bail if there is no handle movement.
            if (delta === 0) {
                return;
            }
            // Prevent widget resizing unless needed.
            for (var _i = 0, _a = this._sizers; _i < _a.length; _i++) {
                var sizer = _a[_i];
                if (sizer.size > 0) {
                    sizer.sizeHint = sizer.size;
                }
            }
            // Adjust the sizers to reflect the handle movement.
            exports.BoxEngine.adjust(this._sizers, index, delta);
            // Update the layout of the widgets.
            if (this.parent) {
                this.parent.update();
            }
        };
        /**
         * Perform layout initialization which requires the parent widget.
         */
        SplitLayout.prototype.init = function () {
            this.parent.dataset['orientation'] = this.orientation;
            this.parent.dataset['alignment'] = this.alignment;
            _super.prototype.init.call(this);
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        SplitLayout.prototype.attachWidget = function (index, widget) {
            // Create the item, handle, and sizer for the new widget.
            var item = new LayoutItem(widget);
            var handle = Private$h.createHandle(this.renderer);
            var average = Private$h.averageSize(this._sizers);
            var sizer = Private$h.createSizer(average);
            // Insert the item, handle, and sizer into the internal arrays.
            algorithm.ArrayExt.insert(this._items, index, item);
            algorithm.ArrayExt.insert(this._sizers, index, sizer);
            algorithm.ArrayExt.insert(this._handles, index, handle);
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget and handle nodes to the parent.
            this.parent.node.appendChild(widget.node);
            this.parent.node.appendChild(handle);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Move a widget in the parent's DOM node.
         *
         * @param fromIndex - The previous index of the widget in the layout.
         *
         * @param toIndex - The current index of the widget in the layout.
         *
         * @param widget - The widget to move in the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        SplitLayout.prototype.moveWidget = function (fromIndex, toIndex, widget) {
            // Move the item, sizer, and handle for the widget.
            algorithm.ArrayExt.move(this._items, fromIndex, toIndex);
            algorithm.ArrayExt.move(this._sizers, fromIndex, toIndex);
            algorithm.ArrayExt.move(this._handles, fromIndex, toIndex);
            // Post a fit request to the parent to show/hide last handle.
            this.parent.fit();
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param index - The previous index of the widget in the layout.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        SplitLayout.prototype.detachWidget = function (index, widget) {
            // Remove the item, handle, and sizer for the widget.
            var item = algorithm.ArrayExt.removeAt(this._items, index);
            var handle = algorithm.ArrayExt.removeAt(this._handles, index);
            algorithm.ArrayExt.removeAt(this._sizers, index);
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget and handle nodes from the parent.
            this.parent.node.removeChild(widget.node);
            this.parent.node.removeChild(handle);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Dispose of the layout item.
            item.dispose();
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         */
        SplitLayout.prototype.onBeforeShow = function (msg) {
            _super.prototype.onBeforeShow.call(this, msg);
            this.parent.update();
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        SplitLayout.prototype.onBeforeAttach = function (msg) {
            _super.prototype.onBeforeAttach.call(this, msg);
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-shown'` message.
         */
        SplitLayout.prototype.onChildShown = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         */
        SplitLayout.prototype.onChildHidden = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'resize'` message.
         */
        SplitLayout.prototype.onResize = function (msg) {
            if (this.parent.isVisible) {
                this._update(msg.width, msg.height);
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        SplitLayout.prototype.onUpdateRequest = function (msg) {
            if (this.parent.isVisible) {
                this._update(-1, -1);
            }
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         */
        SplitLayout.prototype.onFitRequest = function (msg) {
            if (this.parent.isAttached) {
                this._fit();
            }
        };
        /**
         * Update the item position.
         *
         * @param i Item index
         * @param isHorizontal Whether the layout is horizontal or not
         * @param left Left position in pixels
         * @param top Top position in pixels
         * @param height Item height
         * @param width Item width
         * @param size Item size
         */
        SplitLayout.prototype.updateItemPosition = function (i, isHorizontal, left, top, height, width, size) {
            var item = this._items[i];
            if (item.isHidden) {
                return;
            }
            // Fetch the style for the handle.
            var handleStyle = this._handles[i].style;
            // Update the widget and handle, and advance the relevant edge.
            if (isHorizontal) {
                left += this.widgetOffset;
                item.update(left, top, size, height);
                left += size;
                handleStyle.top = top + "px";
                handleStyle.left = left + "px";
                handleStyle.width = this._spacing + "px";
                handleStyle.height = height + "px";
            }
            else {
                top += this.widgetOffset;
                item.update(left, top, width, size);
                top += size;
                handleStyle.top = top + "px";
                handleStyle.left = left + "px";
                handleStyle.width = width + "px";
                handleStyle.height = this._spacing + "px";
            }
        };
        /**
         * Fit the layout to the total size required by the widgets.
         */
        SplitLayout.prototype._fit = function () {
            // Update the handles and track the visible widget count.
            var nVisible = 0;
            var lastHandleIndex = -1;
            for (var i = 0, n = this._items.length; i < n; ++i) {
                if (this._items[i].isHidden) {
                    this._handles[i].classList.add('lm-mod-hidden');
                    /* <DEPRECATED> */
                    this._handles[i].classList.add('p-mod-hidden');
                    /* </DEPRECATED> */
                }
                else {
                    this._handles[i].classList.remove('lm-mod-hidden');
                    /* <DEPRECATED> */
                    this._handles[i].classList.remove('p-mod-hidden');
                    /* </DEPRECATED> */
                    lastHandleIndex = i;
                    nVisible++;
                }
            }
            // Hide the handle for the last visible widget.
            if (lastHandleIndex !== -1) {
                this._handles[lastHandleIndex].classList.add('lm-mod-hidden');
                /* <DEPRECATED> */
                this._handles[lastHandleIndex].classList.add('p-mod-hidden');
                /* </DEPRECATED> */
            }
            // Update the fixed space for the visible items.
            this._fixed =
                this._spacing * Math.max(0, nVisible - 1) +
                    this.widgetOffset * this._items.length;
            // Setup the computed minimum size.
            var horz = this._orientation === 'horizontal';
            var minW = horz ? this._fixed : 0;
            var minH = horz ? 0 : this._fixed;
            // Update the sizers and computed size limits.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item and corresponding box sizer.
                var item = this._items[i];
                var sizer = this._sizers[i];
                // Prevent resizing unless necessary.
                if (sizer.size > 0) {
                    sizer.sizeHint = sizer.size;
                }
                // If the item is hidden, it should consume zero size.
                if (item.isHidden) {
                    sizer.minSize = 0;
                    sizer.maxSize = 0;
                    continue;
                }
                // Update the size limits for the item.
                item.fit();
                // Update the stretch factor.
                sizer.stretch = SplitLayout.getStretch(item.widget);
                // Update the sizer limits and computed min size.
                if (horz) {
                    sizer.minSize = item.minWidth;
                    sizer.maxSize = item.maxWidth;
                    minW += item.minWidth;
                    minH = Math.max(minH, item.minHeight);
                }
                else {
                    sizer.minSize = item.minHeight;
                    sizer.maxSize = item.maxHeight;
                    minH += item.minHeight;
                    minW = Math.max(minW, item.minWidth);
                }
            }
            // Update the box sizing and add it to the computed min size.
            var box = (this._box = domutils.ElementExt.boxSizing(this.parent.node));
            minW += box.horizontalSum;
            minH += box.verticalSum;
            // Update the parent's min size constraints.
            var style = this.parent.node.style;
            style.minWidth = minW + "px";
            style.minHeight = minH + "px";
            // Set the dirty flag to ensure only a single update occurs.
            this._dirty = true;
            // Notify the ancestor that it should fit immediately. This may
            // cause a resize of the parent, fulfilling the required update.
            if (this.parent.parent) {
                messaging.MessageLoop.sendMessage(this.parent.parent, exports.Widget.Msg.FitRequest);
            }
            // If the dirty flag is still set, the parent was not resized.
            // Trigger the required update on the parent widget immediately.
            if (this._dirty) {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
            }
        };
        /**
         * Update the layout position and size of the widgets.
         *
         * The parent offset dimensions should be `-1` if unknown.
         */
        SplitLayout.prototype._update = function (offsetWidth, offsetHeight) {
            // Clear the dirty flag to indicate the update occurred.
            this._dirty = false;
            // Compute the visible item count.
            var nVisible = 0;
            for (var i = 0, n = this._items.length; i < n; ++i) {
                nVisible += +!this._items[i].isHidden;
            }
            // Bail early if there are no visible items to layout.
            if (nVisible === 0 && this.widgetOffset === 0) {
                return;
            }
            // Measure the parent if the offset dimensions are unknown.
            if (offsetWidth < 0) {
                offsetWidth = this.parent.node.offsetWidth;
            }
            if (offsetHeight < 0) {
                offsetHeight = this.parent.node.offsetHeight;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Compute the actual layout bounds adjusted for border and padding.
            var top = this._box.paddingTop;
            var left = this._box.paddingLeft;
            var width = offsetWidth - this._box.horizontalSum;
            var height = offsetHeight - this._box.verticalSum;
            // Set up the variables for justification and alignment offset.
            var extra = 0;
            var offset = 0;
            var horz = this._orientation === 'horizontal';
            if (nVisible > 0) {
                // Compute the adjusted layout space.
                var space = void 0;
                if (horz) {
                    // left += this.widgetOffset;
                    space = Math.max(0, width - this._fixed);
                }
                else {
                    // top += this.widgetOffset;
                    space = Math.max(0, height - this._fixed);
                }
                // Scale the size hints if they are normalized.
                if (this._hasNormedSizes) {
                    for (var _i = 0, _a = this._sizers; _i < _a.length; _i++) {
                        var sizer = _a[_i];
                        sizer.sizeHint *= space;
                    }
                    this._hasNormedSizes = false;
                }
                // Distribute the layout space to the box sizers.
                var delta = exports.BoxEngine.calc(this._sizers, space);
                // Account for alignment if there is extra layout space.
                if (delta > 0) {
                    switch (this._alignment) {
                        case 'start':
                            break;
                        case 'center':
                            extra = 0;
                            offset = delta / 2;
                            break;
                        case 'end':
                            extra = 0;
                            offset = delta;
                            break;
                        case 'justify':
                            extra = delta / nVisible;
                            offset = 0;
                            break;
                        default:
                            throw 'unreachable';
                    }
                }
            }
            // Layout the items using the computed box sizes.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item.
                var item = this._items[i];
                // Fetch the computed size for the widget.
                var size = item.isHidden ? 0 : this._sizers[i].size + extra;
                this.updateItemPosition(i, horz, horz ? left + offset : left, horz ? top : top + offset, height, width, size);
                var fullOffset = this.widgetOffset +
                    (this._handles[i].classList.contains('lm-mod-hidden')
                        ? 0
                        : this._spacing);
                if (horz) {
                    left += size + fullOffset;
                }
                else {
                    top += size + fullOffset;
                }
            }
        };
        return SplitLayout;
    }(PanelLayout));
    /**
     * The namespace for the `SplitLayout` class statics.
     */
    (function (SplitLayout) {
        /**
         * Get the split layout stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The split layout stretch factor for the widget.
         */
        function getStretch(widget) {
            return Private$h.stretchProperty.get(widget);
        }
        SplitLayout.getStretch = getStretch;
        /**
         * Set the split layout stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the stretch factor.
         */
        function setStretch(widget, value) {
            Private$h.stretchProperty.set(widget, value);
        }
        SplitLayout.setStretch = setStretch;
    })(exports.SplitLayout || (exports.SplitLayout = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$h;
    (function (Private) {
        /**
         * The property descriptor for a widget stretch factor.
         */
        Private.stretchProperty = new properties.AttachedProperty({
            name: 'stretch',
            create: function () { return 0; },
            coerce: function (owner, value) { return Math.max(0, Math.floor(value)); },
            changed: onChildSizingChanged
        });
        /**
         * Create a new box sizer with the given size hint.
         */
        function createSizer(size) {
            var sizer = new BoxSizer();
            sizer.sizeHint = Math.floor(size);
            return sizer;
        }
        Private.createSizer = createSizer;
        /**
         * Create a new split handle node using the given renderer.
         */
        function createHandle(renderer) {
            var handle = renderer.createHandle();
            handle.style.position = 'absolute';
            return handle;
        }
        Private.createHandle = createHandle;
        /**
         * Compute the average size of an array of box sizers.
         */
        function averageSize(sizers) {
            return sizers.reduce(function (v, s) { return v + s.size; }, 0) / sizers.length || 0;
        }
        Private.averageSize = averageSize;
        /**
         * Normalize an array of values.
         */
        function normalize(values) {
            var n = values.length;
            if (n === 0) {
                return [];
            }
            var sum = values.reduce(function (a, b) { return a + Math.abs(b); }, 0);
            return sum === 0 ? values.map(function (v) { return 1 / n; }) : values.map(function (v) { return v / sum; });
        }
        Private.normalize = normalize;
        /**
         * The change handler for the attached sizing properties.
         */
        function onChildSizingChanged(child) {
            if (child.parent && child.parent.layout instanceof exports.SplitLayout) {
                child.parent.fit();
            }
        }
    })(Private$h || (Private$h = {}));

    /**
     * A layout which arranges its widgets into collapsible resizable sections.
     */
    var AccordionLayout = /** @class */ (function (_super) {
        __extends(AccordionLayout, _super);
        /**
         * Construct a new accordion layout.
         *
         * @param options - The options for initializing the layout.
         *
         * #### Notes
         * The default orientation will be vertical.
         *
         * Titles must be rotated for horizontal accordion panel using CSS: see accordionpanel.css
         */
        function AccordionLayout(options) {
            var _this = _super.call(this, __assign(__assign({}, options), { orientation: options.orientation || 'vertical' })) || this;
            _this._titles = [];
            _this.titleSpace = options.titleSpace || 22;
            return _this;
        }
        Object.defineProperty(AccordionLayout.prototype, "titleSpace", {
            /**
             * The section title height or width depending on the orientation.
             */
            get: function () {
                return this.widgetOffset;
            },
            set: function (value) {
                value = Utils$1.clampDimension(value);
                if (this.widgetOffset === value) {
                    return;
                }
                this.widgetOffset = value;
                if (!this.parent) {
                    return;
                }
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(AccordionLayout.prototype, "titles", {
            /**
             * A read-only array of the section titles in the panel.
             */
            get: function () {
                return this._titles;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Dispose of the resources held by the layout.
         */
        AccordionLayout.prototype.dispose = function () {
            if (this.isDisposed) {
                return;
            }
            // Clear the layout state.
            this._titles.length = 0;
            // Dispose of the rest of the layout.
            _super.prototype.dispose.call(this);
        };
        AccordionLayout.prototype.updateTitle = function (index, widget) {
            var oldTitle = this._titles[index];
            var expanded = oldTitle.classList.contains('lm-mod-expanded');
            var newTitle = Private$g.createTitle(this.renderer, widget.title, expanded);
            this._titles[index] = newTitle;
            // Add the title node to the parent before the widget.
            this.parent.node.replaceChild(newTitle, oldTitle);
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         */
        AccordionLayout.prototype.attachWidget = function (index, widget) {
            var title = Private$g.createTitle(this.renderer, widget.title);
            algorithm.ArrayExt.insert(this._titles, index, title);
            // Add the title node to the parent before the widget.
            this.parent.node.appendChild(title);
            widget.node.setAttribute('role', 'region');
            widget.node.setAttribute('aria-labelledby', title.id);
            _super.prototype.attachWidget.call(this, index, widget);
        };
        /**
         * Move a widget in the parent's DOM node.
         *
         * @param fromIndex - The previous index of the widget in the layout.
         *
         * @param toIndex - The current index of the widget in the layout.
         *
         * @param widget - The widget to move in the parent.
         */
        AccordionLayout.prototype.moveWidget = function (fromIndex, toIndex, widget) {
            algorithm.ArrayExt.move(this._titles, fromIndex, toIndex);
            _super.prototype.moveWidget.call(this, fromIndex, toIndex, widget);
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param index - The previous index of the widget in the layout.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        AccordionLayout.prototype.detachWidget = function (index, widget) {
            var title = algorithm.ArrayExt.removeAt(this._titles, index);
            this.parent.node.removeChild(title);
            _super.prototype.detachWidget.call(this, index, widget);
        };
        /**
         * Update the item position.
         *
         * @param i Item index
         * @param isHorizontal Whether the layout is horizontal or not
         * @param left Left position in pixels
         * @param top Top position in pixels
         * @param height Item height
         * @param width Item width
         * @param size Item size
         */
        AccordionLayout.prototype.updateItemPosition = function (i, isHorizontal, left, top, height, width, size) {
            var titleStyle = this._titles[i].style;
            // Titles must be rotated for horizontal accordion panel using CSS: see accordionpanel.css
            titleStyle.top = top + "px";
            titleStyle.left = left + "px";
            titleStyle.height = this.widgetOffset + "px";
            if (isHorizontal) {
                titleStyle.width = height + "px";
            }
            else {
                titleStyle.width = width + "px";
            }
            _super.prototype.updateItemPosition.call(this, i, isHorizontal, left, top, height, width, size);
        };
        return AccordionLayout;
    }(exports.SplitLayout));
    var Private$g;
    (function (Private) {
        /**
         * Create the title HTML element.
         *
         * @param renderer Accordion renderer
         * @param data Widget title
         * @returns Title HTML element
         */
        function createTitle(renderer, data, expanded) {
            if (expanded === void 0) { expanded = true; }
            var title = renderer.createSectionTitle(data);
            title.style.position = 'absolute';
            title.setAttribute('aria-label', data.label + " Section");
            title.setAttribute('aria-expanded', expanded ? 'true' : 'false');
            title.setAttribute('aria-controls', data.owner.id);
            if (expanded) {
                title.classList.add('lm-mod-expanded');
            }
            return title;
        }
        Private.createTitle = createTitle;
    })(Private$g || (Private$g = {}));

    /**
     * A simple and convenient panel widget class.
     *
     * #### Notes
     * This class is suitable as a base class for implementing a variety of
     * convenience panel widgets, but can also be used directly with CSS to
     * arrange a collection of widgets.
     *
     * This class provides a convenience wrapper around a [[PanelLayout]].
     */
    var Panel = /** @class */ (function (_super) {
        __extends(Panel, _super);
        /**
         * Construct a new panel.
         *
         * @param options - The options for initializing the panel.
         */
        function Panel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this) || this;
            _this.addClass('lm-Panel');
            /* <DEPRECATED> */
            _this.addClass('p-Panel');
            /* </DEPRECATED> */
            _this.layout = Private$f.createLayout(options);
            return _this;
        }
        Object.defineProperty(Panel.prototype, "widgets", {
            /**
             * A read-only array of the widgets in the panel.
             */
            get: function () {
                return this.layout.widgets;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Add a widget to the end of the panel.
         *
         * @param widget - The widget to add to the panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         */
        Panel.prototype.addWidget = function (widget) {
            this.layout.addWidget(widget);
        };
        /**
         * Insert a widget at the specified index.
         *
         * @param index - The index at which to insert the widget.
         *
         * @param widget - The widget to insert into to the panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         */
        Panel.prototype.insertWidget = function (index, widget) {
            this.layout.insertWidget(index, widget);
        };
        return Panel;
    }(exports.Widget));
    /**
     * The namespace for the module implementation details.
     */
    var Private$f;
    (function (Private) {
        /**
         * Create a panel layout for the given panel options.
         */
        function createLayout(options) {
            return options.layout || new PanelLayout();
        }
        Private.createLayout = createLayout;
    })(Private$f || (Private$f = {}));

    /**
     * A panel which arranges its widgets into resizable sections.
     *
     * #### Notes
     * This class provides a convenience wrapper around a [[SplitLayout]].
     */
    exports.SplitPanel = /** @class */ (function (_super) {
        __extends(SplitPanel, _super);
        /**
         * Construct a new split panel.
         *
         * @param options - The options for initializing the split panel.
         */
        function SplitPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { layout: Private$e.createLayout(options) }) || this;
            _this._handleMoved = new signaling.Signal(_this);
            _this._pressData = null;
            _this.addClass('lm-SplitPanel');
            /* <DEPRECATED> */
            _this.addClass('p-SplitPanel');
            return _this;
            /* </DEPRECATED> */
        }
        /**
         * Dispose of the resources held by the panel.
         */
        SplitPanel.prototype.dispose = function () {
            this._releaseMouse();
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(SplitPanel.prototype, "orientation", {
            /**
             * Get the layout orientation for the split panel.
             */
            get: function () {
                return this.layout.orientation;
            },
            /**
             * Set the layout orientation for the split panel.
             */
            set: function (value) {
                this.layout.orientation = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitPanel.prototype, "alignment", {
            /**
             * Get the content alignment for the split panel.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire split panel.
             */
            get: function () {
                return this.layout.alignment;
            },
            /**
             * Set the content alignment for the split panel.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire split panel.
             */
            set: function (value) {
                this.layout.alignment = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitPanel.prototype, "spacing", {
            /**
             * Get the inter-element spacing for the split panel.
             */
            get: function () {
                return this.layout.spacing;
            },
            /**
             * Set the inter-element spacing for the split panel.
             */
            set: function (value) {
                this.layout.spacing = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitPanel.prototype, "renderer", {
            /**
             * The renderer used by the split panel.
             */
            get: function () {
                return this.layout.renderer;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitPanel.prototype, "handleMoved", {
            /**
             * A signal emitted when a split handle has moved.
             */
            get: function () {
                return this._handleMoved;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(SplitPanel.prototype, "handles", {
            /**
             * A read-only array of the split handles in the panel.
             */
            get: function () {
                return this.layout.handles;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Get the relative sizes of the widgets in the panel.
         *
         * @returns A new array of the relative sizes of the widgets.
         *
         * #### Notes
         * The returned sizes reflect the sizes of the widgets normalized
         * relative to their siblings.
         *
         * This method **does not** measure the DOM nodes.
         */
        SplitPanel.prototype.relativeSizes = function () {
            return this.layout.relativeSizes();
        };
        /**
         * Set the relative sizes for the widgets in the panel.
         *
         * @param sizes - The relative sizes for the widgets in the panel.
         * @param update - Update the layout after setting relative sizes.
         * Default is True.
         *
         * #### Notes
         * Extra values are ignored, too few will yield an undefined layout.
         *
         * The actual geometry of the DOM nodes is updated asynchronously.
         */
        SplitPanel.prototype.setRelativeSizes = function (sizes, update) {
            if (update === void 0) { update = true; }
            this.layout.setRelativeSizes(sizes, update);
        };
        /**
         * Handle the DOM events for the split panel.
         *
         * @param event - The DOM event sent to the panel.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the panel's DOM node. It should
         * not be called directly by user code.
         */
        SplitPanel.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'mousedown':
                    this._evtMouseDown(event);
                    break;
                case 'mousemove':
                    this._evtMouseMove(event);
                    break;
                case 'mouseup':
                    this._evtMouseUp(event);
                    break;
                case 'pointerdown':
                    this._evtMouseDown(event);
                    break;
                case 'pointermove':
                    this._evtMouseMove(event);
                    break;
                case 'pointerup':
                    this._evtMouseUp(event);
                    break;
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        SplitPanel.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('mousedown', this);
            this.node.addEventListener('pointerdown', this);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        SplitPanel.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('mousedown', this);
            this.node.removeEventListener('pointerdown', this);
            this._releaseMouse();
        };
        /**
         * A message handler invoked on a `'child-added'` message.
         */
        SplitPanel.prototype.onChildAdded = function (msg) {
            msg.child.addClass('lm-SplitPanel-child');
            /* <DEPRECATED> */
            msg.child.addClass('p-SplitPanel-child');
            /* </DEPRECATED> */
            this._releaseMouse();
        };
        /**
         * A message handler invoked on a `'child-removed'` message.
         */
        SplitPanel.prototype.onChildRemoved = function (msg) {
            msg.child.removeClass('lm-SplitPanel-child');
            /* <DEPRECATED> */
            msg.child.removeClass('p-SplitPanel-child');
            /* </DEPRECATED> */
            this._releaseMouse();
        };
        /**
         * Handle the `'keydown'` event for the split panel.
         */
        SplitPanel.prototype._evtKeyDown = function (event) {
            // Stop input events during drag.
            if (this._pressData) {
                event.preventDefault();
                event.stopPropagation();
            }
            // Release the mouse if `Escape` is pressed.
            if (event.keyCode === 27) {
                this._releaseMouse();
            }
        };
        /**
         * Handle the `'mousedown'` event for the split panel.
         */
        SplitPanel.prototype._evtMouseDown = function (event) {
            // Do nothing if the left mouse button is not pressed.
            if (event.button !== 0) {
                return;
            }
            // Find the handle which contains the mouse target, if any.
            var layout = this.layout;
            var index = algorithm.ArrayExt.findFirstIndex(layout.handles, function (handle) {
                return handle.contains(event.target);
            });
            // Bail early if the mouse press was not on a handle.
            if (index === -1) {
                return;
            }
            // Stop the event when a split handle is pressed.
            event.preventDefault();
            event.stopPropagation();
            // Add the extra document listeners.
            document.addEventListener('mouseup', this, true);
            document.addEventListener('mousemove', this, true);
            document.addEventListener('pointerup', this, true);
            document.addEventListener('pointermove', this, true);
            document.addEventListener('keydown', this, true);
            document.addEventListener('contextmenu', this, true);
            // Compute the offset delta for the handle press.
            var delta;
            var handle = layout.handles[index];
            var rect = handle.getBoundingClientRect();
            if (layout.orientation === 'horizontal') {
                delta = event.clientX - rect.left;
            }
            else {
                delta = event.clientY - rect.top;
            }
            // Override the cursor and store the press data.
            var style = window.getComputedStyle(handle);
            var override = dragdrop.Drag.overrideCursor(style.cursor);
            this._pressData = { index: index, delta: delta, override: override };
        };
        /**
         * Handle the `'mousemove'` event for the split panel.
         */
        SplitPanel.prototype._evtMouseMove = function (event) {
            // Stop the event when dragging a split handle.
            event.preventDefault();
            event.stopPropagation();
            // Compute the desired offset position for the handle.
            var pos;
            var layout = this.layout;
            var rect = this.node.getBoundingClientRect();
            if (layout.orientation === 'horizontal') {
                pos = event.clientX - rect.left - this._pressData.delta;
            }
            else {
                pos = event.clientY - rect.top - this._pressData.delta;
            }
            // Move the handle as close to the desired position as possible.
            layout.moveHandle(this._pressData.index, pos);
        };
        /**
         * Handle the `'mouseup'` event for the split panel.
         */
        SplitPanel.prototype._evtMouseUp = function (event) {
            // Do nothing if the left mouse button is not released.
            if (event.button !== 0) {
                return;
            }
            // Stop the event when releasing a handle.
            event.preventDefault();
            event.stopPropagation();
            // Finalize the mouse release.
            this._releaseMouse();
        };
        /**
         * Release the mouse grab for the split panel.
         */
        SplitPanel.prototype._releaseMouse = function () {
            // Bail early if no drag is in progress.
            if (!this._pressData) {
                return;
            }
            // Clear the override cursor.
            this._pressData.override.dispose();
            this._pressData = null;
            // Emit the handle moved signal.
            this._handleMoved.emit();
            // Remove the extra document listeners.
            document.removeEventListener('mouseup', this, true);
            document.removeEventListener('mousemove', this, true);
            document.removeEventListener('keydown', this, true);
            document.removeEventListener('pointerup', this, true);
            document.removeEventListener('pointermove', this, true);
            document.removeEventListener('contextmenu', this, true);
        };
        return SplitPanel;
    }(Panel));
    /**
     * The namespace for the `SplitPanel` class statics.
     */
    (function (SplitPanel) {
        /**
         * The default implementation of `IRenderer`.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
            }
            /**
             * Create a new handle for use with a split panel.
             *
             * @returns A new handle element for a split panel.
             */
            Renderer.prototype.createHandle = function () {
                var handle = document.createElement('div');
                handle.className = 'lm-SplitPanel-handle';
                /* <DEPRECATED> */
                handle.classList.add('p-SplitPanel-handle');
                /* </DEPRECATED> */
                return handle;
            };
            return Renderer;
        }());
        SplitPanel.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        SplitPanel.defaultRenderer = new Renderer();
        /**
         * Get the split panel stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The split panel stretch factor for the widget.
         */
        function getStretch(widget) {
            return exports.SplitLayout.getStretch(widget);
        }
        SplitPanel.getStretch = getStretch;
        /**
         * Set the split panel stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the stretch factor.
         */
        function setStretch(widget, value) {
            exports.SplitLayout.setStretch(widget, value);
        }
        SplitPanel.setStretch = setStretch;
    })(exports.SplitPanel || (exports.SplitPanel = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$e;
    (function (Private) {
        /**
         * Create a split layout for the given panel options.
         */
        function createLayout(options) {
            return (options.layout ||
                new exports.SplitLayout({
                    renderer: options.renderer || exports.SplitPanel.defaultRenderer,
                    orientation: options.orientation,
                    alignment: options.alignment,
                    spacing: options.spacing
                }));
        }
        Private.createLayout = createLayout;
    })(Private$e || (Private$e = {}));

    // Copyright (c) Jupyter Development Team.
    /**
     * A panel which arranges its widgets into resizable sections separated by a title widget.
     *
     * #### Notes
     * This class provides a convenience wrapper around [[AccordionLayout]].
     */
    exports.AccordionPanel = /** @class */ (function (_super) {
        __extends(AccordionPanel, _super);
        /**
         * Construct a new accordion panel.
         *
         * @param options - The options for initializing the accordion panel.
         */
        function AccordionPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, __assign(__assign({}, options), { layout: Private$d.createLayout(options) })) || this;
            _this._widgetSizesCache = new WeakMap();
            _this.addClass('lm-AccordionPanel');
            return _this;
        }
        Object.defineProperty(AccordionPanel.prototype, "renderer", {
            /**
             * The renderer used by the accordion panel.
             */
            get: function () {
                return this.layout.renderer;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(AccordionPanel.prototype, "titleSpace", {
            /**
             * The section title space.
             *
             * This is the height if the panel is vertical and the width if it is
             * horizontal.
             */
            get: function () {
                return this.layout.titleSpace;
            },
            set: function (value) {
                this.layout.titleSpace = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(AccordionPanel.prototype, "titles", {
            /**
             * A read-only array of the section titles in the panel.
             */
            get: function () {
                return this.layout.titles;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Add a widget to the end of the panel.
         *
         * @param widget - The widget to add to the panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         */
        AccordionPanel.prototype.addWidget = function (widget) {
            _super.prototype.addWidget.call(this, widget);
            widget.title.changed.connect(this._onTitleChanged, this);
        };
        /**
         * Collapse the widget at position `index`.
         *
         * #### Notes
         * If no widget is found for `index`, this will bail.
         *
         * @param index Widget index
         */
        AccordionPanel.prototype.collapse = function (index) {
            var widget = this.layout.widgets[index];
            if (widget && !widget.isHidden) {
                this._toggleExpansion(index);
            }
        };
        /**
         * Expand the widget at position `index`.
         *
         * #### Notes
         * If no widget is found for `index`, this will bail.
         *
         * @param index Widget index
         */
        AccordionPanel.prototype.expand = function (index) {
            var widget = this.layout.widgets[index];
            if (widget && widget.isHidden) {
                this._toggleExpansion(index);
            }
        };
        /**
         * Insert a widget at the specified index.
         *
         * @param index - The index at which to insert the widget.
         *
         * @param widget - The widget to insert into to the panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         */
        AccordionPanel.prototype.insertWidget = function (index, widget) {
            _super.prototype.insertWidget.call(this, index, widget);
            widget.title.changed.connect(this._onTitleChanged, this);
        };
        /**
         * Handle the DOM events for the accordion panel.
         *
         * @param event - The DOM event sent to the panel.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the panel's DOM node. It should
         * not be called directly by user code.
         */
        AccordionPanel.prototype.handleEvent = function (event) {
            _super.prototype.handleEvent.call(this, event);
            switch (event.type) {
                case 'click':
                    this._evtClick(event);
                    break;
                case 'keydown':
                    this._eventKeyDown(event);
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        AccordionPanel.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('click', this);
            this.node.addEventListener('keydown', this);
            _super.prototype.onBeforeAttach.call(this, msg);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        AccordionPanel.prototype.onAfterDetach = function (msg) {
            _super.prototype.onAfterDetach.call(this, msg);
            this.node.removeEventListener('click', this);
            this.node.removeEventListener('keydown', this);
        };
        /**
         * Handle the `changed` signal of a title object.
         */
        AccordionPanel.prototype._onTitleChanged = function (sender) {
            var index = algorithm.ArrayExt.findFirstIndex(this.widgets, function (widget) {
                return widget.contains(sender.owner);
            });
            if (index >= 0) {
                this.layout.updateTitle(index, sender.owner);
                this.update();
            }
        };
        /**
         * Compute the size of widgets in this panel on the title click event.
         * On closing, the size of the widget is cached and we will try to expand
         * the last opened widget.
         * On opening, we will use the cached size if it is available to restore the
         * widget.
         * In both cases, if we can not compute the size of widgets, we will let
         * `SplitLayout` decide.
         *
         * @param index - The index of widget to be opened of closed
         *
         * @returns Relative size of widgets in this panel, if this size can
         * not be computed, return `undefined`
         */
        AccordionPanel.prototype._computeWidgetSize = function (index) {
            var layout = this.layout;
            var widget = layout.widgets[index];
            if (!widget) {
                return undefined;
            }
            var isHidden = widget.isHidden;
            var widgetSizes = layout.absoluteSizes();
            var delta = (isHidden ? -1 : 1) * this.spacing;
            var totalSize = widgetSizes.reduce(function (prev, curr) { return prev + curr; });
            var newSize = __spreadArrays(widgetSizes);
            if (!isHidden) {
                // Hide the widget
                var currentSize = widgetSizes[index];
                this._widgetSizesCache.set(widget, currentSize);
                newSize[index] = 0;
                var widgetToCollapse = newSize.map(function (sz) { return sz > 0; }).lastIndexOf(true);
                if (widgetToCollapse === -1) {
                    // All widget are closed, let the `SplitLayout` compute widget sizes.
                    return undefined;
                }
                newSize[widgetToCollapse] =
                    widgetSizes[widgetToCollapse] + currentSize + delta;
            }
            else {
                // Show the widget
                var previousSize_1 = this._widgetSizesCache.get(widget);
                if (!previousSize_1) {
                    // Previous size is unavailable, let the `SplitLayout` compute widget sizes.
                    return undefined;
                }
                newSize[index] += previousSize_1;
                var widgetToCollapse = newSize
                    .map(function (sz) { return sz - previousSize_1 > 0; })
                    .lastIndexOf(true);
                if (widgetToCollapse === -1) {
                    // Can not reduce the size of one widget, reduce all opened widgets
                    // proportionally with its size.
                    newSize.forEach(function (_, idx) {
                        if (idx !== index) {
                            newSize[idx] -=
                                (widgetSizes[idx] / totalSize) * (previousSize_1 - delta);
                        }
                    });
                }
                else {
                    newSize[widgetToCollapse] -= previousSize_1 - delta;
                }
            }
            return newSize.map(function (sz) { return sz / (totalSize + delta); });
        };
        /**
         * Handle the `'click'` event for the accordion panel
         */
        AccordionPanel.prototype._evtClick = function (event) {
            var target = event.target;
            if (target) {
                var index = algorithm.ArrayExt.findFirstIndex(this.titles, function (title) {
                    return title.contains(target);
                });
                if (index >= 0) {
                    event.preventDefault();
                    event.stopPropagation();
                    this._toggleExpansion(index);
                }
            }
        };
        /**
         * Handle the `'keydown'` event for the accordion panel.
         */
        AccordionPanel.prototype._eventKeyDown = function (event) {
            if (event.defaultPrevented) {
                return;
            }
            var target = event.target;
            var handled = false;
            if (target) {
                var index = algorithm.ArrayExt.findFirstIndex(this.titles, function (title) {
                    return title.contains(target);
                });
                if (index >= 0) {
                    var keyCode = event.keyCode.toString();
                    // If Space or Enter is pressed on title, emulate click event
                    if (event.key.match(/Space|Enter/) || keyCode.match(/13|32/)) {
                        target.click();
                        handled = true;
                    }
                    else if (this.orientation === 'horizontal'
                        ? event.key.match(/ArrowLeft|ArrowRight/) || keyCode.match(/37|39/)
                        : event.key.match(/ArrowUp|ArrowDown/) || keyCode.match(/38|40/)) {
                        // If Up or Down (for vertical) / Left or Right (for horizontal) is pressed on title, loop on titles
                        var direction = event.key.match(/ArrowLeft|ArrowUp/) || keyCode.match(/37|38/)
                            ? -1
                            : 1;
                        var length_1 = this.titles.length;
                        var newIndex = (index + length_1 + direction) % length_1;
                        this.titles[newIndex].focus();
                        handled = true;
                    }
                    else if (event.key === 'End' || keyCode === '35') {
                        // If End is pressed on title, focus on the last title
                        this.titles[this.titles.length - 1].focus();
                        handled = true;
                    }
                    else if (event.key === 'Home' || keyCode === '36') {
                        // If Home is pressed on title, focus on the first title
                        this.titles[0].focus();
                        handled = true;
                    }
                }
                if (handled) {
                    event.preventDefault();
                }
            }
        };
        AccordionPanel.prototype._toggleExpansion = function (index) {
            var title = this.titles[index];
            var widget = this.layout.widgets[index];
            var newSize = this._computeWidgetSize(index);
            if (newSize) {
                this.setRelativeSizes(newSize, false);
            }
            if (widget.isHidden) {
                title.classList.add('lm-mod-expanded');
                title.setAttribute('aria-expanded', 'true');
                widget.show();
            }
            else {
                title.classList.remove('lm-mod-expanded');
                title.setAttribute('aria-expanded', 'false');
                widget.hide();
            }
        };
        return AccordionPanel;
    }(exports.SplitPanel));
    /**
     * The namespace for the `AccordionPanel` class statics.
     */
    (function (AccordionPanel) {
        /**
         * The default implementation of `IRenderer`.
         */
        var Renderer = /** @class */ (function (_super) {
            __extends(Renderer, _super);
            function Renderer() {
                var _this = _super !== null && _super.apply(this, arguments) || this;
                /**
                 * A selector which matches any title node in the accordion.
                 */
                _this.titleClassName = 'lm-AccordionPanel-title';
                _this._titleID = 0;
                _this._titleKeys = new WeakMap();
                return _this;
            }
            /**
             * Render the collapse indicator for a section title.
             *
             * @param data - The data to use for rendering the section title.
             *
             * @returns A element representing the collapse indicator.
             */
            Renderer.prototype.createCollapseIcon = function (data) {
                return document.createElement('span');
            };
            /**
             * Render the element for a section title.
             *
             * @param data - The data to use for rendering the section title.
             *
             * @returns A element representing the section title.
             */
            Renderer.prototype.createSectionTitle = function (data) {
                var handle = document.createElement('h3');
                handle.setAttribute('role', 'button');
                handle.setAttribute('tabindex', '0');
                handle.id = this.createTitleKey(data);
                handle.className = this.titleClassName;
                handle.title = data.caption;
                for (var aData in data.dataset) {
                    handle.dataset[aData] = data.dataset[aData];
                }
                var collapser = handle.appendChild(this.createCollapseIcon(data));
                collapser.className = 'lm-AccordionPanel-titleCollapser';
                var label = handle.appendChild(document.createElement('span'));
                label.className = 'lm-AccordionPanel-titleLabel';
                label.textContent = data.label;
                return handle;
            };
            /**
             * Create a unique render key for the title.
             *
             * @param data - The data to use for the title.
             *
             * @returns The unique render key for the title.
             *
             * #### Notes
             * This method caches the key against the section title the first time
             * the key is generated.
             */
            Renderer.prototype.createTitleKey = function (data) {
                var key = this._titleKeys.get(data);
                if (key === undefined) {
                    key = "title-key-" + this._titleID++;
                    this._titleKeys.set(data, key);
                }
                return key;
            };
            return Renderer;
        }(exports.SplitPanel.Renderer));
        AccordionPanel.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        AccordionPanel.defaultRenderer = new Renderer();
    })(exports.AccordionPanel || (exports.AccordionPanel = {}));
    var Private$d;
    (function (Private) {
        /**
         * Create an accordion layout for the given panel options.
         *
         * @param options Panel options
         * @returns Panel layout
         */
        function createLayout(options) {
            return (options.layout ||
                new AccordionLayout({
                    renderer: options.renderer || exports.AccordionPanel.defaultRenderer,
                    orientation: options.orientation,
                    alignment: options.alignment,
                    spacing: options.spacing,
                    titleSpace: options.titleSpace
                }));
        }
        Private.createLayout = createLayout;
    })(Private$d || (Private$d = {}));

