{# =========================================================================
   Translation helpers for the package's own templates.

   Package templates must render byte-identically in an app that never calls
   coffeehouse_ui.i18n.install (a plain Jinja environment, where {% trans %}
   does not parse and `_` is undefined). So they never use `_` or trans; they
   use these macros:

       {% from "macros/i18n.html" import ch_t, ch_nt %}
       {{ ch_t("Logout") }}
       {{ ch_t("from dept: %(dept)s", dept=slug) }}
       {{ ch_nt("%(num)d role", "%(num)d roles", n) }}
       <div{{ ch_data("data-empty-label", "(empty)") }}>

   - Without install (`ch_i18n` undefined) a macro outputs the English msgid.
   - With install, `ch_i18n` (coffeehouse_ui.i18n.TemplateBridge) translates for
     the request's locale and returns a plain str. It is NOT newstyle `_()`,
     which returns Markup: the translation would skip autoescape, and an `&`
     in a string would render differently from the literal it replaced.
   - Either way the message is escaped like the old literal, so a msgid must
     not contain markup or an entity; keep `&rarr;`, `&times;`, tags outside.
     Named placeholders are filled after escaping: a plain value is escaped,
     a Markup value (a `{% set %}` block holding a link) is inserted as is.
   - ch_data emits ` name="..."` only when the current locale translates the
     msgid, so markup at `en` is unchanged; the script keeps English inside.

   Babel extracts them through the keywords in babel.cfg
   (ch_t ch_nt:1,2 ch_data:2).
   ========================================================================= #}
{%- macro ch_t(msgid) -%}
{%- set _s = ch_i18n.gettext(msgid) if ch_i18n is defined else msgid -%}
{{ (_s | e) % kwargs if kwargs else _s }}
{%- endmacro %}

{%- macro ch_nt(singular, plural, n) -%}
{%- set _s = ch_i18n.ngettext(singular, plural, n) if ch_i18n is defined else (singular if n == 1 else plural) -%}
{{ (_s | e) % dict(kwargs, num=n) }}
{%- endmacro %}

{%- macro ch_data(name, msgid) -%}
{%- if ch_i18n is defined and ch_i18n.translates(msgid) %} {{ name }}="{{ ch_i18n.gettext(msgid) }}"{% endif -%}
{%- endmacro %}