(function () {
  'use strict';

  var header = document.getElementById('siteHeader');
  var nav = document.getElementById('primaryNav');
  var burger = document.getElementById('burger');
  var navToggle = nav && nav.querySelector('.nav__toggle');
  var mqDesktop = window.matchMedia('(min-width: 60.0625rem)');

  /* ---------- mobile menu ---------- */
  function closeMenu() {
    if (!nav || !burger) return;
    nav.classList.remove('is-open');
    burger.setAttribute('aria-expanded', 'false');
    burger.setAttribute('aria-label', 'Open menu');
  }

  if (burger && nav) {
    burger.addEventListener('click', function () {
      var open = nav.classList.toggle('is-open');
      burger.setAttribute('aria-expanded', String(open));
      burger.setAttribute('aria-label', open ? 'Close menu' : 'Open menu');
    });

    document.addEventListener('click', function (e) {
      if (mqDesktop.matches) return;
      if (!nav.contains(e.target) && !burger.contains(e.target)) closeMenu();
    });

    nav.addEventListener('click', function (e) {
      if (!mqDesktop.matches && e.target.closest('a')) closeMenu();
    });
  }

  document.addEventListener('keydown', function (e) {
    if (e.key !== 'Escape') return;
    closeMenu();
    if (navToggle) navToggle.setAttribute('aria-expanded', 'false');
  });

  mqDesktop.addEventListener('change', function (e) {
    if (e.matches) closeMenu();
  });

  /* ---------- Tours submenu ---------- */
  if (navToggle) {
    navToggle.addEventListener('click', function () {
      var open = navToggle.getAttribute('aria-expanded') === 'true';
      navToggle.setAttribute('aria-expanded', String(!open));
    });
  }

  /* ---------- mobile "Book now" inside the menu ---------- */
  var desktopCta = document.querySelector('.header__cta');
  var navList = nav && nav.querySelector('.nav__list');
  if (desktopCta && navList) {
    var li = document.createElement('li');
    li.className = 'nav__mobile-cta';
    var clone = desktopCta.cloneNode(true);
    clone.classList.remove('header__cta');
    clone.classList.add('nav__cta');
    li.appendChild(clone);
    navList.appendChild(li);
  }

  /* ---------- sticky header past the hero ---------- */
  var hero = document.querySelector('.hero, .hero-tour');
  if (header && hero && 'IntersectionObserver' in window) {
    var sentinel = document.createElement('div');
    sentinel.setAttribute('aria-hidden', 'true');
    sentinel.style.cssText = 'position:absolute;top:0;left:0;width:1px;height:60vh;pointer-events:none';
    hero.appendChild(sentinel);

    new IntersectionObserver(function (entries) {
      header.classList.toggle('is-stuck', !entries[0].isIntersecting);
    }, { threshold: 0 }).observe(sentinel);
  }

  /* ---------- card rails (prev / next) ---------- */
  function railStep(rail) {
    var card = rail.firstElementChild;
    if (!card) return rail.clientWidth;
    var gap = parseFloat(getComputedStyle(rail).columnGap) || 0;
    return card.getBoundingClientRect().width + gap;
  }

  function syncRailButtons(rail, prev, next) {
    var max = rail.scrollWidth - rail.clientWidth - 1;
    if (prev) prev.disabled = rail.scrollLeft <= 0;
    if (next) next.disabled = rail.scrollLeft >= max;
  }

  Array.prototype.forEach.call(document.querySelectorAll('.rail'), function (rail) {
    var prev = document.querySelector('[data-rail-prev="' + rail.id + '"]');
    var next = document.querySelector('[data-rail-next="' + rail.id + '"]');

    if (prev) prev.addEventListener('click', function () {
      rail.scrollBy({ left: -railStep(rail), behavior: 'smooth' });
    });
    if (next) next.addEventListener('click', function () {
      rail.scrollBy({ left: railStep(rail), behavior: 'smooth' });
    });

    rail.addEventListener('scroll', function () {
      syncRailButtons(rail, prev, next);
    }, { passive: true });
    window.addEventListener('resize', function () {
      syncRailButtons(rail, prev, next);
    });
    syncRailButtons(rail, prev, next);
  });

  /* ---------- testimonials marquee: duplicate for a seamless loop ---------- */
  var marquee = document.querySelector('[data-marquee] .marquee__track');
  if (marquee) {
    var originals = Array.prototype.slice.call(marquee.children);
    originals.forEach(function (node) {
      var copy = node.cloneNode(true);
      copy.setAttribute('aria-hidden', 'true');
      marquee.appendChild(copy);
    });
  }

