<!--
  Copyright (c) 2016-2023 Martin Donath <martin.donath@squidfunk.com>

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to
  deal in the Software without restriction, including without limitation the
  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  sell copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  IN THE SOFTWARE.
-->

<!-- Render navigation link status -->
{% macro render_status(nav_item, type) %}
  {% set class = "md-status md-status--" ~ type %}

  <!-- Render icon with title (or tooltip), if given -->
  {% if config.extra.status and config.extra.status[type] %}
    <span
      class="{{ class }}"
      title="{{ config.extra.status[type] }}"
    >
    </span>

  <!-- Render icon only -->
  {% else %}
    <span class="{{ class }}"></span>
  {% endif %}
{% endmacro %}

<!-- Render navigation link content -->
{% macro render_content(nav_item, ref = nav_item) %}

  <!-- Navigation link icon -->
  {% if nav_item.is_page and nav_item.meta.icon %}
    {% include ".icons/" ~ nav_item.meta.icon ~ ".svg" %}
  {% endif %}

  <!-- Navigation link title -->
  <span class="md-ellipsis">
    {{ ref.title }}
  </span>

  <!-- Navigation link status -->
  {% if nav_item.is_page and nav_item.meta.status %}
    {{ render_status(nav_item, nav_item.meta.status) }}
  {% endif %}
{% endmacro %}

<!-- Render navigation item (pruned) -->
{% macro render_pruned(nav_item, ref = nav_item) %}
  {% set first = nav_item.children | first %}

  <!-- Recurse, if the first item has further nested items -->
  {% if first and first.children %}
    {{ render_pruned(first, ref) }}

  <!-- Navigation link -->
  {% else %}
    <a href="{{ first.url | url }}" class="md-nav__link">
      {{ render_content(ref) }}

      <!-- Only render toggle if there's at least one nested item -->
      {% if nav_item.children | length > 0 %}
        <span class="md-nav__icon md-icon"></span>
      {% endif %}
    </a>
  {% endif %}
{% endmacro %}

<!-- Render navigation item -->
{% macro render(nav_item, path, level) %}

  <!-- Determine classes -->
  {% set class = "md-nav__item" %}
  {% if nav_item.active %}
    {% set class = class ~ " md-nav__item--active" %}
  {% endif %}

  <!-- Navigation item with nested items -->
  {% if nav_item.children %}

    <!-- Determine all nested items that are index pages -->
    {% set indexes = [] %}
    {% if "navigation.indexes" in features %}
      {% for nav_item in nav_item.children %}
        {% if nav_item.is_index and not index is defined %}
          {% set _ = indexes.append(nav_item) %}
        {% endif %}
      {% endfor %}
    {% endif %}

    <!-- Determine whether to render item as a section -->
    {% if "navigation.sections" in features and level == 1 + (
      "navigation.tabs" in features
    ) %}
      {% set class = class ~ " md-nav__item--section" %}

    <!-- Determine whether to prune inactive item -->
    {% elif not nav_item.active and "navigation.prune" in features %}
      {% set class = class ~ " md-nav__item--pruned" %}
      {% set prune = true %}
    {% endif %}

    <!-- Nested navigation item -->
    <li class="{{ class }} md-nav__item--nested">
      {% if not prune %}
        {% set expanded = "navigation.expand" in features %}
        {% set active = nav_item.active or expanded %}

        <!-- Determine checked and indeterminate state -->
        {% set checked = "checked" if nav_item.active %}
        {% if expanded and not checked %}
          {% set indeterminate = "md-toggle--indeterminate" %}
        {% endif %}

        <!-- Active checkbox expands items contained within nested section -->
        <input
          class="md-nav__toggle md-toggle {{ indeterminate }}"
          type="checkbox"
          id="{{ path }}"
          {{ checked }}
        />

        <!-- Toggle to expand nested items -->
        {% if not indexes %}
          <label
            class="md-nav__link"
            for="{{ path }}"
            id="{{ path }}_label"
            tabindex="0"
          >
            {{ render_content(nav_item) }}
            <span class="md-nav__icon md-icon"></span>
          </label>

        <!-- Toggle to expand nested items with link to index page -->
        {% else %}
          {% set index = indexes | first %}
          {% set class = "md-nav__link--active" if index == page %}
          <div class="md-nav__link md-nav__container">
            <a
              href="{{ index.url | url }}"
              class="md-nav__link {{ class }}"
            >
              {{ render_content(index, nav_item) }}
            </a>

            <!-- Only render toggle if there's at least one more page -->
            {% if nav_item.children | length > 1 %}
              <label class="md-nav__link {{ class }}" for="{{ path }}">
                <span class="md-nav__icon md-icon"></span>
              </label>
            {% endif %}
          </div>
        {% endif %}

        <!-- Nested navigation -->
        <nav
          class="md-nav"
          data-md-level="{{ level }}"
          aria-labelledby="{{ path }}_label"
          aria-expanded="{{ nav_item.active | tojson }}"
        >
          <label class="md-nav__title" for="{{ path }}">
            <span class="md-nav__icon md-icon"></span>
            {{ nav_item.title }}
          </label>
          <ul class="md-nav__list" data-md-scrollfix>

            <!-- Nested navigation item -->
            {% for nav_item in nav_item.children %}
              {% if not indexes or nav_item != indexes | first %}
                {{ render(nav_item, path ~ "_" ~ loop.index, level + 1) }}
              {% endif %}
            {% endfor %}
          </ul>
        </nav>

      <!-- Pruned navigation item -->
      {% else %}
        {{ render_pruned(nav_item) }}
      {% endif %}
    </li>

  <!-- Currently active page -->
  {% elif nav_item == page %}
    <li class="{{ class }}">
      {% set toc = page.toc %}

      <!-- State toggle -->
      <input
        class="md-nav__toggle md-toggle"
        type="checkbox"
        id="__toc"
      />

      <!-- Hack: see partials/toc.html for more information -->
      {% set first = toc | first %}
      {% if first and first.level == 1 %}
        {% set toc = first.children %}
      {% endif %}

      <!-- Navigation link to table of contents -->
      {% if toc %}
        <label class="md-nav__link md-nav__link--active" for="__toc">
          {{ render_content(nav_item) }}
          <span class="md-nav__icon md-icon"></span>
        </label>
      {% endif %}
      <a
        href="{{ nav_item.url | url }}"
        class="md-nav__link md-nav__link--active"
      >
        {{ render_content(nav_item) }}
      </a>

      <!-- Table of contents -->
      {% if toc %}
        {% include "partials/toc.html" %}
      {% endif %}
    </li>

  <!-- Navigation item -->
  {% else %}
    <li class="{{ class }}">
      <a href="{{ nav_item.url | url }}" class="md-nav__link">
        {{ render_content(nav_item) }}
      </a>
    </li>
  {% endif %}
{% endmacro %}
