/* ========================================
   G1 Moves — Showcase App
   ======================================== */

(function () {
  'use strict';

  // ------------------------------------
  // State
  // ------------------------------------
  let allClips = [];
  let baseUrl = '';
  let activeCategory = 'all';
  let activeStage = 'retarget';

  // ------------------------------------
  // DOM refs
  // ------------------------------------
  const grid = document.getElementById('clip-grid');
  const emptyState = document.getElementById('empty-state');
  const modal = document.getElementById('pipeline-modal');

  // ------------------------------------
  // Init
  // ------------------------------------
  async function init() {
    try {
      const res = await fetch('data.json');
      const data = await res.json();
      allClips = data.clips;
      baseUrl = data.base_url;
      updateStats(data.stats);
      filterAndRender();
      setupCategoryButtons();
      setupStageButtons();
      setupModal();
      setupScrollReveal();
    } catch (err) {
      grid.innerHTML = '<p style="padding:2rem;color:#888;font-family:monospace;">Failed to load data.json</p>';
    }
  }

  // ------------------------------------
  // Stats
  // ------------------------------------
  function updateStats(stats) {
    setText('stat-total', stats.total);
    setText('stat-dance', stats.dance);
    setText('stat-karate', stats.karate);
    setText('stat-bonus', stats.bonus);
    setText('stat-policies', stats.policies);
  }

  function setText(id, value) {
    const el = document.getElementById(id);
    if (el) el.textContent = value;
  }

  // ------------------------------------
  // Filtering & Rendering
  // ------------------------------------
  function filterAndRender() {
    const filtered = activeCategory === 'all'
      ? allClips
      : allClips.filter(c => c.category === activeCategory);

    grid.innerHTML = '';
    emptyState.classList.toggle('visible', filtered.length === 0);

    filtered.forEach((clip, i) => {
      const card = createCard(clip, i);
      grid.appendChild(card);
    });

    observeLazyImages();
    observeCardReveal();
  }

  // ------------------------------------
  // Card creation
  // ------------------------------------
  function createCard(clip, index) {
    const card = document.createElement('div');
    card.className = 'clip-card';
    card.dataset.clipId = clip.id;

    const stageData = clip.stages[activeStage];
    const mediaSrc = stageData
      ? mediaUrl(stageData)
      : null;
    const isVideo = mediaSrc && mediaSrc.endsWith('.mp4');

    const stages = ['capture', 'retarget', 'training', 'policy'];

    card.innerHTML =
      '<div class="card-media">' +
        (mediaSrc
          ? (isVideo
            ? '<video data-src="' + mediaSrc + '" autoplay muted loop playsinline preload="none" class="lazy-video"></video>'
            : '<img data-src="' + mediaSrc + '" alt="' + escHtml(clip.name) + '" loading="lazy">')
          : '<div class="card-placeholder">Not available</div>') +
        '<div class="card-duration">' + formatDuration(clip.duration) + '</div>' +
        (clip.has_policy ? '<div class="card-badge">TRAINED</div>' : '') +
      '</div>' +
      '<div class="card-info">' +
        '<div class="card-title">' + escHtml(clip.name) + '</div>' +
        '<div class="card-meta">' +
          '<span class="card-category">' + clip.category + '</span>' +
          '<span class="card-separator"></span>' +
          '<span>' + clip.performer + '</span>' +
        '</div>' +
        '<div class="card-stages">' +
          stages.map(function (s) {
            var has = !!clip.stages[s];
            var active = s === activeStage;
            var cls = 'card-stage-btn' +
              (active ? ' active' : '') +
              (has ? '' : ' disabled');
            return '<button class="' + cls + '" data-stage="' + s + '"' +
              (has ? '' : ' disabled') +
              ' title="' + capitalize(s) + '">' +
              s.charAt(0).toUpperCase() +
              '</button>';
          }).join('') +
        '</div>' +
      '</div>';

    // Media click → open modal
    card.querySelector('.card-media').addEventListener('click', function () {
      openModal(clip);
    });

    // Per-card stage buttons
    var stageBtns = card.querySelectorAll('.card-stage-btn:not(.disabled)');
    for (var i = 0; i < stageBtns.length; i++) {
      stageBtns[i].addEventListener('click', (function (btn) {
        return function (e) {
          e.stopPropagation();
          switchCardStage(card, clip, btn.dataset.stage);
        };
      })(stageBtns[i]));
    }

    return card;
  }

  function switchCardStage(card, clip, stage) {
    var stageData = clip.stages[stage];
    if (!stageData) return;

    var src = mediaUrl(stageData);
    var isVideo = src && src.endsWith('.mp4');
    var existing = card.querySelector('.card-media img, .card-media video');
    var placeholder = card.querySelector('.card-placeholder');
    var target = existing || placeholder;

    if (target) {
      var newEl;
      if (isVideo) {
        newEl = document.createElement('video');
        newEl.src = src;
        newEl.autoplay = true;
        newEl.muted = true;
        newEl.loop = true;
        newEl.playsInline = true;
      } else {
        newEl = document.createElement('img');
        newEl.src = src;
        newEl.alt = clip.name;
      }
      target.replaceWith(newEl);
    }

    // Update active state on buttons
    var btns = card.querySelectorAll('.card-stage-btn');
    for (var i = 0; i < btns.length; i++) {
      btns[i].classList.toggle('active', btns[i].dataset.stage === stage);
    }
  }

