/**
 * OAuth Google / Twitch pour l'import des favoris et abonnements.
 *
 * - Google (YouTube) : scopes `youtube.readonly` (+ profil). Importe les
 *   abonnements (`subscriptions.list?mine=true`) et les favoris
 *   (`videos.list?myRating=like`).
 * - Twitch : scopes `user:read:follows user:read:subscriptions`. Importe les
 *   chaînes suivies (`/helix/users/follows?from_id=`). Twitch n'a pas de
 *   notion de "like" vidéo : seul l'import abonnements est proposé.
 *
 * Les tokens sont stockés en SQLite (instance locale / auto-hébergée).
 * Ne jamais logger access_token / refresh_token / client_secret.
 */

const GOOGLE_AUTH_URL = 'https://accounts.google.com/o/oauth2/v2/auth';
const GOOGLE_TOKEN_URL = 'https://oauth2.googleapis.com/token';
const TWITCH_AUTH_URL = 'https://id.twitch.tv/oauth2/authorize';
const TWITCH_TOKEN_URL = 'https://id.twitch.tv/oauth2/token';

const GOOGLE_SCOPES = [
  'openid',
  'https://www.googleapis.com/auth/userinfo.profile',
  'https://www.googleapis.com/auth/youtube.readonly',
  // Écriture Watch Later (playlistItems.insert/delete). Lecture seule
  // (abos, likes, WL) fonctionne sans lui ; le push exige un re-consentement.
  'https://www.googleapis.com/auth/youtube.force-ssl',
  // InnerTube authentifié (historique FEhistory, playlist WL) exige le scope
  // complet : avec readonly seul, YouTube répond 403 insufficientPermissions.
  // Les connexions existantes doivent se reconnecter pour l'obtenir.
  'https://www.googleapis.com/auth/youtube',
].join(' ');

/** Le jeton stocké permet-il l'écriture (push Watch Later) ? */
export function hasGoogleWriteScope(scopes) {
  const tokens = String(scopes || '').split(/\s+/).filter(Boolean);
  return tokens.some((t) => t === 'https://www.googleapis.com/auth/youtube.force-ssl' || t === 'https://www.googleapis.com/auth/youtube');
}

const TWITCH_SCOPES = ['user:read:follows', 'user:read:subscriptions'].join(' ');

// state -> { userId, provider, createdAt } (mémoire, 10 min).
const pendingStates = new Map();

function randomState() {
  try {
    const { randomBytes } = require('node:crypto');
    return randomBytes(16).toString('hex');
  } catch {}
  return `${Date.now().toString(36)}${Math.random().toString(36).slice(2)}`;
}

export function createOAuthState(userId, provider, purpose = 'link') {
  const state = randomState();
  pendingStates.set(state, {
    userId: userId == null ? null : String(userId),
    provider: String(provider),
    purpose: String(purpose || 'link'),
    createdAt: Date.now(),
  });
  // Purge opportuniste.
  try {
    const now = Date.now();
    for (const [k, v] of pendingStates) {
      if (now - v.createdAt > 10 * 60 * 1000) pendingStates.delete(k);
    }
  } catch {}
  return state;
}

export function consumeOAuthState(state) {
  const entry = pendingStates.get(String(state || ''));
  if (!entry) return null;
  pendingStates.delete(String(state));
  if (Date.now() - entry.createdAt > 10 * 60 * 1000) return null;
  return entry;
}

export function oauthStatus() {
  const googleId = String(process.env.GOOGLE_CLIENT_ID || '').trim();
  const googleSecret = String(process.env.GOOGLE_CLIENT_SECRET || '').trim();
  const twitchId = String(process.env.TWITCH_CLIENT_ID || '').trim();
  const twitchSecret = String(process.env.TWITCH_CLIENT_SECRET || '').trim();
  return {
    google: {
      configured: Boolean(googleId && googleSecret),
      missing: [...(!googleId ? ['GOOGLE_CLIENT_ID'] : []), ...(!googleSecret ? ['GOOGLE_CLIENT_SECRET'] : [])],
    },
    twitch: {
      configured: Boolean(twitchId && twitchSecret),
      missing: [...(!twitchId ? ['TWITCH_CLIENT_ID'] : []), ...(!twitchSecret ? ['TWITCH_CLIENT_SECRET'] : [])],
    },
  };
}