  /* ---------- FAQ accordion ---------- */
  var accordion = document.querySelector('[data-accordion]');
  if (accordion) {
    accordion.addEventListener('click', function (e) {
      var btn = e.target.closest('.acc__q');
      if (!btn) return;
      var open = btn.getAttribute('aria-expanded') === 'true';
      Array.prototype.forEach.call(accordion.querySelectorAll('.acc__q'), function (other) {
        other.setAttribute('aria-expanded', 'false');
      });
      btn.setAttribute('aria-expanded', String(!open));
    });
  }

  /* ---------- date field: text placeholder, native picker on focus ---------- */
  var dateField = document.querySelector('[data-datefield]');
  if (dateField) {
    dateField.addEventListener('focus', function () {
      dateField.type = 'date';
      if (typeof dateField.showPicker === 'function') {
        try { dateField.showPicker(); } catch (err) { /* not user-activated */ }
      }
    });
    dateField.addEventListener('blur', function () {
      if (!dateField.value) dateField.type = 'text';
    });
  }

  /* ---------- booking form ---------- */
  var form = document.getElementById('booking');
  if (form) {
    form.addEventListener('submit', function (e) {
      e.preventDefault();
      var data = Object.fromEntries(new FormData(form).entries());
      console.log('Booking request', data);
    });
  }

  /* ---------- tour details: check availability ---------- */
  var availability = document.getElementById('availability');
  if (availability) {
    availability.addEventListener('submit', function (e) {
      e.preventDefault();
      console.log('Availability request');
    });
  }


  /* ---------- tour archive: filtering, sorting, pagination ---------- */
  var filters = document.getElementById('filters');
  var grid = document.getElementById('tourGrid');

  if (filters && grid) {
    var PER_PAGE = 9;
    /* the card the design highlights — the middle one of a full row of three */
    var HIGHLIGHT = 4;

    var items = Array.prototype.slice.call(grid.querySelectorAll('.titem'));
    var pager = document.getElementById('pager');
    var pagerPages = document.getElementById('pagerPages');
    var prevBtn = pager && pager.querySelector('[data-page="prev"]');
    var nextBtn = pager && pager.querySelector('[data-page="next"]');
    var countEl = document.getElementById('resultCount');
    var emptyEl = document.getElementById('tourEmpty');
    var resetBtns = Array.prototype.slice.call(document.querySelectorAll('[data-reset]'));
    var searchInput = filters.querySelector('#f-q');

    var matches = items.slice();
    var page = 1;
    var searchTimer = null;

    function value(name) {
      var field = filters.elements[name];
      return field ? field.value : '';
    }

    function checked(name) {
      var field = filters.elements[name];
      return !!(field && field.checked);
    }

    function readFilters() {
      return {
        /* every word has to appear, so "night sydney" finds the same tour
           as "sydney night" */
        words: value('q').trim().toLowerCase().split(/\s+/).filter(Boolean),
        destination: value('destination'),
        category: value('category'),
        price: value('price'),
        duration: value('duration'),
        sort: value('sort') || 'newest',
        freeCancellation: checked('free-cancellation'),
        bestDeal: checked('best-deal'),
        likelyToSellOut: checked('likely-to-sell-out')
      };
    }

    function isFiltered(f) {
      return !!(f.words.length || f.destination || f.category || f.price || f.duration ||
        f.freeCancellation || f.bestDeal || f.likelyToSellOut);
    }

    /* ranges are inclusive at the top and exclusive at the bottom, so "$50 - $100"
       and "Up to $50" tile without both claiming a $50 tour */
    function inPriceRange(price, range) {
      if (!range) return true;
      if (range === '200-plus') return price > 200;
      var bounds = range.split('-');
      var low = Number(bounds[0]);
      var high = Number(bounds[1]);
      return (low === 0 || price > low) && price <= high;
    }

    function keeps(el, f) {
      var data = el.dataset;
      if (f.destination && data.city !== f.destination) return false;
      if (f.category && data.category !== f.category) return false;
      if (f.duration && data.duration !== f.duration) return false;
      if (!inPriceRange(Number(data.price), f.price)) return false;
      if (f.freeCancellation && data.freeCancellation !== 'true') return false;
      if (f.bestDeal && data.bestDeal !== 'true') return false;
      if (f.likelyToSellOut && data.likelyToSellOut !== 'true') return false;
      return f.words.every(function (word) {
        return data.search.indexOf(word) > -1;
      });
    }

    var SORTS = {
      newest: function (a, b) { return Number(b.dataset.added) - Number(a.dataset.added); },
      'price-asc': function (a, b) { return Number(a.dataset.price) - Number(b.dataset.price); },
      'price-desc': function (a, b) { return Number(b.dataset.price) - Number(a.dataset.price); },
      rating: function (a, b) { return Number(b.dataset.rating) - Number(a.dataset.rating); },
      duration: function (a, b) { return durationDays(a) - durationDays(b); }
    };

    function durationDays(el) {
      return el.dataset.duration === 'half-day' ? 0.5 : Number(el.dataset.duration);
    }

    function pageNumbers(total, current) {
      var pages = [];
      var n;