  // ------------------------------------
  // Lazy loading
  // ------------------------------------
  var lazyObserver = null;

  function observeLazyImages() {
    if (!lazyObserver) {
      lazyObserver = new IntersectionObserver(function (entries) {
        entries.forEach(function (entry) {
          if (entry.isIntersecting) {
            var img = entry.target;
            if (img.dataset.src) {
              img.src = img.dataset.src;
              img.removeAttribute('data-src');
            }
            lazyObserver.unobserve(img);
          }
        });
      }, { rootMargin: '300px' });
    }

    var lazies = grid.querySelectorAll('img[data-src], video[data-src]');
    for (var i = 0; i < lazies.length; i++) {
      lazyObserver.observe(lazies[i]);
    }
  }

  // ------------------------------------
  // Card reveal on scroll
  // ------------------------------------
  var revealObserver = null;

  function observeCardReveal() {
    if (!revealObserver) {
      revealObserver = new IntersectionObserver(function (entries) {
        entries.forEach(function (entry) {
          if (entry.isIntersecting) {
            entry.target.classList.add('visible');
            revealObserver.unobserve(entry.target);
          }
        });
      }, { threshold: 0.05, rootMargin: '40px' });
    }

    var cards = grid.querySelectorAll('.clip-card:not(.visible)');
    for (var i = 0; i < cards.length; i++) {
      // Stagger the transition delay
      cards[i].style.transitionDelay = (i * 0.04) + 's';
      revealObserver.observe(cards[i]);
    }
  }

  // ------------------------------------
  // Category buttons
  // ------------------------------------
  function setupCategoryButtons() {
    var btns = document.querySelectorAll('.category-btn');
    for (var i = 0; i < btns.length; i++) {
      btns[i].addEventListener('click', function () {
        setActiveBtn('.category-btn', this);
        activeCategory = this.dataset.category;
        filterAndRender();
      });
    }
  }

  // ------------------------------------
  // Global stage buttons
  // ------------------------------------
  function setupStageButtons() {
    var btns = document.querySelectorAll('.global-stage-btn');
    for (var i = 0; i < btns.length; i++) {
      btns[i].addEventListener('click', function () {
        setActiveBtn('.global-stage-btn', this);
        activeStage = this.dataset.stage;
        filterAndRender();
      });
    }
  }

  function setActiveBtn(selector, activeEl) {
    var btns = document.querySelectorAll(selector);
    for (var i = 0; i < btns.length; i++) {
      btns[i].classList.toggle('active', btns[i] === activeEl);
    }
  }

  // ------------------------------------
  // Modal
  // ------------------------------------
  function setupModal() {
    var closeBtn = modal.querySelector('.modal-close');
    if (closeBtn) {
      closeBtn.addEventListener('click', closeModal);
    }

    modal.addEventListener('click', function (e) {
      if (e.target === modal) closeModal();
    });

    document.addEventListener('keydown', function (e) {
      if (e.key === 'Escape') closeModal();
    });
  }

  function openModal(clip) {
    var stages = ['capture', 'retarget', 'training', 'policy'];

    modal.querySelector('.modal-title').textContent = clip.name;
    modal.querySelector('.modal-meta').textContent =
      clip.category + '  ·  ' + clip.performer + '  ·  ' +
      formatDuration(clip.duration) + '  ·  ' +
      clip.frames + ' frames @ ' + clip.fps + ' fps';

    var modalGrid = modal.querySelector('.modal-grid');
    modalGrid.innerHTML = stages.map(function (s) {
      var data = clip.stages[s];
      var unavail = !data ? ' unavailable' : '';
      var label = '<div class="modal-stage-label">' + s.toUpperCase() + '</div>';

      if (data) {
        var src = mediaUrl(data);
        var isVid = src && src.endsWith('.mp4');
        var mediaTag = isVid
          ? '<video src="' + src + '" autoplay muted loop playsinline></video>'
          : '<img src="' + src + '" alt="' + escHtml(clip.name) + ' ' + s + '" loading="lazy">';
        return '<div class="modal-stage' + unavail + '">' +
          label + mediaTag +
          '</div>';
      }
      return '<div class="modal-stage' + unavail + '">' +
        label +
        '<div class="modal-placeholder">Not yet available</div>' +
        '</div>';
    }).join('');

    modal.classList.add('open');
    document.body.style.overflow = 'hidden';
  }

  function closeModal() {
    modal.classList.remove('open');
    document.body.style.overflow = '';
    // Pause modal videos to stop background playback
    var videos = modal.querySelectorAll('video');
    for (var i = 0; i < videos.length; i++) {
      videos[i].pause();
    }
  }

  // ------------------------------------
  // Scroll reveal for sections
  // ------------------------------------
  function setupScrollReveal() {
    var sections = document.querySelectorAll('.reveal');
    if (!sections.length) return;

    var observer = new IntersectionObserver(function (entries) {
      entries.forEach(function (entry) {
        if (entry.isIntersecting) {
          entry.target.classList.add('revealed');
          observer.unobserve(entry.target);
        }
      });
    }, { threshold: 0.1 });

    for (var i = 0; i < sections.length; i++) {
      observer.observe(sections[i]);
    }
  }

  // ------------------------------------
  // Utils
  // ------------------------------------
  function mediaUrl(stageData) {
    var file = stageData.mp4 || stageData.gif;
    if (!file) return null;
    return baseUrl ? baseUrl + '/' + file : file;
  }

  function formatDuration(seconds) {
    var m = Math.floor(seconds / 60);
    var s = Math.round(seconds % 60);
    return m + ':' + (s < 10 ? '0' : '') + s;
  }

  function capitalize(str) {
    return str.charAt(0).toUpperCase() + str.slice(1);
  }

  function escHtml(str) {
    var div = document.createElement('div');
    div.textContent = str;
    return div.innerHTML;
  }

  // ------------------------------------
  // Boot
  // ------------------------------------
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
  } else {
    init();
  }
})();