import { S } from '../state.js';
import { closeSidebar, switchNavMode } from '../ui/ui.js';
import { closeNowPlaying, closeNpMenu } from '../player/nowplaying.js';
import { loadSpotifyImporter } from './spotify.js';
import { loadSoundCloudImporter } from './soundcloud.js';
// Circular — safe (all calls happen inside function bodies)
import { loadHomeData, loadAlbumRow, loadArtists, loadAlbums, loadGenreDetail } from './home.js';
import { loadArtistDetail, loadArtistAllSongs, loadAlbumDetail, loadItunesAlbumDetail } from './detail.js';
import { loadPlaylists, loadPlaylistDetail, loadStarred, loadRandom } from './playlists.js';
import { loadNewReleases, loadRecommendations } from './discover.js';

// ─── NAVIGATION HISTORY ───
export function _navSave() {
  try { sessionStorage.setItem('ns_nav', JSON.stringify({stack: S._navStack, cursor: S._navCursor})); } catch {}
}

export function _navLoad() {
  try {
    const s = JSON.parse(sessionStorage.getItem('ns_nav') || 'null');
    if(s && Array.isArray(s.stack) && s.stack.length) {
      S._navStack = s.stack;
      S._navCursor = s.cursor;
      return true;
    }
  } catch {}
  return false;
}

export function closeHeaderSearch() {
  const overlay  = document.getElementById('header-search-overlay');
  const input    = document.getElementById('header-search-input');
  const clearBtn = document.getElementById('header-search-clear');
  if (overlay)  overlay.style.display  = 'none';
  if (input)    input.value            = '';
  if (clearBtn) clearBtn.style.display = 'none';
  clearTimeout(S._headerSearchTimer);
}

export function navigate(page, data=null) {
  closeHeaderSearch();
  document.querySelectorAll('.page').forEach(p => p.classList.remove('active'));
  document.querySelectorAll('.nav-item,.bnav-item').forEach(n => n.classList.remove('active','active-blue'));
  const cls = ['discover','new-releases','recommendations','spotify-importer'].includes(page) ? 'active-blue' : 'active';
  document.querySelectorAll(`[data-page="${page}"]`).forEach(el => el.classList.add(cls));
  const pageEl = document.getElementById(`page-${page}`);
  if(pageEl) { pageEl.classList.add('active'); document.getElementById('main-content').scrollTop = 0; }
  closeSidebar();
  if(['discover','new-releases','recommendations','random','spotify-importer'].includes(page)) switchNavMode('discover');
  else if(['home','artists','albums','starred','playlists'].includes(page)) switchNavMode('library');

  if(page==='home')    loadHomeData();
  if(page==='artists' && !document.getElementById('artists-grid').children.length) loadArtists();
  if(page==='albums'  && !document.getElementById('albums-grid').children.length)  loadAlbums();
  if(page==='starred')       loadStarred();
  if(page==='random')        loadRandom();
  if(page==='artist-detail'      && data) loadArtistDetail(data);
  if(page==='artist-all-songs'   && data) loadArtistAllSongs(data);
  if(page==='album-detail'       && data) loadAlbumDetail(data);
  if(page==='genre-detail'       && data) loadGenreDetail(data);
  if(page==='itunes-album-detail'&& data) loadItunesAlbumDetail(data);
  if(page==='new-releases')  loadNewReleases();
  if(page==='playlists')     loadPlaylists();
  if(page==='playlist-detail' && data) loadPlaylistDetail(data);
  if(page==='recommendations')  loadRecommendations();
  if(page==='spotify-importer') { loadSpotifyImporter(); loadSoundCloudImporter(); }
  if(page==='audiobooks') {
    import('./abs.js').then(m => {
      if (S.abs.currentLibraryId) m.loadAbsBooks(S.abs.currentLibraryId);
    });
  }
  if(page==='abs-book-detail' && data) {
    import('./abs.js').then(m => m.loadAbsBookDetail(data.id));
  }

  if(!S._navJumping) {
    S._navStack = S._navStack.slice(0, S._navCursor + 1);
    const safe = data ? JSON.parse(JSON.stringify(data)) : null;
    const last = S._navStack[S._navCursor];
    if(!last || last.page !== page || JSON.stringify(last.data) !== JSON.stringify(safe)) {
      S._navStack.push({ page, data: safe });
    }
    S._navCursor = S._navStack.length - 1;
    _navSave();
    try { history.pushState({ nsIdx: S._navCursor }, '', ''); } catch {}
  }
}

export function _navGoBack() {
  if(document.getElementById('np-sheet')?.classList.contains('open')) { closeNpMenu(); return; }
  if(S.npOpen) { closeNowPlaying(); return; }
  if(S._navCursor > 0) {
    S._navCursor--;
    const entry = S._navStack[S._navCursor];
    _navSave();
    S._navJumping = true;
    navigate(entry.page, entry.data);
    S._navJumping = false;
  }
  try { history.pushState({ nsIdx: S._navCursor }, '', ''); } catch {}
}