/** Base publique de l'app (pour la redirect_uri). Priorité au .env explicite. */
export function appBaseUrl(req) {
  const explicit = String(process.env.OAUTH_APP_BASE_URL || '').trim().replace(/\/+$/, '');
  if (explicit) return explicit;
  try {
    const proto = String(req?.headers?.['x-forwarded-proto'] || req?.protocol || 'http').split(',')[0].trim() || 'http';
    const host = String(req?.headers?.['x-forwarded-host'] || req?.headers?.host || req?.get?.('host') || '').trim();
    if (host) return `${proto}://${host}`;
  } catch {}
  return 'http://localhost:4200';
}

export function redirectUriFor(provider, req) {
  const p = String(provider);
  if (p === 'google') {
    const explicit = String(process.env.GOOGLE_REDIRECT_URI || '').trim();
    if (explicit) return explicit;
  }
  if (p === 'twitch') {
    const explicit = String(process.env.TWITCH_REDIRECT_URI || '').trim();
    if (explicit) return explicit;
  }
  return `${appBaseUrl(req).replace(/\/+$/, '')}/api/oauth/${p}/callback`;
}

export function buildAuthUrl(provider, state, req) {
  const p = String(provider);
  if (p === 'google') {
    const clientId = String(process.env.GOOGLE_CLIENT_ID || '').trim();
    if (!clientId) throw Object.assign(new Error('google_oauth_not_configured'), { status: 503 });
    const qs = new URLSearchParams({
      client_id: clientId,
      redirect_uri: redirectUriFor('google', req),
      response_type: 'code',
      scope: GOOGLE_SCOPES,
      access_type: 'offline',
      prompt: 'consent',
      state,
    });
    return `${GOOGLE_AUTH_URL}?${qs.toString()}`;
  }
  if (p === 'twitch') {
    const clientId = String(process.env.TWITCH_CLIENT_ID || '').trim();
    if (!clientId) throw Object.assign(new Error('twitch_oauth_not_configured'), { status: 503 });
    const qs = new URLSearchParams({
      client_id: clientId,
      redirect_uri: redirectUriFor('twitch', req),
      response_type: 'code',
      scope: TWITCH_SCOPES,
      state,
    });
    return `${TWITCH_AUTH_URL}?${qs.toString()}`;
  }
  throw Object.assign(new Error('invalid_oauth_provider'), { status: 400 });
}

async function postForm(url, params) {
  const body = new URLSearchParams(params);
  const resp = await fetch(url, {
    method: 'POST',
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    body: body.toString(),
  });
  const data = await resp.json().catch(() => ({}));
  if (!resp.ok) {
    const err = new Error(`oauth_token_failed_${resp.status}`);
    err.status = 502;
    err.details = data;
    throw err;
  }
  return data;
}

export async function exchangeCode(provider, code, req) {
  const p = String(provider);
  if (p === 'google') {
    const data = await postForm(GOOGLE_TOKEN_URL, {
      code: String(code),
      client_id: String(process.env.GOOGLE_CLIENT_ID || ''),
      client_secret: String(process.env.GOOGLE_CLIENT_SECRET || ''),
      redirect_uri: redirectUriFor('google', req),
      grant_type: 'authorization_code',
    });
    return {
      accessToken: data.access_token,
      refreshToken: data.refresh_token || null,
      expiresAt: data.expires_in ? Date.now() + Number(data.expires_in) * 1000 : null,
      scopes: data.scope || GOOGLE_SCOPES,
    };
  }
  if (p === 'twitch') {
    const data = await postForm(TWITCH_TOKEN_URL, {
      code: String(code),
      client_id: String(process.env.TWITCH_CLIENT_ID || ''),
      client_secret: String(process.env.TWITCH_CLIENT_SECRET || ''),
      redirect_uri: redirectUriFor('twitch', req),
      grant_type: 'authorization_code',
    });
    return {
      accessToken: data.access_token,
      refreshToken: data.refresh_token || null,
      expiresAt: data.expires_in ? Date.now() + Number(data.expires_in) * 1000 : null,
      scopes: Array.isArray(data.scope) ? data.scope.join(' ') : TWITCH_SCOPES,
    };
  }
  throw Object.assign(new Error('invalid_oauth_provider'), { status: 400 });
}

export async function refreshAccessToken(provider, refreshToken) {
  const p = String(provider);
  if (p === 'google') {
    const data = await postForm(GOOGLE_TOKEN_URL, {
      refresh_token: String(refreshToken),
      client_id: String(process.env.GOOGLE_CLIENT_ID || ''),
      client_secret: String(process.env.GOOGLE_CLIENT_SECRET || ''),
      grant_type: 'refresh_token',
    });
    return {
      accessToken: data.access_token,
      refreshToken: data.refresh_token || refreshToken,
      expiresAt: data.expires_in ? Date.now() + Number(data.expires_in) * 1000 : null,
    };
  }
  if (p === 'twitch') {
    const data = await postForm(TWITCH_TOKEN_URL, {
      refresh_token: String(refreshToken),
      client_id: String(process.env.TWITCH_CLIENT_ID || ''),
      client_secret: String(process.env.TWITCH_CLIENT_SECRET || ''),
      grant_type: 'refresh_token',
    });
    return {
      accessToken: data.access_token,
      refreshToken: data.refresh_token || refreshToken,
      expiresAt: data.expires_in ? Date.now() + Number(data.expires_in) * 1000 : null,
    };
  }
  throw Object.assign(new Error('invalid_oauth_provider'), { status: 400 });
}

async function getJson(url, accessToken, extraHeaders = {}) {
  const resp = await fetch(url, {
    headers: { Authorization: `Bearer ${accessToken}`, ...extraHeaders },
  });
  const data = await resp.json().catch(() => ({}));
  if (!resp.ok) {
    const err = new Error(`oauth_api_failed_${resp.status}`);
    err.status = resp.status === 401 ? 401 : 502;
    err.details = data;
    throw err;
  }
  return data;
}

