{#-
    stylescape/macros/forms.html.jinja
    ===========================================================================
    Render Django forms with the stylescape form classes (ss-c-form__*).

        {% from "stylescape/macros/forms.html.jinja" import field, form_fields, form, formset with context %}

    Import `with context` so `form()` can read `csrf_input` from the request
    context (the Django Jinja2 backend puts it there).

    field(bound_field, attrs={})
        One BoundField: label (or legend for radio/checkbox groups), widget,
        help text and errors. The widget gets `aria-describedby` pointing at
        the help text and the errors, and `aria-invalid` when it has errors.
    form_fields(form)
        Non-field errors, every visible field, then the hidden fields.
    form(form, action="", method="post", submit=None, cancel_url=None)
        The <form> element with CSRF token, enctype for file fields and the
        actions row. Extra buttons: call it with a block
        ({% call form(f) %}<button …>{% endcall %}).
    formset(formset, legend=None)
        Management form, formset errors and one fieldset per form.
-#}

{%- macro errors(error_list, id=None, nonfield=False) -%}
    {%- if error_list -%}
    {%- if nonfield %}<div role="alert">{% endif %}
    <ul class="ss-c-form__errors{{ ' ss-c-form__errors--nonfield' if nonfield }}"{% if id %} id="{{ id }}"{% endif %}>
        {%- for error in error_list %}
        <li>{{ error }}</li>
        {%- endfor %}
    </ul>
    {%- if nonfield %}</div>{% endif %}
    {%- endif -%}
{%- endmacro %}

{%- macro _is_group(bound_field) -%}
    {#- Radio and checkbox groups render as a fieldset with a legend. -#}
    {%- set widget = bound_field.field.widget -%}
    {{- "1" if widget.allow_multiple_selected is defined and widget.input_type is defined and widget.input_type in ("checkbox", "radio") else "" -}}
{%- endmacro %}

{%- macro field(bound_field, attrs={}) -%}
    {%- set f = bound_field -%}
    {%- set auto_id = f.auto_id or f.html_name -%}
    {%- set help_id = auto_id ~ "_helptext" -%}
    {%- set error_id = auto_id ~ "_error" -%}
    {%- set described = [] -%}
    {%- if f.help_text %}{% set _d = described.append(help_id) %}{% endif -%}
    {%- if f.errors %}{% set _d = described.append(error_id) %}{% endif -%}
    {%- set widget_attrs = dict(attrs) -%}
    {%- if described %}{% set _d = widget_attrs.update({"aria-describedby": described | join(" ")}) %}{% endif -%}
    {%- if f.errors %}{% set _d = widget_attrs.update({"aria-invalid": "true"}) %}{% endif -%}
    {%- set input_type = f.field.widget.input_type if f.field.widget.input_type is defined else "" -%}
    {%- set is_check = input_type == "checkbox" and not _is_group(f) -%}
    {%- set is_group = _is_group(f) or input_type == "radio" -%}
    {%- set classes = ["ss-c-form__field"] -%}
    {%- if is_check %}{% set _d = classes.append("ss-c-form__field--inline") %}{% endif -%}
    {%- if f.errors %}{% set _d = classes.append("ss-c-form__field--invalid") %}{% endif -%}
    <div class="{{ classes | join(' ') }}">
    {%- if is_group %}
        <fieldset class="ss-c-form__fieldset"{% if described %} aria-describedby="{{ described | join(' ') }}"{% endif %}>
            <legend class="ss-c-form__legend">{{ f.label }}{% if f.field.required %}<span class="ss-c-form__required" aria-hidden="true"></span>{% endif %}</legend>
            {{ f.as_widget(attrs=widget_attrs) }}
        </fieldset>
    {%- elif is_check %}
        {#- Label first, as Django renders it; --inline shows the box first and help text below. #}
        <label class="ss-c-form__label" for="{{ f.id_for_label }}">{{ f.label }}</label>
        {{ f.as_widget(attrs=widget_attrs) }}
    {%- else %}
        <label class="ss-c-form__label" for="{{ f.id_for_label }}">{{ f.label }}{% if f.field.required %}<span class="ss-c-form__required" aria-hidden="true"></span>{% endif %}</label>
        {{ f.as_widget(attrs=widget_attrs) }}
    {%- endif %}
    {%- if f.help_text %}
        <div class="ss-c-form__help" id="{{ help_id }}">{{ f.help_text }}</div>
    {%- endif %}
        {{ errors(f.errors, id=error_id) }}
    </div>
{%- endmacro %}

{%- macro form_fields(form) -%}
    {{ errors(form.non_field_errors(), nonfield=True) }}
    {%- for f in form.visible_fields() %}
    {{ field(f) }}
    {%- endfor %}
    {%- for f in form.hidden_fields() %}
    {{ errors(f.errors, nonfield=True) }}{{ f }}
    {%- endfor %}
{%- endmacro %}

{%- macro form(form, action="", method="post", submit=None, cancel_url=None, id=None, attrs="") -%}
    <form class="ss-c-form" action="{{ action }}" method="{{ method }}"
          {%- if id %} id="{{ id }}"{% endif %}
          {%- if form.is_multipart() %} enctype="multipart/form-data"{% endif %}
          {%- if attrs %} {{ attrs }}{% endif %}>
        {%- if method | lower == "post" and csrf_input is defined %}
        {{ csrf_input }}
        {%- endif %}
        {{ form_fields(form) }}
        <div class="ss-c-form__actions">
            <button class="ss-c-button ss-c-button--primary" type="submit">{{ submit or _("Save") }}</button>
            {%- if caller is defined %}{{ caller() }}{% endif %}
            {%- if cancel_url %}
            <a class="ss-c-button ss-c-button--ghost" href="{{ cancel_url }}">{{ _("Cancel") }}</a>
            {%- endif %}
        </div>
    </form>
{%- endmacro %}

{%- macro formset(formset, legend=None) -%}
    <div class="ss-c-form__formset">
        {{ formset.management_form }}
        {{ errors(formset.non_form_errors(), nonfield=True) }}
        {%- for f in formset.forms %}
        <fieldset class="ss-c-form__fieldset">
            <legend class="ss-c-form__legend">{{ legend or _("Item") }} {{ loop.index }}</legend>
            {{ form_fields(f) }}
        </fieldset>
        {%- endfor %}
    </div>
{%- endmacro %}