'use strict';

let lbIndex = 0;

function openLightbox(i) {
  lbIndex = i;
  renderLightbox();
  document.getElementById('lightbox').classList.remove('hidden');
  document.body.style.overflow = 'hidden';
  document.addEventListener('keydown', lbKey);
}

function closeLightbox() {
  document.getElementById('lightbox').classList.add('hidden');
  document.body.style.overflow = '';
  document.removeEventListener('keydown', lbKey);
  ['lb-video', 'lb-audio'].forEach(id => {
    const el = document.getElementById(id);
    el.pause && el.pause();
  });
  history.replaceState(null, '', location.pathname + location.search);
}

function lbNav(delta) {
  let next = lbIndex + delta;
  while (next >= 0 && next < ENTRIES.length && !ENTRIES[next].type) next += delta;
  if (next >= 0 && next < ENTRIES.length) {
    lbIndex = next;
    renderLightbox();
  }
}

function lbToggleInfo() {
  document.getElementById('lb-info-panel').classList.toggle('hidden');
}

function lbBuildInfo(e) {
  const rows = [];
  if (e.name !== e.title) rows.push(['File', e.name]);
  if (e.taken_at) {
    const d = new Date(e.taken_at.replace(/[+-]\d{2}:\d{2}$|Z$/, ''));
    rows.push(['Date', d.toLocaleString(undefined, { dateStyle: 'medium', timeStyle: 'short' })]);
  }
  if (e.width && e.height) rows.push(['Dimensions', `${e.width} × ${e.height}`]);
  document.getElementById('lb-info-dl').innerHTML =
    rows.map(([k, v]) => `<dt>${k}</dt><dd>${v}</dd>`).join('');
  document.getElementById('lb-info-panel').classList.add('hidden');
  document.getElementById('lb-info-btn').style.display = rows.length ? '' : 'none';
}

function renderLightbox() {
  const e   = ENTRIES[lbIndex];
  const img = document.getElementById('lb-img');
  const vid = document.getElementById('lb-video');
  const aud = document.getElementById('lb-audio');

  [img, vid, aud].forEach(el => { el.classList.add('hidden'); el.pause && el.pause(); });
  lbBuildInfo(e);

  if (e.type === 'image') {
    img.src = e.src; img.alt = e.title;
    img.classList.remove('hidden');
  } else if (e.type === 'video') {
    vid.src = e.src;
    vid.classList.remove('hidden');
    vid.play().catch(() => {});
  } else if (e.type === 'audio') {
    aud.src = e.src;
    aud.classList.remove('hidden');
    aud.play().catch(() => {});
  }

  document.getElementById('lb-title').textContent   = e.title !== e.name ? e.title : '';
  document.getElementById('lb-caption').textContent = e.caption || '';
  document.getElementById('lb-counter').textContent = `${lbIndex + 1} / ${ENTRIES.length}`;

  const dl = document.getElementById('lb-download');
  dl.href     = e.src;
  dl.download = e.name;

  // Update URL hash so the address bar is the shareable link
  history.replaceState(null, '', location.pathname + location.search + '#photo=' + encodeURIComponent(e.name));
}

function lbCopyLink() {
  navigator.clipboard.writeText(location.href).then(() => {
    const btn = document.getElementById('lb-copylink');
    const orig = btn.textContent;
    btn.textContent = '✓ Copied!';
    setTimeout(() => { btn.textContent = orig; }, 1800);
  }).catch(() => {
    // Fallback: select a temporary input
    const tmp = document.createElement('input');
    tmp.value = location.href;
    document.body.appendChild(tmp);
    tmp.select();
    document.execCommand('copy');
    document.body.removeChild(tmp);
  });
}

function lbKey(ev) {
  if (ev.key === 'Escape')       closeLightbox();
  else if (ev.key === 'ArrowLeft')  lbNav(-1);
  else if (ev.key === 'ArrowRight') lbNav(1);
}

// Restore lightbox from URL hash on page load
window.addEventListener('DOMContentLoaded', () => {
  const m = location.hash.match(/^#photo=(.+)$/);
  if (m) {
    const name = decodeURIComponent(m[1]);
    const idx  = ENTRIES.findIndex(e => e.name === name);
    if (idx >= 0) openLightbox(idx);
  }
});

// Album search filter + slideshow link (kept together so filter state feeds the link)
(function () {
  const input = document.getElementById('album-search');
  const link  = document.getElementById('ss-launch');

  function updateSsLink() {
    if (!link) return;
    const p = [];
    if (document.getElementById('ss-opt-shuffle')?.checked)    p.push('shuffle=1');
    if (document.getElementById('ss-opt-fullscreen')?.checked) p.push('fullscreen=1');
    if (input && input.value.trim()) {
      const visible = [...document.querySelectorAll('#album-grid .album-card')]
        .filter(c => c.style.display !== 'none')
        .map(c => c.dataset.rel)
        .filter(Boolean);
      if (visible.length) p.push('dirs=' + visible.map(encodeURIComponent).join(','));
    }
    link.href = link.dataset.base + (p.length ? '?' + p.join('&') : '');
  }

  if (input) {
    input.addEventListener('input', () => {
      const q = input.value.trim().toLowerCase();
      document.querySelectorAll('#album-grid .album-card').forEach(card => {
        const label = (card.querySelector('.album-label')?.textContent || '').toLowerCase();
        card.style.display = !q || label.includes(q) ? '' : 'none';
      });
      updateSsLink();
    });
  }

  ['ss-opt-shuffle', 'ss-opt-fullscreen'].forEach(id =>
    document.getElementById(id)?.addEventListener('change', updateSsLink)
  );
})();

// Touch swipe
(function () {
  let startX = null;
  const lb = document.getElementById('lightbox');
  if (!lb) return;
  lb.addEventListener('touchstart', e => { startX = e.changedTouches[0].clientX; }, { passive: true });
  lb.addEventListener('touchend', e => {
    if (startX === null) return;
    const dx = e.changedTouches[0].clientX - startX;
    if (Math.abs(dx) > 50) lbNav(dx < 0 ? 1 : -1);
    startX = null;
  }, { passive: true });
})();