// -------------------- Google (YouTube) --------------------

export async function fetchGoogleProfile(accessToken) {
  const data = await getJson('https://www.googleapis.com/oauth2/v2/userinfo', accessToken);
  return {
    id: String(data.id || ''),
    email: String(data.email || ''),
    verifiedEmail: data.verified_email !== false,
    displayName: String(data.name || data.email || 'Google'),
    avatarUrl: String(data.picture || ''),
  };
}

export async function fetchGoogleSubscriptions(accessToken, max = 1000) {
  const out = [];
  let total = 0;
  let pageToken = '';
  while (out.length < max) {
    const qs = new URLSearchParams({
      part: 'snippet',
      mine: 'true',
      maxResults: String(Math.min(50, max - out.length)),
      order: 'alphabetical',
    });
    if (pageToken) qs.set('pageToken', pageToken);
    const data = await getJson(`https://www.googleapis.com/youtube/v3/subscriptions?${qs.toString()}`, accessToken);
    if (!total && typeof data?.pageInfo?.totalResults === 'number') total = data.pageInfo.totalResults;
    for (const item of Array.isArray(data?.items) ? data.items : []) {
      const sn = item?.snippet || {};
      const channelId = sn?.resourceId?.channelId || '';
      if (!channelId) continue;
      out.push({
        provider: 'youtube',
        externalId: channelId,
        title: sn?.title || channelId,
        handle: null,
        avatarUrl: sn?.thumbnails?.default?.url || sn?.thumbnails?.medium?.url || null,
        url: `https://www.youtube.com/channel/${channelId}`,
      });
    }
    pageToken = data?.nextPageToken || '';
    if (!pageToken) break;
  }
  return { items: out, total: total || out.length };
}

export async function fetchGoogleLiked(accessToken, max = 500) {
  const out = [];
  let total = 0;
  let pageToken = '';
  while (out.length < max) {
    const qs = new URLSearchParams({
      part: 'snippet,contentDetails',
      myRating: 'like',
      maxResults: String(Math.min(50, max - out.length)),
    });
    if (pageToken) qs.set('pageToken', pageToken);
    const data = await getJson(`https://www.googleapis.com/youtube/v3/videos?${qs.toString()}`, accessToken);
    if (!total && typeof data?.pageInfo?.totalResults === 'number') total = data.pageInfo.totalResults;
    for (const item of Array.isArray(data?.items) ? data.items : []) {
      const id = item?.id || '';
      const sn = item?.snippet || {};
      if (!id) continue;
      out.push({
        provider: 'youtube',
        videoId: String(id),
        title: sn?.title || '',
        thumbnail: sn?.thumbnails?.medium?.url || sn?.thumbnails?.default?.url || '',
      });
    }
    pageToken = data?.nextPageToken || '';
    if (!pageToken) break;
  }
  return { items: out, total: total || out.length };
}

// -------------------- Google : Watch Later --------------------

async function googleApiGet(accessToken, path, params = {}) {
  const qs = new URLSearchParams();
  for (const [k, v] of Object.entries(params)) {
    if (v !== undefined && v !== null && v !== '') qs.set(k, String(v));
  }
  return getJson(`https://www.googleapis.com/youtube/v3/${path}?${qs.toString()}`, accessToken);
}

async function googleApiPost(accessToken, path, body) {
  const resp = await fetch(`https://www.googleapis.com/youtube/v3/${path}`, {
    method: 'POST',
    headers: { Authorization: `Bearer ${accessToken}`, 'Content-Type': 'application/json' },
    body: JSON.stringify(body || {}),
  });
  const data = await resp.json().catch(() => ({}));
  if (!resp.ok) {
    const err = new Error(`oauth_api_failed_${resp.status}`);
    err.status = resp.status === 401 ? 401 : resp.status === 403 ? 403 : 502;
    err.details = data;
    throw err;
  }
  return data;
}

/** Chaîne résolue par `mine=true` pour ce token (id + titre, pour comparer). */
export async function fetchMineChannel(accessToken) {
  const data = await googleApiGet(accessToken, 'channels', { part: 'id,snippet,contentDetails', mine: 'true' });
  const item = Array.isArray(data?.items) ? data.items[0] : null;
  if (!item) return { id: null, title: null, relatedKeys: [] };
  return {
    id: item.id || null,
    title: item.snippet?.title || null,
    relatedKeys: Object.keys(item?.contentDetails?.relatedPlaylists || {}),
  };
}

