<header class="md-header" data-md-component="header">
  <nav class="md-header-nav md-grid">
    <div class="md-flex">
      <div class="md-flex__cell md-flex__cell--shrink">
        <a href="{{ config.site_url | default(nav.homepage.url, true) | url }}" title="{{ config.site_name }}" class="md-header-nav__button md-logo">
          {% if config.theme.logo.icon %}
            <i class="md-icon">{{ config.theme.logo.icon }}</i>
          {% else %}
            <img src="{{ config.theme.logo | url }}" width="24" height="24">
          {% endif %}
        </a>
      </div>
      <div class="md-flex__cell md-flex__cell--shrink">
        <label class="md-icon md-icon--menu md-header-nav__button" for="__drawer"></label>
      </div>
      <div class="md-flex__cell md-flex__cell--stretch">
        <div class="md-flex__ellipsis md-header-nav__title" data-md-component="title">
          {% block site_name %}
            {% if config.site_name == page.title %}
              {{ config.site_name }}
            {% else %}
              <span class="md-header-nav__topic">
                {{ config.site_name }}
              </span>
              <span class="md-header-nav__topic">
                {{ page.title }}
              </span>
            {% endif %}
          {% endblock %}
        </div>
      </div>
      <div class="md-flex__cell md-flex__cell--shrink">
        {% block search_box %}
          {% if "search" in config["plugins"] %}
            <label class="md-icon md-icon--search md-header-nav__button" for="__search"></label>
            {% include "partials/search.html" %}
          {% endif %}
        {% endblock %}
      </div>

      <!-- netdata -->
      <style>
        .language-selector li {
          list-style: none;
        }

        .language-option.selected {
          background-color: #ccc;
        }
      </style>
      <script>
        function getLanguage() {
          const lang = window.location.pathname.split("/")[1];

          if (lang.length == 0 || lang.length > 2) {
            return "en";
          }

          return lang;
        }

        function languagePrefix(lang) {
          if (lang === "en") {
            return "";
          }

          return `/${lang}`;
        }

        function updatePathname(pathname, lang) {
          if (currentLang !== "en") {
            const parts = pathname.split("/");
            parts.shift();
            parts.shift();
            pathname = `/${parts.join("/")}`;
          }

          return `${languagePrefix(lang)}${pathname}`;
        }

        function setLanguage(sel) {
          if (sel.value === currentLang) {
            return;
          }

          window.location.pathname = updatePathname(window.location.pathname, sel.value);
        }
      </script>

      <div style="vertical-align: middle; white-space: nowrap; padding-left: 20px;" class="md-flex__cell md-flex__cell--shrink">
        <img src="/custom/img/geography-16.png" style="vertical-align: middle;"/>
        <select id="sel" onchange="setLanguage(this);" style="vertical-align: middle; background-color: #3f51b5; color: white; border: none;">
          <option href="#" value='en'>English</option>
          <option href="#" value='zh'>中文</option>
        </select>
      </div>

      {% if config.repo_url %}
        <div class="md-flex__cell md-flex__cell--shrink">
          <div class="md-header-nav__source">
            {% include "partials/source.html" %}
          </div>
        </div>
      {% endif %}
    </div>
  </nav>
</header>