    /**
     * A layout which arranges its widgets in a single row or column.
     */
    exports.BoxLayout = /** @class */ (function (_super) {
        __extends(BoxLayout, _super);
        /**
         * Construct a new box layout.
         *
         * @param options - The options for initializing the layout.
         */
        function BoxLayout(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this) || this;
            _this._fixed = 0;
            _this._spacing = 4;
            _this._dirty = false;
            _this._sizers = [];
            _this._items = [];
            _this._box = null;
            _this._alignment = 'start';
            _this._direction = 'top-to-bottom';
            if (options.direction !== undefined) {
                _this._direction = options.direction;
            }
            if (options.alignment !== undefined) {
                _this._alignment = options.alignment;
            }
            if (options.spacing !== undefined) {
                _this._spacing = Utils$1.clampDimension(options.spacing);
            }
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         */
        BoxLayout.prototype.dispose = function () {
            // Dispose of the layout items.
            algorithm.each(this._items, function (item) {
                item.dispose();
            });
            // Clear the layout state.
            this._box = null;
            this._items.length = 0;
            this._sizers.length = 0;
            // Dispose of the rest of the layout.
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(BoxLayout.prototype, "direction", {
            /**
             * Get the layout direction for the box layout.
             */
            get: function () {
                return this._direction;
            },
            /**
             * Set the layout direction for the box layout.
             */
            set: function (value) {
                if (this._direction === value) {
                    return;
                }
                this._direction = value;
                if (!this.parent) {
                    return;
                }
                this.parent.dataset['direction'] = value;
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(BoxLayout.prototype, "alignment", {
            /**
             * Get the content alignment for the box layout.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire box layout.
             */
            get: function () {
                return this._alignment;
            },
            /**
             * Set the content alignment for the box layout.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire box layout.
             */
            set: function (value) {
                if (this._alignment === value) {
                    return;
                }
                this._alignment = value;
                if (!this.parent) {
                    return;
                }
                this.parent.dataset['alignment'] = value;
                this.parent.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(BoxLayout.prototype, "spacing", {
            /**
             * Get the inter-element spacing for the box layout.
             */
            get: function () {
                return this._spacing;
            },
            /**
             * Set the inter-element spacing for the box layout.
             */
            set: function (value) {
                value = Utils$1.clampDimension(value);
                if (this._spacing === value) {
                    return;
                }
                this._spacing = value;
                if (!this.parent) {
                    return;
                }
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Perform layout initialization which requires the parent widget.
         */
        BoxLayout.prototype.init = function () {
            this.parent.dataset['direction'] = this.direction;
            this.parent.dataset['alignment'] = this.alignment;
            _super.prototype.init.call(this);
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        BoxLayout.prototype.attachWidget = function (index, widget) {
            // Create and add a new layout item for the widget.
            algorithm.ArrayExt.insert(this._items, index, new LayoutItem(widget));
            // Create and add a new sizer for the widget.
            algorithm.ArrayExt.insert(this._sizers, index, new BoxSizer());
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget's node to the parent.
            this.parent.node.appendChild(widget.node);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Move a widget in the parent's DOM node.
         *
         * @param fromIndex - The previous index of the widget in the layout.
         *
         * @param toIndex - The current index of the widget in the layout.
         *
         * @param widget - The widget to move in the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        BoxLayout.prototype.moveWidget = function (fromIndex, toIndex, widget) {
            // Move the layout item for the widget.
            algorithm.ArrayExt.move(this._items, fromIndex, toIndex);
            // Move the sizer for the widget.
            algorithm.ArrayExt.move(this._sizers, fromIndex, toIndex);
            // Post an update request for the parent widget.
            this.parent.update();
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param index - The previous index of the widget in the layout.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        BoxLayout.prototype.detachWidget = function (index, widget) {
            // Remove the layout item for the widget.
            var item = algorithm.ArrayExt.removeAt(this._items, index);
            // Remove the sizer for the widget.
            algorithm.ArrayExt.removeAt(this._sizers, index);
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Dispose of the layout item.
            item.dispose();
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         */
        BoxLayout.prototype.onBeforeShow = function (msg) {
            _super.prototype.onBeforeShow.call(this, msg);
            this.parent.update();
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        BoxLayout.prototype.onBeforeAttach = function (msg) {
            _super.prototype.onBeforeAttach.call(this, msg);
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-shown'` message.
         */
        BoxLayout.prototype.onChildShown = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         */
        BoxLayout.prototype.onChildHidden = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'resize'` message.
         */
        BoxLayout.prototype.onResize = function (msg) {
            if (this.parent.isVisible) {
                this._update(msg.width, msg.height);
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        BoxLayout.prototype.onUpdateRequest = function (msg) {
            if (this.parent.isVisible) {
                this._update(-1, -1);
            }
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         */
        BoxLayout.prototype.onFitRequest = function (msg) {
            if (this.parent.isAttached) {
                this._fit();
            }
        };
        /**
         * Fit the layout to the total size required by the widgets.
         */
        BoxLayout.prototype._fit = function () {
            // Compute the visible item count.
            var nVisible = 0;
            for (var i = 0, n = this._items.length; i < n; ++i) {
                nVisible += +!this._items[i].isHidden;
            }
            // Update the fixed space for the visible items.
            this._fixed = this._spacing * Math.max(0, nVisible - 1);
            // Setup the computed minimum size.
            var horz = Private$c.isHorizontal(this._direction);
            var minW = horz ? this._fixed : 0;
            var minH = horz ? 0 : this._fixed;
            // Update the sizers and computed minimum size.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item and corresponding box sizer.
                var item = this._items[i];
                var sizer = this._sizers[i];
                // If the item is hidden, it should consume zero size.
                if (item.isHidden) {
                    sizer.minSize = 0;
                    sizer.maxSize = 0;
                    continue;
                }
                // Update the size limits for the item.
                item.fit();
                // Update the size basis and stretch factor.
                sizer.sizeHint = BoxLayout.getSizeBasis(item.widget);
                sizer.stretch = BoxLayout.getStretch(item.widget);
                // Update the sizer limits and computed min size.
                if (horz) {
                    sizer.minSize = item.minWidth;
                    sizer.maxSize = item.maxWidth;
                    minW += item.minWidth;
                    minH = Math.max(minH, item.minHeight);
                }
                else {
                    sizer.minSize = item.minHeight;
                    sizer.maxSize = item.maxHeight;
                    minH += item.minHeight;
                    minW = Math.max(minW, item.minWidth);
                }
            }
            // Update the box sizing and add it to the computed min size.
            var box = (this._box = domutils.ElementExt.boxSizing(this.parent.node));
            minW += box.horizontalSum;
            minH += box.verticalSum;
            // Update the parent's min size constraints.
            var style = this.parent.node.style;
            style.minWidth = minW + "px";
            style.minHeight = minH + "px";
            // Set the dirty flag to ensure only a single update occurs.
            this._dirty = true;
            // Notify the ancestor that it should fit immediately. This may
            // cause a resize of the parent, fulfilling the required update.
            if (this.parent.parent) {
                messaging.MessageLoop.sendMessage(this.parent.parent, exports.Widget.Msg.FitRequest);
            }
            // If the dirty flag is still set, the parent was not resized.
            // Trigger the required update on the parent widget immediately.
            if (this._dirty) {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
            }
        };
        /**
         * Update the layout position and size of the widgets.
         *
         * The parent offset dimensions should be `-1` if unknown.
         */
        BoxLayout.prototype._update = function (offsetWidth, offsetHeight) {
            // Clear the dirty flag to indicate the update occurred.
            this._dirty = false;
            // Compute the visible item count.
            var nVisible = 0;
            for (var i = 0, n = this._items.length; i < n; ++i) {
                nVisible += +!this._items[i].isHidden;
            }
            // Bail early if there are no visible items to layout.
            if (nVisible === 0) {
                return;
            }
            // Measure the parent if the offset dimensions are unknown.
            if (offsetWidth < 0) {
                offsetWidth = this.parent.node.offsetWidth;
            }
            if (offsetHeight < 0) {
                offsetHeight = this.parent.node.offsetHeight;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Compute the layout area adjusted for border and padding.
            var top = this._box.paddingTop;
            var left = this._box.paddingLeft;
            var width = offsetWidth - this._box.horizontalSum;
            var height = offsetHeight - this._box.verticalSum;
            // Distribute the layout space and adjust the start position.
            var delta;
            switch (this._direction) {
                case 'left-to-right':
                    delta = exports.BoxEngine.calc(this._sizers, Math.max(0, width - this._fixed));
                    break;
                case 'top-to-bottom':
                    delta = exports.BoxEngine.calc(this._sizers, Math.max(0, height - this._fixed));
                    break;
                case 'right-to-left':
                    delta = exports.BoxEngine.calc(this._sizers, Math.max(0, width - this._fixed));
                    left += width;
                    break;
                case 'bottom-to-top':
                    delta = exports.BoxEngine.calc(this._sizers, Math.max(0, height - this._fixed));
                    top += height;
                    break;
                default:
                    throw 'unreachable';
            }
            // Setup the variables for justification and alignment offset.
            var extra = 0;
            var offset = 0;
            // Account for alignment if there is extra layout space.
            if (delta > 0) {
                switch (this._alignment) {
                    case 'start':
                        break;
                    case 'center':
                        extra = 0;
                        offset = delta / 2;
                        break;
                    case 'end':
                        extra = 0;
                        offset = delta;
                        break;
                    case 'justify':
                        extra = delta / nVisible;
                        offset = 0;
                        break;
                    default:
                        throw 'unreachable';
                }
            }
            // Layout the items using the computed box sizes.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item.
                var item = this._items[i];
                // Ignore hidden items.
                if (item.isHidden) {
                    continue;
                }
                // Fetch the computed size for the widget.
                var size = this._sizers[i].size;
                // Update the widget geometry and advance the relevant edge.
                switch (this._direction) {
                    case 'left-to-right':
                        item.update(left + offset, top, size + extra, height);
                        left += size + extra + this._spacing;
                        break;
                    case 'top-to-bottom':
                        item.update(left, top + offset, width, size + extra);
                        top += size + extra + this._spacing;
                        break;
                    case 'right-to-left':
                        item.update(left - offset - size - extra, top, size + extra, height);
                        left -= size + extra + this._spacing;
                        break;
                    case 'bottom-to-top':
                        item.update(left, top - offset - size - extra, width, size + extra);
                        top -= size + extra + this._spacing;
                        break;
                    default:
                        throw 'unreachable';
                }
            }
        };
        return BoxLayout;
    }(PanelLayout));
    /**
     * The namespace for the `BoxLayout` class statics.
     */
    (function (BoxLayout) {
        /**
         * Get the box layout stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The box layout stretch factor for the widget.
         */
        function getStretch(widget) {
            return Private$c.stretchProperty.get(widget);
        }
        BoxLayout.getStretch = getStretch;
        /**
         * Set the box layout stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the stretch factor.
         */
        function setStretch(widget, value) {
            Private$c.stretchProperty.set(widget, value);
        }
        BoxLayout.setStretch = setStretch;
        /**
         * Get the box layout size basis for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The box layout size basis for the widget.
         */
        function getSizeBasis(widget) {
            return Private$c.sizeBasisProperty.get(widget);
        }
        BoxLayout.getSizeBasis = getSizeBasis;
        /**
         * Set the box layout size basis for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the size basis.
         */
        function setSizeBasis(widget, value) {
            Private$c.sizeBasisProperty.set(widget, value);
        }
        BoxLayout.setSizeBasis = setSizeBasis;
    })(exports.BoxLayout || (exports.BoxLayout = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$c;
    (function (Private) {
        /**
         * The property descriptor for a widget stretch factor.
         */
        Private.stretchProperty = new properties.AttachedProperty({
            name: 'stretch',
            create: function () { return 0; },
            coerce: function (owner, value) { return Math.max(0, Math.floor(value)); },
            changed: onChildSizingChanged
        });
        /**
         * The property descriptor for a widget size basis.
         */
        Private.sizeBasisProperty = new properties.AttachedProperty({
            name: 'sizeBasis',
            create: function () { return 0; },
            coerce: function (owner, value) { return Math.max(0, Math.floor(value)); },
            changed: onChildSizingChanged
        });
        /**
         * Test whether a direction has horizontal orientation.
         */
        function isHorizontal(dir) {
            return dir === 'left-to-right' || dir === 'right-to-left';
        }
        Private.isHorizontal = isHorizontal;
        /**
         * Clamp a spacing value to an integer >= 0.
         */
        function clampSpacing(value) {
            return Math.max(0, Math.floor(value));
        }
        Private.clampSpacing = clampSpacing;
        /**
         * The change handler for the attached sizing properties.
         */
        function onChildSizingChanged(child) {
            if (child.parent && child.parent.layout instanceof exports.BoxLayout) {
                child.parent.fit();
            }
        }
    })(Private$c || (Private$c = {}));

    /**
     * A panel which arranges its widgets in a single row or column.
     *
     * #### Notes
     * This class provides a convenience wrapper around a [[BoxLayout]].
     */
    exports.BoxPanel = /** @class */ (function (_super) {
        __extends(BoxPanel, _super);
        /**
         * Construct a new box panel.
         *
         * @param options - The options for initializing the box panel.
         */
        function BoxPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { layout: Private$b.createLayout(options) }) || this;
            _this.addClass('lm-BoxPanel');
            /* <DEPRECATED> */
            _this.addClass('p-BoxPanel');
            return _this;
            /* </DEPRECATED> */
        }
        Object.defineProperty(BoxPanel.prototype, "direction", {
            /**
             * Get the layout direction for the box panel.
             */
            get: function () {
                return this.layout.direction;
            },
            /**
             * Set the layout direction for the box panel.
             */
            set: function (value) {
                this.layout.direction = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(BoxPanel.prototype, "alignment", {
            /**
             * Get the content alignment for the box panel.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire box layout.
             */
            get: function () {
                return this.layout.alignment;
            },
            /**
             * Set the content alignment for the box panel.
             *
             * #### Notes
             * This is the alignment of the widgets in the layout direction.
             *
             * The alignment has no effect if the widgets can expand to fill the
             * entire box layout.
             */
            set: function (value) {
                this.layout.alignment = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(BoxPanel.prototype, "spacing", {
            /**
             * Get the inter-element spacing for the box panel.
             */
            get: function () {
                return this.layout.spacing;
            },
            /**
             * Set the inter-element spacing for the box panel.
             */
            set: function (value) {
                this.layout.spacing = value;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * A message handler invoked on a `'child-added'` message.
         */
        BoxPanel.prototype.onChildAdded = function (msg) {
            msg.child.addClass('lm-BoxPanel-child');
            /* <DEPRECATED> */
            msg.child.addClass('p-BoxPanel-child');
            /* </DEPRECATED> */
        };
        /**
         * A message handler invoked on a `'child-removed'` message.
         */
        BoxPanel.prototype.onChildRemoved = function (msg) {
            msg.child.removeClass('lm-BoxPanel-child');
            /* <DEPRECATED> */
            msg.child.removeClass('p-BoxPanel-child');
            /* </DEPRECATED> */
        };
        return BoxPanel;
    }(Panel));
    /**
     * The namespace for the `BoxPanel` class statics.
     */
    (function (BoxPanel) {
        /**
         * Get the box panel stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The box panel stretch factor for the widget.
         */
        function getStretch(widget) {
            return exports.BoxLayout.getStretch(widget);
        }
        BoxPanel.getStretch = getStretch;
        /**
         * Set the box panel stretch factor for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the stretch factor.
         */
        function setStretch(widget, value) {
            exports.BoxLayout.setStretch(widget, value);
        }
        BoxPanel.setStretch = setStretch;
        /**
         * Get the box panel size basis for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The box panel size basis for the widget.
         */
        function getSizeBasis(widget) {
            return exports.BoxLayout.getSizeBasis(widget);
        }
        BoxPanel.getSizeBasis = getSizeBasis;
        /**
         * Set the box panel size basis for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the size basis.
         */
        function setSizeBasis(widget, value) {
            exports.BoxLayout.setSizeBasis(widget, value);
        }
        BoxPanel.setSizeBasis = setSizeBasis;
    })(exports.BoxPanel || (exports.BoxPanel = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$b;
    (function (Private) {
        /**
         * Create a box layout for the given panel options.
         */
        function createLayout(options) {
            return options.layout || new exports.BoxLayout(options);
        }
        Private.createLayout = createLayout;
    })(Private$b || (Private$b = {}));

    /**
     * A widget which displays command items as a searchable palette.
     */
    exports.CommandPalette = /** @class */ (function (_super) {
        __extends(CommandPalette, _super);
        /**
         * Construct a new command palette.
         *
         * @param options - The options for initializing the palette.
         */
        function CommandPalette(options) {
            var _this = _super.call(this, { node: Private$a.createNode() }) || this;
            _this._activeIndex = -1;
            _this._items = [];
            _this._results = null;
            _this.addClass('lm-CommandPalette');
            /* <DEPRECATED> */
            _this.addClass('p-CommandPalette');
            /* </DEPRECATED> */
            _this.setFlag(exports.Widget.Flag.DisallowLayout);
            _this.commands = options.commands;
            _this.renderer = options.renderer || CommandPalette.defaultRenderer;
            _this.commands.commandChanged.connect(_this._onGenericChange, _this);
            _this.commands.keyBindingChanged.connect(_this._onGenericChange, _this);
            return _this;
        }
        /**
         * Dispose of the resources held by the widget.
         */
        CommandPalette.prototype.dispose = function () {
            this._items.length = 0;
            this._results = null;
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(CommandPalette.prototype, "searchNode", {
            /**
             * The command palette search node.
             *
             * #### Notes
             * This is the node which contains the search-related elements.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-CommandPalette-search')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(CommandPalette.prototype, "inputNode", {
            /**
             * The command palette input node.
             *
             * #### Notes
             * This is the actual input node for the search area.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-CommandPalette-input')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(CommandPalette.prototype, "contentNode", {
            /**
             * The command palette content node.
             *
             * #### Notes
             * This is the node which holds the command item nodes.
             *
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-CommandPalette-content')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(CommandPalette.prototype, "items", {
            /**
             * A read-only array of the command items in the palette.
             */
            get: function () {
                return this._items;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Add a command item to the command palette.
         *
         * @param options - The options for creating the command item.
         *
         * @returns The command item added to the palette.
         */
        CommandPalette.prototype.addItem = function (options) {
            // Create a new command item for the options.
            var item = Private$a.createItem(this.commands, options);
            // Add the item to the array.
            this._items.push(item);
            // Refresh the search results.
            this.refresh();
            // Return the item added to the palette.
            return item;
        };
        /**
         * Adds command items to the command palette.
         *
         * @param items - An array of options for creating each command item.
         *
         * @returns The command items added to the palette.
         */
        CommandPalette.prototype.addItems = function (items) {
            var _this = this;
            var newItems = items.map(function (item) { return Private$a.createItem(_this.commands, item); });
            newItems.forEach(function (item) { return _this._items.push(item); });
            this.refresh();
            return newItems;
        };
        /**
         * Remove an item from the command palette.
         *
         * @param item - The item to remove from the palette.
         *
         * #### Notes
         * This is a no-op if the item is not in the palette.
         */
        CommandPalette.prototype.removeItem = function (item) {
            this.removeItemAt(this._items.indexOf(item));
        };
        /**
         * Remove the item at a given index from the command palette.
         *
         * @param index - The index of the item to remove.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        CommandPalette.prototype.removeItemAt = function (index) {
            // Remove the item from the array.
            var item = algorithm.ArrayExt.removeAt(this._items, index);
            // Bail if the index is out of range.
            if (!item) {
                return;
            }
            // Refresh the search results.
            this.refresh();
        };
        /**
         * Remove all items from the command palette.
         */
        CommandPalette.prototype.clearItems = function () {
            // Bail if there is nothing to remove.
            if (this._items.length === 0) {
                return;
            }
            // Clear the array of items.
            this._items.length = 0;
            // Refresh the search results.
            this.refresh();
        };
        /**
         * Clear the search results and schedule an update.
         *
         * #### Notes
         * This should be called whenever the search results of the palette
         * should be updated.
         *
         * This is typically called automatically by the palette as needed,
         * but can be called manually if the input text is programatically
         * changed.
         *
         * The rendered results are updated asynchronously.
         */
        CommandPalette.prototype.refresh = function () {
            this._results = null;
            if (this.inputNode.value !== '') {
                var clear = this.node.getElementsByClassName('lm-close-icon')[0];
                clear.style.display = 'inherit';
            }
            else {
                var clear = this.node.getElementsByClassName('lm-close-icon')[0];
                clear.style.display = 'none';
            }
            this.update();
        };
        /**
         * Handle the DOM events for the command palette.
         *
         * @param event - The DOM event sent to the command palette.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the command palette's DOM node.
         * It should not be called directly by user code.
         */
        CommandPalette.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'click':
                    this._evtClick(event);
                    break;
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'input':
                    this.refresh();
                    break;
                case 'focus':
                case 'blur':
                    this._toggleFocused();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        CommandPalette.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('click', this);
            this.node.addEventListener('keydown', this);
            this.node.addEventListener('input', this);
            this.node.addEventListener('focus', this, true);
            this.node.addEventListener('blur', this, true);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        CommandPalette.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('click', this);
            this.node.removeEventListener('keydown', this);
            this.node.removeEventListener('input', this);
            this.node.removeEventListener('focus', this, true);
            this.node.removeEventListener('blur', this, true);
        };
        /**
         * A message handler invoked on an `'activate-request'` message.
         */
        CommandPalette.prototype.onActivateRequest = function (msg) {
            if (this.isAttached) {
                var input = this.inputNode;
                input.focus();
                input.select();
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        CommandPalette.prototype.onUpdateRequest = function (msg) {
            // Fetch the current query text and content node.
            var query = this.inputNode.value;
            var contentNode = this.contentNode;
            // Ensure the search results are generated.
            var results = this._results;
            if (!results) {
                // Generate and store the new search results.
                results = this._results = Private$a.search(this._items, query);
                // Reset the active index.
                this._activeIndex = query
                    ? algorithm.ArrayExt.findFirstIndex(results, Private$a.canActivate)
                    : -1;
            }
            // If there is no query and no results, clear the content.
            if (!query && results.length === 0) {
                virtualdom.VirtualDOM.render(null, contentNode);
                return;
            }
            // If the is a query but no results, render the empty message.
            if (query && results.length === 0) {
                var content_1 = this.renderer.renderEmptyMessage({ query: query });
                virtualdom.VirtualDOM.render(content_1, contentNode);
                return;
            }
            // Create the render content for the search results.
            var renderer = this.renderer;
            var activeIndex = this._activeIndex;
            var content = new Array(results.length);
            for (var i = 0, n = results.length; i < n; ++i) {
                var result = results[i];
                if (result.type === 'header') {
                    var indices = result.indices;
                    var category = result.category;
                    content[i] = renderer.renderHeader({ category: category, indices: indices });
                }
                else {
                    var item = result.item;
                    var indices = result.indices;
                    var active = i === activeIndex;
                    content[i] = renderer.renderItem({ item: item, indices: indices, active: active });
                }
            }
            // Render the search result content.
            virtualdom.VirtualDOM.render(content, contentNode);
            // Adjust the scroll position as needed.
            if (activeIndex < 0 || activeIndex >= results.length) {
                contentNode.scrollTop = 0;
            }
            else {
                var element = contentNode.children[activeIndex];
                domutils.ElementExt.scrollIntoViewIfNeeded(contentNode, element);
            }
        };
        /**
         * Handle the `'click'` event for the command palette.
         */
        CommandPalette.prototype._evtClick = function (event) {
            // Bail if the click is not the left button.
            if (event.button !== 0) {
                return;
            }
            // Clear input if the target is clear button
            if (event.target.classList.contains('lm-close-icon')) {
                this.inputNode.value = '';
                this.refresh();
                return;
            }
            // Find the index of the item which was clicked.
            var index = algorithm.ArrayExt.findFirstIndex(this.contentNode.children, function (node) {
                return node.contains(event.target);
            });
            // Bail if the click was not on an item.
            if (index === -1) {
                return;
            }
            // Kill the event when a content item is clicked.
            event.preventDefault();
            event.stopPropagation();
            // Execute the item if possible.
            this._execute(index);
        };
        /**
         * Handle the `'keydown'` event for the command palette.
         */
        CommandPalette.prototype._evtKeyDown = function (event) {
            if (event.altKey || event.ctrlKey || event.metaKey || event.shiftKey) {
                return;
            }
            switch (event.keyCode) {
                case 13: // Enter
                    event.preventDefault();
                    event.stopPropagation();
                    this._execute(this._activeIndex);
                    break;
                case 38: // Up Arrow
                    event.preventDefault();
                    event.stopPropagation();
                    this._activatePreviousItem();
                    break;
                case 40: // Down Arrow
                    event.preventDefault();
                    event.stopPropagation();
                    this._activateNextItem();
                    break;
            }
        };
        /**
         * Activate the next enabled command item.
         */
        CommandPalette.prototype._activateNextItem = function () {
            // Bail if there are no search results.
            if (!this._results || this._results.length === 0) {
                return;
            }
            // Find the next enabled item index.
            var ai = this._activeIndex;
            var n = this._results.length;
            var start = ai < n - 1 ? ai + 1 : 0;
            var stop = start === 0 ? n - 1 : start - 1;
            this._activeIndex = algorithm.ArrayExt.findFirstIndex(this._results, Private$a.canActivate, start, stop);
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Activate the previous enabled command item.
         */
        CommandPalette.prototype._activatePreviousItem = function () {
            // Bail if there are no search results.
            if (!this._results || this._results.length === 0) {
                return;
            }
            // Find the previous enabled item index.
            var ai = this._activeIndex;
            var n = this._results.length;
            var start = ai <= 0 ? n - 1 : ai - 1;
            var stop = start === n - 1 ? 0 : start + 1;
            this._activeIndex = algorithm.ArrayExt.findLastIndex(this._results, Private$a.canActivate, start, stop);
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Execute the command item at the given index, if possible.
         */
        CommandPalette.prototype._execute = function (index) {
            // Bail if there are no search results.
            if (!this._results) {
                return;
            }
            // Bail if the index is out of range.
            var part = this._results[index];
            if (!part) {
                return;
            }
            // Update the search text if the item is a header.
            if (part.type === 'header') {
                var input = this.inputNode;
                input.value = part.category.toLowerCase() + " ";
                input.focus();
                this.refresh();
                return;
            }
            // Bail if item is not enabled.
            if (!part.item.isEnabled) {
                return;
            }
            // Execute the item.
            this.commands.execute(part.item.command, part.item.args);
            // Clear the query text.
            this.inputNode.value = '';
            // Refresh the search results.
            this.refresh();
        };
        /**
         * Toggle the focused modifier based on the input node focus state.
         */
        CommandPalette.prototype._toggleFocused = function () {
            var focused = document.activeElement === this.inputNode;
            this.toggleClass('lm-mod-focused', focused);
            /* <DEPRECATED> */
            this.toggleClass('p-mod-focused', focused);
            /* </DEPRECATED> */
        };
        /**
         * A signal handler for generic command changes.
         */
        CommandPalette.prototype._onGenericChange = function () {
            this.refresh();
        };
        return CommandPalette;
    }(exports.Widget));
    /**
     * The namespace for the `CommandPalette` class statics.
     */
    (function (CommandPalette) {
        /**
         * The default implementation of `IRenderer`.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
            }
            /**
             * Render the virtual element for a command palette header.
             *
             * @param data - The data to use for rendering the header.
             *
             * @returns A virtual element representing the header.
             */
            Renderer.prototype.renderHeader = function (data) {
                var content = this.formatHeader(data);
                return virtualdom.h.li({
                    className: 'lm-CommandPalette-header' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-header'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the virtual element for a command palette item.
             *
             * @param data - The data to use for rendering the item.
             *
             * @returns A virtual element representing the item.
             */
            Renderer.prototype.renderItem = function (data) {
                var className = this.createItemClass(data);
                var dataset = this.createItemDataset(data);
                if (data.item.isToggleable) {
                    return virtualdom.h.li({
                        className: className,
                        dataset: dataset,
                        role: 'checkbox',
                        'aria-checked': "" + data.item.isToggled
                    }, this.renderItemIcon(data), this.renderItemContent(data), this.renderItemShortcut(data));
                }
                return virtualdom.h.li({
                    className: className,
                    dataset: dataset
                }, this.renderItemIcon(data), this.renderItemContent(data), this.renderItemShortcut(data));
            };
            /**
             * Render the empty results message for a command palette.
             *
             * @param data - The data to use for rendering the message.
             *
             * @returns A virtual element representing the message.
             */
            Renderer.prototype.renderEmptyMessage = function (data) {
                var content = this.formatEmptyMessage(data);
                return virtualdom.h.li({
                    className: 'lm-CommandPalette-emptyMessage' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-emptyMessage'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the icon for a command palette item.
             *
             * @param data - The data to use for rendering the icon.
             *
             * @returns A virtual element representing the icon.
             */
            Renderer.prototype.renderItemIcon = function (data) {
                var className = this.createIconClass(data);
                /* <DEPRECATED> */
                if (typeof data.item.icon === 'string') {
                    return virtualdom.h.div({ className: className }, data.item.iconLabel);
                }
                /* </DEPRECATED> */
                // if data.item.icon is undefined, it will be ignored
                return virtualdom.h.div({ className: className }, data.item.icon, data.item.iconLabel);
            };
            /**
             * Render the content for a command palette item.
             *
             * @param data - The data to use for rendering the content.
             *
             * @returns A virtual element representing the content.
             */
            Renderer.prototype.renderItemContent = function (data) {
                return virtualdom.h.div({
                    className: 'lm-CommandPalette-itemContent' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-itemContent'
                    /* </DEPRECATED> */
                }, this.renderItemLabel(data), this.renderItemCaption(data));
            };
            /**
             * Render the label for a command palette item.
             *
             * @param data - The data to use for rendering the label.
             *
             * @returns A virtual element representing the label.
             */
            Renderer.prototype.renderItemLabel = function (data) {
                var content = this.formatItemLabel(data);
                return virtualdom.h.div({
                    className: 'lm-CommandPalette-itemLabel' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-itemLabel'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the caption for a command palette item.
             *
             * @param data - The data to use for rendering the caption.
             *
             * @returns A virtual element representing the caption.
             */
            Renderer.prototype.renderItemCaption = function (data) {
                var content = this.formatItemCaption(data);
                return virtualdom.h.div({
                    className: 'lm-CommandPalette-itemCaption' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-itemCaption'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the shortcut for a command palette item.
             *
             * @param data - The data to use for rendering the shortcut.
             *
             * @returns A virtual element representing the shortcut.
             */
            Renderer.prototype.renderItemShortcut = function (data) {
                var content = this.formatItemShortcut(data);
                return virtualdom.h.div({
                    className: 'lm-CommandPalette-itemShortcut' +
                        /* <DEPRECATED> */
                        ' p-CommandPalette-itemShortcut'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Create the class name for the command palette item.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the command palette item.
             */
            Renderer.prototype.createItemClass = function (data) {
                // Set up the initial class name.
                var name = 'lm-CommandPalette-item';
                /* <DEPRECATED> */
                name += ' p-CommandPalette-item';
                /* </DEPRECATED> */
                // Add the boolean state classes.
                if (!data.item.isEnabled) {
                    name += ' lm-mod-disabled';
                    /* <DEPRECATED> */
                    name += ' p-mod-disabled';
                    /* </DEPRECATED> */
                }
                if (data.item.isToggled) {
                    name += ' lm-mod-toggled';
                    /* <DEPRECATED> */
                    name += ' p-mod-toggled';
                    /* </DEPRECATED> */
                }
                if (data.active) {
                    name += ' lm-mod-active';
                    /* <DEPRECATED> */
                    name += ' p-mod-active';
                    /* </DEPRECATED> */
                }
                // Add the extra class.
                var extra = data.item.className;
                if (extra) {
                    name += " " + extra;
                }
                // Return the complete class name.
                return name;
            };
            /**
             * Create the dataset for the command palette item.
             *
             * @param data - The data to use for creating the dataset.
             *
             * @returns The dataset for the command palette item.
             */
            Renderer.prototype.createItemDataset = function (data) {
                return __assign(__assign({}, data.item.dataset), { command: data.item.command });
            };
            /**
             * Create the class name for the command item icon.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the item icon.
             */
            Renderer.prototype.createIconClass = function (data) {
                var name = 'lm-CommandPalette-itemIcon';
                /* <DEPRECATED> */
                name += ' p-CommandPalette-itemIcon';
                /* </DEPRECATED> */
                var extra = data.item.iconClass;
                return extra ? name + " " + extra : name;
            };
            /**
             * Create the render content for the header node.
             *
             * @param data - The data to use for the header content.
             *
             * @returns The content to add to the header node.
             */
            Renderer.prototype.formatHeader = function (data) {
                if (!data.indices || data.indices.length === 0) {
                    return data.category;
                }
                return algorithm.StringExt.highlight(data.category, data.indices, virtualdom.h.mark);
            };
            /**
             * Create the render content for the empty message node.
             *
             * @param data - The data to use for the empty message content.
             *
             * @returns The content to add to the empty message node.
             */
            Renderer.prototype.formatEmptyMessage = function (data) {
                return "No commands found that match '" + data.query + "'";
            };
            /**
             * Create the render content for the item shortcut node.
             *
             * @param data - The data to use for the shortcut content.
             *
             * @returns The content to add to the shortcut node.
             */
            Renderer.prototype.formatItemShortcut = function (data) {
                var kb = data.item.keyBinding;
                return kb
                    ? kb.keys.map(commands.CommandRegistry.formatKeystroke).join(', ')
                    : null;
            };
            /**
             * Create the render content for the item label node.
             *
             * @param data - The data to use for the label content.
             *
             * @returns The content to add to the label node.
             */
            Renderer.prototype.formatItemLabel = function (data) {
                if (!data.indices || data.indices.length === 0) {
                    return data.item.label;
                }
                return algorithm.StringExt.highlight(data.item.label, data.indices, virtualdom.h.mark);
            };
            /**
             * Create the render content for the item caption node.
             *
             * @param data - The data to use for the caption content.
             *
             * @returns The content to add to the caption node.
             */
            Renderer.prototype.formatItemCaption = function (data) {
                return data.item.caption;
            };
            return Renderer;
        }());
        CommandPalette.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        CommandPalette.defaultRenderer = new Renderer();
    })(exports.CommandPalette || (exports.CommandPalette = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$a;
    (function (Private) {
        /**
         * Create the DOM node for a command palette.
         */
        function createNode() {
            var node = document.createElement('div');
            var search = document.createElement('div');
            var wrapper = document.createElement('div');
            var input = document.createElement('input');
            var content = document.createElement('ul');
            var clear = document.createElement('button');
            search.className = 'lm-CommandPalette-search';
            wrapper.className = 'lm-CommandPalette-wrapper';
            input.className = 'lm-CommandPalette-input';
            clear.className = 'lm-close-icon';
            content.className = 'lm-CommandPalette-content';
            /* <DEPRECATED> */
            search.classList.add('p-CommandPalette-search');
            wrapper.classList.add('p-CommandPalette-wrapper');
            input.classList.add('p-CommandPalette-input');
            content.classList.add('p-CommandPalette-content');
            /* </DEPRECATED> */
            input.spellcheck = false;
            wrapper.appendChild(input);
            wrapper.appendChild(clear);
            search.appendChild(wrapper);
            node.appendChild(search);
            node.appendChild(content);
            return node;
        }
        Private.createNode = createNode;
        /**
         * Create a new command item from a command registry and options.
         */
        function createItem(commands, options) {
            return new CommandItem(commands, options);
        }
        Private.createItem = createItem;
        /**
         * Search an array of command items for fuzzy matches.
         */
        function search(items, query) {
            // Fuzzy match the items for the query.
            var scores = matchItems(items, query);
            // Sort the items based on their score.
            scores.sort(scoreCmp);
            // Create the results for the search.
            return createResults(scores);
        }
        Private.search = search;
        /**
         * Test whether a result item can be activated.
         */
        function canActivate(result) {
            return result.type === 'item' && result.item.isEnabled;
        }
        Private.canActivate = canActivate;
        /**
         * Normalize a category for a command item.
         */
        function normalizeCategory(category) {
            return category.trim().replace(/\s+/g, ' ');
        }
        /**
         * Normalize the query text for a fuzzy search.
         */
        function normalizeQuery(text) {
            return text.replace(/\s+/g, '').toLowerCase();
        }
        /**
         * Perform a fuzzy match on an array of command items.
         */
        function matchItems(items, query) {
            // Normalize the query text to lower case with no whitespace.
            query = normalizeQuery(query);
            // Create the array to hold the scores.
            var scores = [];
            // Iterate over the items and match against the query.
            for (var i = 0, n = items.length; i < n; ++i) {
                // Ignore items which are not visible.
                var item = items[i];
                if (!item.isVisible) {
                    continue;
                }
                // If the query is empty, all items are matched by default.
                if (!query) {
                    scores.push({
                        matchType: 3 /* Default */,
                        categoryIndices: null,
                        labelIndices: null,
                        score: 0,
                        item: item
                    });
                    continue;
                }
                // Run the fuzzy search for the item and query.
                var score = fuzzySearch(item, query);
                // Ignore the item if it is not a match.
                if (!score) {
                    continue;
                }
                // Penalize disabled items.
                // TODO - push disabled items all the way down in sort cmp?
                if (!item.isEnabled) {
                    score.score += 1000;
                }
                // Add the score to the results.
                scores.push(score);
            }
            // Return the final array of scores.
            return scores;
        }
        /**
         * Perform a fuzzy search on a single command item.
         */
        function fuzzySearch(item, query) {
            // Create the source text to be searched.
            var category = item.category.toLowerCase();
            var label = item.label.toLowerCase();
            var source = category + " " + label;
            // Set up the match score and indices array.
            var score = Infinity;
            var indices = null;
            // The regex for search word boundaries
            var rgx = /\b\w/g;
            // Search the source by word boundary.
            // eslint-disable-next-line no-constant-condition
            while (true) {
                // Find the next word boundary in the source.
                var rgxMatch = rgx.exec(source);
                // Break if there is no more source context.
                if (!rgxMatch) {
                    break;
                }
                // Run the string match on the relevant substring.
                var match = algorithm.StringExt.matchSumOfDeltas(source, query, rgxMatch.index);
                // Break if there is no match.
                if (!match) {
                    break;
                }
                // Update the match if the score is better.
                if (match && match.score <= score) {
                    score = match.score;
                    indices = match.indices;
                }
            }
            // Bail if there was no match.
            if (!indices || score === Infinity) {
                return null;
            }
            // Compute the pivot index between category and label text.
            var pivot = category.length + 1;
            // Find the slice index to separate matched indices.
            var j = algorithm.ArrayExt.lowerBound(indices, pivot, function (a, b) { return a - b; });
            // Extract the matched category and label indices.
            var categoryIndices = indices.slice(0, j);
            var labelIndices = indices.slice(j);
            // Adjust the label indices for the pivot offset.
            for (var i = 0, n = labelIndices.length; i < n; ++i) {
                labelIndices[i] -= pivot;
            }
            // Handle a pure label match.
            if (categoryIndices.length === 0) {
                return {
                    matchType: 0 /* Label */,
                    categoryIndices: null,
                    labelIndices: labelIndices,
                    score: score,
                    item: item
                };
            }
            // Handle a pure category match.
            if (labelIndices.length === 0) {
                return {
                    matchType: 1 /* Category */,
                    categoryIndices: categoryIndices,
                    labelIndices: null,
                    score: score,
                    item: item
                };
            }
            // Handle a split match.
            return {
                matchType: 2 /* Split */,
                categoryIndices: categoryIndices,
                labelIndices: labelIndices,
                score: score,
                item: item
            };
        }
        /**
         * A sort comparison function for a match score.
         */
        function scoreCmp(a, b) {
            // First compare based on the match type
            var m1 = a.matchType - b.matchType;
            if (m1 !== 0) {
                return m1;
            }
            // Otherwise, compare based on the match score.
            var d1 = a.score - b.score;
            if (d1 !== 0) {
                return d1;
            }
            // Find the match index based on the match type.
            var i1 = 0;
            var i2 = 0;
            switch (a.matchType) {
                case 0 /* Label */:
                    i1 = a.labelIndices[0];
                    i2 = b.labelIndices[0];
                    break;
                case 1 /* Category */:
                case 2 /* Split */:
                    i1 = a.categoryIndices[0];
                    i2 = b.categoryIndices[0];
                    break;
            }
            // Compare based on the match index.
            if (i1 !== i2) {
                return i1 - i2;
            }
            // Otherwise, compare by category.
            var d2 = a.item.category.localeCompare(b.item.category);
            if (d2 !== 0) {
                return d2;
            }
            // Otherwise, compare by rank.
            var r1 = a.item.rank;
            var r2 = b.item.rank;
            if (r1 !== r2) {
                return r1 < r2 ? -1 : 1; // Infinity safe
            }
            // Finally, compare by label.
            return a.item.label.localeCompare(b.item.label);
        }
        /**
         * Create the results from an array of sorted scores.
         */
        function createResults(scores) {
            // Set up an array to track which scores have been visited.
            var visited = new Array(scores.length);
            algorithm.ArrayExt.fill(visited, false);
            // Set up the search results array.
            var results = [];
            // Iterate over each score in the array.
            for (var i = 0, n = scores.length; i < n; ++i) {
                // Ignore a score which has already been processed.
                if (visited[i]) {
                    continue;
                }
                // Extract the current item and indices.
                var _a = scores[i], item = _a.item, categoryIndices = _a.categoryIndices;
                // Extract the category for the current item.
                var category = item.category;
                // Add the header result for the category.
                results.push({ type: 'header', category: category, indices: categoryIndices });
                // Find the rest of the scores with the same category.
                for (var j = i; j < n; ++j) {
                    // Ignore a score which has already been processed.
                    if (visited[j]) {
                        continue;
                    }
                    // Extract the data for the current score.
                    var _b = scores[j], item_1 = _b.item, labelIndices = _b.labelIndices;
                    // Ignore an item with a different category.
                    if (item_1.category !== category) {
                        continue;
                    }
                    // Create the item result for the score.
                    results.push({ type: 'item', item: item_1, indices: labelIndices });
                    // Mark the score as processed.
                    visited[j] = true;
                }
            }
            // Return the final results.
            return results;
        }
        /**
         * A concrete implementation of `CommandPalette.IItem`.
         */
        var CommandItem = /** @class */ (function () {
            /**
             * Construct a new command item.
             */
            function CommandItem(commands, options) {
                this._commands = commands;
                this.category = normalizeCategory(options.category);
                this.command = options.command;
                this.args = options.args || coreutils.JSONExt.emptyObject;
                this.rank = options.rank !== undefined ? options.rank : Infinity;
            }
            Object.defineProperty(CommandItem.prototype, "label", {
                /**
                 * The display label for the command item.
                 */
                get: function () {
                    return this._commands.label(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "icon", {
                /**
                 * The icon renderer for the command item.
                 */
                get: function () {
                    return this._commands.icon(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "iconClass", {
                /**
                 * The icon class for the command item.
                 */
                get: function () {
                    return this._commands.iconClass(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "iconLabel", {
                /**
                 * The icon label for the command item.
                 */
                get: function () {
                    return this._commands.iconLabel(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "caption", {
                /**
                 * The display caption for the command item.
                 */
                get: function () {
                    return this._commands.caption(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "className", {
                /**
                 * The extra class name for the command item.
                 */
                get: function () {
                    return this._commands.className(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "dataset", {
                /**
                 * The dataset for the command item.
                 */
                get: function () {
                    return this._commands.dataset(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "isEnabled", {
                /**
                 * Whether the command item is enabled.
                 */
                get: function () {
                    return this._commands.isEnabled(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "isToggled", {
                /**
                 * Whether the command item is toggled.
                 */
                get: function () {
                    return this._commands.isToggled(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "isToggleable", {
                /**
                 * Whether the command item is toggleable.
                 */
                get: function () {
                    return this._commands.isToggleable(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "isVisible", {
                /**
                 * Whether the command item is visible.
                 */
                get: function () {
                    return this._commands.isVisible(this.command, this.args);
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(CommandItem.prototype, "keyBinding", {
                /**
                 * The key binding for the command item.
                 */
                get: function () {
                    var _a = this, command = _a.command, args = _a.args;
                    return (algorithm.ArrayExt.findLastValue(this._commands.keyBindings, function (kb) {
                        return kb.command === command && coreutils.JSONExt.deepEqual(kb.args, args);
                    }) || null);
                },
                enumerable: true,
                configurable: true
            });
            return CommandItem;
        }());
    })(Private$a || (Private$a = {}));