/** ID de la playlist "Regarder plus tard" du compte (lecture seule OK). */
export async function fetchGoogleWatchLaterId(accessToken) {
  const data = await googleApiGet(accessToken, 'channels', { part: 'contentDetails', mine: 'true' });
  const item = Array.isArray(data?.items) ? data.items[0] : null;
  if (!item) {
    throw Object.assign(new Error('youtube_no_channel'), {
      status: 502,
      hint: 'Ce compte Google n’a pas de chaîne YouTube : créez-en une sur youtube.com pour utiliser Regarder plus tard.',
    });
  }
  const id = item?.contentDetails?.relatedPlaylists?.watchLater || '';
  if (!id) {
    // Diagnostic sans PII : quelles playlists liées YouTube expose-t-il ?
    try {
      console.warn('[oauth] watchLater absent, relatedPlaylists =', Object.keys(item?.contentDetails?.relatedPlaylists || {}).join(',') || '(vide)');
    } catch {}
    throw Object.assign(new Error('watchlater_not_found'), {
      status: 502,
      hint: 'YouTube ne renvoie pas de playlist « Regarder plus tard » pour ce compte (compte de marque sans chaîne principale ?). Les abonnements et favoris restent importables.',
    });
  }
  return String(id);
}

async function fetchWatchLaterItems(accessToken, playlistId, max) {
  const out = [];
  let pageToken = '';
  while (out.length < max) {
    const data = await googleApiGet(accessToken, 'playlistItems', {
      part: 'snippet,contentDetails',
      playlistId,
      maxResults: Math.min(50, max - out.length),
      ...(pageToken ? { pageToken } : {}),
    });
    for (const item of Array.isArray(data?.items) ? data.items : []) {
      const vid = item?.contentDetails?.videoId || item?.snippet?.resourceId?.videoId || '';
      if (!vid) continue;
      const sn = item?.snippet || {};
      out.push({
        provider: 'youtube',
        videoId: String(vid),
        title: sn?.title || '',
        thumbnail: sn?.thumbnails?.medium?.url || sn?.thumbnails?.default?.url || '',
        playlistItemId: item?.id || null,
      });
    }
    pageToken = data?.nextPageToken || '';
    if (!pageToken) break;
  }
  return out;
}

/**
 * Contenu de "Regarder plus tard" via Data API (lecture seule OK).
 * 1) ID résolu via channels.list, 2) alias officiel "WL".
 * Le repli youtubei.js est géré par la route (jeton complet requis).
 */
export async function fetchGoogleWatchLater(accessToken, max = 50) {
  try {
    const playlistId = await fetchGoogleWatchLaterId(accessToken);
    return { playlistId, items: await fetchWatchLaterItems(accessToken, playlistId, max), via: 'api' };
  } catch (e) {
    if (e?.message !== 'watchlater_not_found' && e?.message !== 'youtube_no_channel') throw e;
  }
  return { playlistId: 'WL', items: await fetchWatchLaterItems(accessToken, 'WL', max), via: 'api-alias' };
}

/**
 * Ajoute une vidéo à "Regarder plus tard" (exige le scope force-ssl).
 * ID résolu, sinon alias "WL", sinon InnerTube.
 */
export async function pushGoogleWatchLater(accessToken, videoId, apiKey = '') {
  let playlistId = 'WL';
  try {
    playlistId = await fetchGoogleWatchLaterId(accessToken);
  } catch (e) {
    if (e?.message !== 'watchlater_not_found' && e?.message !== 'youtube_no_channel') throw e;
  }
  try {
    const data = await googleApiPost(accessToken, 'playlistItems?part=snippet', {
      snippet: {
        playlistId,
        resourceId: { kind: 'youtube#video', videoId: String(videoId) },
      },
    });
    return { playlistItemId: data?.id || null, via: playlistId === 'WL' ? 'api-alias' : 'api' };
  } catch (e) {
    if (e?.status === 401) throw e;
    await pushInnerTubeWatchLater(accessToken, apiKey, videoId);
    return { playlistItemId: null, via: 'innertube' };
  }
}

// -------------------- Historique YouTube via InnerTube authentifié --------------------
// L'API Data v3 n'expose pas l'historique : on passe par youtubei/v1/browse
// (browseId FEhistory) avec le Bearer OAuth de l'utilisateur — même mécanisme
// que SmartTube. Lecture seule, pas de scope supplémentaire.

