const queryInput = document.getElementById('query');
const searchBtn = document.getElementById('searchBtn');
const searchTypeSelect = document.getElementById('searchType');
const existsFilterSelect = document.getElementById('existsFilter');
const results = document.getElementById('results');
const statusEl = document.getElementById('status');
const dialog = document.getElementById('albumDialog');
const dialogTitle = document.getElementById('dialogTitle');
const dialogArtist = document.getElementById('dialogArtist');
const trackList = document.getElementById('trackList');
const sendBtn = document.getElementById('sendBtn');
const cleanupToggle = document.getElementById('cleanupToggle');
const updateLibraryBtn = document.getElementById('updateLibraryBtn');
const updateFrontendBtn = document.getElementById('updateFrontendBtn');
const scanLibraryBtn = document.getElementById('scanLibraryBtn');
const playlistSource = document.getElementById('playlistSource');
const playlistValue = document.getElementById('playlistValue');
const importPlaylistBtn = document.getElementById('importPlaylistBtn');
const sendPlaylistBtn = document.getElementById('sendPlaylistBtn');
const playlistActions = document.getElementById('playlistActions');
const jobList = document.getElementById('jobList');

let selectedAlbum = null;
let sendContext = null;
let playlistTracks = [];
let jobs = [];
let lastSearch = { type: null, items: [] };

const CLEANUP_KEY = 'cleanupExtras';
cleanupToggle.checked = localStorage.getItem(CLEANUP_KEY) === 'true';
cleanupToggle.addEventListener('change', () => {
  localStorage.setItem(CLEANUP_KEY, String(cleanupToggle.checked));
});

function setStatus(text, isError = false) {
  statusEl.textContent = text;
  statusEl.style.color = isError ? 'var(--danger)' : 'var(--text)';
}

function formatDuration(ms) {
  const totalSec = Math.floor(ms / 1000);
  const min = Math.floor(totalSec / 60);
  const sec = totalSec % 60;
  return `${min}:${String(sec).padStart(2, '0')}`;
}

async function fetchJson(url, options = {}) {
  const response = await fetch(url, options);
  const data = await response.json();
  if (!response.ok) {
    throw new Error(data.error || `HTTP ${response.status}`);
  }
  return data;
}

function pill(exists) {
  return `<span class="pill ${exists ? 'exists' : 'missing'}">${exists ? 'Vorhanden' : 'Fehlt'}</span>`;
}

function createAlbumCard(album, preselectedTrackNames = []) {
  const card = document.createElement('article');
  card.className = 'album-card';
  card.innerHTML = `
    ${album.image ? `<img class="album-cover" src="${album.image}" alt="${album.name}" />` : '<div class="album-cover"></div>'}
    <div class="album-body">
      <h3>${album.name}</h3>
      <p>${album.artist}</p>
      <p>${album.totalTracks} Tracks - ${album.releaseDate || 'unbekannt'}</p>
      <p>${pill(Boolean(album.exists))}</p>
      <button type="button">Album auswaehlen</button>
    </div>
  `;
  card.querySelector('button').addEventListener('click', () =>
    openAlbumDialog(album.id, preselectedTrackNames, { albumName: album.name, artistName: album.artist })
  );
  return card;
}

function createTrackCard(track) {
  const card = document.createElement('article');
  card.className = 'album-card';
  card.innerHTML = `
    ${track.image ? `<img class="album-cover" src="${track.image}" alt="${track.albumName}" />` : '<div class="album-cover"></div>'}
    <div class="album-body">
      <h3>${track.trackName}</h3>
      <p>${track.artist}</p>
      <p>Album: ${track.albumName}</p>
      <p>${pill(Boolean(track.exists))}</p>
      <button type="button">Album fuer Track auswaehlen</button>
    </div>
  `;
  card.querySelector('button').addEventListener('click', () =>
    openAlbumDialog(track.albumId, [track.trackName], {
      albumName: track.albumName,
      artistName: track.albumArtist || track.artist
    })
  );
  return card;
}