    /**
     * A widget which displays items as a canonical menu.
     */
    exports.Menu = /** @class */ (function (_super) {
        __extends(Menu, _super);
        /**
         * Construct a new menu.
         *
         * @param options - The options for initializing the menu.
         */
        function Menu(options) {
            var _this = _super.call(this, { node: Private$9.createNode() }) || this;
            _this._childIndex = -1;
            _this._activeIndex = -1;
            _this._openTimerID = 0;
            _this._closeTimerID = 0;
            _this._items = [];
            _this._childMenu = null;
            _this._parentMenu = null;
            _this._aboutToClose = new signaling.Signal(_this);
            _this._menuRequested = new signaling.Signal(_this);
            _this.addClass('lm-Menu');
            /* <DEPRECATED> */
            _this.addClass('p-Menu');
            /* </DEPRECATED> */
            _this.setFlag(exports.Widget.Flag.DisallowLayout);
            _this.commands = options.commands;
            _this.renderer = options.renderer || Menu.defaultRenderer;
            return _this;
        }
        /**
         * Dispose of the resources held by the menu.
         */
        Menu.prototype.dispose = function () {
            this.close();
            this._items.length = 0;
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(Menu.prototype, "aboutToClose", {
            /**
             * A signal emitted just before the menu is closed.
             *
             * #### Notes
             * This signal is emitted when the menu receives a `'close-request'`
             * message, just before it removes itself from the DOM.
             *
             * This signal is not emitted if the menu is already detached from
             * the DOM when it receives the `'close-request'` message.
             */
            get: function () {
                return this._aboutToClose;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "menuRequested", {
            /**
             * A signal emitted when a new menu is requested by the user.
             *
             * #### Notes
             * This signal is emitted whenever the user presses the right or left
             * arrow keys, and a submenu cannot be opened or closed in response.
             *
             * This signal is useful when implementing menu bars in order to open
             * the next or previous menu in response to a user key press.
             *
             * This signal is only emitted for the root menu in a hierarchy.
             */
            get: function () {
                return this._menuRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "parentMenu", {
            /**
             * The parent menu of the menu.
             *
             * #### Notes
             * This is `null` unless the menu is an open submenu.
             */
            get: function () {
                return this._parentMenu;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "childMenu", {
            /**
             * The child menu of the menu.
             *
             * #### Notes
             * This is `null` unless the menu has an open submenu.
             */
            get: function () {
                return this._childMenu;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "rootMenu", {
            /**
             * The root menu of the menu hierarchy.
             */
            get: function () {
                // eslint-disable-next-line @typescript-eslint/no-this-alias
                var menu = this;
                while (menu._parentMenu) {
                    menu = menu._parentMenu;
                }
                return menu;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "leafMenu", {
            /**
             * The leaf menu of the menu hierarchy.
             */
            get: function () {
                // eslint-disable-next-line @typescript-eslint/no-this-alias
                var menu = this;
                while (menu._childMenu) {
                    menu = menu._childMenu;
                }
                return menu;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "contentNode", {
            /**
             * The menu content node.
             *
             * #### Notes
             * This is the node which holds the menu item nodes.
             *
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-Menu-content')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "activeItem", {
            /**
             * Get the currently active menu item.
             */
            get: function () {
                return this._items[this._activeIndex] || null;
            },
            /**
             * Set the currently active menu item.
             *
             * #### Notes
             * If the item cannot be activated, the item will be set to `null`.
             */
            set: function (value) {
                this.activeIndex = value ? this._items.indexOf(value) : -1;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "activeIndex", {
            /**
             * Get the index of the currently active menu item.
             *
             * #### Notes
             * This will be `-1` if no menu item is active.
             */
            get: function () {
                return this._activeIndex;
            },
            /**
             * Set the index of the currently active menu item.
             *
             * #### Notes
             * If the item cannot be activated, the index will be set to `-1`.
             */
            set: function (value) {
                // Adjust the value for an out of range index.
                if (value < 0 || value >= this._items.length) {
                    value = -1;
                }
                // Ensure the item can be activated.
                if (value !== -1 && !Private$9.canActivate(this._items[value])) {
                    value = -1;
                }
                // Bail if the index will not change.
                if (this._activeIndex === value) {
                    return;
                }
                // Update the active index.
                this._activeIndex = value;
                // Make active element in focus
                if (this._activeIndex >= 0 &&
                    this.contentNode.childNodes[this._activeIndex]) {
                    this.contentNode.childNodes[this._activeIndex].focus();
                }
                // schedule an update of the items.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(Menu.prototype, "items", {
            /**
             * A read-only array of the menu items in the menu.
             */
            get: function () {
                return this._items;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Activate the next selectable item in the menu.
         *
         * #### Notes
         * If no item is selectable, the index will be set to `-1`.
         */
        Menu.prototype.activateNextItem = function () {
            var n = this._items.length;
            var ai = this._activeIndex;
            var start = ai < n - 1 ? ai + 1 : 0;
            var stop = start === 0 ? n - 1 : start - 1;
            this.activeIndex = algorithm.ArrayExt.findFirstIndex(this._items, Private$9.canActivate, start, stop);
        };
        /**
         * Activate the previous selectable item in the menu.
         *
         * #### Notes
         * If no item is selectable, the index will be set to `-1`.
         */
        Menu.prototype.activatePreviousItem = function () {
            var n = this._items.length;
            var ai = this._activeIndex;
            var start = ai <= 0 ? n - 1 : ai - 1;
            var stop = start === n - 1 ? 0 : start + 1;
            this.activeIndex = algorithm.ArrayExt.findLastIndex(this._items, Private$9.canActivate, start, stop);
        };
        /**
         * Trigger the active menu item.
         *
         * #### Notes
         * If the active item is a submenu, it will be opened and the first
         * item will be activated.
         *
         * If the active item is a command, the command will be executed.
         *
         * If the menu is not attached, this is a no-op.
         *
         * If there is no active item, this is a no-op.
         */
        Menu.prototype.triggerActiveItem = function () {
            // Bail if the menu is not attached.
            if (!this.isAttached) {
                return;
            }
            // Bail if there is no active item.
            var item = this.activeItem;
            if (!item) {
                return;
            }
            // Cancel the pending timers.
            this._cancelOpenTimer();
            this._cancelCloseTimer();
            // If the item is a submenu, open it.
            if (item.type === 'submenu') {
                this._openChildMenu(true);
                return;
            }
            // Close the root menu before executing the command.
            this.rootMenu.close();
            // Execute the command for the item.
            var command = item.command, args = item.args;
            if (this.commands.isEnabled(command, args)) {
                this.commands.execute(command, args);
            }
            else {
                console.log("Command '" + command + "' is disabled.");
            }
        };
        /**
         * Add a menu item to the end of the menu.
         *
         * @param options - The options for creating the menu item.
         *
         * @returns The menu item added to the menu.
         */
        Menu.prototype.addItem = function (options) {
            return this.insertItem(this._items.length, options);
        };
        /**
         * Insert a menu item into the menu at the specified index.
         *
         * @param index - The index at which to insert the item.
         *
         * @param options - The options for creating the menu item.
         *
         * @returns The menu item added to the menu.
         *
         * #### Notes
         * The index will be clamped to the bounds of the items.
         */
        Menu.prototype.insertItem = function (index, options) {
            // Close the menu if it's attached.
            if (this.isAttached) {
                this.close();
            }
            // Reset the active index.
            this.activeIndex = -1;
            // Clamp the insert index to the array bounds.
            var i = Math.max(0, Math.min(index, this._items.length));
            // Create the item for the options.
            var item = Private$9.createItem(this, options);
            // Insert the item into the array.
            algorithm.ArrayExt.insert(this._items, i, item);
            // Schedule an update of the items.
            this.update();
            // Return the item added to the menu.
            return item;
        };
        /**
         * Remove an item from the menu.
         *
         * @param item - The item to remove from the menu.
         *
         * #### Notes
         * This is a no-op if the item is not in the menu.
         */
        Menu.prototype.removeItem = function (item) {
            this.removeItemAt(this._items.indexOf(item));
        };
        /**
         * Remove the item at a given index from the menu.
         *
         * @param index - The index of the item to remove.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        Menu.prototype.removeItemAt = function (index) {
            // Close the menu if it's attached.
            if (this.isAttached) {
                this.close();
            }
            // Reset the active index.
            this.activeIndex = -1;
            // Remove the item from the array.
            var item = algorithm.ArrayExt.removeAt(this._items, index);
            // Bail if the index is out of range.
            if (!item) {
                return;
            }
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Remove all menu items from the menu.
         */
        Menu.prototype.clearItems = function () {
            // Close the menu if it's attached.
            if (this.isAttached) {
                this.close();
            }
            // Reset the active index.
            this.activeIndex = -1;
            // Bail if there is nothing to remove.
            if (this._items.length === 0) {
                return;
            }
            // Clear the items.
            this._items.length = 0;
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Open the menu at the specified location.
         *
         * @param x - The client X coordinate of the menu location.
         *
         * @param y - The client Y coordinate of the menu location.
         *
         * @param options - The additional options for opening the menu.
         *
         * #### Notes
         * The menu will be opened at the given location unless it will not
         * fully fit on the screen. If it will not fit, it will be adjusted
         * to fit naturally on the screen.
         *
         * This is a no-op if the menu is already attached to the DOM.
         */
        Menu.prototype.open = function (x, y, options) {
            if (options === void 0) { options = {}; }
            // Bail early if the menu is already attached.
            if (this.isAttached) {
                return;
            }
            // Extract the position options.
            var forceX = options.forceX || false;
            var forceY = options.forceY || false;
            // Open the menu as a root menu.
            Private$9.openRootMenu(this, x, y, forceX, forceY);
            // Activate the menu to accept keyboard input.
            this.activate();
        };
        /**
         * Handle the DOM events for the menu.
         *
         * @param event - The DOM event sent to the menu.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the menu's DOM nodes. It should
         * not be called directly by user code.
         */
        Menu.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'mouseup':
                    this._evtMouseUp(event);
                    break;
                case 'mousemove':
                    this._evtMouseMove(event);
                    break;
                case 'mouseenter':
                    this._evtMouseEnter(event);
                    break;
                case 'mouseleave':
                    this._evtMouseLeave(event);
                    break;
                case 'mousedown':
                    this._evtMouseDown(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        Menu.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('keydown', this);
            this.node.addEventListener('mouseup', this);
            this.node.addEventListener('mousemove', this);
            this.node.addEventListener('mouseenter', this);
            this.node.addEventListener('mouseleave', this);
            this.node.addEventListener('contextmenu', this);
            document.addEventListener('mousedown', this, true);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        Menu.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('keydown', this);
            this.node.removeEventListener('mouseup', this);
            this.node.removeEventListener('mousemove', this);
            this.node.removeEventListener('mouseenter', this);
            this.node.removeEventListener('mouseleave', this);
            this.node.removeEventListener('contextmenu', this);
            document.removeEventListener('mousedown', this, true);
        };
        /**
         * A message handler invoked on an `'activate-request'` message.
         */
        Menu.prototype.onActivateRequest = function (msg) {
            if (this.isAttached) {
                this.node.focus();
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        Menu.prototype.onUpdateRequest = function (msg) {
            var _this = this;
            var items = this._items;
            var renderer = this.renderer;
            var activeIndex = this._activeIndex;
            var collapsedFlags = Private$9.computeCollapsed(items);
            var content = new Array(items.length);
            var _loop_1 = function (i, n) {
                var item = items[i];
                var active = i === activeIndex;
                var collapsed = collapsedFlags[i];
                content[i] = renderer.renderItem({
                    item: item,
                    active: active,
                    collapsed: collapsed,
                    onfocus: function () {
                        _this.activeIndex = i;
                    }
                });
            };
            for (var i = 0, n = items.length; i < n; ++i) {
                _loop_1(i);
            }
            virtualdom.VirtualDOM.render(content, this.contentNode);
        };
        /**
         * A message handler invoked on a `'close-request'` message.
         */
        Menu.prototype.onCloseRequest = function (msg) {
            // Cancel the pending timers.
            this._cancelOpenTimer();
            this._cancelCloseTimer();
            // Reset the active index.
            this.activeIndex = -1;
            // Close any open child menu.
            var childMenu = this._childMenu;
            if (childMenu) {
                this._childIndex = -1;
                this._childMenu = null;
                childMenu._parentMenu = null;
                childMenu.close();
            }
            // Remove this menu from its parent and activate the parent.
            var parentMenu = this._parentMenu;
            if (parentMenu) {
                this._parentMenu = null;
                parentMenu._childIndex = -1;
                parentMenu._childMenu = null;
                parentMenu.activate();
            }
            // Emit the `aboutToClose` signal if the menu is attached.
            if (this.isAttached) {
                this._aboutToClose.emit(undefined);
            }
            // Finish closing the menu.
            _super.prototype.onCloseRequest.call(this, msg);
        };
        /**
         * Handle the `'keydown'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the menu node.
         */
        Menu.prototype._evtKeyDown = function (event) {
            // A menu handles all keydown events.
            event.preventDefault();
            event.stopPropagation();
            // Fetch the key code for the event.
            var kc = event.keyCode;
            // Enter
            if (kc === 13) {
                this.triggerActiveItem();
                return;
            }
            // Escape
            if (kc === 27) {
                this.close();
                return;
            }
            // Left Arrow
            if (kc === 37) {
                if (this._parentMenu) {
                    this.close();
                }
                else {
                    this._menuRequested.emit('previous');
                }
                return;
            }
            // Up Arrow
            if (kc === 38) {
                this.activatePreviousItem();
                return;
            }
            // Right Arrow
            if (kc === 39) {
                var item = this.activeItem;
                if (item && item.type === 'submenu') {
                    this.triggerActiveItem();
                }
                else {
                    this.rootMenu._menuRequested.emit('next');
                }
                return;
            }
            // Down Arrow
            if (kc === 40) {
                this.activateNextItem();
                return;
            }
            // Get the pressed key character.
            var key = keyboard.getKeyboardLayout().keyForKeydownEvent(event);
            // Bail if the key is not valid.
            if (!key) {
                return;
            }
            // Search for the next best matching mnemonic item.
            var start = this._activeIndex + 1;
            var result = Private$9.findMnemonic(this._items, key, start);
            // Handle the requested mnemonic based on the search results.
            // If exactly one mnemonic is matched, that item is triggered.
            // Otherwise, the next mnemonic is activated if available,
            // followed by the auto mnemonic if available.
            if (result.index !== -1 && !result.multiple) {
                this.activeIndex = result.index;
                this.triggerActiveItem();
            }
            else if (result.index !== -1) {
                this.activeIndex = result.index;
            }
            else if (result.auto !== -1) {
                this.activeIndex = result.auto;
            }
        };
        /**
         * Handle the `'mouseup'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the menu node.
         */
        Menu.prototype._evtMouseUp = function (event) {
            if (event.button !== 0) {
                return;
            }
            event.preventDefault();
            event.stopPropagation();
            this.triggerActiveItem();
        };
        /**
         * Handle the `'mousemove'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the menu node.
         */
        Menu.prototype._evtMouseMove = function (event) {
            // Hit test the item nodes for the item under the mouse.
            var index = algorithm.ArrayExt.findFirstIndex(this.contentNode.children, function (node) {
                return domutils.ElementExt.hitTest(node, event.clientX, event.clientY);
            });
            // Bail early if the mouse is already over the active index.
            if (index === this._activeIndex) {
                return;
            }
            // Update and coerce the active index.
            this.activeIndex = index;
            index = this.activeIndex;
            // If the index is the current child index, cancel the timers.
            if (index === this._childIndex) {
                this._cancelOpenTimer();
                this._cancelCloseTimer();
                return;
            }
            // If a child menu is currently open, start the close timer.
            if (this._childIndex !== -1) {
                this._startCloseTimer();
            }
            // Cancel the open timer to give a full delay for opening.
            this._cancelOpenTimer();
            // Bail if the active item is not a valid submenu item.
            var item = this.activeItem;
            if (!item || item.type !== 'submenu' || !item.submenu) {
                return;
            }
            // Start the open timer to open the active item submenu.
            this._startOpenTimer();
        };
        /**
         * Handle the `'mouseenter'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the menu node.
         */
        Menu.prototype._evtMouseEnter = function (event) {
            // Synchronize the active ancestor items.
            for (var menu = this._parentMenu; menu; menu = menu._parentMenu) {
                menu._cancelOpenTimer();
                menu._cancelCloseTimer();
                menu.activeIndex = menu._childIndex;
            }
        };
        /**
         * Handle the `'mouseleave'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the menu node.
         */
        Menu.prototype._evtMouseLeave = function (event) {
            // Cancel any pending submenu opening.
            this._cancelOpenTimer();
            // If there is no open child menu, just reset the active index.
            if (!this._childMenu) {
                this.activeIndex = -1;
                return;
            }
            // If the mouse is over the child menu, cancel the close timer.
            var clientX = event.clientX, clientY = event.clientY;
            if (domutils.ElementExt.hitTest(this._childMenu.node, clientX, clientY)) {
                this._cancelCloseTimer();
                return;
            }
            // Otherwise, reset the active index and start the close timer.
            this.activeIndex = -1;
            this._startCloseTimer();
        };
        /**
         * Handle the `'mousedown'` event for the menu.
         *
         * #### Notes
         * This listener is attached to the document node.
         */
        Menu.prototype._evtMouseDown = function (event) {
            // Bail if the menu is not a root menu.
            if (this._parentMenu) {
                return;
            }
            // The mouse button which is pressed is irrelevant. If the press
            // is not on a menu, the entire hierarchy is closed and the event
            // is allowed to propagate. This allows other code to act on the
            // event, such as focusing the clicked element.
            if (Private$9.hitTestMenus(this, event.clientX, event.clientY)) {
                event.preventDefault();
                event.stopPropagation();
            }
            else {
                this.close();
            }
        };
        /**
         * Open the child menu at the active index immediately.
         *
         * If a different child menu is already open, it will be closed,
         * even if the active item is not a valid submenu.
         */
        Menu.prototype._openChildMenu = function (activateFirst) {
            if (activateFirst === void 0) { activateFirst = false; }
            // If the item is not a valid submenu, close the child menu.
            var item = this.activeItem;
            if (!item || item.type !== 'submenu' || !item.submenu) {
                this._closeChildMenu();
                return;
            }
            // Do nothing if the child menu will not change.
            var submenu = item.submenu;
            if (submenu === this._childMenu) {
                return;
            }
            // Ensure the current child menu is closed.
            this._closeChildMenu();
            // Update the private child state.
            this._childMenu = submenu;
            this._childIndex = this._activeIndex;
            // Set the parent menu reference for the child.
            submenu._parentMenu = this;
            // Ensure the menu is updated and lookup the item node.
            messaging.MessageLoop.sendMessage(this, exports.Widget.Msg.UpdateRequest);
            var itemNode = this.contentNode.children[this._activeIndex];
            // Open the submenu at the active node.
            Private$9.openSubmenu(submenu, itemNode);
            // Activate the first item if desired.
            if (activateFirst) {
                submenu.activeIndex = -1;
                submenu.activateNextItem();
            }
            // Activate the child menu.
            submenu.activate();
        };
        /**
         * Close the child menu immediately.
         *
         * This is a no-op if a child menu is not open.
         */
        Menu.prototype._closeChildMenu = function () {
            if (this._childMenu) {
                this._childMenu.close();
            }
        };
        /**
         * Start the open timer, unless it is already pending.
         */
        Menu.prototype._startOpenTimer = function () {
            var _this = this;
            if (this._openTimerID === 0) {
                this._openTimerID = window.setTimeout(function () {
                    _this._openTimerID = 0;
                    _this._openChildMenu();
                }, Private$9.TIMER_DELAY);
            }
        };
        /**
         * Start the close timer, unless it is already pending.
         */
        Menu.prototype._startCloseTimer = function () {
            var _this = this;
            if (this._closeTimerID === 0) {
                this._closeTimerID = window.setTimeout(function () {
                    _this._closeTimerID = 0;
                    _this._closeChildMenu();
                }, Private$9.TIMER_DELAY);
            }
        };
        /**
         * Cancel the open timer, if the timer is pending.
         */
        Menu.prototype._cancelOpenTimer = function () {
            if (this._openTimerID !== 0) {
                clearTimeout(this._openTimerID);
                this._openTimerID = 0;
            }
        };
        /**
         * Cancel the close timer, if the timer is pending.
         */
        Menu.prototype._cancelCloseTimer = function () {
            if (this._closeTimerID !== 0) {
                clearTimeout(this._closeTimerID);
                this._closeTimerID = 0;
            }
        };
        return Menu;
    }(exports.Widget));
    /**
     * The namespace for the `Menu` class statics.
     */
    (function (Menu) {
        /**
         * The default implementation of `IRenderer`.
         *
         * #### Notes
         * Subclasses are free to reimplement rendering methods as needed.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
            }
            /**
             * Render the virtual element for a menu item.
             *
             * @param data - The data to use for rendering the item.
             *
             * @returns A virtual element representing the item.
             */
            Renderer.prototype.renderItem = function (data) {
                var className = this.createItemClass(data);
                var dataset = this.createItemDataset(data);
                var aria = this.createItemARIA(data);
                return virtualdom.h.li(__assign({ className: className,
                    dataset: dataset, tabindex: '0', onfocus: data.onfocus }, aria), this.renderIcon(data), this.renderLabel(data), this.renderShortcut(data), this.renderSubmenu(data));
            };
            /**
             * Render the icon element for a menu item.
             *
             * @param data - The data to use for rendering the icon.
             *
             * @returns A virtual element representing the item icon.
             */
            Renderer.prototype.renderIcon = function (data) {
                var className = this.createIconClass(data);
                /* <DEPRECATED> */
                if (typeof data.item.icon === 'string') {
                    return virtualdom.h.div({ className: className }, data.item.iconLabel);
                }
                /* </DEPRECATED> */
                // if data.item.icon is undefined, it will be ignored
                return virtualdom.h.div({ className: className }, data.item.icon, data.item.iconLabel);
            };
            /**
             * Render the label element for a menu item.
             *
             * @param data - The data to use for rendering the label.
             *
             * @returns A virtual element representing the item label.
             */
            Renderer.prototype.renderLabel = function (data) {
                var content = this.formatLabel(data);
                return virtualdom.h.div({
                    className: 'lm-Menu-itemLabel' +
                        /* <DEPRECATED> */
                        ' p-Menu-itemLabel'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the shortcut element for a menu item.
             *
             * @param data - The data to use for rendering the shortcut.
             *
             * @returns A virtual element representing the item shortcut.
             */
            Renderer.prototype.renderShortcut = function (data) {
                var content = this.formatShortcut(data);
                return virtualdom.h.div({
                    className: 'lm-Menu-itemShortcut' +
                        /* <DEPRECATED> */
                        ' p-Menu-itemShortcut'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Render the submenu icon element for a menu item.
             *
             * @param data - The data to use for rendering the submenu icon.
             *
             * @returns A virtual element representing the submenu icon.
             */
            Renderer.prototype.renderSubmenu = function (data) {
                return virtualdom.h.div({
                    className: 'lm-Menu-itemSubmenuIcon' +
                        /* <DEPRECATED> */
                        ' p-Menu-itemSubmenuIcon'
                    /* </DEPRECATED> */
                });
            };
            /**
             * Create the class name for the menu item.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the menu item.
             */
            Renderer.prototype.createItemClass = function (data) {
                // Setup the initial class name.
                var name = 'lm-Menu-item';
                /* <DEPRECATED> */
                name += ' p-Menu-item';
                /* </DEPRECATED> */
                // Add the boolean state classes.
                if (!data.item.isEnabled) {
                    name += ' lm-mod-disabled';
                    /* <DEPRECATED> */
                    name += ' p-mod-disabled';
                    /* </DEPRECATED> */
                }
                if (data.item.isToggled) {
                    name += ' lm-mod-toggled';
                    /* <DEPRECATED> */
                    name += ' p-mod-toggled';
                    /* </DEPRECATED> */
                }
                if (!data.item.isVisible) {
                    name += ' lm-mod-hidden';
                    /* <DEPRECATED> */
                    name += ' p-mod-hidden';
                    /* </DEPRECATED> */
                }
                if (data.active) {
                    name += ' lm-mod-active';
                    /* <DEPRECATED> */
                    name += ' p-mod-active';
                    /* </DEPRECATED> */
                }
                if (data.collapsed) {
                    name += ' lm-mod-collapsed';
                    /* <DEPRECATED> */
                    name += ' p-mod-collapsed';
                    /* </DEPRECATED> */
                }
                // Add the extra class.
                var extra = data.item.className;
                if (extra) {
                    name += " " + extra;
                }
                // Return the complete class name.
                return name;
            };
            /**
             * Create the dataset for the menu item.
             *
             * @param data - The data to use for creating the dataset.
             *
             * @returns The dataset for the menu item.
             */
            Renderer.prototype.createItemDataset = function (data) {
                var result;
                var _a = data.item, type = _a.type, command = _a.command, dataset = _a.dataset;
                if (type === 'command') {
                    result = __assign(__assign({}, dataset), { type: type, command: command });
                }
                else {
                    result = __assign(__assign({}, dataset), { type: type });
                }
                return result;
            };
            /**
             * Create the class name for the menu item icon.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the item icon.
             */
            Renderer.prototype.createIconClass = function (data) {
                var name = 'lm-Menu-itemIcon';
                /* <DEPRECATED> */
                name += ' p-Menu-itemIcon';
                /* </DEPRECATED> */
                var extra = data.item.iconClass;
                return extra ? name + " " + extra : name;
            };
            /**
             * Create the aria attributes for menu item.
             *
             * @param data - The data to use for the aria attributes.
             *
             * @returns The aria attributes object for the item.
             */
            Renderer.prototype.createItemARIA = function (data) {
                var aria = {};
                switch (data.item.type) {
                    case 'separator':
                        aria.role = 'presentation';
                        break;
                    case 'submenu':
                        aria['aria-haspopup'] = 'true';
                        if (!data.item.isEnabled) {
                            aria['aria-disabled'] = 'true';
                        }
                        break;
                    default:
                        if (!data.item.isEnabled) {
                            aria['aria-disabled'] = 'true';
                        }
                        aria.role = 'menuitem';
                }
                return aria;
            };
            /**
             * Create the render content for the label node.
             *
             * @param data - The data to use for the label content.
             *
             * @returns The content to add to the label node.
             */
            Renderer.prototype.formatLabel = function (data) {
                // Fetch the label text and mnemonic index.
                var _a = data.item, label = _a.label, mnemonic = _a.mnemonic;
                // If the index is out of range, do not modify the label.
                if (mnemonic < 0 || mnemonic >= label.length) {
                    return label;
                }
                // Split the label into parts.
                var prefix = label.slice(0, mnemonic);
                var suffix = label.slice(mnemonic + 1);
                var char = label[mnemonic];
                // Wrap the mnemonic character in a span.
                var span = virtualdom.h.span({
                    className: 'lm-Menu-itemMnemonic' +
                        /* <DEPRECATED> */
                        ' p-Menu-itemMnemonic'
                    /* </DEPRECATED> */
                }, char);
                // Return the content parts.
                return [prefix, span, suffix];
            };
            /**
             * Create the render content for the shortcut node.
             *
             * @param data - The data to use for the shortcut content.
             *
             * @returns The content to add to the shortcut node.
             */
            Renderer.prototype.formatShortcut = function (data) {
                var kb = data.item.keyBinding;
                return kb
                    ? kb.keys.map(commands.CommandRegistry.formatKeystroke).join(', ')
                    : null;
            };
            return Renderer;
        }());
        Menu.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        Menu.defaultRenderer = new Renderer();
    })(exports.Menu || (exports.Menu = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$9;
    (function (Private) {
        /**
         * The ms delay for opening and closing a submenu.
         */
        Private.TIMER_DELAY = 300;
        /**
         * The horizontal pixel overlap for an open submenu.
         */
        Private.SUBMENU_OVERLAP = 3;
        /**
         * Create the DOM node for a menu.
         */
        function createNode() {
            var node = document.createElement('div');
            var content = document.createElement('ul');
            content.className = 'lm-Menu-content';
            /* <DEPRECATED> */
            content.classList.add('p-Menu-content');
            /* </DEPRECATED> */
            node.appendChild(content);
            content.setAttribute('role', 'menu');
            node.tabIndex = 0;
            return node;
        }
        Private.createNode = createNode;
        /**
         * Test whether a menu item can be activated.
         */
        function canActivate(item) {
            return item.type !== 'separator' && item.isEnabled && item.isVisible;
        }
        Private.canActivate = canActivate;
        /**
         * Create a new menu item for an owner menu.
         */
        function createItem(owner, options) {
            return new MenuItem(owner.commands, options);
        }
        Private.createItem = createItem;
        /**
         * Hit test a menu hierarchy starting at the given root.
         */
        function hitTestMenus(menu, x, y) {
            for (var temp = menu; temp; temp = temp.childMenu) {
                if (domutils.ElementExt.hitTest(temp.node, x, y)) {
                    return true;
                }
            }
            return false;
        }
        Private.hitTestMenus = hitTestMenus;
        /**
         * Compute which extra separator items should be collapsed.
         */
        function computeCollapsed(items) {
            // Allocate the return array and fill it with `false`.
            var result = new Array(items.length);
            algorithm.ArrayExt.fill(result, false);
            // Collapse the leading separators.
            var k1 = 0;
            var n = items.length;
            for (; k1 < n; ++k1) {
                var item = items[k1];
                if (!item.isVisible) {
                    continue;
                }
                if (item.type !== 'separator') {
                    break;
                }
                result[k1] = true;
            }
            // Hide the trailing separators.
            var k2 = n - 1;
            for (; k2 >= 0; --k2) {
                var item = items[k2];
                if (!item.isVisible) {
                    continue;
                }
                if (item.type !== 'separator') {
                    break;
                }
                result[k2] = true;
            }
            // Hide the remaining consecutive separators.
            var hide = false;
            while (++k1 < k2) {
                var item = items[k1];
                if (!item.isVisible) {
                    continue;
                }
                if (item.type !== 'separator') {
                    hide = false;
                }
                else if (hide) {
                    result[k1] = true;
                }
                else {
                    hide = true;
                }
            }
            // Return the resulting flags.
            return result;
        }
        Private.computeCollapsed = computeCollapsed;
        /**
         * Open a menu as a root menu at the target location.
         */
        function openRootMenu(menu, x, y, forceX, forceY) {
            // Ensure the menu is updated before attaching and measuring.
            messaging.MessageLoop.sendMessage(menu, exports.Widget.Msg.UpdateRequest);
            // Get the current position and size of the main viewport.
            var px = window.pageXOffset;
            var py = window.pageYOffset;
            var cw = document.documentElement.clientWidth;
            var ch = document.documentElement.clientHeight;
            // Compute the maximum allowed height for the menu.
            var maxHeight = ch - (forceY ? y : 0);
            // Fetch common variables.
            var node = menu.node;
            var style = node.style;
            // Clear the menu geometry and prepare it for measuring.
            style.top = '';
            style.left = '';
            style.width = '';
            style.height = '';
            style.visibility = 'hidden';
            style.maxHeight = maxHeight + "px";
            // Attach the menu to the document.
            exports.Widget.attach(menu, document.body);
            // Measure the size of the menu.
            var _a = node.getBoundingClientRect(), width = _a.width, height = _a.height;
            // Adjust the X position of the menu to fit on-screen.
            if (!forceX && x + width > px + cw) {
                x = px + cw - width;
            }
            // Adjust the Y position of the menu to fit on-screen.
            if (!forceY && y + height > py + ch) {
                if (y > py + ch) {
                    y = py + ch - height;
                }
                else {
                    y = y - height;
                }
            }
            // Update the position of the menu to the computed position.
            style.top = Math.max(0, y) + "px";
            style.left = Math.max(0, x) + "px";
            // Finally, make the menu visible on the screen.
            style.visibility = '';
        }
        Private.openRootMenu = openRootMenu;
        /**
         * Open a menu as a submenu using an item node for positioning.
         */
        function openSubmenu(submenu, itemNode) {
            // Ensure the menu is updated before opening.
            messaging.MessageLoop.sendMessage(submenu, exports.Widget.Msg.UpdateRequest);
            // Get the current position and size of the main viewport.
            var px = window.pageXOffset;
            var py = window.pageYOffset;
            var cw = document.documentElement.clientWidth;
            var ch = document.documentElement.clientHeight;
            // Compute the maximum allowed height for the menu.
            var maxHeight = ch;
            // Fetch common variables.
            var node = submenu.node;
            var style = node.style;
            // Clear the menu geometry and prepare it for measuring.
            style.top = '';
            style.left = '';
            style.width = '';
            style.height = '';
            style.visibility = 'hidden';
            style.maxHeight = maxHeight + "px";
            // Attach the menu to the document.
            exports.Widget.attach(submenu, document.body);
            // Measure the size of the menu.
            var _a = node.getBoundingClientRect(), width = _a.width, height = _a.height;
            // Compute the box sizing for the menu.
            var box = domutils.ElementExt.boxSizing(submenu.node);
            // Get the bounding rect for the target item node.
            var itemRect = itemNode.getBoundingClientRect();
            // Compute the target X position.
            var x = itemRect.right - Private.SUBMENU_OVERLAP;
            // Adjust the X position to fit on the screen.
            if (x + width > px + cw) {
                x = itemRect.left + Private.SUBMENU_OVERLAP - width;
            }
            // Compute the target Y position.
            var y = itemRect.top - box.borderTop - box.paddingTop;
            // Adjust the Y position to fit on the screen.
            if (y + height > py + ch) {
                y = itemRect.bottom + box.borderBottom + box.paddingBottom - height;
            }
            // Update the position of the menu to the computed position.
            style.top = Math.max(0, y) + "px";
            style.left = Math.max(0, x) + "px";
            // Finally, make the menu visible on the screen.
            style.visibility = '';
        }
        Private.openSubmenu = openSubmenu;
        /**
         * Find the best matching mnemonic item.
         *
         * The search starts at the given index and wraps around.
         */
        function findMnemonic(items, key, start) {
            // Setup the result variables.
            var index = -1;
            var auto = -1;
            var multiple = false;
            // Normalize the key to upper case.
            var upperKey = key.toUpperCase();
            // Search the items from the given start index.
            for (var i = 0, n = items.length; i < n; ++i) {
                // Compute the wrapped index.
                var k = (i + start) % n;
                // Lookup the item
                var item = items[k];
                // Ignore items which cannot be activated.
                if (!canActivate(item)) {
                    continue;
                }
                // Ignore items with an empty label.
                var label = item.label;
                if (label.length === 0) {
                    continue;
                }
                // Lookup the mnemonic index for the label.
                var mn = item.mnemonic;
                // Handle a valid mnemonic index.
                if (mn >= 0 && mn < label.length) {
                    if (label[mn].toUpperCase() === upperKey) {
                        if (index === -1) {
                            index = k;
                        }
                        else {
                            multiple = true;
                        }
                    }
                    continue;
                }
                // Finally, handle the auto index if possible.
                if (auto === -1 && label[0].toUpperCase() === upperKey) {
                    auto = k;
                }
            }
            // Return the search results.
            return { index: index, multiple: multiple, auto: auto };
        }
        Private.findMnemonic = findMnemonic;
        /**
         * A concrete implementation of `Menu.IItem`.
         */
        var MenuItem = /** @class */ (function () {
            /**
             * Construct a new menu item.
             */
            function MenuItem(commands, options) {
                this._commands = commands;
                this.type = options.type || 'command';
                this.command = options.command || '';
                this.args = options.args || coreutils.JSONExt.emptyObject;
                this.submenu = options.submenu || null;
            }
            Object.defineProperty(MenuItem.prototype, "label", {
                /**
                 * The display label for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.label(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.label;
                    }
                    return '';
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "mnemonic", {
                /**
                 * The mnemonic index for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.mnemonic(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.mnemonic;
                    }
                    return -1;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "icon", {
                /**
                 * The icon renderer for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.icon(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.icon;
                    }
                    /* <DEPRECATED> */
                    // alias to icon class if not otherwise defined
                    return this.iconClass;
                    /* </DEPRECATED> */
                    /* <FUTURE>
                    return undefined;
                    </FUTURE> */
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "iconClass", {
                /**
                 * The icon class for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.iconClass(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.iconClass;
                    }
                    return '';
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "iconLabel", {
                /**
                 * The icon label for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.iconLabel(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.iconLabel;
                    }
                    return '';
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "caption", {
                /**
                 * The display caption for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.caption(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.caption;
                    }
                    return '';
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "className", {
                /**
                 * The extra class name for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.className(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.className;
                    }
                    return '';
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "dataset", {
                /**
                 * The dataset for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.dataset(this.command, this.args);
                    }
                    if (this.type === 'submenu' && this.submenu) {
                        return this.submenu.title.dataset;
                    }
                    return {};
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "isEnabled", {
                /**
                 * Whether the menu item is enabled.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.isEnabled(this.command, this.args);
                    }
                    if (this.type === 'submenu') {
                        return this.submenu !== null;
                    }
                    return true;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "isToggled", {
                /**
                 * Whether the menu item is toggled.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.isToggled(this.command, this.args);
                    }
                    return false;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "isVisible", {
                /**
                 * Whether the menu item is visible.
                 */
                get: function () {
                    if (this.type === 'command') {
                        return this._commands.isVisible(this.command, this.args);
                    }
                    if (this.type === 'submenu') {
                        return this.submenu !== null;
                    }
                    return true;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(MenuItem.prototype, "keyBinding", {
                /**
                 * The key binding for the menu item.
                 */
                get: function () {
                    if (this.type === 'command') {
                        var _a = this, command_1 = _a.command, args_1 = _a.args;
                        return (algorithm.ArrayExt.findLastValue(this._commands.keyBindings, function (kb) {
                            return kb.command === command_1 && coreutils.JSONExt.deepEqual(kb.args, args_1);
                        }) || null);
                    }
                    return null;
                },
                enumerable: true,
                configurable: true
            });
            return MenuItem;
        }());
    })(Private$9 || (Private$9 = {}));

    /**
     * An object which implements a universal context menu.
     *
     * #### Notes
     * The items shown in the context menu are determined by CSS selector
     * matching against the DOM hierarchy at the site of the mouse click.
     * This is similar in concept to how keyboard shortcuts are matched
     * in the command registry.
     */
    var ContextMenu = /** @class */ (function () {
        /**
         * Construct a new context menu.
         *
         * @param options - The options for initializing the menu.
         */
        function ContextMenu(options) {
            this._groupByTarget = true;
            this._idTick = 0;
            this._items = [];
            this._sortBySelector = true;
            var groupByTarget = options.groupByTarget, sortBySelector = options.sortBySelector, others = __rest(options, ["groupByTarget", "sortBySelector"]);
            this.menu = new exports.Menu(others);
            this._groupByTarget = groupByTarget !== false;
            this._sortBySelector = sortBySelector !== false;
        }
        /**
         * Add an item to the context menu.
         *
         * @param options - The options for creating the item.
         *
         * @returns A disposable which will remove the item from the menu.
         */
        ContextMenu.prototype.addItem = function (options) {
            var _this = this;
            // Create an item from the given options.
            var item = Private$8.createItem(options, this._idTick++);
            // Add the item to the internal array.
            this._items.push(item);
            // Return a disposable which will remove the item.
            return new disposable.DisposableDelegate(function () {
                algorithm.ArrayExt.removeFirstOf(_this._items, item);
            });
        };
        /**
         * Open the context menu in response to a `'contextmenu'` event.
         *
         * @param event - The `'contextmenu'` event of interest.
         *
         * @returns `true` if the menu was opened, or `false` if no items
         *   matched the event and the menu was not opened.
         *
         * #### Notes
         * This method will populate the context menu with items which match
         * the propagation path of the event, then open the menu at the mouse
         * position indicated by the event.
         */
        ContextMenu.prototype.open = function (event) {
            var _this = this;
            // Clear the current contents of the context menu.
            this.menu.clearItems();
            // Bail early if there are no items to match.
            if (this._items.length === 0) {
                return false;
            }
            // Find the matching items for the event.
            var items = Private$8.matchItems(this._items, event, this._groupByTarget, this._sortBySelector);
            // Bail if there are no matching items.
            if (!items || items.length === 0) {
                return false;
            }
            // Add the filtered items to the menu.
            algorithm.each(items, function (item) {
                _this.menu.addItem(item);
            });
            // Open the context menu at the current mouse position.
            this.menu.open(event.clientX, event.clientY);
            // Indicate success.
            return true;
        };
        return ContextMenu;
    }());
    /**
     * The namespace for the module implementation details.
     */
    var Private$8;
    (function (Private) {
        /**
         * Create a normalized context menu item from an options object.
         */
        function createItem(options, id) {
            var selector = validateSelector(options.selector);
            var rank = options.rank !== undefined ? options.rank : Infinity;
            return __assign(__assign({}, options), { selector: selector, rank: rank, id: id });
        }
        Private.createItem = createItem;
        /**
         * Find the items which match a context menu event.
         *
         * The results are sorted by DOM level, specificity, and rank.
         */
        function matchItems(items, event, groupByTarget, sortBySelector) {
            // Look up the target of the event.
            var target = event.target;
            // Bail if there is no target.
            if (!target) {
                return null;
            }
            // Look up the current target of the event.
            var currentTarget = event.currentTarget;
            // Bail if there is no current target.
            if (!currentTarget) {
                return null;
            }
            // There are some third party libraries that cause the `target` to
            // be detached from the DOM before lumino can process the event.
            // If that happens, search for a new target node by point. If that
            // node is still dangling, bail.
            if (!currentTarget.contains(target)) {
                target = document.elementFromPoint(event.clientX, event.clientY);
                if (!target || !currentTarget.contains(target)) {
                    return null;
                }
            }
            // Set up the result array.
            var result = [];
            // Copy the items array to allow in-place modification.
            var availableItems = items.slice();
            // Walk up the DOM hierarchy searching for matches.
            while (target !== null) {
                // Set up the match array for this DOM level.
                var matches = [];
                // Search the remaining items for matches.
                for (var i = 0, n = availableItems.length; i < n; ++i) {
                    // Fetch the item.
                    var item = availableItems[i];
                    // Skip items which are already consumed.
                    if (!item) {
                        continue;
                    }
                    // Skip items which do not match the element.
                    if (!domutils.Selector.matches(target, item.selector)) {
                        continue;
                    }
                    // Add the matched item to the result for this DOM level.
                    matches.push(item);
                    // Mark the item as consumed.
                    availableItems[i] = null;
                }
                // Sort the matches for this level and add them to the results.
                if (matches.length !== 0) {
                    if (groupByTarget) {
                        matches.sort(sortBySelector ? itemCmp : itemCmpRank);
                    }
                    result.push.apply(result, matches);
                }
                // Stop searching at the limits of the DOM range.
                if (target === currentTarget) {
                    break;
                }
                // Step to the parent DOM level.
                target = target.parentElement;
            }
            if (!groupByTarget) {
                result.sort(sortBySelector ? itemCmp : itemCmpRank);
            }
            // Return the matched and sorted results.
            return result;
        }
        Private.matchItems = matchItems;
        /**
         * Validate the selector for a menu item.
         *
         * This returns the validated selector, or throws if the selector is
         * invalid or contains commas.
         */
        function validateSelector(selector) {
            if (selector.indexOf(',') !== -1) {
                throw new Error("Selector cannot contain commas: " + selector);
            }
            if (!domutils.Selector.isValid(selector)) {
                throw new Error("Invalid selector: " + selector);
            }
            return selector;
        }
        /**
         * A sort comparison function for a context menu item by ranks.
         */
        function itemCmpRank(a, b) {
            // Sort based on rank.
            var r1 = a.rank;
            var r2 = b.rank;
            if (r1 !== r2) {
                return r1 < r2 ? -1 : 1; // Infinity-safe
            }
            // When all else fails, sort by item id.
            return a.id - b.id;
        }
        /**
         * A sort comparison function for a context menu item by selectors and ranks.
         */
        function itemCmp(a, b) {
            // Sort first based on selector specificity.
            var s1 = domutils.Selector.calculateSpecificity(a.selector);
            var s2 = domutils.Selector.calculateSpecificity(b.selector);
            if (s1 !== s2) {
                return s2 - s1;
            }
            // If specificities are equal
            return itemCmpRank(a, b);
        }
    })(Private$8 || (Private$8 = {}));