function pickThumb(thumbnails) {
  const list = Array.isArray(thumbnails) ? thumbnails : [];
  let best = null;
  for (const t of list) {
    if (!t?.url) continue;
    if (!best || Number(t.width || 0) > Number(best.width || 0)) best = t;
  }
  return best?.url || '';
}

function runsText(runs) {
  try {
    return (Array.isArray(runs) ? runs : []).map((r) => r?.text || '').join('');
  } catch { return ''; }
}

function extractHistoryEntries(node, out) {
  if (!node || typeof node !== 'object') return;
  if (Array.isArray(node)) {
    for (const e of node) extractHistoryEntries(e, out);
    return;
  }
  if (node.videoRenderer?.videoId) {
    const vr = node.videoRenderer;
    out.push({
      provider: 'youtube',
      videoId: String(vr.videoId),
      title: runsText(vr.title?.runs) || String(vr.title?.simpleText || vr.videoId),
      thumbnail: pickThumb(vr.thumbnail?.thumbnails),
      watchedAt: new Date().toISOString(),
    });
    return;
  }
  for (const v of Object.values(node)) {
    if (v && typeof v === 'object') extractHistoryEntries(v, out);
  }
}

function findHistoryContinuation(data) {
  try {
    const tabs = data?.contents?.singleColumnBrowseResultsRenderer?.tabs || [];
    const stack = [...tabs];
    while (stack.length) {
      const n = stack.pop();
      if (!n || typeof n !== 'object') continue;
      if (Array.isArray(n)) { stack.push(...n); continue; }
      const token = n?.continuationItemRenderer?.continuationEndpoint?.continuationCommand?.token;
      if (token) return String(token);
      for (const v of Object.values(n)) {
        if (v && typeof v === 'object') stack.push(v);
      }
    }
  } catch {}
  return null;
}

/**
 * Appel youtubei/v1/* authentifié (Bearer OAuth utilisateur).
 * La clé YOUTUBE_API_KEY est souvent restreinte par referrer HTTP : l'appel
 * serveur (sans Referer) est alors rejeté en 403. On envoie un Referer
 * navigateur et on bascule sur la clé publique du client web en repli.
 */
const PUBLIC_INNERTUBE_KEY = 'AIzaSyAO_FJ2SlqU8Q4STEHLGCilw_Y9_11qcW8';

function innertubeKeys(apiKey) {
  const keys = [String(apiKey || '').trim(), PUBLIC_INNERTUBE_KEY].filter(Boolean);
  return [...new Set(keys)];
}

async function innertubePost(path, apiKey, accessToken, body, label = 'innertube') {
  const keys = innertubeKeys(apiKey);
  if (!keys.length) throw Object.assign(new Error('youtube_api_key_unavailable'), { status: 503 });
  let lastErr = null;
  for (const key of keys) {
    try {
      const resp = await fetch(`https://www.youtube.com/youtubei/v1/${path}?key=${encodeURIComponent(key)}&prettyPrint=false`, {
        method: 'POST',
        headers: {
          Authorization: `Bearer ${accessToken}`,
          'Content-Type': 'application/json',
          // Sans Referer/UA navigateur, les clés restreintes et l'anti-bot répondent 403.
          Referer: 'https://www.youtube.com/',
          Origin: 'https://www.youtube.com',
          'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36',
        },
        body: JSON.stringify(body),
        signal: AbortSignal.timeout(20000),
      });
      const data = await resp.json().catch(() => ({}));
      if (!resp.ok) {
        const err = new Error(`${label}_failed_${resp.status}`);
        err.status = resp.status === 401 ? 401 : resp.status;
        // Motif YouTube (sans PII) pour diagnostiquer : ex. rateLimitExceeded,
        // botGuard, authError... remonte jusqu'à l'UI.
        try {
          const e0 = data?.error?.errors?.[0] || {};
          err.ytReason = String(e0.reason || data?.error?.message || '').slice(0, 160) || undefined;
        } catch {}
        throw err;
      }
      return data;
    } catch (e) {
      lastErr = e;
      // 403 = clé rejetée (restriction referrer) ou IP filtrée : on essaie la clé suivante.
      // 401 = token invalide : inutile de réessayer.
      if (e?.status === 401) throw e;
      if (e?.status !== 403) throw e;
    }
  }
  throw lastErr || new Error(`${label}_failed`);
}

function innertubeContext() {
  // Version du client WEB alignée sur youtubei.js (dépendance du projet) :
  // une version inconnue/inventée est rejetée en 403 par l'anti-bot.
  return { client: { clientName: 'WEB', clientVersion: '2.20260623.01.00', hl: 'fr', gl: 'FR' } };
}

/** Boucle browse + continuations générique (FEhistory, WL, ...). */
async function innertubeBrowseAll(accessToken, apiKey, browseId, max, label) {
  const out = [];
  const seen = new Set();
  let continuation = null;
  let pages = 0;
  while (out.length < max && pages < 10) {
    pages++;
    const body = continuation
      ? { context: innertubeContext(), continuation }
      : { context: innertubeContext(), browseId };
    const data = await innertubePost('browse', apiKey, accessToken, body, label);
    const batch = [];
    const root = continuation
      ? (data?.onResponseReceivedActions || data?.continuationContents)
      : data;
    extractHistoryEntries(root, batch);
    for (const v of batch) {
      if (seen.has(v.videoId)) continue;
      seen.add(v.videoId);
      out.push(v);
      if (out.length >= max) break;
    }
    continuation = findHistoryContinuation(data);
    if (!continuation) break;
  }
  return { items: out.slice(0, max), hasMore: Boolean(continuation) };
}

let ytLibNoiseSilenced = false;
async function silenceYoutubeiNoise() {
  if (ytLibNoiseSilenced) return;
  ytLibNoiseSilenced = true;
  try {
    const { Log } = await import('youtubei.js');
    if (Log?.set_level && Log?.Level) Log.set_level(Log.Level.ERROR ?? 3);
  } catch {}
}