      /* a short run fits without an ellipsis */
      if (total <= 7) {
        for (n = 1; n <= total; n++) pages.push(n);
        return pages;
      }

      var push = function (n) {
        if (n >= 1 && n <= total && pages.indexOf(n) < 0) pages.push(n);
      };
      push(1);
      push(current - 1);
      push(current);
      push(current + 1);
      push(total);
      pages.sort(function (a, b) { return a - b; });

      var out = [];
      pages.forEach(function (n, i) {
        if (i > 0 && n - pages[i - 1] > 1) out.push(null); /* an ellipsis */
        out.push(n);
      });
      return out;
    }

    function renderPager(totalPages) {
      if (!pager) return;
      pager.hidden = totalPages < 2;

      if (pagerPages) {
        var html = '';
        pageNumbers(totalPages, page).forEach(function (n) {
          if (n === null) {
            html += '<span class="pager__gap" aria-hidden="true">&hellip;</span>';
            return;
          }
          html += '<button class="pager__num' + (n === page ? ' is-current' : '') +
            '" type="button" data-page="' + n + '"' +
            (n === page ? ' aria-current="page"' : '') +
            ' aria-label="Page ' + n + '">' + n + '</button>';
        });
        pagerPages.innerHTML = html;
      }

      if (prevBtn) prevBtn.disabled = page === 1;
      if (nextBtn) nextBtn.disabled = page === totalPages;
    }

    /* built from numbers only, so the markup here is safe to assign as HTML */
    function countText(start, shownCount) {
      var total = matches.length;
      if (!total) return 'No tours found';
      var noun = total === 1 ? 'tour' : 'tours';
      if (shownCount === total) return 'Showing <b>' + total + '</b> ' + noun;
      return 'Showing <b>' + (start + 1) + '&ndash;' + (start + shownCount) +
        '</b> of <b>' + total + '</b> ' + noun;
    }

    function render() {
      var totalPages = Math.max(1, Math.ceil(matches.length / PER_PAGE));
      if (page > totalPages) page = totalPages;

      var start = (page - 1) * PER_PAGE;
      var shown = matches.slice(start, start + PER_PAGE);

      items.forEach(function (el) {
        el.hidden = true;
        setHighlight(el, false);
      });

      /* re-order the DOM so the sort order is what a keyboard/screen reader sees */
      matches.forEach(function (el) {
        grid.appendChild(el);
      });

      shown.forEach(function (el, i) {
        el.hidden = false;
        setHighlight(el, shown.length > HIGHLIGHT && i === HIGHLIGHT);
      });

      if (countEl) countEl.innerHTML = countText(start, shown.length);
      if (emptyEl) emptyEl.hidden = matches.length > 0;

      renderPager(totalPages);
    }

    function setHighlight(el, on) {
      el.classList.toggle('is-active', on);
      var card = el.querySelector('.dcard');
      var badge = el.querySelector('.ring-badge--card');
      if (card) card.classList.toggle('is-active', on);
      if (badge) badge.classList.toggle('ring-badge--accent', on);
    }

    function apply(resetPage) {
      var f = readFilters();
      matches = items.filter(function (el) { return keeps(el, f); });
      matches.sort(SORTS[f.sort] || SORTS.newest);
      if (resetPage !== false) page = 1;
      resetBtns.forEach(function (btn) { btn.hidden = !isFiltered(f); });
      render();
    }

    function goToPage(next, totalPages) {
      if (next < 1 || next > totalPages || next === page) return;
      page = next;
      render();
      var list = document.getElementById('tour-list');
      if (list) list.scrollIntoView({ block: 'start', behavior: 'smooth' });
    }

    filters.addEventListener('submit', function (e) {
      e.preventDefault();
      apply();
    });

    filters.addEventListener('change', function () {
      apply();
    });

    if (searchInput) {
      searchInput.addEventListener('input', function () {
        window.clearTimeout(searchTimer);
        searchTimer = window.setTimeout(apply, 200);
      });
    }

    resetBtns.forEach(function (btn) {
      btn.addEventListener('click', function () {
        filters.reset();
        apply();
        filters.scrollIntoView({ block: 'center', behavior: 'smooth' });
      });
    });

    if (pagerPages) {
      pagerPages.addEventListener('click', function (e) {
        var btn = e.target.closest('[data-page]');
        if (!btn) return;
        goToPage(Number(btn.getAttribute('data-page')),
          Math.max(1, Math.ceil(matches.length / PER_PAGE)));
      });
    }

    if (prevBtn) prevBtn.addEventListener('click', function () {
      goToPage(page - 1, Math.max(1, Math.ceil(matches.length / PER_PAGE)));
    });
    if (nextBtn) nextBtn.addEventListener('click', function () {
      goToPage(page + 1, Math.max(1, Math.ceil(matches.length / PER_PAGE)));
    });

    apply();
  }
})();