function createArtistCard(artist) {
  const card = document.createElement('article');
  card.className = 'album-card';
  card.innerHTML = `
    ${artist.image ? `<img class="album-cover" src="${artist.image}" alt="${artist.name}" />` : '<div class="album-cover"></div>'}
    <div class="album-body">
      <h3>${artist.name}</h3>
      <p>${artist.followers || 0} Follower</p>
      <button type="button">Alben anzeigen</button>
    </div>
  `;
  card.querySelector('button').addEventListener('click', () => loadArtistAlbums(artist.id, artist.name));
  return card;
}

function createPlaylistTrackCard(track, idx) {
  const card = document.createElement('article');
  card.className = 'album-card';
  card.innerHTML = `
    ${track.image ? `<img class="album-cover" src="${track.image}" alt="${track.albumName}" />` : '<div class="album-cover"></div>'}
    <div class="album-body">
      <h3>${track.trackName}</h3>
      <p>${track.artist}</p>
      <p>Album: ${track.albumName}</p>
      <p>${pill(Boolean(track.exists))}</p>
      <label><input type="checkbox" data-playlist-idx="${idx}" ${track.selected ? 'checked' : ''}/> Auswaehlen</label>
    </div>
  `;
  return card;
}

function renderItems(type, items) {
  lastSearch = { type, items: Array.isArray(items) ? items : [] };
  results.innerHTML = '';
  const filtered = applyExistsFilter(lastSearch.items, type);
  if (!filtered.length) {
    results.innerHTML = '<p>Keine Treffer gefunden.</p>';
    return;
  }
  for (const item of filtered) {
    let card;
    if (type === 'track') card = createTrackCard(item);
    if (type === 'artist') card = createArtistCard(item);
    if (type === 'album') card = createAlbumCard(item);
    if (card) results.appendChild(card);
  }
}

function applyExistsFilter(items, type) {
  const mode = existsFilterSelect.value || 'all';
  if (mode === 'all') return items;
  if (type === 'artist') return items;

  return (items || []).filter((item) => {
    const exists = Boolean(item.exists);
    if (mode === 'exists') return exists;
    if (mode === 'missing') return !exists;
    return true;
  });
}

function updateDialogActionButton() {
  const rows = Array.from(trackList.querySelectorAll('input[type="checkbox"]'));
  const selected = rows.filter((x) => x.checked).map((x) => ({
    exists: x.dataset.exists === 'true'
  }));
  const add = selected.filter((x) => !x.exists).length;
  const keep = selected.filter((x) => x.exists).length;
  const remove = rows.filter((x) => !x.checked && x.dataset.exists === 'true').length;

  if (add > 0 && remove > 0) {
    sendBtn.textContent = `Anwenden (+${add} / -${remove})`;
  } else if (add > 0) {
    sendBtn.textContent = `Hinzufuegen (${add})`;
  } else if (remove > 0) {
    sendBtn.textContent = `Entfernen (${remove})`;
  } else if (keep > 0) {
    sendBtn.textContent = `Behalten (${keep})`;
  } else {
    sendBtn.textContent = 'An Lidarr senden';
  }
}

async function openAlbumDialog(albumId, preselectedTrackNames = [], context = null) {
  setStatus('Lade Albumdetails...');
  try {
    const album = await fetchJson(`/api/spotify/album/${albumId}`);
    selectedAlbum = album;
    sendContext = context;

    dialogTitle.textContent = album.name;
    dialogArtist.textContent = `Artist: ${album.artist}`;

    const preselected = new Set(preselectedTrackNames || []);
    trackList.innerHTML = '';
    for (const track of album.tracks) {
      const row = document.createElement('label');
      row.className = 'track-row';
      const isChecked = preselected.size > 0 ? preselected.has(track.name) : true;
      row.innerHTML = `
        <input type="checkbox" ${isChecked ? 'checked' : ''} data-track-name="${track.name.replace(/"/g, '&quot;')}" data-exists="${Boolean(track.exists)}" />
        <span>${track.trackNumber}. ${track.name}</span>
        <small>(${formatDuration(track.durationMs)})</small>
        ${pill(Boolean(track.exists))}
      `;
      const input = row.querySelector('input');
      input.addEventListener('change', updateDialogActionButton);
      trackList.appendChild(row);
    }

    updateDialogActionButton();
    dialog.showModal();
    setStatus('Album bereit. Auswahl pruefen und senden.');
  } catch (err) {
    setStatus(err.message, true);
  }
}