/**
 * Session youtubei.js authentifiée avec les tokens OAuth stockés
 * (même Bearer que l'app, mais contexte client officiel complet).
 */
async function getAuthedInnertube(conn, { pageId } = {}) {
  const accessToken = String(conn?.accessToken || '');
  const refreshToken = String(conn?.refreshToken || '');
  const targetPageId = String(pageId || conn?.ytPageId || '').trim() || null;
  if (!accessToken) throw Object.assign(new Error('oauth_not_connected'), { status: 404 });
  if (!refreshToken) {
    throw Object.assign(new Error('google_reconnect_required'), {
      status: 403,
      hint: 'Jeton sans refresh_token : déconnectez puis reconnectez Google (cochez toutes les cases du consentement).',
    });
  }
  await silenceYoutubeiNoise();
  const { Innertube } = await import('youtubei.js');
  // targetPageId = chaîne/brand secondaire : on_behalf_of_user fait envoyer
  // X-Goog-PageId par youtubei.js (sélecteur de chaîne façon SmartTube).
  const innertube = await Innertube.create({
    lang: 'fr',
    location: 'FR',
    ...(targetPageId ? { on_behalf_of_user: targetPageId } : {}),
  });
  const expiry = Number(conn?.expiresAt || 0);
  await innertube.session.oauth.init({
    access_token: accessToken,
    refresh_token: refreshToken,
    expiry_date: new Date(expiry > 0 ? expiry : Date.now() + 3600_000).toISOString(),
    client: {
      client_id: String(process.env.GOOGLE_CLIENT_ID || ''),
      client_secret: String(process.env.GOOGLE_CLIENT_SECRET || ''),
    },
  });
  // oauth.init n'active pas logged_in tout seul (vérifié) : sans lui le
  // Bearer n'est jamais joint aux requêtes InnerTube ("You must be signed in").
  innertube.session.logged_in = true;
  return innertube;
}

/** Détail d'erreur YouTube exposable (clé/token masqués, 500 car. max). */
function libErrorDetail(e) {
  try {
    // youtubei.js met le corps de réponse dans e.info (JSON d'erreur Google).
    let raw = '';
    if (e?.info && typeof e.info === 'object') {
      try { raw = JSON.stringify(e.info); } catch { raw = String(e.info); }
    } else if (typeof e?.info === 'string') {
      raw = e.info;
    }
    const combined = [raw, String(e?.message || '')].filter(Boolean).join(' | ');
    // Extrait le motif Google s'il existe : {"error":{"errors":[{"reason":"X"}]}}.
    let reason = '';
    try {
      const parsed = JSON.parse(raw);
      const first = parsed?.error?.errors?.[0];
      if (first?.reason) reason = `reason=${first.reason}; msg=${String(first.message || parsed?.error?.message || '').slice(0, 200)}`;
    } catch {}
    const out = (reason || combined)
      .replace(/key=[^&\s]*/gi, 'key=[redacted]')
      .replace(/Bearer\s+[A-Za-z0-9._~-]+/gi, 'Bearer [redacted]')
      .slice(0, 500);
    return out || undefined;
  } catch { return undefined; }
}

function throwLibHistoryError(e, prefix) {
  if (e?.status === 404 || e?.status === 403 || e?.status === 401) throw e;
  const msg = String(e?.message || '');
  if (/reconnect/i.test(msg) || e?.message === 'google_reconnect_required') throw e;
  // youtubei.js encode le statut HTTP dans le message ("...status code 401").
  const m = /status code (\d{3})/.exec(msg);
  const status = m ? Number(m[1]) : e?.status;
  const err = new Error(`${prefix}_failed_${status || 'error'}`);
  err.status = status === 401 ? 401 : 502;
  const detail = libErrorDetail(e);
  if (detail) err.detail = detail;
  if (e?.ytReason) err.ytReason = e.ytReason;
  throw err;
}

