// ── FAVORITES ─────────────────────────────────────────────────────────────────
let favorites = new Set(JSON.parse(localStorage.getItem('gridtv-favorites') || '[]'));

function saveFavorites() {
  localStorage.setItem('gridtv-favorites', JSON.stringify([...favorites]));
}

function toggleFavorite(chId, btn) {
  if (favorites.has(chId)) {
    favorites.delete(chId);
    btn.classList.remove('is-fav');
    btn.title = L.fav_add;
  } else {
    favorites.add(chId);
    btn.classList.add('is-fav');
    btn.title = L.fav_remove;
  }
  saveFavorites();
  renderAll();
}

function makeFavBtn(chId) {
  const btn = document.createElement('button');
  btn.className = 'fav-btn' + (favorites.has(chId) ? ' is-fav' : '');
  btn.title = favorites.has(chId) ? L.fav_remove : L.fav_add;
  btn.textContent = '★';
  btn.addEventListener('click', e => { e.stopPropagation(); toggleFavorite(chId, btn); });
  return btn;
}

function sortedChannels(list) {
  const favs = list.filter(ch => favorites.has(ch.id));
  const rest  = list.filter(ch => !favorites.has(ch.id));
  return { favs, rest };
}