    /**
     * A widget which displays titles as a single row or column of tabs.
     *
     * #### Notes
     * If CSS transforms are used to rotate nodes for vertically oriented
     * text, then tab dragging will not work correctly. The `tabsMovable`
     * property should be set to `false` when rotating nodes from CSS.
     */
    exports.TabBar = /** @class */ (function (_super) {
        __extends(TabBar, _super);
        /**
         * Construct a new tab bar.
         *
         * @param options - The options for initializing the tab bar.
         */
        function TabBar(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { node: Private$7.createNode() }) || this;
            _this._currentIndex = -1;
            _this._titles = [];
            _this._titlesEditable = false;
            _this._previousTitle = null;
            _this._dragData = null;
            _this._addButtonEnabled = false;
            _this._tabMoved = new signaling.Signal(_this);
            _this._currentChanged = new signaling.Signal(_this);
            _this._addRequested = new signaling.Signal(_this);
            _this._tabCloseRequested = new signaling.Signal(_this);
            _this._tabDetachRequested = new signaling.Signal(_this);
            _this._tabActivateRequested = new signaling.Signal(_this);
            _this.addClass('lm-TabBar');
            /* <DEPRECATED> */
            _this.addClass('p-TabBar');
            /* </DEPRECATED> */
            _this.contentNode.setAttribute('role', 'tablist');
            _this.setFlag(exports.Widget.Flag.DisallowLayout);
            _this._document = options.document || document;
            _this.tabsMovable = options.tabsMovable || false;
            _this.titlesEditable = options.titlesEditable || false;
            _this.allowDeselect = options.allowDeselect || false;
            _this.addButtonEnabled = options.addButtonEnabled || false;
            _this.insertBehavior = options.insertBehavior || 'select-tab-if-needed';
            _this.name = options.name || '';
            _this.orientation = options.orientation || 'horizontal';
            _this.removeBehavior = options.removeBehavior || 'select-tab-after';
            _this.renderer = options.renderer || TabBar.defaultRenderer;
            return _this;
        }
        /**
         * Dispose of the resources held by the widget.
         */
        TabBar.prototype.dispose = function () {
            this._releaseMouse();
            this._titles.length = 0;
            this._previousTitle = null;
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(TabBar.prototype, "currentChanged", {
            /**
             * A signal emitted when the current tab is changed.
             *
             * #### Notes
             * This signal is emitted when the currently selected tab is changed
             * either through user or programmatic interaction.
             *
             * Notably, this signal is not emitted when the index of the current
             * tab changes due to tabs being inserted, removed, or moved. It is
             * only emitted when the actual current tab node is changed.
             */
            get: function () {
                return this._currentChanged;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "tabMoved", {
            /**
             * A signal emitted when a tab is moved by the user.
             *
             * #### Notes
             * This signal is emitted when a tab is moved by user interaction.
             *
             * This signal is not emitted when a tab is moved programmatically.
             */
            get: function () {
                return this._tabMoved;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "tabActivateRequested", {
            /**
             * A signal emitted when a tab is clicked by the user.
             *
             * #### Notes
             * If the clicked tab is not the current tab, the clicked tab will be
             * made current and the `currentChanged` signal will be emitted first.
             *
             * This signal is emitted even if the clicked tab is the current tab.
             */
            get: function () {
                return this._tabActivateRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "addRequested", {
            /**
             * A signal emitted when the tab bar add button is clicked.
             */
            get: function () {
                return this._addRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "tabCloseRequested", {
            /**
             * A signal emitted when a tab close icon is clicked.
             *
             * #### Notes
             * This signal is not emitted unless the tab title is `closable`.
             */
            get: function () {
                return this._tabCloseRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "tabDetachRequested", {
            /**
             * A signal emitted when a tab is dragged beyond the detach threshold.
             *
             * #### Notes
             * This signal is emitted when the user drags a tab with the mouse,
             * and mouse is dragged beyond the detach threshold.
             *
             * The consumer of the signal should call `releaseMouse` and remove
             * the tab in order to complete the detach.
             *
             * This signal is only emitted once per drag cycle.
             */
            get: function () {
                return this._tabDetachRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "document", {
            /**
             * The document to use with the tab bar.
             *
             * The default is the global `document` instance.
             */
            get: function () {
                return this._document;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "titlesEditable", {
            /**
             * Whether the titles can be user-edited.
             *
             */
            get: function () {
                return this._titlesEditable;
            },
            /**
             * Set whether titles can be user edited.
             *
             */
            set: function (value) {
                this._titlesEditable = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "currentTitle", {
            /**
             * Get the currently selected title.
             *
             * #### Notes
             * This will be `null` if no tab is selected.
             */
            get: function () {
                return this._titles[this._currentIndex] || null;
            },
            /**
             * Set the currently selected title.
             *
             * #### Notes
             * If the title does not exist, the title will be set to `null`.
             */
            set: function (value) {
                this.currentIndex = value ? this._titles.indexOf(value) : -1;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "currentIndex", {
            /**
             * Get the index of the currently selected tab.
             *
             * #### Notes
             * This will be `-1` if no tab is selected.
             */
            get: function () {
                return this._currentIndex;
            },
            /**
             * Set the index of the currently selected tab.
             *
             * #### Notes
             * If the value is out of range, the index will be set to `-1`.
             */
            set: function (value) {
                // Adjust for an out of range index.
                if (value < 0 || value >= this._titles.length) {
                    value = -1;
                }
                // Bail early if the index will not change.
                if (this._currentIndex === value) {
                    return;
                }
                // Look up the previous index and title.
                var pi = this._currentIndex;
                var pt = this._titles[pi] || null;
                // Look up the current index and title.
                var ci = value;
                var ct = this._titles[ci] || null;
                // Update the current index and previous title.
                this._currentIndex = ci;
                this._previousTitle = pt;
                // Schedule an update of the tabs.
                this.update();
                // Emit the current changed signal.
                this._currentChanged.emit({
                    previousIndex: pi,
                    previousTitle: pt,
                    currentIndex: ci,
                    currentTitle: ct
                });
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "name", {
            /**
             * Get the name of the tab bar.
             */
            get: function () {
                return this._name;
            },
            /**
             * Set the name of the tab bar.
             */
            set: function (value) {
                this._name = value;
                if (value) {
                    this.contentNode.setAttribute('aria-label', value);
                }
                else {
                    this.contentNode.removeAttribute('aria-label');
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "orientation", {
            /**
             * Get the orientation of the tab bar.
             *
             * #### Notes
             * This controls whether the tabs are arranged in a row or column.
             */
            get: function () {
                return this._orientation;
            },
            /**
             * Set the orientation of the tab bar.
             *
             * #### Notes
             * This controls whether the tabs are arranged in a row or column.
             */
            set: function (value) {
                // Do nothing if the orientation does not change.
                if (this._orientation === value) {
                    return;
                }
                // Release the mouse before making any changes.
                this._releaseMouse();
                // Toggle the orientation values.
                this._orientation = value;
                this.dataset['orientation'] = value;
                this.contentNode.setAttribute('aria-orientation', value);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "addButtonEnabled", {
            /**
             * Whether the add button is enabled.
             */
            get: function () {
                return this._addButtonEnabled;
            },
            /**
             * Set whether the add button is enabled.
             */
            set: function (value) {
                // Do nothing if the value does not change.
                if (this._addButtonEnabled === value) {
                    return;
                }
                this._addButtonEnabled = value;
                if (value) {
                    this.addButtonNode.classList.remove('lm-mod-hidden');
                }
                else {
                    this.addButtonNode.classList.add('lm-mod-hidden');
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "titles", {
            /**
             * A read-only array of the titles in the tab bar.
             */
            get: function () {
                return this._titles;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "contentNode", {
            /**
             * The tab bar content node.
             *
             * #### Notes
             * This is the node which holds the tab nodes.
             *
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-TabBar-content')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabBar.prototype, "addButtonNode", {
            /**
             * The tab bar add button node.
             *
             * #### Notes
             * This is the node which holds the add button.
             *
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-TabBar-addButton')[0];
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Add a tab to the end of the tab bar.
         *
         * @param value - The title which holds the data for the tab,
         *   or an options object to convert to a title.
         *
         * @returns The title object added to the tab bar.
         *
         * #### Notes
         * If the title is already added to the tab bar, it will be moved.
         */
        TabBar.prototype.addTab = function (value) {
            return this.insertTab(this._titles.length, value);
        };
        /**
         * Insert a tab into the tab bar at the specified index.
         *
         * @param index - The index at which to insert the tab.
         *
         * @param value - The title which holds the data for the tab,
         *   or an options object to convert to a title.
         *
         * @returns The title object added to the tab bar.
         *
         * #### Notes
         * The index will be clamped to the bounds of the tabs.
         *
         * If the title is already added to the tab bar, it will be moved.
         */
        TabBar.prototype.insertTab = function (index, value) {
            // Release the mouse before making any changes.
            this._releaseMouse();
            // Coerce the value to a title.
            var title = Private$7.asTitle(value);
            // Look up the index of the title.
            var i = this._titles.indexOf(title);
            // Clamp the insert index to the array bounds.
            var j = Math.max(0, Math.min(index, this._titles.length));
            // If the title is not in the array, insert it.
            if (i === -1) {
                // Insert the title into the array.
                algorithm.ArrayExt.insert(this._titles, j, title);
                // Connect to the title changed signal.
                title.changed.connect(this._onTitleChanged, this);
                // Schedule an update of the tabs.
                this.update();
                // Adjust the current index for the insert.
                this._adjustCurrentForInsert(j, title);
                // Return the title added to the tab bar.
                return title;
            }
            // Otherwise, the title exists in the array and should be moved.
            // Adjust the index if the location is at the end of the array.
            if (j === this._titles.length) {
                j--;
            }
            // Bail if there is no effective move.
            if (i === j) {
                return title;
            }
            // Move the title to the new location.
            algorithm.ArrayExt.move(this._titles, i, j);
            // Schedule an update of the tabs.
            this.update();
            // Adjust the current index for the move.
            this._adjustCurrentForMove(i, j);
            // Return the title added to the tab bar.
            return title;
        };
        /**
         * Remove a tab from the tab bar.
         *
         * @param title - The title for the tab to remove.
         *
         * #### Notes
         * This is a no-op if the title is not in the tab bar.
         */
        TabBar.prototype.removeTab = function (title) {
            this.removeTabAt(this._titles.indexOf(title));
        };
        /**
         * Remove the tab at a given index from the tab bar.
         *
         * @param index - The index of the tab to remove.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        TabBar.prototype.removeTabAt = function (index) {
            // Release the mouse before making any changes.
            this._releaseMouse();
            // Remove the title from the array.
            var title = algorithm.ArrayExt.removeAt(this._titles, index);
            // Bail if the index is out of range.
            if (!title) {
                return;
            }
            // Disconnect from the title changed signal.
            title.changed.disconnect(this._onTitleChanged, this);
            // Clear the previous title if it's being removed.
            if (title === this._previousTitle) {
                this._previousTitle = null;
            }
            // Schedule an update of the tabs.
            this.update();
            // Adjust the current index for the remove.
            this._adjustCurrentForRemove(index, title);
        };
        /**
         * Remove all tabs from the tab bar.
         */
        TabBar.prototype.clearTabs = function () {
            // Bail if there is nothing to remove.
            if (this._titles.length === 0) {
                return;
            }
            // Release the mouse before making any changes.
            this._releaseMouse();
            // Disconnect from the title changed signals.
            for (var _i = 0, _a = this._titles; _i < _a.length; _i++) {
                var title = _a[_i];
                title.changed.disconnect(this._onTitleChanged, this);
            }
            // Get the current index and title.
            var pi = this.currentIndex;
            var pt = this.currentTitle;
            // Reset the current index and previous title.
            this._currentIndex = -1;
            this._previousTitle = null;
            // Clear the title array.
            this._titles.length = 0;
            // Schedule an update of the tabs.
            this.update();
            // If no tab was selected, there's nothing else to do.
            if (pi === -1) {
                return;
            }
            // Emit the current changed signal.
            this._currentChanged.emit({
                previousIndex: pi,
                previousTitle: pt,
                currentIndex: -1,
                currentTitle: null
            });
        };
        /**
         * Release the mouse and restore the non-dragged tab positions.
         *
         * #### Notes
         * This will cause the tab bar to stop handling mouse events and to
         * restore the tabs to their non-dragged positions.
         */
        TabBar.prototype.releaseMouse = function () {
            this._releaseMouse();
        };
        /**
         * Handle the DOM events for the tab bar.
         *
         * @param event - The DOM event sent to the tab bar.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the tab bar's DOM node.
         *
         * This should not be called directly by user code.
         */
        TabBar.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'mousedown': // <DEPRECATED>
                    this._evtMouseDown(event);
                    break;
                case 'mousemove': // <DEPRECATED>
                    this._evtMouseMove(event);
                    break;
                case 'mouseup': // <DEPRECATED>
                    this._evtMouseUp(event);
                    break;
                case 'pointerdown':
                    this._evtMouseDown(event);
                    break;
                case 'pointermove':
                    this._evtMouseMove(event);
                    break;
                case 'pointerup':
                    this._evtMouseUp(event);
                    break;
                case 'dblclick':
                    this._evtDblClick(event);
                    break;
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        TabBar.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('mousedown', this); // <DEPRECATED>
            this.node.addEventListener('pointerdown', this);
            this.node.addEventListener('dblclick', this);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        TabBar.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('mousedown', this); // <DEPRECATED>
            this.node.removeEventListener('pointerdown', this);
            this.node.removeEventListener('dblclick', this);
            this._releaseMouse();
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        TabBar.prototype.onUpdateRequest = function (msg) {
            var titles = this._titles;
            var renderer = this.renderer;
            var currentTitle = this.currentTitle;
            var content = new Array(titles.length);
            for (var i = 0, n = titles.length; i < n; ++i) {
                var title = titles[i];
                var current = title === currentTitle;
                var zIndex = current ? n : n - i - 1;
                content[i] = renderer.renderTab({ title: title, current: current, zIndex: zIndex });
            }
            virtualdom.VirtualDOM.render(content, this.contentNode);
        };
        /**
         * Handle the `'dblclick'` event for the tab bar.
         */
        TabBar.prototype._evtDblClick = function (event) {
            // Do nothing if titles are not editable
            if (!this.titlesEditable) {
                return;
            }
            var tabs = this.contentNode.children;
            // Find the index of the released tab.
            var index = algorithm.ArrayExt.findFirstIndex(tabs, function (tab) {
                return domutils.ElementExt.hitTest(tab, event.clientX, event.clientY);
            });
            // Do nothing if the press is not on a tab.
            if (index === -1) {
                return;
            }
            var title = this.titles[index];
            var label = tabs[index].querySelector('.lm-TabBar-tabLabel');
            if (label && label.contains(event.target)) {
                var value = title.label || '';
                // Clear the label element
                var oldValue_1 = label.innerHTML;
                label.innerHTML = '';
                var input_1 = document.createElement('input');
                input_1.classList.add('lm-TabBar-tabInput');
                input_1.value = value;
                label.appendChild(input_1);
                var onblur_1 = function () {
                    input_1.removeEventListener('blur', onblur_1);
                    label.innerHTML = oldValue_1;
                };
                input_1.addEventListener('dblclick', function (event) {
                    return event.stopPropagation();
                });
                input_1.addEventListener('blur', onblur_1);
                input_1.addEventListener('keydown', function (event) {
                    if (event.key === 'Enter') {
                        if (input_1.value !== '') {
                            title.label = title.caption = input_1.value;
                        }
                        onblur_1();
                    }
                    else if (event.key === 'Escape') {
                        onblur_1();
                    }
                });
                input_1.select();
                input_1.focus();
                if (label.children.length > 0) {
                    label.children[0].focus();
                }
            }
        };
        /**
         * Handle the `'keydown'` event for the tab bar.
         */
        TabBar.prototype._evtKeyDown = function (event) {
            // Stop all input events during drag.
            event.preventDefault();
            event.stopPropagation();
            // Release the mouse if `Escape` is pressed.
            if (event.keyCode === 27) {
                this._releaseMouse();
            }
        };
        /**
         * Handle the `'mousedown'` event for the tab bar.
         */
        TabBar.prototype._evtMouseDown = function (event) {
            // Do nothing if it's not a left or middle mouse press.
            if (event.button !== 0 && event.button !== 1) {
                return;
            }
            // Do nothing if a drag is in progress.
            if (this._dragData) {
                return;
            }
            // Check if the add button was clicked.
            var addButtonClicked = this.addButtonEnabled &&
                this.addButtonNode.contains(event.target);
            // Lookup the tab nodes.
            var tabs = this.contentNode.children;
            // Find the index of the pressed tab.
            var index = algorithm.ArrayExt.findFirstIndex(tabs, function (tab) {
                return domutils.ElementExt.hitTest(tab, event.clientX, event.clientY);
            });
            // Do nothing if the press is not on a tab or the add button.
            if (index === -1 && !addButtonClicked) {
                return;
            }
            // Pressing on a tab stops the event propagation.
            event.preventDefault();
            event.stopPropagation();
            // Initialize the non-measured parts of the drag data.
            this._dragData = {
                tab: tabs[index],
                index: index,
                pressX: event.clientX,
                pressY: event.clientY,
                tabPos: -1,
                tabSize: -1,
                tabPressPos: -1,
                targetIndex: -1,
                tabLayout: null,
                contentRect: null,
                override: null,
                dragActive: false,
                dragAborted: false,
                detachRequested: false
            };
            // Add the document mouse up listener.
            this.document.addEventListener('mouseup', this, true); // <DEPRECATED>
            this.document.addEventListener('pointerup', this, true);
            // Do nothing else if the middle button or add button is clicked.
            if (event.button === 1 || addButtonClicked) {
                return;
            }
            // Do nothing else if the close icon is clicked.
            var icon = tabs[index].querySelector(this.renderer.closeIconSelector);
            if (icon && icon.contains(event.target)) {
                return;
            }
            // Add the extra listeners if the tabs are movable.
            if (this.tabsMovable) {
                this.document.addEventListener('mousemove', this, true); // <DEPRECATED>
                this.document.addEventListener('pointermove', this, true);
                this.document.addEventListener('keydown', this, true);
                this.document.addEventListener('contextmenu', this, true);
            }
            // Update the current index as appropriate.
            if (this.allowDeselect && this.currentIndex === index) {
                this.currentIndex = -1;
            }
            else {
                this.currentIndex = index;
            }
            // Do nothing else if there is no current tab.
            if (this.currentIndex === -1) {
                return;
            }
            // Emit the tab activate request signal.
            this._tabActivateRequested.emit({
                index: this.currentIndex,
                title: this.currentTitle
            });
        };
        /**
         * Handle the `'mousemove'` event for the tab bar.
         */
        TabBar.prototype._evtMouseMove = function (event) {
            // Do nothing if no drag is in progress.
            var data = this._dragData;
            if (!data) {
                return;
            }
            // Suppress the event during a drag.
            event.preventDefault();
            event.stopPropagation();
            // Lookup the tab nodes.
            var tabs = this.contentNode.children;
            // Bail early if the drag threshold has not been met.
            if (!data.dragActive && !Private$7.dragExceeded(data, event)) {
                return;
            }
            // Activate the drag if necessary.
            if (!data.dragActive) {
                // Fill in the rest of the drag data measurements.
                var tabRect = data.tab.getBoundingClientRect();
                if (this._orientation === 'horizontal') {
                    data.tabPos = data.tab.offsetLeft;
                    data.tabSize = tabRect.width;
                    data.tabPressPos = data.pressX - tabRect.left;
                }
                else {
                    data.tabPos = data.tab.offsetTop;
                    data.tabSize = tabRect.height;
                    data.tabPressPos = data.pressY - tabRect.top;
                }
                data.tabLayout = Private$7.snapTabLayout(tabs, this._orientation);
                data.contentRect = this.contentNode.getBoundingClientRect();
                data.override = dragdrop.Drag.overrideCursor('default');
                // Add the dragging style classes.
                data.tab.classList.add('lm-mod-dragging');
                this.addClass('lm-mod-dragging');
                /* <DEPRECATED> */
                data.tab.classList.add('p-mod-dragging');
                this.addClass('p-mod-dragging');
                /* </DEPRECATED> */
                // Mark the drag as active.
                data.dragActive = true;
            }
            // Emit the detach requested signal if the threshold is exceeded.
            if (!data.detachRequested && Private$7.detachExceeded(data, event)) {
                // Only emit the signal once per drag cycle.
                data.detachRequested = true;
                // Setup the arguments for the signal.
                var index = data.index;
                var clientX = event.clientX;
                var clientY = event.clientY;
                var tab = tabs[index];
                var title = this._titles[index];
                // Emit the tab detach requested signal.
                this._tabDetachRequested.emit({ index: index, title: title, tab: tab, clientX: clientX, clientY: clientY });
                // Bail if the signal handler aborted the drag.
                if (data.dragAborted) {
                    return;
                }
            }
            // Update the positions of the tabs.
            Private$7.layoutTabs(tabs, data, event, this._orientation);
        };
        /**
         * Handle the `'mouseup'` event for the document.
         */
        TabBar.prototype._evtMouseUp = function (event) {
            var _this = this;
            // Do nothing if it's not a left or middle mouse release.
            if (event.button !== 0 && event.button !== 1) {
                return;
            }
            // Do nothing if no drag is in progress.
            var data = this._dragData;
            if (!data) {
                return;
            }
            // Stop the event propagation.
            event.preventDefault();
            event.stopPropagation();
            // Remove the extra mouse event listeners.
            this.document.removeEventListener('mousemove', this, true); // <DEPRECATED>
            this.document.removeEventListener('mouseup', this, true); // <DEPRECATED>
            this.document.removeEventListener('pointermove', this, true);
            this.document.removeEventListener('pointerup', this, true);
            this.document.removeEventListener('keydown', this, true);
            this.document.removeEventListener('contextmenu', this, true);
            // Handle a release when the drag is not active.
            if (!data.dragActive) {
                // Clear the drag data.
                this._dragData = null;
                // Handle clicking the add button.
                var addButtonClicked = this.addButtonEnabled &&
                    this.addButtonNode.contains(event.target);
                if (addButtonClicked) {
                    this._addRequested.emit(undefined);
                    return;
                }
                // Lookup the tab nodes.
                var tabs = this.contentNode.children;
                // Find the index of the released tab.
                var index = algorithm.ArrayExt.findFirstIndex(tabs, function (tab) {
                    return domutils.ElementExt.hitTest(tab, event.clientX, event.clientY);
                });
                // Do nothing if the release is not on the original pressed tab.
                if (index !== data.index) {
                    return;
                }
                // Ignore the release if the title is not closable.
                var title = this._titles[index];
                if (!title.closable) {
                    return;
                }
                // Emit the close requested signal if the middle button is released.
                if (event.button === 1) {
                    this._tabCloseRequested.emit({ index: index, title: title });
                    return;
                }
                // Emit the close requested signal if the close icon was released.
                var icon = tabs[index].querySelector(this.renderer.closeIconSelector);
                if (icon && icon.contains(event.target)) {
                    this._tabCloseRequested.emit({ index: index, title: title });
                    return;
                }
                // Otherwise, there is nothing left to do.
                return;
            }
            // Do nothing if the left button is not released.
            if (event.button !== 0) {
                return;
            }
            // Position the tab at its final resting position.
            Private$7.finalizeTabPosition(data, this._orientation);
            // Remove the dragging class from the tab so it can be transitioned.
            data.tab.classList.remove('lm-mod-dragging');
            /* <DEPRECATED> */
            data.tab.classList.remove('p-mod-dragging');
            /* </DEPRECATED> */
            // Parse the transition duration for releasing the tab.
            var duration = Private$7.parseTransitionDuration(data.tab);
            // Complete the release on a timer to allow the tab to transition.
            setTimeout(function () {
                // Do nothing if the drag has been aborted.
                if (data.dragAborted) {
                    return;
                }
                // Clear the drag data reference.
                _this._dragData = null;
                // Reset the positions of the tabs.
                Private$7.resetTabPositions(_this.contentNode.children, _this._orientation);
                // Clear the cursor grab.
                data.override.dispose();
                // Remove the remaining dragging style.
                _this.removeClass('lm-mod-dragging');
                /* <DEPRECATED> */
                _this.removeClass('p-mod-dragging');
                /* </DEPRECATED> */
                // If the tab was not moved, there is nothing else to do.
                var i = data.index;
                var j = data.targetIndex;
                if (j === -1 || i === j) {
                    return;
                }
                // Move the title to the new locations.
                algorithm.ArrayExt.move(_this._titles, i, j);
                // Adjust the current index for the move.
                _this._adjustCurrentForMove(i, j);
                // Emit the tab moved signal.
                _this._tabMoved.emit({
                    fromIndex: i,
                    toIndex: j,
                    title: _this._titles[j]
                });
                // Update the tabs immediately to prevent flicker.
                messaging.MessageLoop.sendMessage(_this, exports.Widget.Msg.UpdateRequest);
            }, duration);
        };
        /**
         * Release the mouse and restore the non-dragged tab positions.
         */
        TabBar.prototype._releaseMouse = function () {
            // Do nothing if no drag is in progress.
            var data = this._dragData;
            if (!data) {
                return;
            }
            // Clear the drag data reference.
            this._dragData = null;
            // Remove the extra mouse listeners.
            this.document.removeEventListener('mousemove', this, true); // <DEPRECATED>
            this.document.removeEventListener('mouseup', this, true); // <DEPRECATED>
            this.document.removeEventListener('pointermove', this, true);
            this.document.removeEventListener('pointerup', this, true);
            this.document.removeEventListener('keydown', this, true);
            this.document.removeEventListener('contextmenu', this, true);
            // Indicate the drag has been aborted. This allows the mouse
            // event handlers to return early when the drag is canceled.
            data.dragAborted = true;
            // If the drag is not active, there's nothing more to do.
            if (!data.dragActive) {
                return;
            }
            // Reset the tabs to their non-dragged positions.
            Private$7.resetTabPositions(this.contentNode.children, this._orientation);
            // Clear the cursor override.
            data.override.dispose();
            // Clear the dragging style classes.
            data.tab.classList.remove('lm-mod-dragging');
            this.removeClass('lm-mod-dragging');
            /* <DEPRECATED> */
            data.tab.classList.remove('p-mod-dragging');
            this.removeClass('p-mod-dragging');
            /* </DEPRECATED> */
        };
        /**
         * Adjust the current index for a tab insert operation.
         *
         * This method accounts for the tab bar's insertion behavior when
         * adjusting the current index and emitting the changed signal.
         */
        TabBar.prototype._adjustCurrentForInsert = function (i, title) {
            // Lookup commonly used variables.
            var ct = this.currentTitle;
            var ci = this._currentIndex;
            var bh = this.insertBehavior;
            // TODO: do we need to do an update to update the aria-selected attribute?
            // Handle the behavior where the new tab is always selected,
            // or the behavior where the new tab is selected if needed.
            if (bh === 'select-tab' || (bh === 'select-tab-if-needed' && ci === -1)) {
                this._currentIndex = i;
                this._previousTitle = ct;
                this._currentChanged.emit({
                    previousIndex: ci,
                    previousTitle: ct,
                    currentIndex: i,
                    currentTitle: title
                });
                return;
            }
            // Otherwise, silently adjust the current index if needed.
            if (ci >= i) {
                this._currentIndex++;
            }
        };
        /**
         * Adjust the current index for a tab move operation.
         *
         * This method will not cause the actual current tab to change.
         * It silently adjusts the index to account for the given move.
         */
        TabBar.prototype._adjustCurrentForMove = function (i, j) {
            if (this._currentIndex === i) {
                this._currentIndex = j;
            }
            else if (this._currentIndex < i && this._currentIndex >= j) {
                this._currentIndex++;
            }
            else if (this._currentIndex > i && this._currentIndex <= j) {
                this._currentIndex--;
            }
        };
        /**
         * Adjust the current index for a tab remove operation.
         *
         * This method accounts for the tab bar's remove behavior when
         * adjusting the current index and emitting the changed signal.
         */
        TabBar.prototype._adjustCurrentForRemove = function (i, title) {
            // Lookup commonly used variables.
            var ci = this._currentIndex;
            var bh = this.removeBehavior;
            // Silently adjust the index if the current tab is not removed.
            if (ci !== i) {
                if (ci > i) {
                    this._currentIndex--;
                }
                return;
            }
            // TODO: do we need to do an update to adjust the aria-selected value?
            // No tab gets selected if the tab bar is empty.
            if (this._titles.length === 0) {
                this._currentIndex = -1;
                this._currentChanged.emit({
                    previousIndex: i,
                    previousTitle: title,
                    currentIndex: -1,
                    currentTitle: null
                });
                return;
            }
            // Handle behavior where the next sibling tab is selected.
            if (bh === 'select-tab-after') {
                this._currentIndex = Math.min(i, this._titles.length - 1);
                this._currentChanged.emit({
                    previousIndex: i,
                    previousTitle: title,
                    currentIndex: this._currentIndex,
                    currentTitle: this.currentTitle
                });
                return;
            }
            // Handle behavior where the previous sibling tab is selected.
            if (bh === 'select-tab-before') {
                this._currentIndex = Math.max(0, i - 1);
                this._currentChanged.emit({
                    previousIndex: i,
                    previousTitle: title,
                    currentIndex: this._currentIndex,
                    currentTitle: this.currentTitle
                });
                return;
            }
            // Handle behavior where the previous history tab is selected.
            if (bh === 'select-previous-tab') {
                if (this._previousTitle) {
                    this._currentIndex = this._titles.indexOf(this._previousTitle);
                    this._previousTitle = null;
                }
                else {
                    this._currentIndex = Math.min(i, this._titles.length - 1);
                }
                this._currentChanged.emit({
                    previousIndex: i,
                    previousTitle: title,
                    currentIndex: this._currentIndex,
                    currentTitle: this.currentTitle
                });
                return;
            }
            // Otherwise, no tab gets selected.
            this._currentIndex = -1;
            this._currentChanged.emit({
                previousIndex: i,
                previousTitle: title,
                currentIndex: -1,
                currentTitle: null
            });
        };
        /**
         * Handle the `changed` signal of a title object.
         */
        TabBar.prototype._onTitleChanged = function (sender) {
            this.update();
        };
        return TabBar;
    }(exports.Widget));
    /**
     * The namespace for the `TabBar` class statics.
     */
    (function (TabBar) {
        /**
         * The default implementation of `IRenderer`.
         *
         * #### Notes
         * Subclasses are free to reimplement rendering methods as needed.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
                /**
                 * A selector which matches the close icon node in a tab.
                 */
                this.closeIconSelector = '.lm-TabBar-tabCloseIcon';
                this._tabID = 0;
                this._tabKeys = new WeakMap();
            }
            /**
             * Render the virtual element for a tab.
             *
             * @param data - The data to use for rendering the tab.
             *
             * @returns A virtual element representing the tab.
             */
            Renderer.prototype.renderTab = function (data) {
                var title = data.title.caption;
                var key = this.createTabKey(data);
                var id = key;
                var style = this.createTabStyle(data);
                var className = this.createTabClass(data);
                var dataset = this.createTabDataset(data);
                var aria = this.createTabARIA(data);
                if (data.title.closable) {
                    return virtualdom.h.li(__assign({ id: id, key: key, className: className, title: title, style: style, dataset: dataset }, aria), this.renderIcon(data), this.renderLabel(data), this.renderCloseIcon(data));
                }
                else {
                    return virtualdom.h.li(__assign({ id: id, key: key, className: className, title: title, style: style, dataset: dataset }, aria), this.renderIcon(data), this.renderLabel(data));
                }
            };
            /**
             * Render the icon element for a tab.
             *
             * @param data - The data to use for rendering the tab.
             *
             * @returns A virtual element representing the tab icon.
             */
            Renderer.prototype.renderIcon = function (data) {
                var title = data.title;
                var className = this.createIconClass(data);
                /* <DEPRECATED> */
                if (typeof title.icon === 'string') {
                    return virtualdom.h.div({ className: className }, title.iconLabel);
                }
                /* </DEPRECATED> */
                // if title.icon is undefined, it will be ignored
                return virtualdom.h.div({ className: className }, title.icon, title.iconLabel);
            };
            /**
             * Render the label element for a tab.
             *
             * @param data - The data to use for rendering the tab.
             *
             * @returns A virtual element representing the tab label.
             */
            Renderer.prototype.renderLabel = function (data) {
                return virtualdom.h.div({
                    className: 'lm-TabBar-tabLabel' +
                        /* <DEPRECATED> */
                        ' p-TabBar-tabLabel'
                    /* </DEPRECATED> */
                }, data.title.label);
            };
            /**
             * Render the close icon element for a tab.
             *
             * @param data - The data to use for rendering the tab.
             *
             * @returns A virtual element representing the tab close icon.
             */
            Renderer.prototype.renderCloseIcon = function (data) {
                return virtualdom.h.div({
                    className: 'lm-TabBar-tabCloseIcon' +
                        /* <DEPRECATED> */
                        ' p-TabBar-tabCloseIcon'
                    /* </DEPRECATED> */
                });
            };
            /**
             * Create a unique render key for the tab.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The unique render key for the tab.
             *
             * #### Notes
             * This method caches the key against the tab title the first time
             * the key is generated. This enables efficient rendering of moved
             * tabs and avoids subtle hover style artifacts.
             */
            Renderer.prototype.createTabKey = function (data) {
                var key = this._tabKeys.get(data.title);
                if (key === undefined) {
                    key = "tab-key-" + this._tabID++;
                    this._tabKeys.set(data.title, key);
                }
                return key;
            };
            /**
             * Create the inline style object for a tab.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The inline style data for the tab.
             */
            Renderer.prototype.createTabStyle = function (data) {
                return { zIndex: "" + data.zIndex };
            };
            /**
             * Create the class name for the tab.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The full class name for the tab.
             */
            Renderer.prototype.createTabClass = function (data) {
                var name = 'lm-TabBar-tab';
                /* <DEPRECATED> */
                name += ' p-TabBar-tab';
                /* </DEPRECATED> */
                if (data.title.className) {
                    name += " " + data.title.className;
                }
                if (data.title.closable) {
                    name += ' lm-mod-closable';
                    /* <DEPRECATED> */
                    name += ' p-mod-closable';
                    /* </DEPRECATED> */
                }
                if (data.current) {
                    name += ' lm-mod-current';
                    /* <DEPRECATED> */
                    name += ' p-mod-current';
                    /* </DEPRECATED> */
                }
                return name;
            };
            /**
             * Create the dataset for a tab.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The dataset for the tab.
             */
            Renderer.prototype.createTabDataset = function (data) {
                return data.title.dataset;
            };
            /**
             * Create the ARIA attributes for a tab.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The ARIA attributes for the tab.
             */
            Renderer.prototype.createTabARIA = function (data) {
                return { role: 'tab', 'aria-selected': data.current.toString() };
            };
            /**
             * Create the class name for the tab icon.
             *
             * @param data - The data to use for the tab.
             *
             * @returns The full class name for the tab icon.
             */
            Renderer.prototype.createIconClass = function (data) {
                var name = 'lm-TabBar-tabIcon';
                /* <DEPRECATED> */
                name += ' p-TabBar-tabIcon';
                /* </DEPRECATED> */
                var extra = data.title.iconClass;
                return extra ? name + " " + extra : name;
            };
            return Renderer;
        }());
        TabBar.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        TabBar.defaultRenderer = new Renderer();
        /**
         * A selector which matches the add button node in the tab bar.
         */
        TabBar.addButtonSelector = '.lm-TabBar-addButton';
    })(exports.TabBar || (exports.TabBar = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$7;
    (function (Private) {
        /**
         * The start drag distance threshold.
         */
        Private.DRAG_THRESHOLD = 5;
        /**
         * The detach distance threshold.
         */
        Private.DETACH_THRESHOLD = 20;
        /**
         * Create the DOM node for a tab bar.
         */
        function createNode() {
            var node = document.createElement('div');
            var content = document.createElement('ul');
            content.setAttribute('role', 'tablist');
            content.className = 'lm-TabBar-content';
            /* <DEPRECATED> */
            content.classList.add('p-TabBar-content');
            /* </DEPRECATED> */
            node.appendChild(content);
            var add = document.createElement('div');
            add.className = 'lm-TabBar-addButton lm-mod-hidden';
            node.appendChild(add);
            return node;
        }
        Private.createNode = createNode;
        /**
         * Coerce a title or options into a real title.
         */
        function asTitle(value) {
            return value instanceof Title ? value : new Title(value);
        }
        Private.asTitle = asTitle;
        /**
         * Parse the transition duration for a tab node.
         */
        function parseTransitionDuration(tab) {
            var style = window.getComputedStyle(tab);
            return 1000 * (parseFloat(style.transitionDuration) || 0);
        }
        Private.parseTransitionDuration = parseTransitionDuration;
        /**
         * Get a snapshot of the current tab layout values.
         */
        function snapTabLayout(tabs, orientation) {
            var layout = new Array(tabs.length);
            for (var i = 0, n = tabs.length; i < n; ++i) {
                var node = tabs[i];
                var style = window.getComputedStyle(node);
                if (orientation === 'horizontal') {
                    layout[i] = {
                        pos: node.offsetLeft,
                        size: node.offsetWidth,
                        margin: parseFloat(style.marginLeft) || 0
                    };
                }
                else {
                    layout[i] = {
                        pos: node.offsetTop,
                        size: node.offsetHeight,
                        margin: parseFloat(style.marginTop) || 0
                    };
                }
            }
            return layout;
        }
        Private.snapTabLayout = snapTabLayout;
        /**
         * Test if the event exceeds the drag threshold.
         */
        function dragExceeded(data, event) {
            var dx = Math.abs(event.clientX - data.pressX);
            var dy = Math.abs(event.clientY - data.pressY);
            return dx >= Private.DRAG_THRESHOLD || dy >= Private.DRAG_THRESHOLD;
        }
        Private.dragExceeded = dragExceeded;
        /**
         * Test if the event exceeds the drag detach threshold.
         */
        function detachExceeded(data, event) {
            var rect = data.contentRect;
            return (event.clientX < rect.left - Private.DETACH_THRESHOLD ||
                event.clientX >= rect.right + Private.DETACH_THRESHOLD ||
                event.clientY < rect.top - Private.DETACH_THRESHOLD ||
                event.clientY >= rect.bottom + Private.DETACH_THRESHOLD);
        }
        Private.detachExceeded = detachExceeded;
        /**
         * Update the relative tab positions and computed target index.
         */
        function layoutTabs(tabs, data, event, orientation) {
            // Compute the orientation-sensitive values.
            var pressPos;
            var localPos;
            var clientPos;
            var clientSize;
            if (orientation === 'horizontal') {
                pressPos = data.pressX;
                localPos = event.clientX - data.contentRect.left;
                clientPos = event.clientX;
                clientSize = data.contentRect.width;
            }
            else {
                pressPos = data.pressY;
                localPos = event.clientY - data.contentRect.top;
                clientPos = event.clientY;
                clientSize = data.contentRect.height;
            }
            // Compute the target data.
            var targetIndex = data.index;
            var targetPos = localPos - data.tabPressPos;
            var targetEnd = targetPos + data.tabSize;
            // Update the relative tab positions.
            for (var i = 0, n = tabs.length; i < n; ++i) {
                var pxPos = void 0;
                var layout = data.tabLayout[i];
                var threshold = layout.pos + (layout.size >> 1);
                if (i < data.index && targetPos < threshold) {
                    pxPos = data.tabSize + data.tabLayout[i + 1].margin + "px";
                    targetIndex = Math.min(targetIndex, i);
                }
                else if (i > data.index && targetEnd > threshold) {
                    pxPos = -data.tabSize - layout.margin + "px";
                    targetIndex = Math.max(targetIndex, i);
                }
                else if (i === data.index) {
                    var ideal = clientPos - pressPos;
                    var limit = clientSize - (data.tabPos + data.tabSize);
                    pxPos = Math.max(-data.tabPos, Math.min(ideal, limit)) + "px";
                }
                else {
                    pxPos = '';
                }
                if (orientation === 'horizontal') {
                    tabs[i].style.left = pxPos;
                }
                else {
                    tabs[i].style.top = pxPos;
                }
            }
            // Update the computed target index.
            data.targetIndex = targetIndex;
        }
        Private.layoutTabs = layoutTabs;
        /**
         * Position the drag tab at its final resting relative position.
         */
        function finalizeTabPosition(data, orientation) {
            // Compute the orientation-sensitive client size.
            var clientSize;
            if (orientation === 'horizontal') {
                clientSize = data.contentRect.width;
            }
            else {
                clientSize = data.contentRect.height;
            }
            // Compute the ideal final tab position.
            var ideal;
            if (data.targetIndex === data.index) {
                ideal = 0;
            }
            else if (data.targetIndex > data.index) {
                var tgt = data.tabLayout[data.targetIndex];
                ideal = tgt.pos + tgt.size - data.tabSize - data.tabPos;
            }
            else {
                var tgt = data.tabLayout[data.targetIndex];
                ideal = tgt.pos - data.tabPos;
            }
            // Compute the tab position limit.
            var limit = clientSize - (data.tabPos + data.tabSize);
            var final = Math.max(-data.tabPos, Math.min(ideal, limit));
            // Set the final orientation-sensitive position.
            if (orientation === 'horizontal') {
                data.tab.style.left = final + "px";
            }
            else {
                data.tab.style.top = final + "px";
            }
        }
        Private.finalizeTabPosition = finalizeTabPosition;
        /**
         * Reset the relative positions of the given tabs.
         */
        function resetTabPositions(tabs, orientation) {
            algorithm.each(tabs, function (tab) {
                if (orientation === 'horizontal') {
                    tab.style.left = '';
                }
                else {
                    tab.style.top = '';
                }
            });
        }
        Private.resetTabPositions = resetTabPositions;
    })(Private$7 || (Private$7 = {}));