/** Node History/Playlist (Video, LockupView, PlaylistVideo...) -> entrée. */
function mapHistoryNode(node, mapVideoNode) {
  if (!node || typeof node !== 'object') return null;
  if (String(node.type || '') === 'PlaylistVideo') {
    const id = node.video_id ? String(node.video_id) : null;
    const title = node.title?.text ?? (typeof node.title === 'string' ? node.title : '');
    if (!id || !title) return null;
    const thumbs = Array.isArray(node.thumbnails) ? node.thumbnails.filter((t) => t?.url) : [];
    return {
      provider: 'youtube',
      videoId: id,
      title: String(title),
      thumbnail: thumbs.length ? thumbs[thumbs.length - 1].url : '',
      watchedAt: new Date().toISOString(),
    };
  }
  const mapped = mapVideoNode(node);
  if (!mapped?.id) return null;
  return {
    provider: 'youtube',
    videoId: mapped.id,
    title: mapped.title || mapped.id,
    thumbnail: mapped.thumbnail || '',
    watchedAt: new Date().toISOString(),
  };
}

function textOf(t) {
  if (!t) return '';
  if (typeof t === 'string') return t;
  if (Array.isArray(t?.runs)) return t.runs.map((r) => r?.text || '').join('');
  return String(t?.simpleText || '');
}

/**
 * Diagnostic InnerTube authentifié : teste plusieurs endpoints et rapporte
 * pour chacun ok/count ou le motif YouTube. But : isoler un rejet global
 * du compte d'un problème spécifique à l'historique.
 */
export async function diagnoseInnertube(conn) {
  const out = {};
  let innertube = null;
  try {
    innertube = await getAuthedInnertube(conn);
    out.session = { ok: true };
  } catch (e) {
    out.session = { ok: false, reason: String(e?.message || e).slice(0, 200) };
    return out;
  }
  const probe = async (name, fn) => {
    try {
      const r = await fn();
      out[name] = { ok: true, ...r };
    } catch (e) {
      out[name] = { ok: false, reason: libErrorDetail(e) };
    }
  };
  await probe('subscriptionsFeed', async () => {
    const feed = await innertube.getSubscriptionsFeed();
    return { count: Array.isArray(feed?.contents) ? feed.contents.length : 0 };
  });
  await probe('library', async () => {
    await innertube.getLibrary();
    return {};
  });
  await probe('accountMenu', async () => {
    const data = await innertube.session.actions.execute('/account/account_menu', {});
    const blob = JSON.stringify(data?.data || data || '').slice(0, 200);
    return { sample: blob.slice(0, 120) };
  });
  await probe('history', async () => {
    const feed = await innertube.getHistory();
    const n = Array.isArray(feed?.sections) ? feed.sections.reduce((a, s) => a + (s?.contents?.length || 0), 0) : 0;
    return { count: n };
  });
  return out;
}

/**
 * Chaînes YouTube du compte (sélecteur façon SmartTube) via account_menu.
 * La chaîne par défaut peut être une coquille vide (relatedPlaylists sans
 * watchLater/history) alors que l'activité est sur une chaîne secondaire.
 */
export async function fetchAccountChannels(conn) {
  try {
    const innertube = await getAuthedInnertube(conn);
    const data = await innertube.session.actions.execute('/account/account_menu', {});
    const found = new Map();
    const visit = (node, depth = 0) => {
      if (!node || typeof node !== 'object' || depth > 12) return;
      if (Array.isArray(node)) {
        for (const e of node) visit(e, depth + 1);
        return;
      }
      // accountItem : nom + avatar (+ handle/canal à proximité).
      const name = textOf(node.accountName).trim();
      if (name) {
        const blob = JSON.stringify(node).slice(0, 4000);
        const ch = /UC[A-Za-z0-9_-]{20,}/.exec(blob)?.[0] || '';
        const handle = /@[A-Za-z0-9._-]{3,}/.exec(textOf(node.accountByline) + ' ' + blob)?.[0] || '';
        const key = ch || name.toLowerCase();
        if (!found.has(key)) {
          found.set(key, {
            channelId: ch || null,
            title: name,
            handle: handle || null,
            selected: Boolean(node.isSelected || node.isDefault),
          });
        }
      }
      for (const v of Object.values(node)) {
        if (v && typeof v === 'object') visit(v, depth + 1);
      }
    };
    visit(data?.data || data);
    return { channels: [...found.values()].slice(0, 10) };
  } catch (e) {
    throwLibHistoryError(e, 'yt_channels');
    throw e;
  }
}

/**
 * Historique YouTube via youtubei.js authentifié (getHistory + continuations).
 * `conn` = { accessToken, refreshToken, expiresAt, ytPageId? } (jeton déjà rafraîchi).
 */
export async function fetchInnerTubeHistory(conn, max = 200) {
  try {
    const { mapVideoNode } = await import('./providers/youtube-innertube.mjs');
    const innertube = await getAuthedInnertube(conn);
    const out = [];
    const seen = new Set();
    let feed = await innertube.getHistory();
    let guard = 0;
    while (feed && out.length < max && guard < 10) {
      guard++;
      const sections = Array.isArray(feed.sections) ? feed.sections : [];
      for (const section of sections) {
        const contents = Array.isArray(section?.contents) ? section.contents : [];
        for (const node of contents) {
          const v = mapHistoryNode(node, mapVideoNode);
          if (!v || seen.has(v.videoId)) continue;
          seen.add(v.videoId);
          out.push(v);
          if (out.length >= max) break;
        }
        if (out.length >= max) break;
      }
      if (out.length >= max) break;
      if (feed.has_continuation) feed = await feed.getContinuation();
      else break;
    }
    return { items: out.slice(0, max), hasMore: Boolean(feed?.has_continuation) };
  } catch (e) {
    throwLibHistoryError(e, 'innertube_history');
    throw e;
  }
}