async function loadArtistAlbums(artistId, artistName) {
  setStatus(`Lade Alben von ${artistName}...`);
  try {
    const data = await fetchJson(`/api/spotify/artist/${artistId}/albums`);
    renderItems('album', data.albums || []);
    setStatus(`${data.albums.length} Alben von ${artistName} gefunden.`);
  } catch (err) {
    setStatus(err.message, true);
  }
}

async function searchSpotify() {
  const q = queryInput.value.trim();
  const type = searchTypeSelect.value;
  if (!q) return setStatus('Bitte Suchbegriff eingeben.', true);

  setStatus('Suche in Spotify...');
  results.innerHTML = '';
  try {
    const data = await fetchJson(`/api/spotify/search?q=${encodeURIComponent(q)}&type=${encodeURIComponent(type)}`);
    renderItems(type, data.items || []);
    setStatus(`${(data.items || []).length} Treffer gefunden (${type}).`);
  } catch (err) {
    setStatus(err.message, true);
  }
}

function addJob(job) {
  jobs.unshift(job);
  if (jobs.length > 30) jobs = jobs.slice(0, 30);
  renderJobs();
}

function renderJobs() {
  jobList.innerHTML = '';
  for (const job of jobs) {
    const row = document.createElement('div');
    row.className = 'job-row';
    row.textContent = `${job.label}: ${job.status}`;
    jobList.appendChild(row);
  }
}

async function pollCommand(commandId, label) {
  if (!commandId) return;
  const job = { label, status: 'queued', commandId };
  addJob(job);

  for (let i = 0; i < 60; i += 1) {
    try {
      const data = await fetchJson(`/api/lidarr/command/${commandId}`);
      job.status = data.status || 'unknown';
      renderJobs();
      if (['completed', 'failed', 'aborted'].includes(String(data.status || '').toLowerCase())) return;
    } catch (_err) {
      job.status = 'status-unbekannt';
      renderJobs();
      return;
    }
    await new Promise((r) => setTimeout(r, 3000));
  }
}

async function sendToLidarr(event) {
  event.preventDefault();
  if (!selectedAlbum) return setStatus('Kein Album ausgewaehlt.', true);

  const rows = Array.from(trackList.querySelectorAll('input[type="checkbox"]'));
  const trackStates = rows.map((input) => ({
    name: input.dataset.trackName,
    selected: input.checked,
    exists: input.dataset.exists === 'true'
  }));
  const selectedTrackNames = trackStates.filter((x) => x.selected).map((x) => x.name);

  setStatus('Sende Auswahl an Lidarr...');
  sendBtn.disabled = true;
  try {
    const data = await fetchJson('/api/lidarr/send-album', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        albumName: sendContext?.albumName || selectedAlbum.name,
        artistName: sendContext?.artistName || selectedAlbum.artist,
        selectedTrackNames,
        trackStates,
        cleanupExtras: cleanupToggle.checked
      })
    });

    setStatus(`Aktion gespeichert (+${data.trackActions.add} / -${data.trackActions.remove} / =${data.trackActions.keep}).`);
    dialog.close();
    pollCommand(data.commandId, `${selectedAlbum.name}`);
  } catch (err) {
    setStatus(`Fehler: ${err.message}`, true);
  } finally {
    sendBtn.disabled = false;
  }
}

async function scanLibrary() {
  scanLibraryBtn.disabled = true;
  setStatus('Scanne Lidarr Bibliothek...');
  try {
    const data = await fetchJson('/api/lidarr/library-scan', { method: 'POST' });
    setStatus(`Bibliothek gescannt (${data.trackCount} Tracks).`);
  } catch (err) {
    setStatus(`Scan fehlgeschlagen: ${err.message}`, true);
  } finally {
    scanLibraryBtn.disabled = false;
  }
}

async function updateLibrary() {
  setStatus('Starte Lidarr Bibliothek-Update...');
  updateLibraryBtn.disabled = true;
  try {
    const data = await fetchJson('/api/lidarr/update-library', { method: 'POST' });
    setStatus(`Bibliothek-Update gestartet (${data.commandNames.join(', ')}).`);
  } catch (err) {
    setStatus(`Fehler beim Bibliothek-Update: ${err.message}`, true);
  } finally {
    updateLibraryBtn.disabled = false;
  }
}