    /**
     * A layout which provides a flexible docking arrangement.
     *
     * #### Notes
     * The consumer of this layout is responsible for handling all signals
     * from the generated tab bars and managing the visibility of widgets
     * and tab bars as needed.
     */
    var DockLayout = /** @class */ (function (_super) {
        __extends(DockLayout, _super);
        /**
         * Construct a new dock layout.
         *
         * @param options - The options for initializing the layout.
         */
        function DockLayout(options) {
            var _this = _super.call(this) || this;
            _this._spacing = 4;
            _this._dirty = false;
            _this._root = null;
            _this._box = null;
            _this._items = new Map();
            _this.renderer = options.renderer;
            if (options.spacing !== undefined) {
                _this._spacing = Utils$1.clampDimension(options.spacing);
            }
            _this._document = options.document || document;
            _this._hiddenMode =
                options.hiddenMode !== undefined
                    ? options.hiddenMode
                    : exports.Widget.HiddenMode.Display;
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         *
         * #### Notes
         * This will clear and dispose all widgets in the layout.
         */
        DockLayout.prototype.dispose = function () {
            // Get an iterator over the widgets in the layout.
            var widgets = this.iter();
            // Dispose of the layout items.
            this._items.forEach(function (item) {
                item.dispose();
            });
            // Clear the layout state before disposing the widgets.
            this._box = null;
            this._root = null;
            this._items.clear();
            // Dispose of the widgets contained in the old layout root.
            algorithm.each(widgets, function (widget) {
                widget.dispose();
            });
            // Dispose of the base class.
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(DockLayout.prototype, "hiddenMode", {
            /**
             * The method for hiding child widgets.
             *
             * #### Notes
             * If there is only one child widget, `Display` hiding mode will be used
             * regardless of this setting.
             */
            get: function () {
                return this._hiddenMode;
            },
            set: function (v) {
                var _this = this;
                if (this._hiddenMode === v) {
                    return;
                }
                this._hiddenMode = v;
                algorithm.each(this.tabBars(), function (bar) {
                    if (bar.titles.length > 1) {
                        bar.titles.forEach(function (title) {
                            title.owner.hiddenMode = _this._hiddenMode;
                        });
                    }
                });
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockLayout.prototype, "spacing", {
            /**
             * Get the inter-element spacing for the dock layout.
             */
            get: function () {
                return this._spacing;
            },
            /**
             * Set the inter-element spacing for the dock layout.
             */
            set: function (value) {
                value = Utils$1.clampDimension(value);
                if (this._spacing === value) {
                    return;
                }
                this._spacing = value;
                if (!this.parent) {
                    return;
                }
                this.parent.fit();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockLayout.prototype, "isEmpty", {
            /**
             * Whether the dock layout is empty.
             */
            get: function () {
                return this._root === null;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Create an iterator over all widgets in the layout.
         *
         * @returns A new iterator over the widgets in the layout.
         *
         * #### Notes
         * This iterator includes the generated tab bars.
         */
        DockLayout.prototype.iter = function () {
            return this._root ? this._root.iterAllWidgets() : algorithm.empty();
        };
        /**
         * Create an iterator over the user widgets in the layout.
         *
         * @returns A new iterator over the user widgets in the layout.
         *
         * #### Notes
         * This iterator does not include the generated tab bars.
         */
        DockLayout.prototype.widgets = function () {
            return this._root ? this._root.iterUserWidgets() : algorithm.empty();
        };
        /**
         * Create an iterator over the selected widgets in the layout.
         *
         * @returns A new iterator over the selected user widgets.
         *
         * #### Notes
         * This iterator yields the widgets corresponding to the current tab
         * of each tab bar in the layout.
         */
        DockLayout.prototype.selectedWidgets = function () {
            return this._root ? this._root.iterSelectedWidgets() : algorithm.empty();
        };
        /**
         * Create an iterator over the tab bars in the layout.
         *
         * @returns A new iterator over the tab bars in the layout.
         *
         * #### Notes
         * This iterator does not include the user widgets.
         */
        DockLayout.prototype.tabBars = function () {
            return this._root ? this._root.iterTabBars() : algorithm.empty();
        };
        /**
         * Create an iterator over the handles in the layout.
         *
         * @returns A new iterator over the handles in the layout.
         */
        DockLayout.prototype.handles = function () {
            return this._root ? this._root.iterHandles() : algorithm.empty();
        };
        /**
         * Move a handle to the given offset position.
         *
         * @param handle - The handle to move.
         *
         * @param offsetX - The desired offset X position of the handle.
         *
         * @param offsetY - The desired offset Y position of the handle.
         *
         * #### Notes
         * If the given handle is not contained in the layout, this is no-op.
         *
         * The handle will be moved as close as possible to the desired
         * position without violating any of the layout constraints.
         *
         * Only one of the coordinates is used depending on the orientation
         * of the handle. This method accepts both coordinates to make it
         * easy to invoke from a mouse move event without needing to know
         * the handle orientation.
         */
        DockLayout.prototype.moveHandle = function (handle, offsetX, offsetY) {
            // Bail early if there is no root or if the handle is hidden.
            var hidden = handle.classList.contains('lm-mod-hidden');
            /* <DEPRECATED> */
            hidden = hidden || handle.classList.contains('p-mod-hidden');
            /* </DEPRECATED> */
            if (!this._root || hidden) {
                return;
            }
            // Lookup the split node for the handle.
            var data = this._root.findSplitNode(handle);
            if (!data) {
                return;
            }
            // Compute the desired delta movement for the handle.
            var delta;
            if (data.node.orientation === 'horizontal') {
                delta = offsetX - handle.offsetLeft;
            }
            else {
                delta = offsetY - handle.offsetTop;
            }
            // Bail if there is no handle movement.
            if (delta === 0) {
                return;
            }
            // Prevent sibling resizing unless needed.
            data.node.holdSizes();
            // Adjust the sizers to reflect the handle movement.
            exports.BoxEngine.adjust(data.node.sizers, data.index, delta);
            // Update the layout of the widgets.
            if (this.parent) {
                this.parent.update();
            }
        };
        /**
         * Save the current configuration of the dock layout.
         *
         * @returns A new config object for the current layout state.
         *
         * #### Notes
         * The return value can be provided to the `restoreLayout` method
         * in order to restore the layout to its current configuration.
         */
        DockLayout.prototype.saveLayout = function () {
            // Bail early if there is no root.
            if (!this._root) {
                return { main: null };
            }
            // Hold the current sizes in the layout tree.
            this._root.holdAllSizes();
            // Return the layout config.
            return { main: this._root.createConfig() };
        };
        /**
         * Restore the layout to a previously saved configuration.
         *
         * @param config - The layout configuration to restore.
         *
         * #### Notes
         * Widgets which currently belong to the layout but which are not
         * contained in the config will be unparented.
         */
        DockLayout.prototype.restoreLayout = function (config) {
            var _this = this;
            // Create the widget set for validating the config.
            var widgetSet = new Set();
            // Normalize the main area config and collect the widgets.
            var mainConfig;
            if (config.main) {
                mainConfig = Private$6.normalizeAreaConfig(config.main, widgetSet);
            }
            else {
                mainConfig = null;
            }
            // Create iterators over the old content.
            var oldWidgets = this.widgets();
            var oldTabBars = this.tabBars();
            var oldHandles = this.handles();
            // Clear the root before removing the old content.
            this._root = null;
            // Unparent the old widgets which are not in the new config.
            algorithm.each(oldWidgets, function (widget) {
                if (!widgetSet.has(widget)) {
                    widget.parent = null;
                }
            });
            // Dispose of the old tab bars.
            algorithm.each(oldTabBars, function (tabBar) {
                tabBar.dispose();
            });
            // Remove the old handles.
            algorithm.each(oldHandles, function (handle) {
                if (handle.parentNode) {
                    handle.parentNode.removeChild(handle);
                }
            });
            // Reparent the new widgets to the current parent.
            widgetSet.forEach(function (widget) {
                widget.parent = _this.parent;
            });
            // Create the root node for the new config.
            if (mainConfig) {
                this._root = Private$6.realizeAreaConfig(mainConfig, {
                    // Ignoring optional `document` argument as we must reuse `this._document`
                    createTabBar: function (document) {
                        return _this._createTabBar();
                    },
                    createHandle: function () { return _this._createHandle(); }
                }, this._document);
            }
            else {
                this._root = null;
            }
            // If there is no parent, there is nothing more to do.
            if (!this.parent) {
                return;
            }
            // Attach the new widgets to the parent.
            widgetSet.forEach(function (widget) {
                _this.attachWidget(widget);
            });
            // Post a fit request to the parent.
            this.parent.fit();
        };
        /**
         * Add a widget to the dock layout.
         *
         * @param widget - The widget to add to the dock layout.
         *
         * @param options - The additional options for adding the widget.
         *
         * #### Notes
         * The widget will be moved if it is already contained in the layout.
         *
         * An error will be thrown if the reference widget is invalid.
         */
        DockLayout.prototype.addWidget = function (widget, options) {
            if (options === void 0) { options = {}; }
            // Parse the options.
            var ref = options.ref || null;
            var mode = options.mode || 'tab-after';
            // Find the tab node which holds the reference widget.
            var refNode = null;
            if (this._root && ref) {
                refNode = this._root.findTabNode(ref);
            }
            // Throw an error if the reference widget is invalid.
            if (ref && !refNode) {
                throw new Error('Reference widget is not in the layout.');
            }
            // Reparent the widget to the current layout parent.
            widget.parent = this.parent;
            // Insert the widget according to the insert mode.
            switch (mode) {
                case 'tab-after':
                    this._insertTab(widget, ref, refNode, true);
                    break;
                case 'tab-before':
                    this._insertTab(widget, ref, refNode, false);
                    break;
                case 'split-top':
                    this._insertSplit(widget, ref, refNode, 'vertical', false);
                    break;
                case 'split-left':
                    this._insertSplit(widget, ref, refNode, 'horizontal', false);
                    break;
                case 'split-right':
                    this._insertSplit(widget, ref, refNode, 'horizontal', true);
                    break;
                case 'split-bottom':
                    this._insertSplit(widget, ref, refNode, 'vertical', true);
                    break;
            }
            // Do nothing else if there is no parent widget.
            if (!this.parent) {
                return;
            }
            // Ensure the widget is attached to the parent widget.
            this.attachWidget(widget);
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Remove a widget from the layout.
         *
         * @param widget - The widget to remove from the layout.
         *
         * #### Notes
         * A widget is automatically removed from the layout when its `parent`
         * is set to `null`. This method should only be invoked directly when
         * removing a widget from a layout which has yet to be installed on a
         * parent widget.
         *
         * This method does *not* modify the widget's `parent`.
         */
        DockLayout.prototype.removeWidget = function (widget) {
            // Remove the widget from its current layout location.
            this._removeWidget(widget);
            // Do nothing else if there is no parent widget.
            if (!this.parent) {
                return;
            }
            // Detach the widget from the parent widget.
            this.detachWidget(widget);
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Find the tab area which contains the given client position.
         *
         * @param clientX - The client X position of interest.
         *
         * @param clientY - The client Y position of interest.
         *
         * @returns The geometry of the tab area at the given position, or
         *   `null` if there is no tab area at the given position.
         */
        DockLayout.prototype.hitTestTabAreas = function (clientX, clientY) {
            // Bail early if hit testing cannot produce valid results.
            if (!this._root || !this.parent || !this.parent.isVisible) {
                return null;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Convert from client to local coordinates.
            var rect = this.parent.node.getBoundingClientRect();
            var x = clientX - rect.left - this._box.borderLeft;
            var y = clientY - rect.top - this._box.borderTop;
            // Find the tab layout node at the local position.
            var tabNode = this._root.hitTestTabNodes(x, y);
            // Bail if a tab layout node was not found.
            if (!tabNode) {
                return null;
            }
            // Extract the data from the tab node.
            var tabBar = tabNode.tabBar, top = tabNode.top, left = tabNode.left, width = tabNode.width, height = tabNode.height;
            // Compute the right and bottom edges of the tab area.
            var borderWidth = this._box.borderLeft + this._box.borderRight;
            var borderHeight = this._box.borderTop + this._box.borderBottom;
            var right = rect.width - borderWidth - (left + width);
            var bottom = rect.height - borderHeight - (top + height);
            // Return the hit test results.
            return { tabBar: tabBar, x: x, y: y, top: top, left: left, right: right, bottom: bottom, width: width, height: height };
        };
        /**
         * Perform layout initialization which requires the parent widget.
         */
        DockLayout.prototype.init = function () {
            var _this = this;
            // Perform superclass initialization.
            _super.prototype.init.call(this);
            // Attach each widget to the parent.
            algorithm.each(this, function (widget) {
                _this.attachWidget(widget);
            });
            // Attach each handle to the parent.
            algorithm.each(this.handles(), function (handle) {
                _this.parent.node.appendChild(handle);
            });
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Attach the widget to the layout parent widget.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This is a no-op if the widget is already attached.
         */
        DockLayout.prototype.attachWidget = function (widget) {
            // Do nothing if the widget is already attached.
            if (this.parent.node === widget.node.parentNode) {
                return;
            }
            // Create the layout item for the widget.
            this._items.set(widget, new LayoutItem(widget));
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget's node to the parent.
            this.parent.node.appendChild(widget.node);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
        };
        /**
         * Detach the widget from the layout parent widget.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This is a no-op if the widget is not attached.
         */
        DockLayout.prototype.detachWidget = function (widget) {
            // Do nothing if the widget is not attached.
            if (this.parent.node !== widget.node.parentNode) {
                return;
            }
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Delete the layout item for the widget.
            var item = this._items.get(widget);
            if (item) {
                this._items.delete(widget);
                item.dispose();
            }
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         */
        DockLayout.prototype.onBeforeShow = function (msg) {
            _super.prototype.onBeforeShow.call(this, msg);
            this.parent.update();
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        DockLayout.prototype.onBeforeAttach = function (msg) {
            _super.prototype.onBeforeAttach.call(this, msg);
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-shown'` message.
         */
        DockLayout.prototype.onChildShown = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         */
        DockLayout.prototype.onChildHidden = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'resize'` message.
         */
        DockLayout.prototype.onResize = function (msg) {
            if (this.parent.isVisible) {
                this._update(msg.width, msg.height);
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        DockLayout.prototype.onUpdateRequest = function (msg) {
            if (this.parent.isVisible) {
                this._update(-1, -1);
            }
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         */
        DockLayout.prototype.onFitRequest = function (msg) {
            if (this.parent.isAttached) {
                this._fit();
            }
        };
        /**
         * Remove the specified widget from the layout structure.
         *
         * #### Notes
         * This is a no-op if the widget is not in the layout tree.
         *
         * This does not detach the widget from the parent node.
         */
        DockLayout.prototype._removeWidget = function (widget) {
            // Bail early if there is no layout root.
            if (!this._root) {
                return;
            }
            // Find the tab node which contains the given widget.
            var tabNode = this._root.findTabNode(widget);
            // Bail early if the tab node is not found.
            if (!tabNode) {
                return;
            }
            Private$6.removeAria(widget);
            // If there are multiple tabs, just remove the widget's tab.
            if (tabNode.tabBar.titles.length > 1) {
                tabNode.tabBar.removeTab(widget.title);
                if (this._hiddenMode === exports.Widget.HiddenMode.Scale &&
                    tabNode.tabBar.titles.length == 1) {
                    var existingWidget = tabNode.tabBar.titles[0].owner;
                    existingWidget.hiddenMode = exports.Widget.HiddenMode.Display;
                }
                return;
            }
            // Otherwise, the tab node needs to be removed...
            // Dispose the tab bar.
            tabNode.tabBar.dispose();
            // Handle the case where the tab node is the root.
            if (this._root === tabNode) {
                this._root = null;
                return;
            }
            // Otherwise, remove the tab node from its parent...
            // Prevent widget resizing unless needed.
            this._root.holdAllSizes();
            // Clear the parent reference on the tab node.
            var splitNode = tabNode.parent;
            tabNode.parent = null;
            // Remove the tab node from its parent split node.
            var i = algorithm.ArrayExt.removeFirstOf(splitNode.children, tabNode);
            var handle = algorithm.ArrayExt.removeAt(splitNode.handles, i);
            algorithm.ArrayExt.removeAt(splitNode.sizers, i);
            // Remove the handle from its parent DOM node.
            if (handle.parentNode) {
                handle.parentNode.removeChild(handle);
            }
            // If there are multiple children, just update the handles.
            if (splitNode.children.length > 1) {
                splitNode.syncHandles();
                return;
            }
            // Otherwise, the split node also needs to be removed...
            // Clear the parent reference on the split node.
            var maybeParent = splitNode.parent;
            splitNode.parent = null;
            // Lookup the remaining child node and handle.
            var childNode = splitNode.children[0];
            var childHandle = splitNode.handles[0];
            // Clear the split node data.
            splitNode.children.length = 0;
            splitNode.handles.length = 0;
            splitNode.sizers.length = 0;
            // Remove the child handle from its parent node.
            if (childHandle.parentNode) {
                childHandle.parentNode.removeChild(childHandle);
            }
            // Handle the case where the split node is the root.
            if (this._root === splitNode) {
                childNode.parent = null;
                this._root = childNode;
                return;
            }
            // Otherwise, move the child node to the parent node...
            var parentNode = maybeParent;
            // Lookup the index of the split node.
            var j = parentNode.children.indexOf(splitNode);
            // Handle the case where the child node is a tab node.
            if (childNode instanceof Private$6.TabLayoutNode) {
                childNode.parent = parentNode;
                parentNode.children[j] = childNode;
                return;
            }
            // Remove the split data from the parent.
            var splitHandle = algorithm.ArrayExt.removeAt(parentNode.handles, j);
            algorithm.ArrayExt.removeAt(parentNode.children, j);
            algorithm.ArrayExt.removeAt(parentNode.sizers, j);
            // Remove the handle from its parent node.
            if (splitHandle.parentNode) {
                splitHandle.parentNode.removeChild(splitHandle);
            }
            // The child node and the split parent node will have the same
            // orientation. Merge the grand-children with the parent node.
            for (var i_1 = 0, n = childNode.children.length; i_1 < n; ++i_1) {
                var gChild = childNode.children[i_1];
                var gHandle = childNode.handles[i_1];
                var gSizer = childNode.sizers[i_1];
                algorithm.ArrayExt.insert(parentNode.children, j + i_1, gChild);
                algorithm.ArrayExt.insert(parentNode.handles, j + i_1, gHandle);
                algorithm.ArrayExt.insert(parentNode.sizers, j + i_1, gSizer);
                gChild.parent = parentNode;
            }
            // Clear the child node.
            childNode.children.length = 0;
            childNode.handles.length = 0;
            childNode.sizers.length = 0;
            childNode.parent = null;
            // Sync the handles on the parent node.
            parentNode.syncHandles();
        };
        /**
         * Insert a widget next to an existing tab.
         *
         * #### Notes
         * This does not attach the widget to the parent widget.
         */
        DockLayout.prototype._insertTab = function (widget, ref, refNode, after) {
            // Do nothing if the tab is inserted next to itself.
            if (widget === ref) {
                return;
            }
            // Create the root if it does not exist.
            if (!this._root) {
                var tabNode = new Private$6.TabLayoutNode(this._createTabBar());
                tabNode.tabBar.addTab(widget.title);
                this._root = tabNode;
                Private$6.addAria(widget, tabNode.tabBar);
                return;
            }
            // Use the first tab node as the ref node if needed.
            if (!refNode) {
                refNode = this._root.findFirstTabNode();
            }
            // If the widget is not contained in the ref node, ensure it is
            // removed from the layout and hidden before being added again.
            if (refNode.tabBar.titles.indexOf(widget.title) === -1) {
                this._removeWidget(widget);
                widget.hide();
            }
            // Lookup the target index for inserting the tab.
            var index;
            if (ref) {
                index = refNode.tabBar.titles.indexOf(ref.title);
            }
            else {
                index = refNode.tabBar.currentIndex;
            }
            // Using transform create an additional layer in the pixel pipeline
            // to limit the number of layer, it is set only if there is more than one widget.
            if (this._hiddenMode === exports.Widget.HiddenMode.Scale &&
                refNode.tabBar.titles.length > 0) {
                if (refNode.tabBar.titles.length == 1) {
                    var existingWidget = refNode.tabBar.titles[0].owner;
                    existingWidget.hiddenMode = exports.Widget.HiddenMode.Scale;
                }
                widget.hiddenMode = exports.Widget.HiddenMode.Scale;
            }
            else {
                widget.hiddenMode = exports.Widget.HiddenMode.Display;
            }
            // Insert the widget's tab relative to the target index.
            refNode.tabBar.insertTab(index + (after ? 1 : 0), widget.title);
            Private$6.addAria(widget, refNode.tabBar);
        };
        /**
         * Insert a widget as a new split area.
         *
         * #### Notes
         * This does not attach the widget to the parent widget.
         */
        DockLayout.prototype._insertSplit = function (widget, ref, refNode, orientation, after) {
            // Do nothing if there is no effective split.
            if (widget === ref && refNode && refNode.tabBar.titles.length === 1) {
                return;
            }
            // Ensure the widget is removed from the current layout.
            this._removeWidget(widget);
            // Create the tab layout node to hold the widget.
            var tabNode = new Private$6.TabLayoutNode(this._createTabBar());
            tabNode.tabBar.addTab(widget.title);
            Private$6.addAria(widget, tabNode.tabBar);
            // Set the root if it does not exist.
            if (!this._root) {
                this._root = tabNode;
                return;
            }
            // If the ref node parent is null, split the root.
            if (!refNode || !refNode.parent) {
                // Ensure the root is split with the correct orientation.
                var root = this._splitRoot(orientation);
                // Determine the insert index for the new tab node.
                var i_2 = after ? root.children.length : 0;
                // Normalize the split node.
                root.normalizeSizes();
                // Create the sizer for new tab node.
                var sizer = Private$6.createSizer(refNode ? 1 : Private$6.GOLDEN_RATIO);
                // Insert the tab node sized to the golden ratio.
                algorithm.ArrayExt.insert(root.children, i_2, tabNode);
                algorithm.ArrayExt.insert(root.sizers, i_2, sizer);
                algorithm.ArrayExt.insert(root.handles, i_2, this._createHandle());
                tabNode.parent = root;
                // Re-normalize the split node to maintain the ratios.
                root.normalizeSizes();
                // Finally, synchronize the visibility of the handles.
                root.syncHandles();
                return;
            }
            // Lookup the split node for the ref widget.
            var splitNode = refNode.parent;
            // If the split node already had the correct orientation,
            // the widget can be inserted into the split node directly.
            if (splitNode.orientation === orientation) {
                // Find the index of the ref node.
                var i_3 = splitNode.children.indexOf(refNode);
                // Normalize the split node.
                splitNode.normalizeSizes();
                // Consume half the space for the insert location.
                var s = (splitNode.sizers[i_3].sizeHint /= 2);
                // Insert the tab node sized to the other half.
                var j_1 = i_3 + (after ? 1 : 0);
                algorithm.ArrayExt.insert(splitNode.children, j_1, tabNode);
                algorithm.ArrayExt.insert(splitNode.sizers, j_1, Private$6.createSizer(s));
                algorithm.ArrayExt.insert(splitNode.handles, j_1, this._createHandle());
                tabNode.parent = splitNode;
                // Finally, synchronize the visibility of the handles.
                splitNode.syncHandles();
                return;
            }
            // Remove the ref node from the split node.
            var i = algorithm.ArrayExt.removeFirstOf(splitNode.children, refNode);
            // Create a new normalized split node for the children.
            var childNode = new Private$6.SplitLayoutNode(orientation);
            childNode.normalized = true;
            // Add the ref node sized to half the space.
            childNode.children.push(refNode);
            childNode.sizers.push(Private$6.createSizer(0.5));
            childNode.handles.push(this._createHandle());
            refNode.parent = childNode;
            // Add the tab node sized to the other half.
            var j = after ? 1 : 0;
            algorithm.ArrayExt.insert(childNode.children, j, tabNode);
            algorithm.ArrayExt.insert(childNode.sizers, j, Private$6.createSizer(0.5));
            algorithm.ArrayExt.insert(childNode.handles, j, this._createHandle());
            tabNode.parent = childNode;
            // Synchronize the visibility of the handles.
            childNode.syncHandles();
            // Finally, add the new child node to the original split node.
            algorithm.ArrayExt.insert(splitNode.children, i, childNode);
            childNode.parent = splitNode;
        };
        /**
         * Ensure the root is a split node with the given orientation.
         */
        DockLayout.prototype._splitRoot = function (orientation) {
            // Bail early if the root already meets the requirements.
            var oldRoot = this._root;
            if (oldRoot instanceof Private$6.SplitLayoutNode) {
                if (oldRoot.orientation === orientation) {
                    return oldRoot;
                }
            }
            // Create a new root node with the specified orientation.
            var newRoot = (this._root = new Private$6.SplitLayoutNode(orientation));
            // Add the old root to the new root.
            if (oldRoot) {
                newRoot.children.push(oldRoot);
                newRoot.sizers.push(Private$6.createSizer(0));
                newRoot.handles.push(this._createHandle());
                oldRoot.parent = newRoot;
            }
            // Return the new root as a convenience.
            return newRoot;
        };
        /**
         * Fit the layout to the total size required by the widgets.
         */
        DockLayout.prototype._fit = function () {
            // Set up the computed minimum size.
            var minW = 0;
            var minH = 0;
            // Update the size limits for the layout tree.
            if (this._root) {
                var limits = this._root.fit(this._spacing, this._items);
                minW = limits.minWidth;
                minH = limits.minHeight;
            }
            // Update the box sizing and add it to the computed min size.
            var box = (this._box = domutils.ElementExt.boxSizing(this.parent.node));
            minW += box.horizontalSum;
            minH += box.verticalSum;
            // Update the parent's min size constraints.
            var style = this.parent.node.style;
            style.minWidth = minW + "px";
            style.minHeight = minH + "px";
            // Set the dirty flag to ensure only a single update occurs.
            this._dirty = true;
            // Notify the ancestor that it should fit immediately. This may
            // cause a resize of the parent, fulfilling the required update.
            if (this.parent.parent) {
                messaging.MessageLoop.sendMessage(this.parent.parent, exports.Widget.Msg.FitRequest);
            }
            // If the dirty flag is still set, the parent was not resized.
            // Trigger the required update on the parent widget immediately.
            if (this._dirty) {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
            }
        };
        /**
         * Update the layout position and size of the widgets.
         *
         * The parent offset dimensions should be `-1` if unknown.
         */
        DockLayout.prototype._update = function (offsetWidth, offsetHeight) {
            // Clear the dirty flag to indicate the update occurred.
            this._dirty = false;
            // Bail early if there is no root layout node.
            if (!this._root) {
                return;
            }
            // Measure the parent if the offset dimensions are unknown.
            if (offsetWidth < 0) {
                offsetWidth = this.parent.node.offsetWidth;
            }
            if (offsetHeight < 0) {
                offsetHeight = this.parent.node.offsetHeight;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Compute the actual layout bounds adjusted for border and padding.
            var x = this._box.paddingTop;
            var y = this._box.paddingLeft;
            var width = offsetWidth - this._box.horizontalSum;
            var height = offsetHeight - this._box.verticalSum;
            // Update the geometry of the layout tree.
            this._root.update(x, y, width, height, this._spacing, this._items);
        };
        /**
         * Create a new tab bar for use by the dock layout.
         *
         * #### Notes
         * The tab bar will be attached to the parent if it exists.
         */
        DockLayout.prototype._createTabBar = function () {
            // Create the tab bar using the renderer.
            var tabBar = this.renderer.createTabBar(this._document);
            // Enforce necessary tab bar behavior.
            tabBar.orientation = 'horizontal';
            // Reparent and attach the tab bar to the parent if possible.
            if (this.parent) {
                tabBar.parent = this.parent;
                this.attachWidget(tabBar);
            }
            // Return the initialized tab bar.
            return tabBar;
        };
        /**
         * Create a new handle for the dock layout.
         *
         * #### Notes
         * The handle will be attached to the parent if it exists.
         */
        DockLayout.prototype._createHandle = function () {
            // Create the handle using the renderer.
            var handle = this.renderer.createHandle();
            // Initialize the handle layout behavior.
            var style = handle.style;
            style.position = 'absolute';
            style.top = '0';
            style.left = '0';
            style.width = '0';
            style.height = '0';
            // Attach the handle to the parent if it exists.
            if (this.parent) {
                this.parent.node.appendChild(handle);
            }
            // Return the initialized handle.
            return handle;
        };
        return DockLayout;
    }(exports.Layout));
    /**
     * The namespace for the module implementation details.
     */
    var Private$6;
    (function (Private) {
        /**
         * A fraction used for sizing root panels; ~= `1 / golden_ratio`.
         */
        Private.GOLDEN_RATIO = 0.618;
        /**
         * Create a box sizer with an initial size hint.
         */
        function createSizer(hint) {
            var sizer = new BoxSizer();
            sizer.sizeHint = hint;
            sizer.size = hint;
            return sizer;
        }
        Private.createSizer = createSizer;
        /**
         * Normalize an area config object and collect the visited widgets.
         */
        function normalizeAreaConfig(config, widgetSet) {
            var result;
            if (config.type === 'tab-area') {
                result = normalizeTabAreaConfig(config, widgetSet);
            }
            else {
                result = normalizeSplitAreaConfig(config, widgetSet);
            }
            return result;
        }
        Private.normalizeAreaConfig = normalizeAreaConfig;
        /**
         * Convert a normalized area config into a layout tree.
         */
        function realizeAreaConfig(config, renderer, document) {
            var node;
            if (config.type === 'tab-area') {
                node = realizeTabAreaConfig(config, renderer, document);
            }
            else {
                node = realizeSplitAreaConfig(config, renderer, document);
            }
            return node;
        }
        Private.realizeAreaConfig = realizeAreaConfig;
        /**
         * A layout node which holds the data for a tabbed area.
         */
        var TabLayoutNode = /** @class */ (function () {
            /**
             * Construct a new tab layout node.
             *
             * @param tabBar - The tab bar to use for the layout node.
             */
            function TabLayoutNode(tabBar) {
                /**
                 * The parent of the layout node.
                 */
                this.parent = null;
                this._top = 0;
                this._left = 0;
                this._width = 0;
                this._height = 0;
                var tabSizer = new BoxSizer();
                var widgetSizer = new BoxSizer();
                tabSizer.stretch = 0;
                widgetSizer.stretch = 1;
                this.tabBar = tabBar;
                this.sizers = [tabSizer, widgetSizer];
            }
            Object.defineProperty(TabLayoutNode.prototype, "top", {
                /**
                 * The most recent value for the `top` edge of the layout box.
                 */
                get: function () {
                    return this._top;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(TabLayoutNode.prototype, "left", {
                /**
                 * The most recent value for the `left` edge of the layout box.
                 */
                get: function () {
                    return this._left;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(TabLayoutNode.prototype, "width", {
                /**
                 * The most recent value for the `width` of the layout box.
                 */
                get: function () {
                    return this._width;
                },
                enumerable: true,
                configurable: true
            });
            Object.defineProperty(TabLayoutNode.prototype, "height", {
                /**
                 * The most recent value for the `height` of the layout box.
                 */
                get: function () {
                    return this._height;
                },
                enumerable: true,
                configurable: true
            });
            /**
             * Create an iterator for all widgets in the layout tree.
             */
            TabLayoutNode.prototype.iterAllWidgets = function () {
                return algorithm.chain(algorithm.once(this.tabBar), this.iterUserWidgets());
            };
            /**
             * Create an iterator for the user widgets in the layout tree.
             */
            TabLayoutNode.prototype.iterUserWidgets = function () {
                return algorithm.map(this.tabBar.titles, function (title) { return title.owner; });
            };
            /**
             * Create an iterator for the selected widgets in the layout tree.
             */
            TabLayoutNode.prototype.iterSelectedWidgets = function () {
                var title = this.tabBar.currentTitle;
                return title ? algorithm.once(title.owner) : algorithm.empty();
            };
            /**
             * Create an iterator for the tab bars in the layout tree.
             */
            TabLayoutNode.prototype.iterTabBars = function () {
                return algorithm.once(this.tabBar);
            };
            /**
             * Create an iterator for the handles in the layout tree.
             */
            TabLayoutNode.prototype.iterHandles = function () {
                return algorithm.empty();
            };
            /**
             * Find the tab layout node which contains the given widget.
             */
            TabLayoutNode.prototype.findTabNode = function (widget) {
                return this.tabBar.titles.indexOf(widget.title) !== -1 ? this : null;
            };
            /**
             * Find the split layout node which contains the given handle.
             */
            TabLayoutNode.prototype.findSplitNode = function (handle) {
                return null;
            };
            /**
             * Find the first tab layout node in a layout tree.
             */
            TabLayoutNode.prototype.findFirstTabNode = function () {
                return this;
            };
            /**
             * Find the tab layout node which contains the local point.
             */
            TabLayoutNode.prototype.hitTestTabNodes = function (x, y) {
                if (x < this._left || x >= this._left + this._width) {
                    return null;
                }
                if (y < this._top || y >= this._top + this._height) {
                    return null;
                }
                return this;
            };
            /**
             * Create a configuration object for the layout tree.
             */
            TabLayoutNode.prototype.createConfig = function () {
                var widgets = this.tabBar.titles.map(function (title) { return title.owner; });
                var currentIndex = this.tabBar.currentIndex;
                return { type: 'tab-area', widgets: widgets, currentIndex: currentIndex };
            };
            /**
             * Recursively hold all of the sizes in the layout tree.
             *
             * This ignores the sizers of tab layout nodes.
             */
            TabLayoutNode.prototype.holdAllSizes = function () {
                return;
            };
            /**
             * Fit the layout tree.
             */
            TabLayoutNode.prototype.fit = function (spacing, items) {
                // Set up the limit variables.
                var minWidth = 0;
                var minHeight = 0;
                var maxWidth = Infinity;
                var maxHeight = Infinity;
                // Lookup the tab bar layout item.
                var tabBarItem = items.get(this.tabBar);
                // Lookup the widget layout item.
                var current = this.tabBar.currentTitle;
                var widgetItem = current ? items.get(current.owner) : undefined;
                // Lookup the tab bar and widget sizers.
                var _a = this.sizers, tabBarSizer = _a[0], widgetSizer = _a[1];
                // Update the tab bar limits.
                if (tabBarItem) {
                    tabBarItem.fit();
                }
                // Update the widget limits.
                if (widgetItem) {
                    widgetItem.fit();
                }
                // Update the results and sizer for the tab bar.
                if (tabBarItem && !tabBarItem.isHidden) {
                    minWidth = Math.max(minWidth, tabBarItem.minWidth);
                    minHeight += tabBarItem.minHeight;
                    tabBarSizer.minSize = tabBarItem.minHeight;
                    tabBarSizer.maxSize = tabBarItem.maxHeight;
                }
                else {
                    tabBarSizer.minSize = 0;
                    tabBarSizer.maxSize = 0;
                }
                // Update the results and sizer for the current widget.
                if (widgetItem && !widgetItem.isHidden) {
                    minWidth = Math.max(minWidth, widgetItem.minWidth);
                    minHeight += widgetItem.minHeight;
                    widgetSizer.minSize = widgetItem.minHeight;
                    widgetSizer.maxSize = Infinity;
                }
                else {
                    widgetSizer.minSize = 0;
                    widgetSizer.maxSize = Infinity;
                }
                // Return the computed size limits for the layout node.
                return { minWidth: minWidth, minHeight: minHeight, maxWidth: maxWidth, maxHeight: maxHeight };
            };
            /**
             * Update the layout tree.
             */
            TabLayoutNode.prototype.update = function (left, top, width, height, spacing, items) {
                // Update the layout box values.
                this._top = top;
                this._left = left;
                this._width = width;
                this._height = height;
                // Lookup the tab bar layout item.
                var tabBarItem = items.get(this.tabBar);
                // Lookup the widget layout item.
                var current = this.tabBar.currentTitle;
                var widgetItem = current ? items.get(current.owner) : undefined;
                // Distribute the layout space to the sizers.
                exports.BoxEngine.calc(this.sizers, height);
                // Update the tab bar item using the computed size.
                if (tabBarItem && !tabBarItem.isHidden) {
                    var size = this.sizers[0].size;
                    tabBarItem.update(left, top, width, size);
                    top += size;
                }
                // Layout the widget using the computed size.
                if (widgetItem && !widgetItem.isHidden) {
                    var size = this.sizers[1].size;
                    widgetItem.update(left, top, width, size);
                }
            };
            return TabLayoutNode;
        }());
        Private.TabLayoutNode = TabLayoutNode;
        /**
         * A layout node which holds the data for a split area.
         */
        var SplitLayoutNode = /** @class */ (function () {
            /**
             * Construct a new split layout node.
             *
             * @param orientation - The orientation of the node.
             */
            function SplitLayoutNode(orientation) {
                /**
                 * The parent of the layout node.
                 */
                this.parent = null;
                /**
                 * Whether the sizers have been normalized.
                 */
                this.normalized = false;
                /**
                 * The child nodes for the split node.
                 */
                this.children = [];
                /**
                 * The box sizers for the layout children.
                 */
                this.sizers = [];
                /**
                 * The handles for the layout children.
                 */
                this.handles = [];
                this.orientation = orientation;
            }
            /**
             * Create an iterator for all widgets in the layout tree.
             */
            SplitLayoutNode.prototype.iterAllWidgets = function () {
                var children = algorithm.map(this.children, function (child) { return child.iterAllWidgets(); });
                return new algorithm.ChainIterator(children);
            };
            /**
             * Create an iterator for the user widgets in the layout tree.
             */
            SplitLayoutNode.prototype.iterUserWidgets = function () {
                var children = algorithm.map(this.children, function (child) { return child.iterUserWidgets(); });
                return new algorithm.ChainIterator(children);
            };
            /**
             * Create an iterator for the selected widgets in the layout tree.
             */
            SplitLayoutNode.prototype.iterSelectedWidgets = function () {
                var children = algorithm.map(this.children, function (child) { return child.iterSelectedWidgets(); });
                return new algorithm.ChainIterator(children);
            };
            /**
             * Create an iterator for the tab bars in the layout tree.
             */
            SplitLayoutNode.prototype.iterTabBars = function () {
                var children = algorithm.map(this.children, function (child) { return child.iterTabBars(); });
                return new algorithm.ChainIterator(children);
            };
            /**
             * Create an iterator for the handles in the layout tree.
             */
            SplitLayoutNode.prototype.iterHandles = function () {
                var children = algorithm.map(this.children, function (child) { return child.iterHandles(); });
                return algorithm.chain(this.handles, new algorithm.ChainIterator(children));
            };
            /**
             * Find the tab layout node which contains the given widget.
             */
            SplitLayoutNode.prototype.findTabNode = function (widget) {
                for (var i = 0, n = this.children.length; i < n; ++i) {
                    var result = this.children[i].findTabNode(widget);
                    if (result) {
                        return result;
                    }
                }
                return null;
            };
            /**
             * Find the split layout node which contains the given handle.
             */
            SplitLayoutNode.prototype.findSplitNode = function (handle) {
                var index = this.handles.indexOf(handle);
                if (index !== -1) {
                    return { index: index, node: this };
                }
                for (var i = 0, n = this.children.length; i < n; ++i) {
                    var result = this.children[i].findSplitNode(handle);
                    if (result) {
                        return result;
                    }
                }
                return null;
            };
            /**
             * Find the first tab layout node in a layout tree.
             */
            SplitLayoutNode.prototype.findFirstTabNode = function () {
                if (this.children.length === 0) {
                    return null;
                }
                return this.children[0].findFirstTabNode();
            };
            /**
             * Find the tab layout node which contains the local point.
             */
            SplitLayoutNode.prototype.hitTestTabNodes = function (x, y) {
                for (var i = 0, n = this.children.length; i < n; ++i) {
                    var result = this.children[i].hitTestTabNodes(x, y);
                    if (result) {
                        return result;
                    }
                }
                return null;
            };
            /**
             * Create a configuration object for the layout tree.
             */
            SplitLayoutNode.prototype.createConfig = function () {
                var orientation = this.orientation;
                var sizes = this.createNormalizedSizes();
                var children = this.children.map(function (child) { return child.createConfig(); });
                return { type: 'split-area', orientation: orientation, children: children, sizes: sizes };
            };
            /**
             * Sync the visibility and orientation of the handles.
             */
            SplitLayoutNode.prototype.syncHandles = function () {
                var _this = this;
                algorithm.each(this.handles, function (handle, i) {
                    handle.setAttribute('data-orientation', _this.orientation);
                    if (i === _this.handles.length - 1) {
                        handle.classList.add('lm-mod-hidden');
                        /* <DEPRECATED> */
                        handle.classList.add('p-mod-hidden');
                        /* </DEPRECATED> */
                    }
                    else {
                        handle.classList.remove('lm-mod-hidden');
                        /* <DEPRECATED> */
                        handle.classList.remove('p-mod-hidden');
                        /* </DEPRECATED> */
                    }
                });
            };
            /**
             * Hold the current sizes of the box sizers.
             *
             * This sets the size hint of each sizer to its current size.
             */
            SplitLayoutNode.prototype.holdSizes = function () {
                algorithm.each(this.sizers, function (sizer) {
                    sizer.sizeHint = sizer.size;
                });
            };
            /**
             * Recursively hold all of the sizes in the layout tree.
             *
             * This ignores the sizers of tab layout nodes.
             */
            SplitLayoutNode.prototype.holdAllSizes = function () {
                algorithm.each(this.children, function (child) { return child.holdAllSizes(); });
                this.holdSizes();
            };
            /**
             * Normalize the sizes of the split layout node.
             */
            SplitLayoutNode.prototype.normalizeSizes = function () {
                // Bail early if the sizers are empty.
                var n = this.sizers.length;
                if (n === 0) {
                    return;
                }
                // Hold the current sizes of the sizers.
                this.holdSizes();
                // Compute the sum of the sizes.
                var sum = algorithm.reduce(this.sizers, function (v, sizer) { return v + sizer.sizeHint; }, 0);
                // Normalize the sizes based on the sum.
                if (sum === 0) {
                    algorithm.each(this.sizers, function (sizer) {
                        sizer.size = sizer.sizeHint = 1 / n;
                    });
                }
                else {
                    algorithm.each(this.sizers, function (sizer) {
                        sizer.size = sizer.sizeHint /= sum;
                    });
                }
                // Mark the sizes as normalized.
                this.normalized = true;
            };
            /**
             * Snap the normalized sizes of the split layout node.
             */
            SplitLayoutNode.prototype.createNormalizedSizes = function () {
                // Bail early if the sizers are empty.
                var n = this.sizers.length;
                if (n === 0) {
                    return [];
                }
                // Grab the current sizes of the sizers.
                var sizes = this.sizers.map(function (sizer) { return sizer.size; });
                // Compute the sum of the sizes.
                var sum = algorithm.reduce(sizes, function (v, size) { return v + size; }, 0);
                // Normalize the sizes based on the sum.
                if (sum === 0) {
                    algorithm.each(sizes, function (size, i) {
                        sizes[i] = 1 / n;
                    });
                }
                else {
                    algorithm.each(sizes, function (size, i) {
                        sizes[i] = size / sum;
                    });
                }
                // Return the normalized sizes.
                return sizes;
            };
            /**
             * Fit the layout tree.
             */
            SplitLayoutNode.prototype.fit = function (spacing, items) {
                // Compute the required fixed space.
                var horizontal = this.orientation === 'horizontal';
                var fixed = Math.max(0, this.children.length - 1) * spacing;
                // Set up the limit variables.
                var minWidth = horizontal ? fixed : 0;
                var minHeight = horizontal ? 0 : fixed;
                var maxWidth = Infinity;
                var maxHeight = Infinity;
                // Fit the children and update the limits.
                for (var i = 0, n = this.children.length; i < n; ++i) {
                    var limits = this.children[i].fit(spacing, items);
                    if (horizontal) {
                        minHeight = Math.max(minHeight, limits.minHeight);
                        minWidth += limits.minWidth;
                        this.sizers[i].minSize = limits.minWidth;
                    }
                    else {
                        minWidth = Math.max(minWidth, limits.minWidth);
                        minHeight += limits.minHeight;
                        this.sizers[i].minSize = limits.minHeight;
                    }
                }
                // Return the computed limits for the layout node.
                return { minWidth: minWidth, minHeight: minHeight, maxWidth: maxWidth, maxHeight: maxHeight };
            };
            /**
             * Update the layout tree.
             */
            SplitLayoutNode.prototype.update = function (left, top, width, height, spacing, items) {
                // Compute the available layout space.
                var horizontal = this.orientation === 'horizontal';
                var fixed = Math.max(0, this.children.length - 1) * spacing;
                var space = Math.max(0, (horizontal ? width : height) - fixed);
                // De-normalize the sizes if needed.
                if (this.normalized) {
                    algorithm.each(this.sizers, function (sizer) {
                        sizer.sizeHint *= space;
                    });
                    this.normalized = false;
                }
                // Distribute the layout space to the sizers.
                exports.BoxEngine.calc(this.sizers, space);
                // Update the geometry of the child nodes and handles.
                for (var i = 0, n = this.children.length; i < n; ++i) {
                    var child = this.children[i];
                    var size = this.sizers[i].size;
                    var handleStyle = this.handles[i].style;
                    if (horizontal) {
                        child.update(left, top, size, height, spacing, items);
                        left += size;
                        handleStyle.top = top + "px";
                        handleStyle.left = left + "px";
                        handleStyle.width = spacing + "px";
                        handleStyle.height = height + "px";
                        left += spacing;
                    }
                    else {
                        child.update(left, top, width, size, spacing, items);
                        top += size;
                        handleStyle.top = top + "px";
                        handleStyle.left = left + "px";
                        handleStyle.width = width + "px";
                        handleStyle.height = spacing + "px";
                        top += spacing;
                    }
                }
            };
            return SplitLayoutNode;
        }());
        Private.SplitLayoutNode = SplitLayoutNode;
        function addAria(widget, tabBar) {
            widget.node.setAttribute('role', 'tabpanel');
            var renderer = tabBar.renderer;
            if (renderer instanceof exports.TabBar.Renderer) {
                var tabId = renderer.createTabKey({
                    title: widget.title,
                    current: false,
                    zIndex: 0
                });
                widget.node.setAttribute('aria-labelledby', tabId);
            }
        }
        Private.addAria = addAria;
        function removeAria(widget) {
            widget.node.removeAttribute('role');
            widget.node.removeAttribute('aria-labelledby');
        }
        Private.removeAria = removeAria;
        /**
         * Normalize a tab area config and collect the visited widgets.
         */
        function normalizeTabAreaConfig(config, widgetSet) {
            // Bail early if there is no content.
            if (config.widgets.length === 0) {
                return null;
            }
            // Setup the filtered widgets array.
            var widgets = [];
            // Filter the config for unique widgets.
            algorithm.each(config.widgets, function (widget) {
                if (!widgetSet.has(widget)) {
                    widgetSet.add(widget);
                    widgets.push(widget);
                }
            });
            // Bail if there are no effective widgets.
            if (widgets.length === 0) {
                return null;
            }
            // Normalize the current index.
            var index = config.currentIndex;
            if (index !== -1 && (index < 0 || index >= widgets.length)) {
                index = 0;
            }
            // Return a normalized config object.
            return { type: 'tab-area', widgets: widgets, currentIndex: index };
        }
        /**
         * Normalize a split area config and collect the visited widgets.
         */
        function normalizeSplitAreaConfig(config, widgetSet) {
            // Set up the result variables.
            var orientation = config.orientation;
            var children = [];
            var sizes = [];
            // Normalize the config children.
            for (var i = 0, n = config.children.length; i < n; ++i) {
                // Normalize the child config.
                var child = normalizeAreaConfig(config.children[i], widgetSet);
                // Ignore an empty child.
                if (!child) {
                    continue;
                }
                // Add the child or hoist its content as appropriate.
                if (child.type === 'tab-area' || child.orientation !== orientation) {
                    children.push(child);
                    sizes.push(Math.abs(config.sizes[i] || 0));
                }
                else {
                    children.push.apply(children, child.children);
                    sizes.push.apply(sizes, child.sizes);
                }
            }
            // Bail if there are no effective children.
            if (children.length === 0) {
                return null;
            }
            // If there is only one effective child, return that child.
            if (children.length === 1) {
                return children[0];
            }
            // Return a normalized config object.
            return { type: 'split-area', orientation: orientation, children: children, sizes: sizes };
        }
        /**
         * Convert a normalized tab area config into a layout tree.
         */
        function realizeTabAreaConfig(config, renderer, document) {
            // Create the tab bar for the layout node.
            var tabBar = renderer.createTabBar(document);
            // Hide each widget and add it to the tab bar.
            algorithm.each(config.widgets, function (widget) {
                widget.hide();
                tabBar.addTab(widget.title);
                Private.addAria(widget, tabBar);
            });
            // Set the current index of the tab bar.
            tabBar.currentIndex = config.currentIndex;
            // Return the new tab layout node.
            return new TabLayoutNode(tabBar);
        }
        /**
         * Convert a normalized split area config into a layout tree.
         */
        function realizeSplitAreaConfig(config, renderer, document) {
            // Create the split layout node.
            var node = new SplitLayoutNode(config.orientation);
            // Add each child to the layout node.
            algorithm.each(config.children, function (child, i) {
                // Create the child data for the layout node.
                var childNode = realizeAreaConfig(child, renderer, document);
                var sizer = createSizer(config.sizes[i]);
                var handle = renderer.createHandle();
                // Add the child data to the layout node.
                node.children.push(childNode);
                node.handles.push(handle);
                node.sizers.push(sizer);
                // Update the parent for the child node.
                childNode.parent = node;
            });
            // Synchronize the handle state for the layout node.
            node.syncHandles();
            // Normalize the sizes for the layout node.
            node.normalizeSizes();
            // Return the new layout node.
            return node;
        }
    })(Private$6 || (Private$6 = {}));

