// Shared docs-site behaviors. Loaded at the bottom of every page.
//
// Sidebar active-pill sync: the .active class on sidebar links is
// baked into each HTML file as a baseline (page-level link only),
// which means clicking an in-page anchor link (e.g. "Discount codes"
// → index.html#discounts) leaves the pill stuck on whatever the
// statically-marked page link was. This script keeps the active
// state in sync with the current URL hash so the pill follows
// what the user clicked.
(function () {
  var sidebarLinks = Array.prototype.slice.call(
    document.querySelectorAll('aside.side a')
  );
  if (!sidebarLinks.length) return;

  var currentFile = (location.pathname.split('/').pop() || 'index.html');

  function findActive(hash) {
    var desired = hash ? (currentFile + hash) : currentFile;
    var match = null;
    sidebarLinks.forEach(function (a) {
      if (a.getAttribute('href') === desired) match = a;
    });
    if (match) return match;
    // Fallback: bare current-file link when no hash matches
    sidebarLinks.forEach(function (a) {
      if (a.getAttribute('href') === currentFile) match = a;
    });
    return match;
  }

  function setActive(link) {
    if (!link) return;
    sidebarLinks.forEach(function (a) { a.classList.remove('active'); });
    link.classList.add('active');
  }

  setActive(findActive(location.hash));

  window.addEventListener('hashchange', function () {
    setActive(findActive(location.hash));
  });

  sidebarLinks.forEach(function (a) {
    a.addEventListener('click', function () {
      setActive(a);
    });
  });
})();