{# Generates the main and basic menu from context data in the site's
   configuration file.
#}
{% macro render_basic_menu() -%}
<ul class="basic">
{% for menu_item in menu %}
    <li><a {% if (menu_item.url == resource.relative_path) %}class="selected" {% endif -%}
        href="{{ content_url(menu_item.url) }}">{{ menu_item.title }}</a></li>
{% endfor %}
</ul>
{%- endmacro %}


{# Generates the advanced menu from all files located in the content/advanced
   folder. Only advanced section files have 'index' metadata, so we can be
   certain that no other files will creep in.
#}
{% macro render_advanced_menu() -%}
<ul class="advanced">
{% for res in site.content.walk_resources_sorted_by_index() %}
    <li><a {% if (res.url == resource.url) %}class="selected" {% endif -%}
        href="{{ res.full_url }}">{{ res.meta.title }}</a></li>
{% endfor %}
</ul>
{%- endmacro %}


{# Advanced topics macro. Renders navigation at the end of an advanced
   article. It also depends on 'index' metadata.
#}
{% macro render_bottom_article_nav() %}
<div class="bottom_article_nav">
{% if resource.next_by_index is not none -%}
    <div class="next"><a href="{{ resource.next_by_index.full_url }}">
    {{ resource.next_by_index.meta.title }}</a>
    &gt;</div>
{%- endif %}

{% if resource.prev_by_index is not none -%}
    <div class="prev">&lt; <a href="{{ resource.prev_by_index.full_url }}">
    {{ resource.prev_by_index.meta.title }}</a>
    </div>
{%- endif %}
</div>
{% endmacro %}