    /**
     * A widget which provides a flexible docking area for widgets.
     */
    exports.DockPanel = /** @class */ (function (_super) {
        __extends(DockPanel, _super);
        /**
         * Construct a new dock panel.
         *
         * @param options - The options for initializing the panel.
         */
        function DockPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this) || this;
            _this._drag = null;
            _this._tabsMovable = true;
            _this._tabsConstrained = false;
            _this._addButtonEnabled = false;
            _this._pressData = null;
            _this._layoutModified = new signaling.Signal(_this);
            _this._addRequested = new signaling.Signal(_this);
            _this.addClass('lm-DockPanel');
            /* <DEPRECATED> */
            _this.addClass('p-DockPanel');
            /* </DEPRECATED> */
            _this._document = options.document || document;
            _this._mode = options.mode || 'multiple-document';
            _this._renderer = options.renderer || DockPanel.defaultRenderer;
            _this._edges = options.edges || Private$5.DEFAULT_EDGES;
            if (options.tabsMovable !== undefined) {
                _this._tabsMovable = options.tabsMovable;
            }
            if (options.tabsConstrained !== undefined) {
                _this._tabsConstrained = options.tabsConstrained;
            }
            if (options.addButtonEnabled !== undefined) {
                _this._addButtonEnabled = options.addButtonEnabled;
            }
            // Toggle the CSS mode attribute.
            _this.dataset['mode'] = _this._mode;
            // Create the delegate renderer for the layout.
            var renderer = {
                createTabBar: function () { return _this._createTabBar(); },
                createHandle: function () { return _this._createHandle(); }
            };
            // Set up the dock layout for the panel.
            _this.layout = new DockLayout({
                document: _this._document,
                renderer: renderer,
                spacing: options.spacing,
                hiddenMode: options.hiddenMode
            });
            // Set up the overlay drop indicator.
            _this.overlay = options.overlay || new DockPanel.Overlay();
            _this.node.appendChild(_this.overlay.node);
            return _this;
        }
        /**
         * Dispose of the resources held by the panel.
         */
        DockPanel.prototype.dispose = function () {
            // Ensure the mouse is released.
            this._releaseMouse();
            // Hide the overlay.
            this.overlay.hide(0);
            // Cancel a drag if one is in progress.
            if (this._drag) {
                this._drag.dispose();
            }
            // Dispose of the base class.
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(DockPanel.prototype, "hiddenMode", {
            /**
             * The method for hiding widgets.
             */
            get: function () {
                return this.layout.hiddenMode;
            },
            /**
             * Set the method for hiding widgets.
             */
            set: function (v) {
                this.layout.hiddenMode = v;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "layoutModified", {
            /**
             * A signal emitted when the layout configuration is modified.
             *
             * #### Notes
             * This signal is emitted whenever the current layout configuration
             * may have changed.
             *
             * This signal is emitted asynchronously in a collapsed fashion, so
             * that multiple synchronous modifications results in only a single
             * emit of the signal.
             */
            get: function () {
                return this._layoutModified;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "addRequested", {
            /**
             * A signal emitted when the add button on a tab bar is clicked.
             *
             */
            get: function () {
                return this._addRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "renderer", {
            /**
             * The renderer used by the dock panel.
             */
            get: function () {
                return this.layout.renderer;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "spacing", {
            /**
             * Get the spacing between the widgets.
             */
            get: function () {
                return this.layout.spacing;
            },
            /**
             * Set the spacing between the widgets.
             */
            set: function (value) {
                this.layout.spacing = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "mode", {
            /**
             * Get the mode for the dock panel.
             */
            get: function () {
                return this._mode;
            },
            /**
             * Set the mode for the dock panel.
             *
             * #### Notes
             * Changing the mode is a destructive operation with respect to the
             * panel's layout configuration. If layout state must be preserved,
             * save the current layout config before changing the mode.
             */
            set: function (value) {
                // Bail early if the mode does not change.
                if (this._mode === value) {
                    return;
                }
                // Update the internal mode.
                this._mode = value;
                // Toggle the CSS mode attribute.
                this.dataset['mode'] = value;
                // Get the layout for the panel.
                var layout = this.layout;
                // Configure the layout for the specified mode.
                switch (value) {
                    case 'multiple-document':
                        algorithm.each(layout.tabBars(), function (tabBar) {
                            tabBar.show();
                        });
                        break;
                    case 'single-document':
                        layout.restoreLayout(Private$5.createSingleDocumentConfig(this));
                        break;
                    default:
                        throw 'unreachable';
                }
                // Schedule an emit of the layout modified signal.
                messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "tabsMovable", {
            /**
             * Whether the tabs can be dragged / moved at runtime.
             */
            get: function () {
                return this._tabsMovable;
            },
            /**
             * Enable / Disable draggable / movable tabs.
             */
            set: function (value) {
                this._tabsMovable = value;
                algorithm.each(this.tabBars(), function (tabbar) {
                    tabbar.tabsMovable = value;
                });
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "tabsConstrained", {
            /**
             * Whether the tabs are constrained to their source dock panel
             */
            get: function () {
                return this._tabsConstrained;
            },
            /**
             * Constrain/Allow tabs to be dragged outside of this dock panel
             */
            set: function (value) {
                this._tabsConstrained = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "addButtonEnabled", {
            /**
             * Whether the add buttons for each tab bar are enabled.
             */
            get: function () {
                return this._addButtonEnabled;
            },
            /**
             * Set whether the add buttons for each tab bar are enabled.
             */
            set: function (value) {
                this._addButtonEnabled = value;
                algorithm.each(this.tabBars(), function (tabbar) {
                    tabbar.addButtonEnabled = value;
                });
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(DockPanel.prototype, "isEmpty", {
            /**
             * Whether the dock panel is empty.
             */
            get: function () {
                return this.layout.isEmpty;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Create an iterator over the user widgets in the panel.
         *
         * @returns A new iterator over the user widgets in the panel.
         *
         * #### Notes
         * This iterator does not include the generated tab bars.
         */
        DockPanel.prototype.widgets = function () {
            return this.layout.widgets();
        };
        /**
         * Create an iterator over the selected widgets in the panel.
         *
         * @returns A new iterator over the selected user widgets.
         *
         * #### Notes
         * This iterator yields the widgets corresponding to the current tab
         * of each tab bar in the panel.
         */
        DockPanel.prototype.selectedWidgets = function () {
            return this.layout.selectedWidgets();
        };
        /**
         * Create an iterator over the tab bars in the panel.
         *
         * @returns A new iterator over the tab bars in the panel.
         *
         * #### Notes
         * This iterator does not include the user widgets.
         */
        DockPanel.prototype.tabBars = function () {
            return this.layout.tabBars();
        };
        /**
         * Create an iterator over the handles in the panel.
         *
         * @returns A new iterator over the handles in the panel.
         */
        DockPanel.prototype.handles = function () {
            return this.layout.handles();
        };
        /**
         * Select a specific widget in the dock panel.
         *
         * @param widget - The widget of interest.
         *
         * #### Notes
         * This will make the widget the current widget in its tab area.
         */
        DockPanel.prototype.selectWidget = function (widget) {
            // Find the tab bar which contains the widget.
            var tabBar = algorithm.find(this.tabBars(), function (bar) {
                return bar.titles.indexOf(widget.title) !== -1;
            });
            // Throw an error if no tab bar is found.
            if (!tabBar) {
                throw new Error('Widget is not contained in the dock panel.');
            }
            // Ensure the widget is the current widget.
            tabBar.currentTitle = widget.title;
        };
        /**
         * Activate a specified widget in the dock panel.
         *
         * @param widget - The widget of interest.
         *
         * #### Notes
         * This will select and activate the given widget.
         */
        DockPanel.prototype.activateWidget = function (widget) {
            this.selectWidget(widget);
            widget.activate();
        };
        /**
         * Save the current layout configuration of the dock panel.
         *
         * @returns A new config object for the current layout state.
         *
         * #### Notes
         * The return value can be provided to the `restoreLayout` method
         * in order to restore the layout to its current configuration.
         */
        DockPanel.prototype.saveLayout = function () {
            return this.layout.saveLayout();
        };
        /**
         * Restore the layout to a previously saved configuration.
         *
         * @param config - The layout configuration to restore.
         *
         * #### Notes
         * Widgets which currently belong to the layout but which are not
         * contained in the config will be unparented.
         *
         * The dock panel automatically reverts to `'multiple-document'`
         * mode when a layout config is restored.
         */
        DockPanel.prototype.restoreLayout = function (config) {
            // Reset the mode.
            this._mode = 'multiple-document';
            // Restore the layout.
            this.layout.restoreLayout(config);
            // Flush the message loop on IE and Edge to prevent flicker.
            if (domutils.Platform.IS_EDGE || domutils.Platform.IS_IE) {
                messaging.MessageLoop.flush();
            }
            // Schedule an emit of the layout modified signal.
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Add a widget to the dock panel.
         *
         * @param widget - The widget to add to the dock panel.
         *
         * @param options - The additional options for adding the widget.
         *
         * #### Notes
         * If the panel is in single document mode, the options are ignored
         * and the widget is always added as tab in the hidden tab bar.
         */
        DockPanel.prototype.addWidget = function (widget, options) {
            if (options === void 0) { options = {}; }
            // Add the widget to the layout.
            if (this._mode === 'single-document') {
                this.layout.addWidget(widget);
            }
            else {
                this.layout.addWidget(widget, options);
            }
            // Schedule an emit of the layout modified signal.
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Process a message sent to the widget.
         *
         * @param msg - The message sent to the widget.
         */
        DockPanel.prototype.processMessage = function (msg) {
            if (msg.type === 'layout-modified') {
                this._layoutModified.emit(undefined);
            }
            else {
                _super.prototype.processMessage.call(this, msg);
            }
        };
        /**
         * Handle the DOM events for the dock panel.
         *
         * @param event - The DOM event sent to the panel.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the panel's DOM node. It should
         * not be called directly by user code.
         */
        DockPanel.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'lm-dragenter':
                    this._evtDragEnter(event);
                    break;
                case 'lm-dragleave':
                    this._evtDragLeave(event);
                    break;
                case 'lm-dragover':
                    this._evtDragOver(event);
                    break;
                case 'lm-drop':
                    this._evtDrop(event);
                    break;
                case 'mousedown': // <DEPRECATED>
                    this._evtMouseDown(event);
                    break;
                case 'mousemove': // <DEPRECATED>
                    this._evtMouseMove(event);
                    break;
                case 'mouseup': // <DEPRECATED>
                    this._evtMouseUp(event);
                    break;
                case 'pointerdown':
                    this._evtMouseDown(event);
                    break;
                case 'pointermove':
                    this._evtMouseMove(event);
                    break;
                case 'pointerup':
                    this._evtMouseUp(event);
                    break;
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        DockPanel.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('lm-dragenter', this);
            this.node.addEventListener('lm-dragleave', this);
            this.node.addEventListener('lm-dragover', this);
            this.node.addEventListener('lm-drop', this);
            this.node.addEventListener('mousedown', this); // <DEPRECATED>
            this.node.addEventListener('pointerdown', this);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        DockPanel.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('lm-dragenter', this);
            this.node.removeEventListener('lm-dragleave', this);
            this.node.removeEventListener('lm-dragover', this);
            this.node.removeEventListener('lm-drop', this);
            this.node.removeEventListener('mousedown', this); // <DEPRECATED>
            this.node.removeEventListener('pointerdown', this);
            this._releaseMouse();
        };
        /**
         * A message handler invoked on a `'child-added'` message.
         */
        DockPanel.prototype.onChildAdded = function (msg) {
            // Ignore the generated tab bars.
            if (Private$5.isGeneratedTabBarProperty.get(msg.child)) {
                return;
            }
            // Add the widget class to the child.
            msg.child.addClass('lm-DockPanel-widget');
            /* <DEPRECATED> */
            msg.child.addClass('p-DockPanel-widget');
            /* </DEPRECATED> */
        };
        /**
         * A message handler invoked on a `'child-removed'` message.
         */
        DockPanel.prototype.onChildRemoved = function (msg) {
            // Ignore the generated tab bars.
            if (Private$5.isGeneratedTabBarProperty.get(msg.child)) {
                return;
            }
            // Remove the widget class from the child.
            msg.child.removeClass('lm-DockPanel-widget');
            /* <DEPRECATED> */
            msg.child.removeClass('p-DockPanel-widget');
            /* </DEPRECATED> */
            // Schedule an emit of the layout modified signal.
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Handle the `'lm-dragenter'` event for the dock panel.
         */
        DockPanel.prototype._evtDragEnter = function (event) {
            // If the factory mime type is present, mark the event as
            // handled in order to get the rest of the drag events.
            if (event.mimeData.hasData('application/vnd.lumino.widget-factory')) {
                event.preventDefault();
                event.stopPropagation();
            }
        };
        /**
         * Handle the `'lm-dragleave'` event for the dock panel.
         */
        DockPanel.prototype._evtDragLeave = function (event) {
            // Mark the event as handled.
            event.preventDefault();
            event.stopPropagation();
            // The new target might be a descendant, so we might still handle the drop.
            // Hide asynchronously so that if a lm-dragover event bubbles up to us, the
            // hide is cancelled by the lm-dragover handler's show overlay logic.
            this.overlay.hide(1);
        };
        /**
         * Handle the `'lm-dragover'` event for the dock panel.
         */
        DockPanel.prototype._evtDragOver = function (event) {
            // Mark the event as handled.
            event.preventDefault();
            event.stopPropagation();
            // Show the drop indicator overlay and update the drop
            // action based on the drop target zone under the mouse.
            if ((this._tabsConstrained && event.source !== this) ||
                this._showOverlay(event.clientX, event.clientY) === 'invalid') {
                event.dropAction = 'none';
            }
            else {
                event.dropAction = event.proposedAction;
            }
        };
        /**
         * Handle the `'lm-drop'` event for the dock panel.
         */
        DockPanel.prototype._evtDrop = function (event) {
            // Mark the event as handled.
            event.preventDefault();
            event.stopPropagation();
            // Hide the drop indicator overlay.
            this.overlay.hide(0);
            // Bail if the proposed action is to do nothing.
            if (event.proposedAction === 'none') {
                event.dropAction = 'none';
                return;
            }
            // Find the drop target under the mouse.
            var clientX = event.clientX, clientY = event.clientY;
            var _a = Private$5.findDropTarget(this, clientX, clientY, this._edges), zone = _a.zone, target = _a.target;
            // Bail if the drop zone is invalid.
            if (zone === 'invalid') {
                event.dropAction = 'none';
                return;
            }
            // Bail if the factory mime type has invalid data.
            var mimeData = event.mimeData;
            var factory = mimeData.getData('application/vnd.lumino.widget-factory');
            if (typeof factory !== 'function') {
                event.dropAction = 'none';
                return;
            }
            // Bail if the factory does not produce a widget.
            var widget = factory();
            if (!(widget instanceof exports.Widget)) {
                event.dropAction = 'none';
                return;
            }
            // Bail if the widget is an ancestor of the dock panel.
            if (widget.contains(this)) {
                event.dropAction = 'none';
                return;
            }
            // Find the reference widget for the drop target.
            var ref = target ? Private$5.getDropRef(target.tabBar) : null;
            // Add the widget according to the indicated drop zone.
            switch (zone) {
                case 'root-all':
                    this.addWidget(widget);
                    break;
                case 'root-top':
                    this.addWidget(widget, { mode: 'split-top' });
                    break;
                case 'root-left':
                    this.addWidget(widget, { mode: 'split-left' });
                    break;
                case 'root-right':
                    this.addWidget(widget, { mode: 'split-right' });
                    break;
                case 'root-bottom':
                    this.addWidget(widget, { mode: 'split-bottom' });
                    break;
                case 'widget-all':
                    this.addWidget(widget, { mode: 'tab-after', ref: ref });
                    break;
                case 'widget-top':
                    this.addWidget(widget, { mode: 'split-top', ref: ref });
                    break;
                case 'widget-left':
                    this.addWidget(widget, { mode: 'split-left', ref: ref });
                    break;
                case 'widget-right':
                    this.addWidget(widget, { mode: 'split-right', ref: ref });
                    break;
                case 'widget-bottom':
                    this.addWidget(widget, { mode: 'split-bottom', ref: ref });
                    break;
                case 'widget-tab':
                    this.addWidget(widget, { mode: 'tab-after', ref: ref });
                    break;
                default:
                    throw 'unreachable';
            }
            // Accept the proposed drop action.
            event.dropAction = event.proposedAction;
            // Activate the dropped widget.
            this.activateWidget(widget);
        };
        /**
         * Handle the `'keydown'` event for the dock panel.
         */
        DockPanel.prototype._evtKeyDown = function (event) {
            // Stop input events during drag.
            event.preventDefault();
            event.stopPropagation();
            // Release the mouse if `Escape` is pressed.
            if (event.keyCode === 27) {
                // Finalize the mouse release.
                this._releaseMouse();
                // Schedule an emit of the layout modified signal.
                messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
            }
        };
        /**
         * Handle the `'mousedown'` event for the dock panel.
         */
        DockPanel.prototype._evtMouseDown = function (event) {
            // Do nothing if the left mouse button is not pressed.
            if (event.button !== 0) {
                return;
            }
            // Find the handle which contains the mouse target, if any.
            var layout = this.layout;
            var target = event.target;
            var handle = algorithm.find(layout.handles(), function (handle) { return handle.contains(target); });
            if (!handle) {
                return;
            }
            // Stop the event when a handle is pressed.
            event.preventDefault();
            event.stopPropagation();
            // Add the extra document listeners.
            this._document.addEventListener('keydown', this, true);
            this._document.addEventListener('mouseup', this, true); // <DEPRECATED>
            this._document.addEventListener('mousemove', this, true); // <DEPRECATED>
            this._document.addEventListener('pointerup', this, true);
            this._document.addEventListener('pointermove', this, true);
            this._document.addEventListener('contextmenu', this, true);
            // Compute the offset deltas for the handle press.
            var rect = handle.getBoundingClientRect();
            var deltaX = event.clientX - rect.left;
            var deltaY = event.clientY - rect.top;
            // Override the cursor and store the press data.
            var style = window.getComputedStyle(handle);
            var override = dragdrop.Drag.overrideCursor(style.cursor, this._document);
            this._pressData = { handle: handle, deltaX: deltaX, deltaY: deltaY, override: override };
        };
        /**
         * Handle the `'mousemove'` event for the dock panel.
         */
        DockPanel.prototype._evtMouseMove = function (event) {
            // Bail early if no drag is in progress.
            if (!this._pressData) {
                return;
            }
            // Stop the event when dragging a handle.
            event.preventDefault();
            event.stopPropagation();
            // Compute the desired offset position for the handle.
            var rect = this.node.getBoundingClientRect();
            var xPos = event.clientX - rect.left - this._pressData.deltaX;
            var yPos = event.clientY - rect.top - this._pressData.deltaY;
            // Set the handle as close to the desired position as possible.
            var layout = this.layout;
            layout.moveHandle(this._pressData.handle, xPos, yPos);
        };
        /**
         * Handle the `'mouseup'` event for the dock panel.
         */
        DockPanel.prototype._evtMouseUp = function (event) {
            // Do nothing if the left mouse button is not released.
            if (event.button !== 0) {
                return;
            }
            // Stop the event when releasing a handle.
            event.preventDefault();
            event.stopPropagation();
            // Finalize the mouse release.
            this._releaseMouse();
            // Schedule an emit of the layout modified signal.
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Release the mouse grab for the dock panel.
         */
        DockPanel.prototype._releaseMouse = function () {
            // Bail early if no drag is in progress.
            if (!this._pressData) {
                return;
            }
            // Clear the override cursor.
            this._pressData.override.dispose();
            this._pressData = null;
            // Remove the extra document listeners.
            this._document.removeEventListener('keydown', this, true);
            this._document.removeEventListener('mouseup', this, true); // <DEPRECATED>
            this._document.removeEventListener('mousemove', this, true); // <DEPRECATED>
            this._document.removeEventListener('pointerup', this, true);
            this._document.removeEventListener('pointermove', this, true);
            this._document.removeEventListener('contextmenu', this, true);
        };
        /**
         * Show the overlay indicator at the given client position.
         *
         * Returns the drop zone at the specified client position.
         *
         * #### Notes
         * If the position is not over a valid zone, the overlay is hidden.
         */
        DockPanel.prototype._showOverlay = function (clientX, clientY) {
            // Find the dock target for the given client position.
            var _a = Private$5.findDropTarget(this, clientX, clientY, this._edges), zone = _a.zone, target = _a.target;
            // If the drop zone is invalid, hide the overlay and bail.
            if (zone === 'invalid') {
                this.overlay.hide(100);
                return zone;
            }
            // Setup the variables needed to compute the overlay geometry.
            var top;
            var left;
            var right;
            var bottom;
            var box = domutils.ElementExt.boxSizing(this.node); // TODO cache this?
            var rect = this.node.getBoundingClientRect();
            // Compute the overlay geometry based on the dock zone.
            switch (zone) {
                case 'root-all':
                    top = box.paddingTop;
                    left = box.paddingLeft;
                    right = box.paddingRight;
                    bottom = box.paddingBottom;
                    break;
                case 'root-top':
                    top = box.paddingTop;
                    left = box.paddingLeft;
                    right = box.paddingRight;
                    bottom = rect.height * Private$5.GOLDEN_RATIO;
                    break;
                case 'root-left':
                    top = box.paddingTop;
                    left = box.paddingLeft;
                    right = rect.width * Private$5.GOLDEN_RATIO;
                    bottom = box.paddingBottom;
                    break;
                case 'root-right':
                    top = box.paddingTop;
                    left = rect.width * Private$5.GOLDEN_RATIO;
                    right = box.paddingRight;
                    bottom = box.paddingBottom;
                    break;
                case 'root-bottom':
                    top = rect.height * Private$5.GOLDEN_RATIO;
                    left = box.paddingLeft;
                    right = box.paddingRight;
                    bottom = box.paddingBottom;
                    break;
                case 'widget-all':
                    top = target.top;
                    left = target.left;
                    right = target.right;
                    bottom = target.bottom;
                    break;
                case 'widget-top':
                    top = target.top;
                    left = target.left;
                    right = target.right;
                    bottom = target.bottom + target.height / 2;
                    break;
                case 'widget-left':
                    top = target.top;
                    left = target.left;
                    right = target.right + target.width / 2;
                    bottom = target.bottom;
                    break;
                case 'widget-right':
                    top = target.top;
                    left = target.left + target.width / 2;
                    right = target.right;
                    bottom = target.bottom;
                    break;
                case 'widget-bottom':
                    top = target.top + target.height / 2;
                    left = target.left;
                    right = target.right;
                    bottom = target.bottom;
                    break;
                case 'widget-tab':
                    var tabHeight = target.tabBar.node.getBoundingClientRect().height;
                    top = target.top;
                    left = target.left;
                    right = target.right;
                    bottom = target.bottom + target.height - tabHeight;
                    break;
                default:
                    throw 'unreachable';
            }
            // Show the overlay with the computed geometry.
            this.overlay.show({ top: top, left: left, right: right, bottom: bottom });
            // Finally, return the computed drop zone.
            return zone;
        };
        /**
         * Create a new tab bar for use by the panel.
         */
        DockPanel.prototype._createTabBar = function () {
            // Create the tab bar.
            var tabBar = this._renderer.createTabBar(this._document);
            // Set the generated tab bar property for the tab bar.
            Private$5.isGeneratedTabBarProperty.set(tabBar, true);
            // Hide the tab bar when in single document mode.
            if (this._mode === 'single-document') {
                tabBar.hide();
            }
            // Enforce necessary tab bar behavior.
            // TODO do we really want to enforce *all* of these?
            tabBar.tabsMovable = this._tabsMovable;
            tabBar.allowDeselect = false;
            tabBar.addButtonEnabled = this._addButtonEnabled;
            tabBar.removeBehavior = 'select-previous-tab';
            tabBar.insertBehavior = 'select-tab-if-needed';
            // Connect the signal handlers for the tab bar.
            tabBar.tabMoved.connect(this._onTabMoved, this);
            tabBar.currentChanged.connect(this._onCurrentChanged, this);
            tabBar.tabCloseRequested.connect(this._onTabCloseRequested, this);
            tabBar.tabDetachRequested.connect(this._onTabDetachRequested, this);
            tabBar.tabActivateRequested.connect(this._onTabActivateRequested, this);
            tabBar.addRequested.connect(this._onTabAddRequested, this);
            // Return the initialized tab bar.
            return tabBar;
        };
        /**
         * Create a new handle for use by the panel.
         */
        DockPanel.prototype._createHandle = function () {
            return this._renderer.createHandle();
        };
        /**
         * Handle the `tabMoved` signal from a tab bar.
         */
        DockPanel.prototype._onTabMoved = function () {
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Handle the `currentChanged` signal from a tab bar.
         */
        DockPanel.prototype._onCurrentChanged = function (sender, args) {
            // Extract the previous and current title from the args.
            var previousTitle = args.previousTitle, currentTitle = args.currentTitle;
            // Hide the previous widget.
            if (previousTitle) {
                previousTitle.owner.hide();
            }
            // Show the current widget.
            if (currentTitle) {
                currentTitle.owner.show();
            }
            // Flush the message loop on IE and Edge to prevent flicker.
            if (domutils.Platform.IS_EDGE || domutils.Platform.IS_IE) {
                messaging.MessageLoop.flush();
            }
            // Schedule an emit of the layout modified signal.
            messaging.MessageLoop.postMessage(this, Private$5.LayoutModified);
        };
        /**
         * Handle the `addRequested` signal from a tab bar.
         */
        DockPanel.prototype._onTabAddRequested = function (sender) {
            this._addRequested.emit(sender);
        };
        /**
         * Handle the `tabActivateRequested` signal from a tab bar.
         */
        DockPanel.prototype._onTabActivateRequested = function (sender, args) {
            args.title.owner.activate();
        };
        /**
         * Handle the `tabCloseRequested` signal from a tab bar.
         */
        DockPanel.prototype._onTabCloseRequested = function (sender, args) {
            args.title.owner.close();
        };
        /**
         * Handle the `tabDetachRequested` signal from a tab bar.
         */
        DockPanel.prototype._onTabDetachRequested = function (sender, args) {
            var _this = this;
            // Do nothing if a drag is already in progress.
            if (this._drag) {
                return;
            }
            // Release the tab bar's hold on the mouse.
            sender.releaseMouse();
            // Extract the data from the args.
            var title = args.title, tab = args.tab, clientX = args.clientX, clientY = args.clientY;
            // Setup the mime data for the drag operation.
            var mimeData = new coreutils.MimeData();
            var factory = function () { return title.owner; };
            mimeData.setData('application/vnd.lumino.widget-factory', factory);
            // Create the drag image for the drag operation.
            var dragImage = tab.cloneNode(true);
            // Create the drag object to manage the drag-drop operation.
            this._drag = new dragdrop.Drag({
                document: this._document,
                mimeData: mimeData,
                dragImage: dragImage,
                proposedAction: 'move',
                supportedActions: 'move',
                source: this
            });
            // Hide the tab node in the original tab.
            tab.classList.add('lm-mod-hidden');
            /* <DEPRECATED> */
            tab.classList.add('p-mod-hidden'); // Create the cleanup callback.
            /* </DEPRECATED> */ var cleanup = function () {
                _this._drag = null;
                tab.classList.remove('lm-mod-hidden');
                /* <DEPRECATED> */
                tab.classList.remove('p-mod-hidden');
                /* </DEPRECATED> */
            };
            // Start the drag operation and cleanup when done.
            this._drag.start(clientX, clientY).then(cleanup);
        };
        return DockPanel;
    }(exports.Widget));
    /**
     * The namespace for the `DockPanel` class statics.
     */
    (function (DockPanel) {
        /**
         * A concrete implementation of `IOverlay`.
         *
         * This is the default overlay implementation for a dock panel.
         */
        var Overlay = /** @class */ (function () {
            /**
             * Construct a new overlay.
             */
            function Overlay() {
                this._timer = -1;
                this._hidden = true;
                this.node = document.createElement('div');
                this.node.classList.add('lm-DockPanel-overlay');
                this.node.classList.add('lm-mod-hidden');
                /* <DEPRECATED> */
                this.node.classList.add('p-DockPanel-overlay');
                this.node.classList.add('p-mod-hidden');
                /* </DEPRECATED> */ this.node.style.position = 'absolute';
            }
            /**
             * Show the overlay using the given overlay geometry.
             *
             * @param geo - The desired geometry for the overlay.
             */
            Overlay.prototype.show = function (geo) {
                // Update the position of the overlay.
                var style = this.node.style;
                style.top = geo.top + "px";
                style.left = geo.left + "px";
                style.right = geo.right + "px";
                style.bottom = geo.bottom + "px";
                // Clear any pending hide timer.
                clearTimeout(this._timer);
                this._timer = -1;
                // If the overlay is already visible, we're done.
                if (!this._hidden) {
                    return;
                }
                // Clear the hidden flag.
                this._hidden = false;
                // Finally, show the overlay.
                this.node.classList.remove('lm-mod-hidden');
                /* <DEPRECATED> */
                this.node.classList.remove('p-mod-hidden');
                /* </DEPRECATED> */
            };
            /**
             * Hide the overlay node.
             *
             * @param delay - The delay (in ms) before hiding the overlay.
             *   A delay value <= 0 will hide the overlay immediately.
             */
            Overlay.prototype.hide = function (delay) {
                var _this = this;
                // Do nothing if the overlay is already hidden.
                if (this._hidden) {
                    return;
                }
                // Hide immediately if the delay is <= 0.
                if (delay <= 0) {
                    clearTimeout(this._timer);
                    this._timer = -1;
                    this._hidden = true;
                    this.node.classList.add('lm-mod-hidden');
                    /* <DEPRECATED> */
                    this.node.classList.add('p-mod-hidden');
                    /* </DEPRECATED> */ return;
                }
                // Do nothing if a hide is already pending.
                if (this._timer !== -1) {
                    return;
                }
                // Otherwise setup the hide timer.
                this._timer = window.setTimeout(function () {
                    _this._timer = -1;
                    _this._hidden = true;
                    _this.node.classList.add('lm-mod-hidden');
                    /* <DEPRECATED> */
                    _this.node.classList.add('p-mod-hidden');
                    /* </DEPRECATED> */
                }, delay);
            };
            return Overlay;
        }());
        DockPanel.Overlay = Overlay;
        /**
         * The default implementation of `IRenderer`.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
            }
            /**
             * Create a new tab bar for use with a dock panel.
             *
             * @returns A new tab bar for a dock panel.
             */
            Renderer.prototype.createTabBar = function (document) {
                var bar = new exports.TabBar({ document: document });
                bar.addClass('lm-DockPanel-tabBar');
                /* <DEPRECATED> */
                bar.addClass('p-DockPanel-tabBar');
                /* </DEPRECATED> */
                return bar;
            };
            /**
             * Create a new handle node for use with a dock panel.
             *
             * @returns A new handle node for a dock panel.
             */
            Renderer.prototype.createHandle = function () {
                var handle = document.createElement('div');
                handle.className = 'lm-DockPanel-handle';
                /* <DEPRECATED> */
                handle.classList.add('p-DockPanel-handle');
                /* </DEPRECATED> */ return handle;
            };
            return Renderer;
        }());
        DockPanel.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        DockPanel.defaultRenderer = new Renderer();
    })(exports.DockPanel || (exports.DockPanel = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$5;
    (function (Private) {
        /**
         * A fraction used for sizing root panels; ~= `1 / golden_ratio`.
         */
        Private.GOLDEN_RATIO = 0.618;
        /**
         * The default sizes for the edge drop zones, in pixels.
         */
        Private.DEFAULT_EDGES = {
            /**
             * The size of the top edge dock zone for the root panel, in pixels.
             * This is different from the others to distinguish between the top
             * tab bar and the top root zone.
             */
            top: 12,
            /**
             * The size of the edge dock zone for the root panel, in pixels.
             */
            right: 40,
            /**
             * The size of the edge dock zone for the root panel, in pixels.
             */
            bottom: 40,
            /**
             * The size of the edge dock zone for the root panel, in pixels.
             */
            left: 40
        };
        /**
         * A singleton `'layout-modified'` conflatable message.
         */
        Private.LayoutModified = new messaging.ConflatableMessage('layout-modified');
        /**
         * An attached property used to track generated tab bars.
         */
        Private.isGeneratedTabBarProperty = new properties.AttachedProperty({
            name: 'isGeneratedTabBar',
            create: function () { return false; }
        });
        /**
         * Create a single document config for the widgets in a dock panel.
         */
        function createSingleDocumentConfig(panel) {
            // Return an empty config if the panel is empty.
            if (panel.isEmpty) {
                return { main: null };
            }
            // Get a flat array of the widgets in the panel.
            var widgets = algorithm.toArray(panel.widgets());
            // Get the first selected widget in the panel.
            var selected = panel.selectedWidgets().next();
            // Compute the current index for the new config.
            var currentIndex = selected ? widgets.indexOf(selected) : -1;
            // Return the single document config.
            return { main: { type: 'tab-area', widgets: widgets, currentIndex: currentIndex } };
        }
        Private.createSingleDocumentConfig = createSingleDocumentConfig;
        /**
         * Find the drop target at the given client position.
         */
        function findDropTarget(panel, clientX, clientY, edges) {
            // Bail if the mouse is not over the dock panel.
            if (!domutils.ElementExt.hitTest(panel.node, clientX, clientY)) {
                return { zone: 'invalid', target: null };
            }
            // Look up the layout for the panel.
            var layout = panel.layout;
            // If the layout is empty, indicate the entire root drop zone.
            if (layout.isEmpty) {
                return { zone: 'root-all', target: null };
            }
            // Test the edge zones when in multiple document mode.
            if (panel.mode === 'multiple-document') {
                // Get the client rect for the dock panel.
                var panelRect = panel.node.getBoundingClientRect();
                // Compute the distance to each edge of the panel.
                var pl = clientX - panelRect.left + 1;
                var pt = clientY - panelRect.top + 1;
                var pr = panelRect.right - clientX;
                var pb = panelRect.bottom - clientY;
                // Find the minimum distance to an edge.
                var pd = Math.min(pt, pr, pb, pl);
                // Return a root zone if the mouse is within an edge.
                switch (pd) {
                    case pt:
                        if (pt < edges.top) {
                            return { zone: 'root-top', target: null };
                        }
                        break;
                    case pr:
                        if (pr < edges.right) {
                            return { zone: 'root-right', target: null };
                        }
                        break;
                    case pb:
                        if (pb < edges.bottom) {
                            return { zone: 'root-bottom', target: null };
                        }
                        break;
                    case pl:
                        if (pl < edges.left) {
                            return { zone: 'root-left', target: null };
                        }
                        break;
                    default:
                        throw 'unreachable';
                }
            }
            // Hit test the dock layout at the given client position.
            var target = layout.hitTestTabAreas(clientX, clientY);
            // Bail if no target area was found.
            if (!target) {
                return { zone: 'invalid', target: null };
            }
            // Return the whole tab area when in single document mode.
            if (panel.mode === 'single-document') {
                return { zone: 'widget-all', target: target };
            }
            // Compute the distance to each edge of the tab area.
            var al = target.x - target.left + 1;
            var at = target.y - target.top + 1;
            var ar = target.left + target.width - target.x;
            var ab = target.top + target.height - target.y;
            var tabHeight = target.tabBar.node.getBoundingClientRect().height;
            if (at < tabHeight) {
                return { zone: 'widget-tab', target: target };
            }
            // Get the X and Y edge sizes for the area.
            var rx = Math.round(target.width / 3);
            var ry = Math.round(target.height / 3);
            // If the mouse is not within an edge, indicate the entire area.
            if (al > rx && ar > rx && at > ry && ab > ry) {
                return { zone: 'widget-all', target: target };
            }
            // Scale the distances by the slenderness ratio.
            al /= rx;
            at /= ry;
            ar /= rx;
            ab /= ry;
            // Find the minimum distance to the area edge.
            var ad = Math.min(al, at, ar, ab);
            // Find the widget zone for the area edge.
            var zone;
            switch (ad) {
                case al:
                    zone = 'widget-left';
                    break;
                case at:
                    zone = 'widget-top';
                    break;
                case ar:
                    zone = 'widget-right';
                    break;
                case ab:
                    zone = 'widget-bottom';
                    break;
                default:
                    throw 'unreachable';
            }
            // Return the final drop target.
            return { zone: zone, target: target };
        }
        Private.findDropTarget = findDropTarget;
        /**
         * Get the drop reference widget for a tab bar.
         */
        function getDropRef(tabBar) {
            if (tabBar.titles.length === 0) {
                return null;
            }
            if (tabBar.currentTitle) {
                return tabBar.currentTitle.owner;
            }
            return tabBar.titles[tabBar.titles.length - 1].owner;
        }
        Private.getDropRef = getDropRef;
    })(Private$5 || (Private$5 = {}));

    // Copyright (c) Jupyter Development Team.
    /**
     * A class which tracks focus among a set of widgets.
     *
     * This class is useful when code needs to keep track of the most
     * recently focused widget(s) among a set of related widgets.
     */
    var FocusTracker = /** @class */ (function () {
        function FocusTracker() {
            this._counter = 0;
            this._widgets = [];
            this._activeWidget = null;
            this._currentWidget = null;
            this._numbers = new Map();
            this._nodes = new Map();
            this._activeChanged = new signaling.Signal(this);
            this._currentChanged = new signaling.Signal(this);
        }
        /**
         * Dispose of the resources held by the tracker.
         */
        FocusTracker.prototype.dispose = function () {
            var _this = this;
            // Do nothing if the tracker is already disposed.
            if (this._counter < 0) {
                return;
            }
            // Mark the tracker as disposed.
            this._counter = -1;
            // Clear the connections for the tracker.
            signaling.Signal.clearData(this);
            // Remove all event listeners.
            algorithm.each(this._widgets, function (w) {
                w.node.removeEventListener('focus', _this, true);
                w.node.removeEventListener('blur', _this, true);
            });
            // Clear the internal data structures.
            this._activeWidget = null;
            this._currentWidget = null;
            this._nodes.clear();
            this._numbers.clear();
            this._widgets.length = 0;
        };
        Object.defineProperty(FocusTracker.prototype, "currentChanged", {
            /**
             * A signal emitted when the current widget has changed.
             */
            get: function () {
                return this._currentChanged;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(FocusTracker.prototype, "activeChanged", {
            /**
             * A signal emitted when the active widget has changed.
             */
            get: function () {
                return this._activeChanged;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(FocusTracker.prototype, "isDisposed", {
            /**
             * A flag indicating whether the tracker is disposed.
             */
            get: function () {
                return this._counter < 0;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(FocusTracker.prototype, "currentWidget", {
            /**
             * The current widget in the tracker.
             *
             * #### Notes
             * The current widget is the widget among the tracked widgets which
             * has the *descendant node* which has most recently been focused.
             *
             * The current widget will not be updated if the node loses focus. It
             * will only be updated when a different tracked widget gains focus.
             *
             * If the current widget is removed from the tracker, the previous
             * current widget will be restored.
             *
             * This behavior is intended to follow a user's conceptual model of
             * a semantically "current" widget, where the "last thing of type X"
             * to be interacted with is the "current instance of X", regardless
             * of whether that instance still has focus.
             */
            get: function () {
                return this._currentWidget;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(FocusTracker.prototype, "activeWidget", {
            /**
             * The active widget in the tracker.
             *
             * #### Notes
             * The active widget is the widget among the tracked widgets which
             * has the *descendant node* which is currently focused.
             */
            get: function () {
                return this._activeWidget;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(FocusTracker.prototype, "widgets", {
            /**
             * A read only array of the widgets being tracked.
             */
            get: function () {
                return this._widgets;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Get the focus number for a particular widget in the tracker.
         *
         * @param widget - The widget of interest.
         *
         * @returns The focus number for the given widget, or `-1` if the
         *   widget has not had focus since being added to the tracker, or
         *   is not contained by the tracker.
         *
         * #### Notes
         * The focus number indicates the relative order in which the widgets
         * have gained focus. A widget with a larger number has gained focus
         * more recently than a widget with a smaller number.
         *
         * The `currentWidget` will always have the largest focus number.
         *
         * All widgets start with a focus number of `-1`, which indicates that
         * the widget has not been focused since being added to the tracker.
         */
        FocusTracker.prototype.focusNumber = function (widget) {
            var n = this._numbers.get(widget);
            return n === undefined ? -1 : n;
        };
        /**
         * Test whether the focus tracker contains a given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns `true` if the widget is tracked, `false` otherwise.
         */
        FocusTracker.prototype.has = function (widget) {
            return this._numbers.has(widget);
        };
        /**
         * Add a widget to the focus tracker.
         *
         * @param widget - The widget of interest.
         *
         * #### Notes
         * A widget will be automatically removed from the tracker if it
         * is disposed after being added.
         *
         * If the widget is already tracked, this is a no-op.
         */
        FocusTracker.prototype.add = function (widget) {
            // Do nothing if the widget is already tracked.
            if (this._numbers.has(widget)) {
                return;
            }
            // Test whether the widget has focus.
            var focused = widget.node.contains(document.activeElement);
            // Set up the initial focus number.
            var n = focused ? this._counter++ : -1;
            // Add the widget to the internal data structures.
            this._widgets.push(widget);
            this._numbers.set(widget, n);
            this._nodes.set(widget.node, widget);
            // Set up the event listeners. The capturing phase must be used
            // since the 'focus' and 'blur' events don't bubble and Firefox
            // doesn't support the 'focusin' or 'focusout' events.
            widget.node.addEventListener('focus', this, true);
            widget.node.addEventListener('blur', this, true);
            // Connect the disposed signal handler.
            widget.disposed.connect(this._onWidgetDisposed, this);
            // Set the current and active widgets if needed.
            if (focused) {
                this._setWidgets(widget, widget);
            }
        };
        /**
         * Remove a widget from the focus tracker.
         *
         * #### Notes
         * If the widget is the `currentWidget`, the previous current widget
         * will become the new `currentWidget`.
         *
         * A widget will be automatically removed from the tracker if it
         * is disposed after being added.
         *
         * If the widget is not tracked, this is a no-op.
         */
        FocusTracker.prototype.remove = function (widget) {
            var _this = this;
            // Bail early if the widget is not tracked.
            if (!this._numbers.has(widget)) {
                return;
            }
            // Disconnect the disposed signal handler.
            widget.disposed.disconnect(this._onWidgetDisposed, this);
            // Remove the event listeners.
            widget.node.removeEventListener('focus', this, true);
            widget.node.removeEventListener('blur', this, true);
            // Remove the widget from the internal data structures.
            algorithm.ArrayExt.removeFirstOf(this._widgets, widget);
            this._nodes.delete(widget.node);
            this._numbers.delete(widget);
            // Bail early if the widget is not the current widget.
            if (this._currentWidget !== widget) {
                return;
            }
            // Filter the widgets for those which have had focus.
            var valid = algorithm.filter(this._widgets, function (w) { return _this._numbers.get(w) !== -1; });
            // Get the valid widget with the max focus number.
            var previous = algorithm.max(valid, function (first, second) {
                var a = _this._numbers.get(first);
                var b = _this._numbers.get(second);
                return a - b;
            }) || null;
            // Set the current and active widgets.
            this._setWidgets(previous, null);
        };
        /**
         * Handle the DOM events for the focus tracker.
         *
         * @param event - The DOM event sent to the panel.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the tracked nodes. It should
         * not be called directly by user code.
         */
        FocusTracker.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'focus':
                    this._evtFocus(event);
                    break;
                case 'blur':
                    this._evtBlur(event);
                    break;
            }
        };
        /**
         * Set the current and active widgets for the tracker.
         */
        FocusTracker.prototype._setWidgets = function (current, active) {
            // Swap the current widget.
            var oldCurrent = this._currentWidget;
            this._currentWidget = current;
            // Swap the active widget.
            var oldActive = this._activeWidget;
            this._activeWidget = active;
            // Emit the `currentChanged` signal if needed.
            if (oldCurrent !== current) {
                this._currentChanged.emit({ oldValue: oldCurrent, newValue: current });
            }
            // Emit the `activeChanged` signal if needed.
            if (oldActive !== active) {
                this._activeChanged.emit({ oldValue: oldActive, newValue: active });
            }
        };
        /**
         * Handle the `'focus'` event for a tracked widget.
         */
        FocusTracker.prototype._evtFocus = function (event) {
            // Find the widget which gained focus, which is known to exist.
            var widget = this._nodes.get(event.currentTarget);
            // Update the focus number if necessary.
            if (widget !== this._currentWidget) {
                this._numbers.set(widget, this._counter++);
            }
            // Set the current and active widgets.
            this._setWidgets(widget, widget);
        };
        /**
         * Handle the `'blur'` event for a tracked widget.
         */
        FocusTracker.prototype._evtBlur = function (event) {
            // Find the widget which lost focus, which is known to exist.
            var widget = this._nodes.get(event.currentTarget);
            // Get the node which being focused after this blur.
            var focusTarget = event.relatedTarget;
            // If no other node is being focused, clear the active widget.
            if (!focusTarget) {
                this._setWidgets(this._currentWidget, null);
                return;
            }
            // Bail if the focus widget is not changing.
            if (widget.node.contains(focusTarget)) {
                return;
            }
            // If no tracked widget is being focused, clear the active widget.
            if (!algorithm.find(this._widgets, function (w) { return w.node.contains(focusTarget); })) {
                this._setWidgets(this._currentWidget, null);
                return;
            }
        };
        /**
         * Handle the `disposed` signal for a tracked widget.
         */
        FocusTracker.prototype._onWidgetDisposed = function (sender) {
            this.remove(sender);
        };
        return FocusTracker;
    }());

