{% load i18n %}
{% comment %}
Progress (STA-007): a determinate or indeterminate progress bar. Structural,
consumed via {% include %} (no render-time enforcement needed, unlike the
tagged components).

Determinate (``value`` supplied): role="progressbar" carries aria-valuenow/
-valuemin="0"/-valuemax="100" and an accessible name (aria-label, from
``label``). The fill's width is driven by the --bw-progress-value custom
property (an unqualified 0-100 number, NOT a percentage string), which the
CSS turns into a length with `width: calc(var(--bw-progress-value) * 1%)`.
Colour is never the only signal: the track/fill pairing carries visible
contrast on its own, and the accessible name plus the optional visible
``show_value`` text carry the state as words, not just as fill length or
hue.

Indeterminate (``value`` omitted or None): aria-valuenow is omitted entirely
(an indeterminate progressbar has no "now" to report, matching the native
<progress> element without a value attribute), and the fill runs an
animated sweep gated behind prefers-reduced-motion: no-preference. Under
reduced motion the sweep stops and a static partial fill (bw-progress__fill
carries a fixed inline-size instead of animating) stands in as the "work is
in progress" signal, so reduced motion never leaves a blank track with no
indication anything is happening.

Required context:
  label: the accessible name (a plain string, rendered via aria-label). Every
      progress bar names what it is progress OF (STA-007): a progress bar
      with no label is an authoring error (structural include, so this
      cannot raise at render time; the docstring is the enforcement).
Optional:
  value (int, 0-100): determinate progress. Omitted renders the
      indeterminate treatment.
  show_value (bool, default False): also renders the percentage as visible
      text beside the bar (determinate only; ignored when indeterminate,
      since there is no percentage to show).
{% endcomment %}
<div class="bw-progress{% if value is None %} bw-progress--indeterminate{% endif %}"
     role="progressbar"
     aria-label="{{ label }}"
     aria-valuemin="0"
     aria-valuemax="100"
     {% if value is not None %}aria-valuenow="{{ value }}"{% endif %}>
  <div class="bw-progress__track">
    {% if value is not None %}
      <div class="bw-progress__fill" style="--bw-progress-value: {{ value }}"></div>
    {% else %}
      <div class="bw-progress__fill bw-progress__fill--indeterminate"></div>
    {% endif %}
  </div>
  {% if show_value and value is not None %}
    <span class="bw-progress__value">{% blocktranslate with percent=value %}{{ percent }}%{% endblocktranslate %}</span>
  {% endif %}
</div>