{# `languages` is `site.languages`; `blog_index_urls` is
   `site.blog_index_urls` — both always present regardless of template.
   `translations` is the current document's translations dict
   (`post.translations`/`page.translations`), or `{}` — passed in
   explicitly by the caller instead of this macro reading an ambient
   `post`/`page` off the caller's context, since an *imported* macro
   doesn't inherit that context by default, and `post`/`page` don't
   exist at all on non-document templates (blog, taxonomy, 404) in the
   first place. Renders nothing for a single-language site. #}
{% macro render_lang_switcher(languages, current_lang, blog_index_urls, translations={}) %}
{% if languages|length > 1 %}
<nav class="lang-switcher" aria-label="idiomas">
    <ul>
        {% for switch_lang in languages %}
        {% set translated = translations.get(switch_lang) %}
        <li>
            {% if switch_lang == current_lang %}
            <span class="lang-switcher__current" aria-current="true">{{ switch_lang }}</span>
            {% elif translated %}
            <a href="{{ translated.url }}" hreflang="{{ switch_lang }}">{{ switch_lang }}</a>
            {% else %}
            <a href="{{ blog_index_urls.get(switch_lang, '/') }}" hreflang="{{ switch_lang }}">{{
                switch_lang }}</a>
            {% endif %}
        </li>
        {% endfor %}
    </ul>
</nav>
{% endif %}
{% endmacro %}