    /**
     * A layout which arranges its widgets in a grid.
     */
    exports.GridLayout = /** @class */ (function (_super) {
        __extends(GridLayout, _super);
        /**
         * Construct a new grid layout.
         *
         * @param options - The options for initializing the layout.
         */
        function GridLayout(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, options) || this;
            _this._dirty = false;
            _this._rowSpacing = 4;
            _this._columnSpacing = 4;
            _this._items = [];
            _this._rowStarts = [];
            _this._columnStarts = [];
            _this._rowSizers = [new BoxSizer()];
            _this._columnSizers = [new BoxSizer()];
            _this._box = null;
            if (options.rowCount !== undefined) {
                Private$4.reallocSizers(_this._rowSizers, options.rowCount);
            }
            if (options.columnCount !== undefined) {
                Private$4.reallocSizers(_this._columnSizers, options.columnCount);
            }
            if (options.rowSpacing !== undefined) {
                _this._rowSpacing = Private$4.clampValue(options.rowSpacing);
            }
            if (options.columnSpacing !== undefined) {
                _this._columnSpacing = Private$4.clampValue(options.columnSpacing);
            }
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         */
        GridLayout.prototype.dispose = function () {
            // Dispose of the widgets and layout items.
            algorithm.each(this._items, function (item) {
                var widget = item.widget;
                item.dispose();
                widget.dispose();
            });
            // Clear the layout state.
            this._box = null;
            this._items.length = 0;
            this._rowStarts.length = 0;
            this._rowSizers.length = 0;
            this._columnStarts.length = 0;
            this._columnSizers.length = 0;
            // Dispose of the rest of the layout.
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(GridLayout.prototype, "rowCount", {
            /**
             * Get the number of rows in the layout.
             */
            get: function () {
                return this._rowSizers.length;
            },
            /**
             * Set the number of rows in the layout.
             *
             * #### Notes
             * The minimum row count is `1`.
             */
            set: function (value) {
                // Do nothing if the row count does not change.
                if (value === this.rowCount) {
                    return;
                }
                // Reallocate the row sizers.
                Private$4.reallocSizers(this._rowSizers, value);
                // Schedule a fit of the parent.
                if (this.parent) {
                    this.parent.fit();
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(GridLayout.prototype, "columnCount", {
            /**
             * Get the number of columns in the layout.
             */
            get: function () {
                return this._columnSizers.length;
            },
            /**
             * Set the number of columns in the layout.
             *
             * #### Notes
             * The minimum column count is `1`.
             */
            set: function (value) {
                // Do nothing if the column count does not change.
                if (value === this.columnCount) {
                    return;
                }
                // Reallocate the column sizers.
                Private$4.reallocSizers(this._columnSizers, value);
                // Schedule a fit of the parent.
                if (this.parent) {
                    this.parent.fit();
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(GridLayout.prototype, "rowSpacing", {
            /**
             * Get the row spacing for the layout.
             */
            get: function () {
                return this._rowSpacing;
            },
            /**
             * Set the row spacing for the layout.
             */
            set: function (value) {
                // Clamp the spacing to the allowed range.
                value = Private$4.clampValue(value);
                // Bail if the spacing does not change
                if (this._rowSpacing === value) {
                    return;
                }
                // Update the internal spacing.
                this._rowSpacing = value;
                // Schedule a fit of the parent.
                if (this.parent) {
                    this.parent.fit();
                }
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(GridLayout.prototype, "columnSpacing", {
            /**
             * Get the column spacing for the layout.
             */
            get: function () {
                return this._columnSpacing;
            },
            /**
             * Set the col spacing for the layout.
             */
            set: function (value) {
                // Clamp the spacing to the allowed range.
                value = Private$4.clampValue(value);
                // Bail if the spacing does not change
                if (this._columnSpacing === value) {
                    return;
                }
                // Update the internal spacing.
                this._columnSpacing = value;
                // Schedule a fit of the parent.
                if (this.parent) {
                    this.parent.fit();
                }
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Get the stretch factor for a specific row.
         *
         * @param index - The row index of interest.
         *
         * @returns The stretch factor for the row.
         *
         * #### Notes
         * This returns `-1` if the index is out of range.
         */
        GridLayout.prototype.rowStretch = function (index) {
            var sizer = this._rowSizers[index];
            return sizer ? sizer.stretch : -1;
        };
        /**
         * Set the stretch factor for a specific row.
         *
         * @param index - The row index of interest.
         *
         * @param value - The stretch factor for the row.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        GridLayout.prototype.setRowStretch = function (index, value) {
            // Look up the row sizer.
            var sizer = this._rowSizers[index];
            // Bail if the index is out of range.
            if (!sizer) {
                return;
            }
            // Clamp the value to the allowed range.
            value = Private$4.clampValue(value);
            // Bail if the stretch does not change.
            if (sizer.stretch === value) {
                return;
            }
            // Update the sizer stretch.
            sizer.stretch = value;
            // Schedule an update of the parent.
            if (this.parent) {
                this.parent.update();
            }
        };
        /**
         * Get the stretch factor for a specific column.
         *
         * @param index - The column index of interest.
         *
         * @returns The stretch factor for the column.
         *
         * #### Notes
         * This returns `-1` if the index is out of range.
         */
        GridLayout.prototype.columnStretch = function (index) {
            var sizer = this._columnSizers[index];
            return sizer ? sizer.stretch : -1;
        };
        /**
         * Set the stretch factor for a specific column.
         *
         * @param index - The column index of interest.
         *
         * @param value - The stretch factor for the column.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        GridLayout.prototype.setColumnStretch = function (index, value) {
            // Look up the column sizer.
            var sizer = this._columnSizers[index];
            // Bail if the index is out of range.
            if (!sizer) {
                return;
            }
            // Clamp the value to the allowed range.
            value = Private$4.clampValue(value);
            // Bail if the stretch does not change.
            if (sizer.stretch === value) {
                return;
            }
            // Update the sizer stretch.
            sizer.stretch = value;
            // Schedule an update of the parent.
            if (this.parent) {
                this.parent.update();
            }
        };
        /**
         * Create an iterator over the widgets in the layout.
         *
         * @returns A new iterator over the widgets in the layout.
         */
        GridLayout.prototype.iter = function () {
            return algorithm.map(this._items, function (item) { return item.widget; });
        };
        /**
         * Add a widget to the grid layout.
         *
         * @param widget - The widget to add to the layout.
         *
         * #### Notes
         * If the widget is already contained in the layout, this is no-op.
         */
        GridLayout.prototype.addWidget = function (widget) {
            // Look up the index for the widget.
            var i = algorithm.ArrayExt.findFirstIndex(this._items, function (it) { return it.widget === widget; });
            // Bail if the widget is already in the layout.
            if (i !== -1) {
                return;
            }
            // Add the widget to the layout.
            this._items.push(new LayoutItem(widget));
            // Attach the widget to the parent.
            if (this.parent) {
                this.attachWidget(widget);
            }
        };
        /**
         * Remove a widget from the grid layout.
         *
         * @param widget - The widget to remove from the layout.
         *
         * #### Notes
         * A widget is automatically removed from the layout when its `parent`
         * is set to `null`. This method should only be invoked directly when
         * removing a widget from a layout which has yet to be installed on a
         * parent widget.
         *
         * This method does *not* modify the widget's `parent`.
         */
        GridLayout.prototype.removeWidget = function (widget) {
            // Look up the index for the widget.
            var i = algorithm.ArrayExt.findFirstIndex(this._items, function (it) { return it.widget === widget; });
            // Bail if the widget is not in the layout.
            if (i === -1) {
                return;
            }
            // Remove the widget from the layout.
            var item = algorithm.ArrayExt.removeAt(this._items, i);
            // Detach the widget from the parent.
            if (this.parent) {
                this.detachWidget(widget);
            }
            // Dispose the layout item.
            item.dispose();
        };
        /**
         * Perform layout initialization which requires the parent widget.
         */
        GridLayout.prototype.init = function () {
            var _this = this;
            _super.prototype.init.call(this);
            algorithm.each(this, function (widget) {
                _this.attachWidget(widget);
            });
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param widget - The widget to attach to the parent.
         */
        GridLayout.prototype.attachWidget = function (widget) {
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget's node to the parent.
            this.parent.node.appendChild(widget.node);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param widget - The widget to detach from the parent.
         */
        GridLayout.prototype.detachWidget = function (widget) {
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         */
        GridLayout.prototype.onBeforeShow = function (msg) {
            _super.prototype.onBeforeShow.call(this, msg);
            this.parent.update();
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        GridLayout.prototype.onBeforeAttach = function (msg) {
            _super.prototype.onBeforeAttach.call(this, msg);
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-shown'` message.
         */
        GridLayout.prototype.onChildShown = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         */
        GridLayout.prototype.onChildHidden = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'resize'` message.
         */
        GridLayout.prototype.onResize = function (msg) {
            if (this.parent.isVisible) {
                this._update(msg.width, msg.height);
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        GridLayout.prototype.onUpdateRequest = function (msg) {
            if (this.parent.isVisible) {
                this._update(-1, -1);
            }
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         */
        GridLayout.prototype.onFitRequest = function (msg) {
            if (this.parent.isAttached) {
                this._fit();
            }
        };
        /**
         * Fit the layout to the total size required by the widgets.
         */
        GridLayout.prototype._fit = function () {
            // Reset the min sizes of the sizers.
            for (var i = 0, n = this.rowCount; i < n; ++i) {
                this._rowSizers[i].minSize = 0;
            }
            for (var i = 0, n = this.columnCount; i < n; ++i) {
                this._columnSizers[i].minSize = 0;
            }
            // Filter for the visible layout items.
            var items = this._items.filter(function (it) { return !it.isHidden; });
            // Fit the layout items.
            for (var i = 0, n = items.length; i < n; ++i) {
                items[i].fit();
            }
            // Get the max row and column index.
            var maxRow = this.rowCount - 1;
            var maxCol = this.columnCount - 1;
            // Sort the items by row span.
            items.sort(Private$4.rowSpanCmp);
            // Update the min sizes of the row sizers.
            for (var i = 0, n = items.length; i < n; ++i) {
                // Fetch the item.
                var item = items[i];
                // Get the row bounds for the item.
                var config = GridLayout.getCellConfig(item.widget);
                var r1 = Math.min(config.row, maxRow);
                var r2 = Math.min(config.row + config.rowSpan - 1, maxRow);
                // Distribute the minimum height to the sizers as needed.
                Private$4.distributeMin(this._rowSizers, r1, r2, item.minHeight);
            }
            // Sort the items by column span.
            items.sort(Private$4.columnSpanCmp);
            // Update the min sizes of the column sizers.
            for (var i = 0, n = items.length; i < n; ++i) {
                // Fetch the item.
                var item = items[i];
                // Get the column bounds for the item.
                var config = GridLayout.getCellConfig(item.widget);
                var c1 = Math.min(config.column, maxCol);
                var c2 = Math.min(config.column + config.columnSpan - 1, maxCol);
                // Distribute the minimum width to the sizers as needed.
                Private$4.distributeMin(this._columnSizers, c1, c2, item.minWidth);
            }
            // If no size constraint is needed, just update the parent.
            if (this.fitPolicy === 'set-no-constraint') {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
                return;
            }
            // Set up the computed min size.
            var minH = maxRow * this._rowSpacing;
            var minW = maxCol * this._columnSpacing;
            // Add the sizer minimums to the computed min size.
            for (var i = 0, n = this.rowCount; i < n; ++i) {
                minH += this._rowSizers[i].minSize;
            }
            for (var i = 0, n = this.columnCount; i < n; ++i) {
                minW += this._columnSizers[i].minSize;
            }
            // Update the box sizing and add it to the computed min size.
            var box = (this._box = domutils.ElementExt.boxSizing(this.parent.node));
            minW += box.horizontalSum;
            minH += box.verticalSum;
            // Update the parent's min size constraints.
            var style = this.parent.node.style;
            style.minWidth = minW + "px";
            style.minHeight = minH + "px";
            // Set the dirty flag to ensure only a single update occurs.
            this._dirty = true;
            // Notify the ancestor that it should fit immediately. This may
            // cause a resize of the parent, fulfilling the required update.
            if (this.parent.parent) {
                messaging.MessageLoop.sendMessage(this.parent.parent, exports.Widget.Msg.FitRequest);
            }
            // If the dirty flag is still set, the parent was not resized.
            // Trigger the required update on the parent widget immediately.
            if (this._dirty) {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
            }
        };
        /**
         * Update the layout position and size of the widgets.
         *
         * The parent offset dimensions should be `-1` if unknown.
         */
        GridLayout.prototype._update = function (offsetWidth, offsetHeight) {
            // Clear the dirty flag to indicate the update occurred.
            this._dirty = false;
            // Measure the parent if the offset dimensions are unknown.
            if (offsetWidth < 0) {
                offsetWidth = this.parent.node.offsetWidth;
            }
            if (offsetHeight < 0) {
                offsetHeight = this.parent.node.offsetHeight;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Compute the layout area adjusted for border and padding.
            var top = this._box.paddingTop;
            var left = this._box.paddingLeft;
            var width = offsetWidth - this._box.horizontalSum;
            var height = offsetHeight - this._box.verticalSum;
            // Get the max row and column index.
            var maxRow = this.rowCount - 1;
            var maxCol = this.columnCount - 1;
            // Compute the total fixed row and column space.
            var fixedRowSpace = maxRow * this._rowSpacing;
            var fixedColSpace = maxCol * this._columnSpacing;
            // Distribute the available space to the box sizers.
            exports.BoxEngine.calc(this._rowSizers, Math.max(0, height - fixedRowSpace));
            exports.BoxEngine.calc(this._columnSizers, Math.max(0, width - fixedColSpace));
            // Update the row start positions.
            for (var i = 0, pos = top, n = this.rowCount; i < n; ++i) {
                this._rowStarts[i] = pos;
                pos += this._rowSizers[i].size + this._rowSpacing;
            }
            // Update the column start positions.
            for (var i = 0, pos = left, n = this.columnCount; i < n; ++i) {
                this._columnStarts[i] = pos;
                pos += this._columnSizers[i].size + this._columnSpacing;
            }
            // Update the geometry of the layout items.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item.
                var item = this._items[i];
                // Ignore hidden items.
                if (item.isHidden) {
                    continue;
                }
                // Fetch the cell bounds for the widget.
                var config = GridLayout.getCellConfig(item.widget);
                var r1 = Math.min(config.row, maxRow);
                var c1 = Math.min(config.column, maxCol);
                var r2 = Math.min(config.row + config.rowSpan - 1, maxRow);
                var c2 = Math.min(config.column + config.columnSpan - 1, maxCol);
                // Compute the cell geometry.
                var x = this._columnStarts[c1];
                var y = this._rowStarts[r1];
                var w = this._columnStarts[c2] + this._columnSizers[c2].size - x;
                var h = this._rowStarts[r2] + this._rowSizers[r2].size - y;
                // Update the geometry of the layout item.
                item.update(x, y, w, h);
            }
        };
        return GridLayout;
    }(exports.Layout));
    /**
     * The namespace for the `GridLayout` class statics.
     */
    (function (GridLayout) {
        /**
         * Get the cell config for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @returns The cell config for the widget.
         */
        function getCellConfig(widget) {
            return Private$4.cellConfigProperty.get(widget);
        }
        GridLayout.getCellConfig = getCellConfig;
        /**
         * Set the cell config for the given widget.
         *
         * @param widget - The widget of interest.
         *
         * @param value - The value for the cell config.
         */
        function setCellConfig(widget, value) {
            Private$4.cellConfigProperty.set(widget, Private$4.normalizeConfig(value));
        }
        GridLayout.setCellConfig = setCellConfig;
    })(exports.GridLayout || (exports.GridLayout = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$4;
    (function (Private) {
        /**
         * The property descriptor for the widget cell config.
         */
        Private.cellConfigProperty = new properties.AttachedProperty({
            name: 'cellConfig',
            create: function () { return ({ row: 0, column: 0, rowSpan: 1, columnSpan: 1 }); },
            changed: onChildCellConfigChanged
        });
        /**
         * Normalize a partial cell config object.
         */
        function normalizeConfig(config) {
            var row = Math.max(0, Math.floor(config.row || 0));
            var column = Math.max(0, Math.floor(config.column || 0));
            var rowSpan = Math.max(1, Math.floor(config.rowSpan || 0));
            var columnSpan = Math.max(1, Math.floor(config.columnSpan || 0));
            return { row: row, column: column, rowSpan: rowSpan, columnSpan: columnSpan };
        }
        Private.normalizeConfig = normalizeConfig;
        /**
         * Clamp a value to an integer >= 0.
         */
        function clampValue(value) {
            return Math.max(0, Math.floor(value));
        }
        Private.clampValue = clampValue;
        /**
         * A sort comparison function for row spans.
         */
        function rowSpanCmp(a, b) {
            var c1 = Private.cellConfigProperty.get(a.widget);
            var c2 = Private.cellConfigProperty.get(b.widget);
            return c1.rowSpan - c2.rowSpan;
        }
        Private.rowSpanCmp = rowSpanCmp;
        /**
         * A sort comparison function for column spans.
         */
        function columnSpanCmp(a, b) {
            var c1 = Private.cellConfigProperty.get(a.widget);
            var c2 = Private.cellConfigProperty.get(b.widget);
            return c1.columnSpan - c2.columnSpan;
        }
        Private.columnSpanCmp = columnSpanCmp;
        /**
         * Reallocate the box sizers for the given grid dimensions.
         */
        function reallocSizers(sizers, count) {
            // Coerce the count to the valid range.
            count = Math.max(1, Math.floor(count));
            // Add the missing sizers.
            while (sizers.length < count) {
                sizers.push(new BoxSizer());
            }
            // Remove the extra sizers.
            if (sizers.length > count) {
                sizers.length = count;
            }
        }
        Private.reallocSizers = reallocSizers;
        /**
         * Distribute a min size constraint across a range of sizers.
         */
        function distributeMin(sizers, i1, i2, minSize) {
            // Sanity check the indices.
            if (i2 < i1) {
                return;
            }
            // Handle the simple case of no cell span.
            if (i1 === i2) {
                var sizer = sizers[i1];
                sizer.minSize = Math.max(sizer.minSize, minSize);
                return;
            }
            // Compute the total current min size of the span.
            var totalMin = 0;
            for (var i = i1; i <= i2; ++i) {
                totalMin += sizers[i].minSize;
            }
            // Do nothing if the total is greater than the required.
            if (totalMin >= minSize) {
                return;
            }
            // Compute the portion of the space to allocate to each sizer.
            var portion = (minSize - totalMin) / (i2 - i1 + 1);
            // Add the portion to each sizer.
            for (var i = i1; i <= i2; ++i) {
                sizers[i].minSize += portion;
            }
        }
        Private.distributeMin = distributeMin;
        /**
         * The change handler for the child cell config property.
         */
        function onChildCellConfigChanged(child) {
            if (child.parent && child.parent.layout instanceof exports.GridLayout) {
                child.parent.fit();
            }
        }
    })(Private$4 || (Private$4 = {}));

    /**
     * A widget which displays menus as a canonical menu bar.
     */
    exports.MenuBar = /** @class */ (function (_super) {
        __extends(MenuBar, _super);
        /**
         * Construct a new menu bar.
         *
         * @param options - The options for initializing the menu bar.
         */
        function MenuBar(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { node: Private$3.createNode() }) || this;
            _this._activeIndex = -1;
            _this._menus = [];
            _this._childMenu = null;
            _this.addClass('lm-MenuBar');
            /* <DEPRECATED> */
            _this.addClass('p-MenuBar');
            /* </DEPRECATED> */
            _this.setFlag(exports.Widget.Flag.DisallowLayout);
            _this.renderer = options.renderer || MenuBar.defaultRenderer;
            _this._forceItemsPosition = options.forceItemsPosition || {
                forceX: true,
                forceY: true
            };
            return _this;
        }
        /**
         * Dispose of the resources held by the widget.
         */
        MenuBar.prototype.dispose = function () {
            this._closeChildMenu();
            this._menus.length = 0;
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(MenuBar.prototype, "childMenu", {
            /**
             * The child menu of the menu bar.
             *
             * #### Notes
             * This will be `null` if the menu bar does not have an open menu.
             */
            get: function () {
                return this._childMenu;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(MenuBar.prototype, "contentNode", {
            /**
             * Get the menu bar content node.
             *
             * #### Notes
             * This is the node which holds the menu title nodes.
             *
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-MenuBar-content')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(MenuBar.prototype, "activeMenu", {
            /**
             * Get the currently active menu.
             */
            get: function () {
                return this._menus[this._activeIndex] || null;
            },
            /**
             * Set the currently active menu.
             *
             * #### Notes
             * If the menu does not exist, the menu will be set to `null`.
             */
            set: function (value) {
                this.activeIndex = value ? this._menus.indexOf(value) : -1;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(MenuBar.prototype, "activeIndex", {
            /**
             * Get the index of the currently active menu.
             *
             * #### Notes
             * This will be `-1` if no menu is active.
             */
            get: function () {
                return this._activeIndex;
            },
            /**
             * Set the index of the currently active menu.
             *
             * #### Notes
             * If the menu cannot be activated, the index will be set to `-1`.
             */
            set: function (value) {
                // Adjust the value for an out of range index.
                if (value < 0 || value >= this._menus.length) {
                    value = -1;
                }
                // Bail early if the index will not change.
                if (this._activeIndex === value) {
                    return;
                }
                // Update the active index.
                this._activeIndex = value;
                // Update focus to new active index
                if (this._activeIndex >= 0 &&
                    this.contentNode.childNodes[this._activeIndex]) {
                    this.contentNode.childNodes[this._activeIndex].focus();
                }
                // Schedule an update of the items.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(MenuBar.prototype, "menus", {
            /**
             * A read-only array of the menus in the menu bar.
             */
            get: function () {
                return this._menus;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Open the active menu and activate its first menu item.
         *
         * #### Notes
         * If there is no active menu, this is a no-op.
         */
        MenuBar.prototype.openActiveMenu = function () {
            // Bail early if there is no active item.
            if (this._activeIndex === -1) {
                return;
            }
            // Open the child menu.
            this._openChildMenu();
            // Activate the first item in the child menu.
            if (this._childMenu) {
                this._childMenu.activeIndex = -1;
                this._childMenu.activateNextItem();
            }
        };
        /**
         * Add a menu to the end of the menu bar.
         *
         * @param menu - The menu to add to the menu bar.
         *
         * #### Notes
         * If the menu is already added to the menu bar, it will be moved.
         */
        MenuBar.prototype.addMenu = function (menu) {
            this.insertMenu(this._menus.length, menu);
        };
        /**
         * Insert a menu into the menu bar at the specified index.
         *
         * @param index - The index at which to insert the menu.
         *
         * @param menu - The menu to insert into the menu bar.
         *
         * #### Notes
         * The index will be clamped to the bounds of the menus.
         *
         * If the menu is already added to the menu bar, it will be moved.
         */
        MenuBar.prototype.insertMenu = function (index, menu) {
            // Close the child menu before making changes.
            this._closeChildMenu();
            // Look up the index of the menu.
            var i = this._menus.indexOf(menu);
            // Clamp the insert index to the array bounds.
            var j = Math.max(0, Math.min(index, this._menus.length));
            // If the menu is not in the array, insert it.
            if (i === -1) {
                // Insert the menu into the array.
                algorithm.ArrayExt.insert(this._menus, j, menu);
                // Add the styling class to the menu.
                menu.addClass('lm-MenuBar-menu');
                /* <DEPRECATED> */
                menu.addClass('p-MenuBar-menu');
                /* </DEPRECATED> */
                // Connect to the menu signals.
                menu.aboutToClose.connect(this._onMenuAboutToClose, this);
                menu.menuRequested.connect(this._onMenuMenuRequested, this);
                menu.title.changed.connect(this._onTitleChanged, this);
                // Schedule an update of the items.
                this.update();
                // There is nothing more to do.
                return;
            }
            // Otherwise, the menu exists in the array and should be moved.
            // Adjust the index if the location is at the end of the array.
            if (j === this._menus.length) {
                j--;
            }
            // Bail if there is no effective move.
            if (i === j) {
                return;
            }
            // Move the menu to the new locations.
            algorithm.ArrayExt.move(this._menus, i, j);
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Remove a menu from the menu bar.
         *
         * @param menu - The menu to remove from the menu bar.
         *
         * #### Notes
         * This is a no-op if the menu is not in the menu bar.
         */
        MenuBar.prototype.removeMenu = function (menu) {
            this.removeMenuAt(this._menus.indexOf(menu));
        };
        /**
         * Remove the menu at a given index from the menu bar.
         *
         * @param index - The index of the menu to remove.
         *
         * #### Notes
         * This is a no-op if the index is out of range.
         */
        MenuBar.prototype.removeMenuAt = function (index) {
            // Close the child menu before making changes.
            this._closeChildMenu();
            // Remove the menu from the array.
            var menu = algorithm.ArrayExt.removeAt(this._menus, index);
            // Bail if the index is out of range.
            if (!menu) {
                return;
            }
            // Disconnect from the menu signals.
            menu.aboutToClose.disconnect(this._onMenuAboutToClose, this);
            menu.menuRequested.disconnect(this._onMenuMenuRequested, this);
            menu.title.changed.disconnect(this._onTitleChanged, this);
            // Remove the styling class from the menu.
            menu.removeClass('lm-MenuBar-menu');
            /* <DEPRECATED> */
            menu.removeClass('p-MenuBar-menu');
            /* </DEPRECATED> */
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Remove all menus from the menu bar.
         */
        MenuBar.prototype.clearMenus = function () {
            // Bail if there is nothing to remove.
            if (this._menus.length === 0) {
                return;
            }
            // Close the child menu before making changes.
            this._closeChildMenu();
            // Disconnect from the menu signals and remove the styling class.
            for (var _i = 0, _a = this._menus; _i < _a.length; _i++) {
                var menu = _a[_i];
                menu.aboutToClose.disconnect(this._onMenuAboutToClose, this);
                menu.menuRequested.disconnect(this._onMenuMenuRequested, this);
                menu.title.changed.disconnect(this._onTitleChanged, this);
                menu.removeClass('lm-MenuBar-menu');
                /* <DEPRECATED> */
                menu.removeClass('p-MenuBar-menu');
                /* </DEPRECATED> */
            }
            // Clear the menus array.
            this._menus.length = 0;
            // Schedule an update of the items.
            this.update();
        };
        /**
         * Handle the DOM events for the menu bar.
         *
         * @param event - The DOM event sent to the menu bar.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the menu bar's DOM nodes. It
         * should not be called directly by user code.
         */
        MenuBar.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'mousedown':
                    this._evtMouseDown(event);
                    break;
                case 'mousemove':
                    this._evtMouseMove(event);
                    break;
                case 'mouseleave':
                    this._evtMouseLeave(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        MenuBar.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('keydown', this);
            this.node.addEventListener('mousedown', this);
            this.node.addEventListener('mousemove', this);
            this.node.addEventListener('mouseleave', this);
            this.node.addEventListener('contextmenu', this);
        };
        /**
         * A message handler invoked on an `'after-detach'` message.
         */
        MenuBar.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('keydown', this);
            this.node.removeEventListener('mousedown', this);
            this.node.removeEventListener('mousemove', this);
            this.node.removeEventListener('mouseleave', this);
            this.node.removeEventListener('contextmenu', this);
            this._closeChildMenu();
        };
        /**
         * A message handler invoked on an `'activate-request'` message.
         */
        MenuBar.prototype.onActivateRequest = function (msg) {
            if (this.isAttached) {
                this.node.focus();
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        MenuBar.prototype.onUpdateRequest = function (msg) {
            var _this = this;
            var menus = this._menus;
            var renderer = this.renderer;
            var activeIndex = this._activeIndex;
            var content = new Array(menus.length);
            var _loop_1 = function (i, n) {
                var title = menus[i].title;
                var active = i === activeIndex;
                if (active && menus[i].items.length == 0) {
                    active = false;
                }
                content[i] = renderer.renderItem({
                    title: title,
                    active: active,
                    onfocus: function () {
                        _this.activeIndex = i;
                    }
                });
            };
            for (var i = 0, n = menus.length; i < n; ++i) {
                _loop_1(i);
            }
            virtualdom.VirtualDOM.render(content, this.contentNode);
        };
        /**
         * Handle the `'keydown'` event for the menu bar.
         */
        MenuBar.prototype._evtKeyDown = function (event) {
            // A menu bar handles all keydown events.
            event.preventDefault();
            event.stopPropagation();
            // Fetch the key code for the event.
            var kc = event.keyCode;
            // Enter, Up Arrow, Down Arrow
            if (kc === 13 || kc === 38 || kc === 40) {
                this.openActiveMenu();
                return;
            }
            // Escape
            if (kc === 27) {
                this._closeChildMenu();
                this.activeIndex = -1;
                this.node.blur();
                return;
            }
            // Left Arrow
            if (kc === 37) {
                var i = this._activeIndex;
                var n = this._menus.length;
                this.activeIndex = i === 0 ? n - 1 : i - 1;
                return;
            }
            // Right Arrow
            if (kc === 39) {
                var i = this._activeIndex;
                var n = this._menus.length;
                this.activeIndex = i === n - 1 ? 0 : i + 1;
                return;
            }
            // Get the pressed key character.
            var key = keyboard.getKeyboardLayout().keyForKeydownEvent(event);
            // Bail if the key is not valid.
            if (!key) {
                return;
            }
            // Search for the next best matching mnemonic item.
            var start = this._activeIndex + 1;
            var result = Private$3.findMnemonic(this._menus, key, start);
            // Handle the requested mnemonic based on the search results.
            // If exactly one mnemonic is matched, that menu is opened.
            // Otherwise, the next mnemonic is activated if available,
            // followed by the auto mnemonic if available.
            if (result.index !== -1 && !result.multiple) {
                this.activeIndex = result.index;
                this.openActiveMenu();
            }
            else if (result.index !== -1) {
                this.activeIndex = result.index;
            }
            else if (result.auto !== -1) {
                this.activeIndex = result.auto;
            }
        };
        /**
         * Handle the `'mousedown'` event for the menu bar.
         */
        MenuBar.prototype._evtMouseDown = function (event) {
            // Bail if the mouse press was not on the menu bar. This can occur
            // when the document listener is installed for an active menu bar.
            if (!domutils.ElementExt.hitTest(this.node, event.clientX, event.clientY)) {
                return;
            }
            // Stop the propagation of the event. Immediate propagation is
            // also stopped so that an open menu does not handle the event.
            event.preventDefault();
            event.stopPropagation();
            event.stopImmediatePropagation();
            // Check if the mouse is over one of the menu items.
            var index = algorithm.ArrayExt.findFirstIndex(this.contentNode.children, function (node) {
                return domutils.ElementExt.hitTest(node, event.clientX, event.clientY);
            });
            // If the press was not on an item, close the child menu.
            if (index === -1) {
                this._closeChildMenu();
                return;
            }
            // If the press was not the left mouse button, do nothing further.
            if (event.button !== 0) {
                return;
            }
            // Otherwise, toggle the open state of the child menu.
            if (this._childMenu) {
                this._closeChildMenu();
                this.activeIndex = index;
            }
            else {
                this.activeIndex = index;
                this._openChildMenu();
            }
        };
        /**
         * Handle the `'mousemove'` event for the menu bar.
         */
        MenuBar.prototype._evtMouseMove = function (event) {
            // Check if the mouse is over one of the menu items.
            var index = algorithm.ArrayExt.findFirstIndex(this.contentNode.children, function (node) {
                return domutils.ElementExt.hitTest(node, event.clientX, event.clientY);
            });
            // Bail early if the active index will not change.
            if (index === this._activeIndex) {
                return;
            }
            // Bail early if a child menu is open and the mouse is not over
            // an item. This allows the child menu to be kept open when the
            // mouse is over the empty part of the menu bar.
            if (index === -1 && this._childMenu) {
                return;
            }
            // Update the active index to the hovered item.
            this.activeIndex = index;
            // Open the new menu if a menu is already open.
            if (this._childMenu) {
                this._openChildMenu();
            }
        };
        /**
         * Handle the `'mouseleave'` event for the menu bar.
         */
        MenuBar.prototype._evtMouseLeave = function (event) {
            // Reset the active index if there is no open menu.
            if (!this._childMenu) {
                this.activeIndex = -1;
            }
        };
        /**
         * Open the child menu at the active index immediately.
         *
         * If a different child menu is already open, it will be closed,
         * even if there is no active menu.
         */
        MenuBar.prototype._openChildMenu = function () {
            // If there is no active menu, close the current menu.
            var newMenu = this.activeMenu;
            if (!newMenu) {
                this._closeChildMenu();
                return;
            }
            // Bail if there is no effective menu change.
            var oldMenu = this._childMenu;
            if (oldMenu === newMenu) {
                return;
            }
            // Swap the internal menu reference.
            this._childMenu = newMenu;
            // Close the current menu, or setup for the new menu.
            if (oldMenu) {
                oldMenu.close();
            }
            else {
                this.addClass('lm-mod-active');
                /* <DEPRECATED> */
                this.addClass('p-mod-active');
                /* </DEPRECATED> */
                document.addEventListener('mousedown', this, true);
            }
            // Ensure the menu bar is updated and look up the item node.
            messaging.MessageLoop.sendMessage(this, exports.Widget.Msg.UpdateRequest);
            var itemNode = this.contentNode.children[this._activeIndex];
            // Get the positioning data for the new menu.
            var _a = itemNode.getBoundingClientRect(), left = _a.left, bottom = _a.bottom;
            // Open the new menu at the computed location.
            if (newMenu.items.length > 0) {
                newMenu.open(left, bottom, this._forceItemsPosition);
            }
        };
        /**
         * Close the child menu immediately.
         *
         * This is a no-op if a child menu is not open.
         */
        MenuBar.prototype._closeChildMenu = function () {
            // Bail if no child menu is open.
            if (!this._childMenu) {
                return;
            }
            // Remove the active class from the menu bar.
            this.removeClass('lm-mod-active');
            /* <DEPRECATED> */
            this.removeClass('p-mod-active');
            /* </DEPRECATED> */
            // Remove the document listeners.
            document.removeEventListener('mousedown', this, true);
            // Clear the internal menu reference.
            var menu = this._childMenu;
            this._childMenu = null;
            // Close the menu.
            menu.close();
            // Reset the active index.
            this.activeIndex = -1;
        };
        /**
         * Handle the `aboutToClose` signal of a menu.
         */
        MenuBar.prototype._onMenuAboutToClose = function (sender) {
            // Bail if the sender is not the child menu.
            if (sender !== this._childMenu) {
                return;
            }
            // Remove the active class from the menu bar.
            this.removeClass('lm-mod-active');
            /* <DEPRECATED> */
            this.removeClass('p-mod-active');
            /* </DEPRECATED> */
            // Remove the document listeners.
            document.removeEventListener('mousedown', this, true);
            // Clear the internal menu reference.
            this._childMenu = null;
            // Reset the active index.
            this.activeIndex = -1;
        };
        /**
         * Handle the `menuRequested` signal of a child menu.
         */
        MenuBar.prototype._onMenuMenuRequested = function (sender, args) {
            // Bail if the sender is not the child menu.
            if (sender !== this._childMenu) {
                return;
            }
            // Look up the active index and menu count.
            var i = this._activeIndex;
            var n = this._menus.length;
            // Active the next requested index.
            switch (args) {
                case 'next':
                    this.activeIndex = i === n - 1 ? 0 : i + 1;
                    break;
                case 'previous':
                    this.activeIndex = i === 0 ? n - 1 : i - 1;
                    break;
            }
            // Open the active menu.
            this.openActiveMenu();
        };
        /**
         * Handle the `changed` signal of a title object.
         */
        MenuBar.prototype._onTitleChanged = function () {
            this.update();
        };
        return MenuBar;
    }(exports.Widget));
    /**
     * The namespace for the `MenuBar` class statics.
     */
    (function (MenuBar) {
        /**
         * The default implementation of `IRenderer`.
         *
         * #### Notes
         * Subclasses are free to reimplement rendering methods as needed.
         */
        var Renderer = /** @class */ (function () {
            function Renderer() {
            }
            /**
             * Render the virtual element for a menu bar item.
             *
             * @param data - The data to use for rendering the item.
             *
             * @returns A virtual element representing the item.
             */
            Renderer.prototype.renderItem = function (data) {
                var className = this.createItemClass(data);
                var dataset = this.createItemDataset(data);
                var aria = this.createItemARIA(data);
                return virtualdom.h.li(__assign({ className: className, dataset: dataset, tabindex: '0', onfocus: data.onfocus }, aria), this.renderIcon(data), this.renderLabel(data));
            };
            /**
             * Render the icon element for a menu bar item.
             *
             * @param data - The data to use for rendering the icon.
             *
             * @returns A virtual element representing the item icon.
             */
            Renderer.prototype.renderIcon = function (data) {
                var className = this.createIconClass(data);
                /* <DEPRECATED> */
                if (typeof data.title.icon === 'string') {
                    return virtualdom.h.div({ className: className }, data.title.iconLabel);
                }
                /* </DEPRECATED> */
                // if data.title.icon is undefined, it will be ignored
                return virtualdom.h.div({ className: className }, data.title.icon, data.title.iconLabel);
            };
            /**
             * Render the label element for a menu item.
             *
             * @param data - The data to use for rendering the label.
             *
             * @returns A virtual element representing the item label.
             */
            Renderer.prototype.renderLabel = function (data) {
                var content = this.formatLabel(data);
                return virtualdom.h.div({
                    className: 'lm-MenuBar-itemLabel' +
                        /* <DEPRECATED> */
                        ' p-MenuBar-itemLabel'
                    /* </DEPRECATED> */
                }, content);
            };
            /**
             * Create the class name for the menu bar item.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the menu item.
             */
            Renderer.prototype.createItemClass = function (data) {
                var name = 'lm-MenuBar-item';
                /* <DEPRECATED> */
                name += ' p-MenuBar-item';
                /* </DEPRECATED> */
                if (data.title.className) {
                    name += " " + data.title.className;
                }
                if (data.active) {
                    name += ' lm-mod-active';
                    /* <DEPRECATED> */
                    name += ' p-mod-active';
                    /* </DEPRECATED> */
                }
                return name;
            };
            /**
             * Create the dataset for a menu bar item.
             *
             * @param data - The data to use for the item.
             *
             * @returns The dataset for the menu bar item.
             */
            Renderer.prototype.createItemDataset = function (data) {
                return data.title.dataset;
            };
            /**
             * Create the aria attributes for menu bar item.
             *
             * @param data - The data to use for the aria attributes.
             *
             * @returns The aria attributes object for the item.
             */
            Renderer.prototype.createItemARIA = function (data) {
                return { role: 'menuitem', 'aria-haspopup': 'true' };
            };
            /**
             * Create the class name for the menu bar item icon.
             *
             * @param data - The data to use for the class name.
             *
             * @returns The full class name for the item icon.
             */
            Renderer.prototype.createIconClass = function (data) {
                var name = 'lm-MenuBar-itemIcon';
                /* <DEPRECATED> */
                name += ' p-MenuBar-itemIcon';
                /* </DEPRECATED> */
                var extra = data.title.iconClass;
                return extra ? name + " " + extra : name;
            };
            /**
             * Create the render content for the label node.
             *
             * @param data - The data to use for the label content.
             *
             * @returns The content to add to the label node.
             */
            Renderer.prototype.formatLabel = function (data) {
                // Fetch the label text and mnemonic index.
                var _a = data.title, label = _a.label, mnemonic = _a.mnemonic;
                // If the index is out of range, do not modify the label.
                if (mnemonic < 0 || mnemonic >= label.length) {
                    return label;
                }
                // Split the label into parts.
                var prefix = label.slice(0, mnemonic);
                var suffix = label.slice(mnemonic + 1);
                var char = label[mnemonic];
                // Wrap the mnemonic character in a span.
                var span = virtualdom.h.span({
                    className: 'lm-MenuBar-itemMnemonic' +
                        /* <DEPRECATED> */
                        ' p-MenuBar-itemMnemonic'
                    /* </DEPRECATED> */
                }, char);
                // Return the content parts.
                return [prefix, span, suffix];
            };
            return Renderer;
        }());
        MenuBar.Renderer = Renderer;
        /**
         * The default `Renderer` instance.
         */
        MenuBar.defaultRenderer = new Renderer();
    })(exports.MenuBar || (exports.MenuBar = {}));
    /**
     * The namespace for the module implementation details.
     */
    var Private$3;
    (function (Private) {
        /**
         * Create the DOM node for a menu bar.
         */
        function createNode() {
            var node = document.createElement('div');
            var content = document.createElement('ul');
            content.className = 'lm-MenuBar-content';
            /* <DEPRECATED> */
            content.classList.add('p-MenuBar-content');
            /* </DEPRECATED> */
            node.appendChild(content);
            content.setAttribute('role', 'menubar');
            node.tabIndex = 0;
            content.tabIndex = 0;
            return node;
        }
        Private.createNode = createNode;
        /**
         * Find the best matching mnemonic item.
         *
         * The search starts at the given index and wraps around.
         */
        function findMnemonic(menus, key, start) {
            // Setup the result variables.
            var index = -1;
            var auto = -1;
            var multiple = false;
            // Normalize the key to upper case.
            var upperKey = key.toUpperCase();
            // Search the items from the given start index.
            for (var i = 0, n = menus.length; i < n; ++i) {
                // Compute the wrapped index.
                var k = (i + start) % n;
                // Look up the menu title.
                var title = menus[k].title;
                // Ignore titles with an empty label.
                if (title.label.length === 0) {
                    continue;
                }
                // Look up the mnemonic index for the label.
                var mn = title.mnemonic;
                // Handle a valid mnemonic index.
                if (mn >= 0 && mn < title.label.length) {
                    if (title.label[mn].toUpperCase() === upperKey) {
                        if (index === -1) {
                            index = k;
                        }
                        else {
                            multiple = true;
                        }
                    }
                    continue;
                }
                // Finally, handle the auto index if possible.
                if (auto === -1 && title.label[0].toUpperCase() === upperKey) {
                    auto = k;
                }
            }
            // Return the search results.
            return { index: index, multiple: multiple, auto: auto };
        }
        Private.findMnemonic = findMnemonic;
    })(Private$3 || (Private$3 = {}));