async function updateFrontendFromGit() {
  setStatus('Hole aktuelle Git-Daten...');
  updateFrontendBtn.disabled = true;
  try {
    const data = await fetchJson('/api/system/update-frontend', { method: 'POST' });
    if (data.updated) {
      setStatus(`Frontend aktualisiert (${data.before} -> ${data.after}). Seite wird neu geladen...`);
      setTimeout(() => window.location.reload(), 1200);
    } else {
      setStatus(`Bereits aktuell (${data.after}).`);
    }
  } catch (err) {
    setStatus(`Frontend-Update fehlgeschlagen: ${err.message}`, true);
  } finally {
    updateFrontendBtn.disabled = false;
  }
}

function renderPlaylist() {
  lastSearch = { type: 'playlist-track', items: playlistTracks.slice() };
  results.innerHTML = '';
  const filtered = applyExistsFilter(playlistTracks, 'track');
  if (!filtered.length) {
    results.innerHTML = '<p>Keine Playlist-Tracks gefunden.</p>';
    playlistActions.style.display = 'none';
    return;
  }
  filtered.forEach((track) => {
    const idx = playlistTracks.indexOf(track);
    const card = createPlaylistTrackCard(track, idx);
    const cb = card.querySelector('input[type="checkbox"]');
    cb.addEventListener('change', () => {
      playlistTracks[idx].selected = cb.checked;
    });
    results.appendChild(card);
  });
  playlistActions.style.display = 'block';
}

async function importPlaylist() {
  const source = playlistSource.value;
  const value = playlistValue.value.trim();
  if (!value) return setStatus('Bitte Playlist URL oder ID eingeben.', true);

  importPlaylistBtn.disabled = true;
  setStatus(`Importiere ${source}-Playlist...`);
  try {
    const data = await fetchJson('/api/import/playlist', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ source, value })
    });
    playlistTracks = (data.tracks || []).map((t) => ({ ...t, selected: true }));
    renderPlaylist();
    setStatus(`${playlistTracks.length} Tracks importiert.`);
  } catch (err) {
    setStatus(`Playlist-Import fehlgeschlagen: ${err.message}`, true);
  } finally {
    importPlaylistBtn.disabled = false;
  }
}

async function sendPlaylistSelection() {
  const selected = playlistTracks.filter((t) => t.selected);
  if (!selected.length) return setStatus('Keine Playlist-Tracks ausgewaehlt.', true);

  const groups = new Map();
  for (const track of selected) {
    const key = `${track.albumName}___${track.albumArtist}`;
    if (!groups.has(key)) {
      groups.set(key, {
        albumName: track.albumName,
        artistName: track.albumArtist,
        selectedTrackNames: [],
        trackStates: []
      });
    }
    const g = groups.get(key);
    g.selectedTrackNames.push(track.trackName);
    g.trackStates.push({ name: track.trackName, selected: true, exists: Boolean(track.exists) });
  }

  setStatus(`Sende ${groups.size} Alben aus Playlist an Lidarr...`);
  sendPlaylistBtn.disabled = true;
  try {
    for (const item of groups.values()) {
      const data = await fetchJson('/api/lidarr/send-album', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(item)
      });
      pollCommand(data.commandId, `${item.artistName} - ${item.albumName}`);
    }
    setStatus('Playlist-Auswahl wurde an Lidarr uebergeben.');
  } catch (err) {
    setStatus(`Fehler bei Playlist-Download: ${err.message}`, true);
  } finally {
    sendPlaylistBtn.disabled = false;
  }
}

searchBtn.addEventListener('click', searchSpotify);
queryInput.addEventListener('keydown', (event) => {
  if (event.key === 'Enter') searchSpotify();
});
sendBtn.addEventListener('click', sendToLidarr);
scanLibraryBtn.addEventListener('click', scanLibrary);
updateLibraryBtn.addEventListener('click', updateLibrary);
updateFrontendBtn.addEventListener('click', updateFrontendFromGit);
importPlaylistBtn.addEventListener('click', importPlaylist);
sendPlaylistBtn.addEventListener('click', sendPlaylistSelection);
existsFilterSelect.addEventListener('change', () => {
  if (lastSearch.type === 'playlist-track') {
    renderPlaylist();
    return;
  }
  if (lastSearch.type) {
    renderItems(lastSearch.type, lastSearch.items);
  }
});

renderJobs();