    /**
     * A widget which implements a canonical scroll bar.
     */
    var ScrollBar = /** @class */ (function (_super) {
        __extends(ScrollBar, _super);
        /**
         * Construct a new scroll bar.
         *
         * @param options - The options for initializing the scroll bar.
         */
        function ScrollBar(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { node: Private$2.createNode() }) || this;
            /**
             * A timeout callback for repeating the mouse press.
             */
            _this._onRepeat = function () {
                // Clear the repeat timer id.
                _this._repeatTimer = -1;
                // Bail if the mouse has been released.
                if (!_this._pressData) {
                    return;
                }
                // Look up the part that was pressed.
                var part = _this._pressData.part;
                // Bail if the thumb was pressed.
                if (part === 'thumb') {
                    return;
                }
                // Schedule the timer for another repeat.
                _this._repeatTimer = window.setTimeout(_this._onRepeat, 20);
                // Get the current mouse position.
                var mouseX = _this._pressData.mouseX;
                var mouseY = _this._pressData.mouseY;
                // Handle a decrement button repeat.
                if (part === 'decrement') {
                    // Bail if the mouse is not over the button.
                    if (!domutils.ElementExt.hitTest(_this.decrementNode, mouseX, mouseY)) {
                        return;
                    }
                    // Emit the step requested signal.
                    _this._stepRequested.emit('decrement');
                    // Finished.
                    return;
                }
                // Handle an increment button repeat.
                if (part === 'increment') {
                    // Bail if the mouse is not over the button.
                    if (!domutils.ElementExt.hitTest(_this.incrementNode, mouseX, mouseY)) {
                        return;
                    }
                    // Emit the step requested signal.
                    _this._stepRequested.emit('increment');
                    // Finished.
                    return;
                }
                // Handle a track repeat.
                if (part === 'track') {
                    // Bail if the mouse is not over the track.
                    if (!domutils.ElementExt.hitTest(_this.trackNode, mouseX, mouseY)) {
                        return;
                    }
                    // Fetch the thumb node.
                    var thumbNode = _this.thumbNode;
                    // Bail if the mouse is over the thumb.
                    if (domutils.ElementExt.hitTest(thumbNode, mouseX, mouseY)) {
                        return;
                    }
                    // Fetch the client rect for the thumb.
                    var thumbRect = thumbNode.getBoundingClientRect();
                    // Determine the direction for the page request.
                    var dir = void 0;
                    if (_this._orientation === 'horizontal') {
                        dir = mouseX < thumbRect.left ? 'decrement' : 'increment';
                    }
                    else {
                        dir = mouseY < thumbRect.top ? 'decrement' : 'increment';
                    }
                    // Emit the page requested signal.
                    _this._pageRequested.emit(dir);
                    // Finished.
                    return;
                }
            };
            _this._value = 0;
            _this._page = 10;
            _this._maximum = 100;
            _this._repeatTimer = -1;
            _this._pressData = null;
            _this._thumbMoved = new signaling.Signal(_this);
            _this._stepRequested = new signaling.Signal(_this);
            _this._pageRequested = new signaling.Signal(_this);
            _this.addClass('lm-ScrollBar');
            /* <DEPRECATED> */
            _this.addClass('p-ScrollBar');
            /* </DEPRECATED> */
            _this.setFlag(exports.Widget.Flag.DisallowLayout);
            // Set the orientation.
            _this._orientation = options.orientation || 'vertical';
            _this.dataset['orientation'] = _this._orientation;
            // Parse the rest of the options.
            if (options.maximum !== undefined) {
                _this._maximum = Math.max(0, options.maximum);
            }
            if (options.page !== undefined) {
                _this._page = Math.max(0, options.page);
            }
            if (options.value !== undefined) {
                _this._value = Math.max(0, Math.min(options.value, _this._maximum));
            }
            return _this;
        }
        Object.defineProperty(ScrollBar.prototype, "thumbMoved", {
            /**
             * A signal emitted when the user moves the scroll thumb.
             *
             * #### Notes
             * The payload is the current value of the scroll bar.
             */
            get: function () {
                return this._thumbMoved;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "stepRequested", {
            /**
             * A signal emitted when the user clicks a step button.
             *
             * #### Notes
             * The payload is whether a decrease or increase is requested.
             */
            get: function () {
                return this._stepRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "pageRequested", {
            /**
             * A signal emitted when the user clicks the scroll track.
             *
             * #### Notes
             * The payload is whether a decrease or increase is requested.
             */
            get: function () {
                return this._pageRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "orientation", {
            /**
             * Get the orientation of the scroll bar.
             */
            get: function () {
                return this._orientation;
            },
            /**
             * Set the orientation of the scroll bar.
             */
            set: function (value) {
                // Do nothing if the orientation does not change.
                if (this._orientation === value) {
                    return;
                }
                // Release the mouse before making changes.
                this._releaseMouse();
                // Update the internal orientation.
                this._orientation = value;
                this.dataset['orientation'] = value;
                // Schedule an update the scroll bar.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "value", {
            /**
             * Get the current value of the scroll bar.
             */
            get: function () {
                return this._value;
            },
            /**
             * Set the current value of the scroll bar.
             *
             * #### Notes
             * The value will be clamped to the range `[0, maximum]`.
             */
            set: function (value) {
                // Clamp the value to the allowable range.
                value = Math.max(0, Math.min(value, this._maximum));
                // Do nothing if the value does not change.
                if (this._value === value) {
                    return;
                }
                // Update the internal value.
                this._value = value;
                // Schedule an update the scroll bar.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "page", {
            /**
             * Get the page size of the scroll bar.
             *
             * #### Notes
             * The page size is the amount of visible content in the scrolled
             * region, expressed in data units. It determines the size of the
             * scroll bar thumb.
             */
            get: function () {
                return this._page;
            },
            /**
             * Set the page size of the scroll bar.
             *
             * #### Notes
             * The page size will be clamped to the range `[0, Infinity]`.
             */
            set: function (value) {
                // Clamp the page size to the allowable range.
                value = Math.max(0, value);
                // Do nothing if the value does not change.
                if (this._page === value) {
                    return;
                }
                // Update the internal page size.
                this._page = value;
                // Schedule an update the scroll bar.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "maximum", {
            /**
             * Get the maximum value of the scroll bar.
             */
            get: function () {
                return this._maximum;
            },
            /**
             * Set the maximum value of the scroll bar.
             *
             * #### Notes
             * The max size will be clamped to the range `[0, Infinity]`.
             */
            set: function (value) {
                // Clamp the value to the allowable range.
                value = Math.max(0, value);
                // Do nothing if the value does not change.
                if (this._maximum === value) {
                    return;
                }
                // Update the internal values.
                this._maximum = value;
                // Clamp the current value to the new range.
                this._value = Math.min(this._value, value);
                // Schedule an update the scroll bar.
                this.update();
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "decrementNode", {
            /**
             * The scroll bar decrement button node.
             *
             * #### Notes
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-ScrollBar-button')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "incrementNode", {
            /**
             * The scroll bar increment button node.
             *
             * #### Notes
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-ScrollBar-button')[1];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "trackNode", {
            /**
             * The scroll bar track node.
             *
             * #### Notes
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-ScrollBar-track')[0];
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(ScrollBar.prototype, "thumbNode", {
            /**
             * The scroll bar thumb node.
             *
             * #### Notes
             * Modifying this node directly can lead to undefined behavior.
             */
            get: function () {
                return this.node.getElementsByClassName('lm-ScrollBar-thumb')[0];
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Handle the DOM events for the scroll bar.
         *
         * @param event - The DOM event sent to the scroll bar.
         *
         * #### Notes
         * This method implements the DOM `EventListener` interface and is
         * called in response to events on the scroll bar's DOM node.
         *
         * This should not be called directly by user code.
         */
        ScrollBar.prototype.handleEvent = function (event) {
            switch (event.type) {
                case 'mousedown':
                    this._evtMouseDown(event);
                    break;
                case 'mousemove':
                    this._evtMouseMove(event);
                    break;
                case 'mouseup':
                    this._evtMouseUp(event);
                    break;
                case 'keydown':
                    this._evtKeyDown(event);
                    break;
                case 'contextmenu':
                    event.preventDefault();
                    event.stopPropagation();
                    break;
            }
        };
        /**
         * A method invoked on a 'before-attach' message.
         */
        ScrollBar.prototype.onBeforeAttach = function (msg) {
            this.node.addEventListener('mousedown', this);
            this.update();
        };
        /**
         * A method invoked on an 'after-detach' message.
         */
        ScrollBar.prototype.onAfterDetach = function (msg) {
            this.node.removeEventListener('mousedown', this);
            this._releaseMouse();
        };
        /**
         * A method invoked on an 'update-request' message.
         */
        ScrollBar.prototype.onUpdateRequest = function (msg) {
            // Convert the value and page into percentages.
            var value = (this._value * 100) / this._maximum;
            var page = (this._page * 100) / (this._page + this._maximum);
            // Clamp the value and page to the relevant range.
            value = Math.max(0, Math.min(value, 100));
            page = Math.max(0, Math.min(page, 100));
            // Fetch the thumb style.
            var thumbStyle = this.thumbNode.style;
            // Update the thumb style for the current orientation.
            if (this._orientation === 'horizontal') {
                thumbStyle.top = '';
                thumbStyle.height = '';
                thumbStyle.left = value + "%";
                thumbStyle.width = page + "%";
                thumbStyle.transform = "translate(" + -value + "%, 0%)";
            }
            else {
                thumbStyle.left = '';
                thumbStyle.width = '';
                thumbStyle.top = value + "%";
                thumbStyle.height = page + "%";
                thumbStyle.transform = "translate(0%, " + -value + "%)";
            }
        };
        /**
         * Handle the `'keydown'` event for the scroll bar.
         */
        ScrollBar.prototype._evtKeyDown = function (event) {
            // Stop all input events during drag.
            event.preventDefault();
            event.stopPropagation();
            // Ignore anything except the `Escape` key.
            if (event.keyCode !== 27) {
                return;
            }
            // Fetch the previous scroll value.
            var value = this._pressData ? this._pressData.value : -1;
            // Release the mouse.
            this._releaseMouse();
            // Restore the old scroll value if possible.
            if (value !== -1) {
                this._moveThumb(value);
            }
        };
        /**
         * Handle the `'mousedown'` event for the scroll bar.
         */
        ScrollBar.prototype._evtMouseDown = function (event) {
            // Do nothing if it's not a left mouse press.
            if (event.button !== 0) {
                return;
            }
            // Send an activate request to the scroll bar. This can be
            // used by message hooks to activate something relevant.
            this.activate();
            // Do nothing if the mouse is already captured.
            if (this._pressData) {
                return;
            }
            // Find the pressed scroll bar part.
            var part = Private$2.findPart(this, event.target);
            // Do nothing if the part is not of interest.
            if (!part) {
                return;
            }
            // Stop the event propagation.
            event.preventDefault();
            event.stopPropagation();
            // Override the mouse cursor.
            var override = dragdrop.Drag.overrideCursor('default');
            // Set up the press data.
            this._pressData = {
                part: part,
                override: override,
                delta: -1,
                value: -1,
                mouseX: event.clientX,
                mouseY: event.clientY
            };
            // Add the extra event listeners.
            document.addEventListener('mousemove', this, true);
            document.addEventListener('mouseup', this, true);
            document.addEventListener('keydown', this, true);
            document.addEventListener('contextmenu', this, true);
            // Handle a thumb press.
            if (part === 'thumb') {
                // Fetch the thumb node.
                var thumbNode = this.thumbNode;
                // Fetch the client rect for the thumb.
                var thumbRect = thumbNode.getBoundingClientRect();
                // Update the press data delta for the current orientation.
                if (this._orientation === 'horizontal') {
                    this._pressData.delta = event.clientX - thumbRect.left;
                }
                else {
                    this._pressData.delta = event.clientY - thumbRect.top;
                }
                // Add the active class to the thumb node.
                thumbNode.classList.add('lm-mod-active');
                /* <DEPRECATED> */
                thumbNode.classList.add('p-mod-active');
                /* </DEPRECATED> */
                // Store the current value in the press data.
                this._pressData.value = this._value;
                // Finished.
                return;
            }
            // Handle a track press.
            if (part === 'track') {
                // Fetch the client rect for the thumb.
                var thumbRect = this.thumbNode.getBoundingClientRect();
                // Determine the direction for the page request.
                var dir = void 0;
                if (this._orientation === 'horizontal') {
                    dir = event.clientX < thumbRect.left ? 'decrement' : 'increment';
                }
                else {
                    dir = event.clientY < thumbRect.top ? 'decrement' : 'increment';
                }
                // Start the repeat timer.
                this._repeatTimer = window.setTimeout(this._onRepeat, 350);
                // Emit the page requested signal.
                this._pageRequested.emit(dir);
                // Finished.
                return;
            }
            // Handle a decrement button press.
            if (part === 'decrement') {
                // Add the active class to the decrement node.
                this.decrementNode.classList.add('lm-mod-active');
                /* <DEPRECATED> */
                this.decrementNode.classList.add('p-mod-active');
                /* </DEPRECATED> */
                // Start the repeat timer.
                this._repeatTimer = window.setTimeout(this._onRepeat, 350);
                // Emit the step requested signal.
                this._stepRequested.emit('decrement');
                // Finished.
                return;
            }
            // Handle an increment button press.
            if (part === 'increment') {
                // Add the active class to the increment node.
                this.incrementNode.classList.add('lm-mod-active');
                /* <DEPRECATED> */
                this.incrementNode.classList.add('p-mod-active');
                /* </DEPRECATED> */
                // Start the repeat timer.
                this._repeatTimer = window.setTimeout(this._onRepeat, 350);
                // Emit the step requested signal.
                this._stepRequested.emit('increment');
                // Finished.
                return;
            }
        };
        /**
         * Handle the `'mousemove'` event for the scroll bar.
         */
        ScrollBar.prototype._evtMouseMove = function (event) {
            // Do nothing if no drag is in progress.
            if (!this._pressData) {
                return;
            }
            // Stop the event propagation.
            event.preventDefault();
            event.stopPropagation();
            // Update the mouse position.
            this._pressData.mouseX = event.clientX;
            this._pressData.mouseY = event.clientY;
            // Bail if the thumb is not being dragged.
            if (this._pressData.part !== 'thumb') {
                return;
            }
            // Get the client rect for the thumb and track.
            var thumbRect = this.thumbNode.getBoundingClientRect();
            var trackRect = this.trackNode.getBoundingClientRect();
            // Fetch the scroll geometry based on the orientation.
            var trackPos;
            var trackSpan;
            if (this._orientation === 'horizontal') {
                trackPos = event.clientX - trackRect.left - this._pressData.delta;
                trackSpan = trackRect.width - thumbRect.width;
            }
            else {
                trackPos = event.clientY - trackRect.top - this._pressData.delta;
                trackSpan = trackRect.height - thumbRect.height;
            }
            // Compute the desired value from the scroll geometry.
            var value = trackSpan === 0 ? 0 : (trackPos * this._maximum) / trackSpan;
            // Move the thumb to the computed value.
            this._moveThumb(value);
        };
        /**
         * Handle the `'mouseup'` event for the scroll bar.
         */
        ScrollBar.prototype._evtMouseUp = function (event) {
            // Do nothing if it's not a left mouse release.
            if (event.button !== 0) {
                return;
            }
            // Stop the event propagation.
            event.preventDefault();
            event.stopPropagation();
            // Release the mouse.
            this._releaseMouse();
        };
        /**
         * Release the mouse and restore the node states.
         */
        ScrollBar.prototype._releaseMouse = function () {
            // Bail if there is no press data.
            if (!this._pressData) {
                return;
            }
            // Clear the repeat timer.
            clearTimeout(this._repeatTimer);
            this._repeatTimer = -1;
            // Clear the press data.
            this._pressData.override.dispose();
            this._pressData = null;
            // Remove the extra event listeners.
            document.removeEventListener('mousemove', this, true);
            document.removeEventListener('mouseup', this, true);
            document.removeEventListener('keydown', this, true);
            document.removeEventListener('contextmenu', this, true);
            // Remove the active classes from the nodes.
            this.thumbNode.classList.remove('lm-mod-active');
            this.decrementNode.classList.remove('lm-mod-active');
            this.incrementNode.classList.remove('lm-mod-active');
            /* <DEPRECATED> */
            this.thumbNode.classList.remove('p-mod-active');
            this.decrementNode.classList.remove('p-mod-active');
            this.incrementNode.classList.remove('p-mod-active');
            /* </DEPRECATED> */
        };
        /**
         * Move the thumb to the specified position.
         */
        ScrollBar.prototype._moveThumb = function (value) {
            // Clamp the value to the allowed range.
            value = Math.max(0, Math.min(value, this._maximum));
            // Bail if the value does not change.
            if (this._value === value) {
                return;
            }
            // Update the internal value.
            this._value = value;
            // Schedule an update of the scroll bar.
            this.update();
            // Emit the thumb moved signal.
            this._thumbMoved.emit(value);
        };
        return ScrollBar;
    }(exports.Widget));
    /**
     * The namespace for the module implementation details.
     */
    var Private$2;
    (function (Private) {
        /**
         * Create the DOM node for a scroll bar.
         */
        function createNode() {
            var node = document.createElement('div');
            var decrement = document.createElement('div');
            var increment = document.createElement('div');
            var track = document.createElement('div');
            var thumb = document.createElement('div');
            decrement.className = 'lm-ScrollBar-button';
            increment.className = 'lm-ScrollBar-button';
            decrement.dataset['action'] = 'decrement';
            increment.dataset['action'] = 'increment';
            track.className = 'lm-ScrollBar-track';
            thumb.className = 'lm-ScrollBar-thumb';
            /* <DEPRECATED> */
            decrement.classList.add('p-ScrollBar-button');
            increment.classList.add('p-ScrollBar-button');
            track.classList.add('p-ScrollBar-track');
            thumb.classList.add('p-ScrollBar-thumb');
            /* </DEPRECATED> */
            track.appendChild(thumb);
            node.appendChild(decrement);
            node.appendChild(track);
            node.appendChild(increment);
            return node;
        }
        Private.createNode = createNode;
        /**
         * Find the scroll bar part which contains the given target.
         */
        function findPart(scrollBar, target) {
            // Test the thumb.
            if (scrollBar.thumbNode.contains(target)) {
                return 'thumb';
            }
            // Test the track.
            if (scrollBar.trackNode.contains(target)) {
                return 'track';
            }
            // Test the decrement button.
            if (scrollBar.decrementNode.contains(target)) {
                return 'decrement';
            }
            // Test the increment button.
            if (scrollBar.incrementNode.contains(target)) {
                return 'increment';
            }
            // Indicate no match.
            return null;
        }
        Private.findPart = findPart;
    })(Private$2 || (Private$2 = {}));

    /**
     * A concrete layout implementation which holds a single widget.
     *
     * #### Notes
     * This class is useful for creating simple container widgets which
     * hold a single child. The child should be positioned with CSS.
     */
    var SingletonLayout = /** @class */ (function (_super) {
        __extends(SingletonLayout, _super);
        function SingletonLayout() {
            var _this = _super !== null && _super.apply(this, arguments) || this;
            _this._widget = null;
            return _this;
        }
        /**
         * Dispose of the resources held by the layout.
         */
        SingletonLayout.prototype.dispose = function () {
            if (this._widget) {
                var widget = this._widget;
                this._widget = null;
                widget.dispose();
            }
            _super.prototype.dispose.call(this);
        };
        Object.defineProperty(SingletonLayout.prototype, "widget", {
            /**
             * Get the child widget for the layout.
             */
            get: function () {
                return this._widget;
            },
            /**
             * Set the child widget for the layout.
             *
             * #### Notes
             * Setting the child widget will cause the old child widget to be
             * automatically disposed. If that is not desired, set the parent
             * of the old child to `null` before assigning a new child.
             */
            set: function (widget) {
                // Remove the widget from its current parent. This is a no-op
                // if the widget's parent is already the layout parent widget.
                if (widget) {
                    widget.parent = this.parent;
                }
                // Bail early if the widget does not change.
                if (this._widget === widget) {
                    return;
                }
                // Dispose of the old child widget.
                if (this._widget) {
                    this._widget.dispose();
                }
                // Update the internal widget.
                this._widget = widget;
                // Attach the new child widget if needed.
                if (this.parent && widget) {
                    this.attachWidget(widget);
                }
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Create an iterator over the widgets in the layout.
         *
         * @returns A new iterator over the widgets in the layout.
         */
        SingletonLayout.prototype.iter = function () {
            return this._widget ? algorithm.once(this._widget) : algorithm.empty();
        };
        /**
         * Remove a widget from the layout.
         *
         * @param widget - The widget to remove from the layout.
         *
         * #### Notes
         * A widget is automatically removed from the layout when its `parent`
         * is set to `null`. This method should only be invoked directly when
         * removing a widget from a layout which has yet to be installed on a
         * parent widget.
         *
         * This method does *not* modify the widget's `parent`.
         */
        SingletonLayout.prototype.removeWidget = function (widget) {
            // Bail early if the widget does not exist in the layout.
            if (this._widget !== widget) {
                return;
            }
            // Clear the internal widget.
            this._widget = null;
            // If the layout is parented, detach the widget from the DOM.
            if (this.parent) {
                this.detachWidget(widget);
            }
        };
        /**
         * Perform layout initialization which requires the parent widget.
         */
        SingletonLayout.prototype.init = function () {
            var _this = this;
            _super.prototype.init.call(this);
            algorithm.each(this, function (widget) {
                _this.attachWidget(widget);
            });
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This method is called automatically by the single layout at the
         * appropriate time. It should not be called directly by user code.
         *
         * The default implementation adds the widgets's node to the parent's
         * node at the proper location, and sends the appropriate attach
         * messages to the widget if the parent is attached to the DOM.
         *
         * Subclasses may reimplement this method to control how the widget's
         * node is added to the parent's node.
         */
        SingletonLayout.prototype.attachWidget = function (widget) {
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget's node to the parent.
            this.parent.node.appendChild(widget.node);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This method is called automatically by the single layout at the
         * appropriate time. It should not be called directly by user code.
         *
         * The default implementation removes the widget's node from the
         * parent's node, and sends the appropriate detach messages to the
         * widget if the parent is attached to the DOM.
         *
         * Subclasses may reimplement this method to control how the widget's
         * node is removed from the parent's node.
         */
        SingletonLayout.prototype.detachWidget = function (widget) {
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
        };
        return SingletonLayout;
    }(exports.Layout));

    /**
     * A layout where visible widgets are stacked atop one another.
     *
     * #### Notes
     * The Z-order of the visible widgets follows their layout order.
     */
    var StackedLayout = /** @class */ (function (_super) {
        __extends(StackedLayout, _super);
        function StackedLayout(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, options) || this;
            _this._dirty = false;
            _this._items = [];
            _this._box = null;
            _this._hiddenMode =
                options.hiddenMode !== undefined
                    ? options.hiddenMode
                    : exports.Widget.HiddenMode.Display;
            return _this;
        }
        Object.defineProperty(StackedLayout.prototype, "hiddenMode", {
            /**
             * The method for hiding widgets.
             *
             * #### Notes
             * If there is only one child widget, `Display` hiding mode will be used
             * regardless of this setting.
             */
            get: function () {
                return this._hiddenMode;
            },
            /**
             * Set the method for hiding widgets.
             *
             * #### Notes
             * If there is only one child widget, `Display` hiding mode will be used
             * regardless of this setting.
             */
            set: function (v) {
                var _this = this;
                if (this._hiddenMode === v) {
                    return;
                }
                this._hiddenMode = v;
                if (this.widgets.length > 1) {
                    this.widgets.forEach(function (w) {
                        w.hiddenMode = _this._hiddenMode;
                    });
                }
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Dispose of the resources held by the layout.
         */
        StackedLayout.prototype.dispose = function () {
            // Dispose of the layout items.
            algorithm.each(this._items, function (item) {
                item.dispose();
            });
            // Clear the layout state.
            this._box = null;
            this._items.length = 0;
            // Dispose of the rest of the layout.
            _super.prototype.dispose.call(this);
        };
        /**
         * Attach a widget to the parent's DOM node.
         *
         * @param index - The current index of the widget in the layout.
         *
         * @param widget - The widget to attach to the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        StackedLayout.prototype.attachWidget = function (index, widget) {
            // Using transform create an additional layer in the pixel pipeline
            // to limit the number of layer, it is set only if there is more than one widget.
            if (this._hiddenMode === exports.Widget.HiddenMode.Scale &&
                this._items.length > 0) {
                if (this._items.length === 1) {
                    this.widgets[0].hiddenMode = exports.Widget.HiddenMode.Scale;
                }
                widget.hiddenMode = exports.Widget.HiddenMode.Scale;
            }
            else {
                widget.hiddenMode = exports.Widget.HiddenMode.Display;
            }
            // Create and add a new layout item for the widget.
            algorithm.ArrayExt.insert(this._items, index, new LayoutItem(widget));
            // Send a `'before-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeAttach);
            }
            // Add the widget's node to the parent.
            this.parent.node.appendChild(widget.node);
            // Send an `'after-attach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterAttach);
            }
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * Move a widget in the parent's DOM node.
         *
         * @param fromIndex - The previous index of the widget in the layout.
         *
         * @param toIndex - The current index of the widget in the layout.
         *
         * @param widget - The widget to move in the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        StackedLayout.prototype.moveWidget = function (fromIndex, toIndex, widget) {
            // Move the layout item for the widget.
            algorithm.ArrayExt.move(this._items, fromIndex, toIndex);
            // Post an update request for the parent widget.
            this.parent.update();
        };
        /**
         * Detach a widget from the parent's DOM node.
         *
         * @param index - The previous index of the widget in the layout.
         *
         * @param widget - The widget to detach from the parent.
         *
         * #### Notes
         * This is a reimplementation of the superclass method.
         */
        StackedLayout.prototype.detachWidget = function (index, widget) {
            // Remove the layout item for the widget.
            var item = algorithm.ArrayExt.removeAt(this._items, index);
            // Send a `'before-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.BeforeDetach);
            }
            // Remove the widget's node from the parent.
            this.parent.node.removeChild(widget.node);
            // Send an `'after-detach'` message if the parent is attached.
            if (this.parent.isAttached) {
                messaging.MessageLoop.sendMessage(widget, exports.Widget.Msg.AfterDetach);
            }
            // Reset the z-index for the widget.
            item.widget.node.style.zIndex = '';
            // Reset the hidden mode for the widget.
            if (this._hiddenMode === exports.Widget.HiddenMode.Scale) {
                widget.hiddenMode = exports.Widget.HiddenMode.Display;
                // Reset the hidden mode for the first widget if necessary.
                if (this._items.length === 1) {
                    this._items[0].widget.hiddenMode = exports.Widget.HiddenMode.Display;
                }
            }
            // Dispose of the layout item.
            item.dispose();
            // Post a fit request for the parent widget.
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'before-show'` message.
         */
        StackedLayout.prototype.onBeforeShow = function (msg) {
            _super.prototype.onBeforeShow.call(this, msg);
            this.parent.update();
        };
        /**
         * A message handler invoked on a `'before-attach'` message.
         */
        StackedLayout.prototype.onBeforeAttach = function (msg) {
            _super.prototype.onBeforeAttach.call(this, msg);
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-shown'` message.
         */
        StackedLayout.prototype.onChildShown = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'child-hidden'` message.
         */
        StackedLayout.prototype.onChildHidden = function (msg) {
            this.parent.fit();
        };
        /**
         * A message handler invoked on a `'resize'` message.
         */
        StackedLayout.prototype.onResize = function (msg) {
            if (this.parent.isVisible) {
                this._update(msg.width, msg.height);
            }
        };
        /**
         * A message handler invoked on an `'update-request'` message.
         */
        StackedLayout.prototype.onUpdateRequest = function (msg) {
            if (this.parent.isVisible) {
                this._update(-1, -1);
            }
        };
        /**
         * A message handler invoked on a `'fit-request'` message.
         */
        StackedLayout.prototype.onFitRequest = function (msg) {
            if (this.parent.isAttached) {
                this._fit();
            }
        };
        /**
         * Fit the layout to the total size required by the widgets.
         */
        StackedLayout.prototype._fit = function () {
            // Set up the computed minimum size.
            var minW = 0;
            var minH = 0;
            // Update the computed minimum size.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item.
                var item = this._items[i];
                // Ignore hidden items.
                if (item.isHidden) {
                    continue;
                }
                // Update the size limits for the item.
                item.fit();
                // Update the computed minimum size.
                minW = Math.max(minW, item.minWidth);
                minH = Math.max(minH, item.minHeight);
            }
            // Update the box sizing and add it to the computed min size.
            var box = (this._box = domutils.ElementExt.boxSizing(this.parent.node));
            minW += box.horizontalSum;
            minH += box.verticalSum;
            // Update the parent's min size constraints.
            var style = this.parent.node.style;
            style.minWidth = minW + "px";
            style.minHeight = minH + "px";
            // Set the dirty flag to ensure only a single update occurs.
            this._dirty = true;
            // Notify the ancestor that it should fit immediately. This may
            // cause a resize of the parent, fulfilling the required update.
            if (this.parent.parent) {
                messaging.MessageLoop.sendMessage(this.parent.parent, exports.Widget.Msg.FitRequest);
            }
            // If the dirty flag is still set, the parent was not resized.
            // Trigger the required update on the parent widget immediately.
            if (this._dirty) {
                messaging.MessageLoop.sendMessage(this.parent, exports.Widget.Msg.UpdateRequest);
            }
        };
        /**
         * Update the layout position and size of the widgets.
         *
         * The parent offset dimensions should be `-1` if unknown.
         */
        StackedLayout.prototype._update = function (offsetWidth, offsetHeight) {
            // Clear the dirty flag to indicate the update occurred.
            this._dirty = false;
            // Compute the visible item count.
            var nVisible = 0;
            for (var i = 0, n = this._items.length; i < n; ++i) {
                nVisible += +!this._items[i].isHidden;
            }
            // Bail early if there are no visible items to layout.
            if (nVisible === 0) {
                return;
            }
            // Measure the parent if the offset dimensions are unknown.
            if (offsetWidth < 0) {
                offsetWidth = this.parent.node.offsetWidth;
            }
            if (offsetHeight < 0) {
                offsetHeight = this.parent.node.offsetHeight;
            }
            // Ensure the parent box sizing data is computed.
            if (!this._box) {
                this._box = domutils.ElementExt.boxSizing(this.parent.node);
            }
            // Compute the actual layout bounds adjusted for border and padding.
            var top = this._box.paddingTop;
            var left = this._box.paddingLeft;
            var width = offsetWidth - this._box.horizontalSum;
            var height = offsetHeight - this._box.verticalSum;
            // Update the widget stacking order and layout geometry.
            for (var i = 0, n = this._items.length; i < n; ++i) {
                // Fetch the item.
                var item = this._items[i];
                // Ignore hidden items.
                if (item.isHidden) {
                    continue;
                }
                // Set the z-index for the widget.
                item.widget.node.style.zIndex = "" + i;
                // Update the item geometry.
                item.update(left, top, width, height);
            }
        };
        return StackedLayout;
    }(PanelLayout));

    /**
     * A panel where visible widgets are stacked atop one another.
     *
     * #### Notes
     * This class provides a convenience wrapper around a [[StackedLayout]].
     */
    var StackedPanel = /** @class */ (function (_super) {
        __extends(StackedPanel, _super);
        /**
         * Construct a new stacked panel.
         *
         * @param options - The options for initializing the panel.
         */
        function StackedPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this, { layout: Private$1.createLayout(options) }) || this;
            _this._widgetRemoved = new signaling.Signal(_this);
            _this.addClass('lm-StackedPanel');
            /* <DEPRECATED> */
            _this.addClass('p-StackedPanel');
            return _this;
            /* </DEPRECATED> */
        }
        Object.defineProperty(StackedPanel.prototype, "hiddenMode", {
            /**
             * The method for hiding widgets.
             *
             * #### Notes
             * If there is only one child widget, `Display` hiding mode will be used
             * regardless of this setting.
             */
            get: function () {
                return this.layout.hiddenMode;
            },
            /**
             * Set the method for hiding widgets.
             *
             * #### Notes
             * If there is only one child widget, `Display` hiding mode will be used
             * regardless of this setting.
             */
            set: function (v) {
                this.layout.hiddenMode = v;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(StackedPanel.prototype, "widgetRemoved", {
            /**
             * A signal emitted when a widget is removed from a stacked panel.
             */
            get: function () {
                return this._widgetRemoved;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * A message handler invoked on a `'child-added'` message.
         */
        StackedPanel.prototype.onChildAdded = function (msg) {
            msg.child.addClass('lm-StackedPanel-child');
            /* <DEPRECATED> */
            msg.child.addClass('p-StackedPanel-child');
            /* </DEPRECATED> */
        };
        /**
         * A message handler invoked on a `'child-removed'` message.
         */
        StackedPanel.prototype.onChildRemoved = function (msg) {
            msg.child.removeClass('lm-StackedPanel-child');
            /* <DEPRECATED> */
            msg.child.removeClass('p-StackedPanel-child');
            /* </DEPRECATED> */
            this._widgetRemoved.emit(msg.child);
        };
        return StackedPanel;
    }(Panel));
    /**
     * The namespace for the module implementation details.
     */
    var Private$1;
    (function (Private) {
        /**
         * Create a stacked layout for the given panel options.
         */
        function createLayout(options) {
            return options.layout || new StackedLayout();
        }
        Private.createLayout = createLayout;
    })(Private$1 || (Private$1 = {}));

    /**
     * A widget which combines a `TabBar` and a `StackedPanel`.
     *
     * #### Notes
     * This is a simple panel which handles the common case of a tab bar
     * placed next to a content area. The selected tab controls the widget
     * which is shown in the content area.
     *
     * For use cases which require more control than is provided by this
     * panel, the `TabBar` widget may be used independently.
     */
    var TabPanel = /** @class */ (function (_super) {
        __extends(TabPanel, _super);
        /**
         * Construct a new tab panel.
         *
         * @param options - The options for initializing the tab panel.
         */
        function TabPanel(options) {
            if (options === void 0) { options = {}; }
            var _this = _super.call(this) || this;
            _this._currentChanged = new signaling.Signal(_this);
            _this._addRequested = new signaling.Signal(_this);
            _this.addClass('lm-TabPanel');
            /* <DEPRECATED> */
            _this.addClass('p-TabPanel');
            /* </DEPRECATED> */
            // Create the tab bar and stacked panel.
            _this.tabBar = new exports.TabBar(options);
            _this.tabBar.addClass('lm-TabPanel-tabBar');
            _this.stackedPanel = new StackedPanel();
            _this.stackedPanel.addClass('lm-TabPanel-stackedPanel');
            /* <DEPRECATED> */
            _this.tabBar.addClass('p-TabPanel-tabBar');
            _this.stackedPanel.addClass('p-TabPanel-stackedPanel');
            /* </DEPRECATED> */
            // Connect the tab bar signal handlers.
            _this.tabBar.tabMoved.connect(_this._onTabMoved, _this);
            _this.tabBar.currentChanged.connect(_this._onCurrentChanged, _this);
            _this.tabBar.tabCloseRequested.connect(_this._onTabCloseRequested, _this);
            _this.tabBar.tabActivateRequested.connect(_this._onTabActivateRequested, _this);
            _this.tabBar.addRequested.connect(_this._onTabAddRequested, _this);
            // Connect the stacked panel signal handlers.
            _this.stackedPanel.widgetRemoved.connect(_this._onWidgetRemoved, _this);
            // Get the data related to the placement.
            _this._tabPlacement = options.tabPlacement || 'top';
            var direction = Private.directionFromPlacement(_this._tabPlacement);
            var orientation = Private.orientationFromPlacement(_this._tabPlacement);
            // Configure the tab bar for the placement.
            _this.tabBar.orientation = orientation;
            _this.tabBar.dataset['placement'] = _this._tabPlacement;
            // Create the box layout.
            var layout = new exports.BoxLayout({ direction: direction, spacing: 0 });
            // Set the stretch factors for the child widgets.
            exports.BoxLayout.setStretch(_this.tabBar, 0);
            exports.BoxLayout.setStretch(_this.stackedPanel, 1);
            // Add the child widgets to the layout.
            layout.addWidget(_this.tabBar);
            layout.addWidget(_this.stackedPanel);
            // Install the layout on the tab panel.
            _this.layout = layout;
            return _this;
        }
        Object.defineProperty(TabPanel.prototype, "currentChanged", {
            /**
             * A signal emitted when the current tab is changed.
             *
             * #### Notes
             * This signal is emitted when the currently selected tab is changed
             * either through user or programmatic interaction.
             *
             * Notably, this signal is not emitted when the index of the current
             * tab changes due to tabs being inserted, removed, or moved. It is
             * only emitted when the actual current tab node is changed.
             */
            get: function () {
                return this._currentChanged;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "currentIndex", {
            /**
             * Get the index of the currently selected tab.
             *
             * #### Notes
             * This will be `-1` if no tab is selected.
             */
            get: function () {
                return this.tabBar.currentIndex;
            },
            /**
             * Set the index of the currently selected tab.
             *
             * #### Notes
             * If the index is out of range, it will be set to `-1`.
             */
            set: function (value) {
                this.tabBar.currentIndex = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "currentWidget", {
            /**
             * Get the currently selected widget.
             *
             * #### Notes
             * This will be `null` if there is no selected tab.
             */
            get: function () {
                var title = this.tabBar.currentTitle;
                return title ? title.owner : null;
            },
            /**
             * Set the currently selected widget.
             *
             * #### Notes
             * If the widget is not in the panel, it will be set to `null`.
             */
            set: function (value) {
                this.tabBar.currentTitle = value ? value.title : null;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "tabsMovable", {
            /**
             * Get the whether the tabs are movable by the user.
             *
             * #### Notes
             * Tabs can always be moved programmatically.
             */
            get: function () {
                return this.tabBar.tabsMovable;
            },
            /**
             * Set the whether the tabs are movable by the user.
             *
             * #### Notes
             * Tabs can always be moved programmatically.
             */
            set: function (value) {
                this.tabBar.tabsMovable = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "addButtonEnabled", {
            /**
             * Get the whether the add button is enabled.
             *
             */
            get: function () {
                return this.tabBar.addButtonEnabled;
            },
            /**
             * Set the whether the add button is enabled.
             *
             */
            set: function (value) {
                this.tabBar.addButtonEnabled = value;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "tabPlacement", {
            /**
             * Get the tab placement for the tab panel.
             *
             * #### Notes
             * This controls the position of the tab bar relative to the content.
             */
            get: function () {
                return this._tabPlacement;
            },
            /**
             * Set the tab placement for the tab panel.
             *
             * #### Notes
             * This controls the position of the tab bar relative to the content.
             */
            set: function (value) {
                // Bail if the placement does not change.
                if (this._tabPlacement === value) {
                    return;
                }
                // Update the internal value.
                this._tabPlacement = value;
                // Get the values related to the placement.
                var direction = Private.directionFromPlacement(value);
                var orientation = Private.orientationFromPlacement(value);
                // Configure the tab bar for the placement.
                this.tabBar.orientation = orientation;
                this.tabBar.dataset['placement'] = value;
                // Update the layout direction.
                this.layout.direction = direction;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "addRequested", {
            /**
             * A signal emitted when the add button on a tab bar is clicked.
             *
             */
            get: function () {
                return this._addRequested;
            },
            enumerable: true,
            configurable: true
        });
        Object.defineProperty(TabPanel.prototype, "widgets", {
            /**
             * A read-only array of the widgets in the panel.
             */
            get: function () {
                return this.stackedPanel.widgets;
            },
            enumerable: true,
            configurable: true
        });
        /**
         * Add a widget to the end of the tab panel.
         *
         * @param widget - The widget to add to the tab panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         *
         * The widget's `title` is used to populate the tab.
         */
        TabPanel.prototype.addWidget = function (widget) {
            this.insertWidget(this.widgets.length, widget);
        };
        /**
         * Insert a widget into the tab panel at a specified index.
         *
         * @param index - The index at which to insert the widget.
         *
         * @param widget - The widget to insert into to the tab panel.
         *
         * #### Notes
         * If the widget is already contained in the panel, it will be moved.
         *
         * The widget's `title` is used to populate the tab.
         */
        TabPanel.prototype.insertWidget = function (index, widget) {
            if (widget !== this.currentWidget) {
                widget.hide();
            }
            this.stackedPanel.insertWidget(index, widget);
            this.tabBar.insertTab(index, widget.title);
            widget.node.setAttribute('role', 'tabpanel');
            var renderer = this.tabBar.renderer;
            if (renderer instanceof exports.TabBar.Renderer) {
                var tabId = renderer.createTabKey({
                    title: widget.title,
                    current: false,
                    zIndex: 0
                });
                widget.node.setAttribute('aria-labelledby', tabId);
            }
        };
        /**
         * Handle the `currentChanged` signal from the tab bar.
         */
        TabPanel.prototype._onCurrentChanged = function (sender, args) {
            // Extract the previous and current title from the args.
            var previousIndex = args.previousIndex, previousTitle = args.previousTitle, currentIndex = args.currentIndex, currentTitle = args.currentTitle;
            // Extract the widgets from the titles.
            var previousWidget = previousTitle ? previousTitle.owner : null;
            var currentWidget = currentTitle ? currentTitle.owner : null;
            // Hide the previous widget.
            if (previousWidget) {
                previousWidget.hide();
            }
            // Show the current widget.
            if (currentWidget) {
                currentWidget.show();
            }
            // Emit the `currentChanged` signal for the tab panel.
            this._currentChanged.emit({
                previousIndex: previousIndex,
                previousWidget: previousWidget,
                currentIndex: currentIndex,
                currentWidget: currentWidget
            });
            // Flush the message loop on IE and Edge to prevent flicker.
            if (domutils.Platform.IS_EDGE || domutils.Platform.IS_IE) {
                messaging.MessageLoop.flush();
            }
        };
        /**
         * Handle the `tabAddRequested` signal from the tab bar.
         */
        TabPanel.prototype._onTabAddRequested = function (sender, args) {
            this._addRequested.emit(sender);
        };
        /**
         * Handle the `tabActivateRequested` signal from the tab bar.
         */
        TabPanel.prototype._onTabActivateRequested = function (sender, args) {
            args.title.owner.activate();
        };
        /**
         * Handle the `tabCloseRequested` signal from the tab bar.
         */
        TabPanel.prototype._onTabCloseRequested = function (sender, args) {
            args.title.owner.close();
        };
        /**
         * Handle the `tabMoved` signal from the tab bar.
         */
        TabPanel.prototype._onTabMoved = function (sender, args) {
            this.stackedPanel.insertWidget(args.toIndex, args.title.owner);
        };
        /**
         * Handle the `widgetRemoved` signal from the stacked panel.
         */
        TabPanel.prototype._onWidgetRemoved = function (sender, widget) {
            widget.node.removeAttribute('role');
            widget.node.removeAttribute('aria-labelledby');
            this.tabBar.removeTab(widget.title);
        };
        return TabPanel;
    }(exports.Widget));
    /**
     * The namespace for the module implementation details.
     */
    var Private;
    (function (Private) {
        /**
         * Convert a tab placement to tab bar orientation.
         */
        function orientationFromPlacement(plc) {
            return placementToOrientationMap[plc];
        }
        Private.orientationFromPlacement = orientationFromPlacement;
        /**
         * Convert a tab placement to a box layout direction.
         */
        function directionFromPlacement(plc) {
            return placementToDirectionMap[plc];
        }
        Private.directionFromPlacement = directionFromPlacement;
        /**
         * A mapping of tab placement to tab bar orientation.
         */
        var placementToOrientationMap = {
            top: 'horizontal',
            left: 'vertical',
            right: 'vertical',
            bottom: 'horizontal'
        };
        /**
         * A mapping of tab placement to box layout direction.
         */
        var placementToDirectionMap = {
            top: 'top-to-bottom',
            left: 'left-to-right',
            right: 'right-to-left',
            bottom: 'bottom-to-top'
        };
    })(Private || (Private = {}));

    exports.AccordionLayout = AccordionLayout;
    exports.BoxSizer = BoxSizer;
    exports.ContextMenu = ContextMenu;
    exports.DockLayout = DockLayout;
    exports.FocusTracker = FocusTracker;
    exports.LayoutItem = LayoutItem;
    exports.Panel = Panel;
    exports.PanelLayout = PanelLayout;
    exports.ScrollBar = ScrollBar;
    exports.SingletonLayout = SingletonLayout;
    exports.StackedLayout = StackedLayout;
    exports.StackedPanel = StackedPanel;
    exports.TabPanel = TabPanel;
    exports.Title = Title;

    Object.defineProperty(exports, '__esModule', { value: true });

})));
//# sourceMappingURL=index.js.map