/**
 * "Regarder plus tard" via youtubei.js authentifié (getPlaylist WL + continuations).
 */
export async function fetchInnerTubeWatchLaterViaLib(conn, max = 100) {
  try {
    const { mapVideoNode } = await import('./providers/youtube-innertube.mjs');
    const innertube = await getAuthedInnertube(conn);
    const out = [];
    const seen = new Set();
    let feed = await innertube.getPlaylist('WL');
    let guard = 0;
    while (feed && out.length < max && guard < 10) {
      guard++;
      const items = Array.isArray(feed.items) ? feed.items : [];
      for (const node of items) {
        const v = mapHistoryNode(node, mapVideoNode);
        if (!v || seen.has(v.videoId)) continue;
        seen.add(v.videoId);
        out.push(v);
        if (out.length >= max) break;
      }
      if (out.length >= max) break;
      if (feed.has_continuation) feed = await feed.getContinuation();
      else break;
    }
    return { items: out.slice(0, max), hasMore: Boolean(feed?.has_continuation), via: 'innertube' };
  } catch (e) {
    throwLibHistoryError(e, 'innertube_watchlater');
    throw e;
  }
}

/**
 * "Regarder plus tard" via InnerTube (browseId WL logique) : repli quand
 * l'API Data ne renvoie pas d'ID (comptes de marque...). Pas d'ID requis.
 */
export async function fetchInnerTubeWatchLater(accessToken, apiKey, max = 100) {
  try {
    const { items, hasMore } = await innertubeBrowseAll(accessToken, apiKey, 'WL', max, 'innertube_watchlater');
    return { items, hasMore, via: 'innertube' };
  } catch (e) {
    if (e?.message?.startsWith('innertube_watchlater_failed_')) throw e;
    const err = new Error(`innertube_watchlater_failed_${e?.status || 'error'}`);
    err.status = e?.status === 401 ? 401 : 502;
    throw err;
  }
}

/** Ajout à "Regarder plus tard" via InnerTube (playlistId logique WL). */
export async function pushInnerTubeWatchLater(accessToken, apiKey, videoId) {
  const data = await innertubePost('browse/editPlaylist', apiKey, accessToken, {
    context: innertubeContext(),
    actions: [{ action: 'ACTION_ADD_VIDEO', addedVideoId: String(videoId), playlistId: 'WL' }],
  }, 'innertube_watchlater_push');
  if (data?.status && String(data.status).toUpperCase() === 'FAIL') {
    throw Object.assign(new Error('innertube_watchlater_push_rejected'), { status: 502 });
  }
  return { ok: true };
}

// -------------------- Twitch --------------------

function twitchClientId() {
  return String(process.env.TWITCH_CLIENT_ID || '').trim();
}

export async function fetchTwitchProfile(accessToken) {
  const data = await getJson('https://api.twitch.tv/helix/users', accessToken, { 'Client-Id': twitchClientId() });
  const u = Array.isArray(data?.data) ? data.data[0] : null;
  if (!u) throw Object.assign(new Error('twitch_profile_failed'), { status: 502 });
  return {
    id: String(u.id || ''),
    displayName: String(u.display_name || u.login || 'Twitch'),
    avatarUrl: String(u.profile_image_url || ''),
    login: String(u.login || ''),
  };
}

export async function fetchTwitchFollows(accessToken, twitchUserId, max = 100) {
  const out = [];
  let cursor = '';
  while (out.length < max) {
    const qs = new URLSearchParams({
      from_id: String(twitchUserId),
      first: String(Math.min(100, max - out.length)),
    });
    if (cursor) qs.set('after', cursor);
    const data = await getJson(`https://api.twitch.tv/helix/users/follows?${qs.toString()}`, accessToken, {
      'Client-Id': twitchClientId(),
    });
    const list = Array.isArray(data?.data) ? data.data : [];
    // Enrichit les logins via /helix/users?id= (display_name + avatar).
    const ids = list.map((f) => f?.to_id).filter(Boolean).slice(0, 100);
    let usersById = new Map();
    if (ids.length) {
      try {
        const uqs = new URLSearchParams();
        ids.forEach((id) => uqs.append('id', String(id)));
        const udata = await getJson(`https://api.twitch.tv/helix/users?${uqs.toString()}`, accessToken, {
          'Client-Id': twitchClientId(),
        });
        for (const u of Array.isArray(udata?.data) ? udata.data : []) {
          usersById.set(String(u.id), u);
        }
      } catch {}
    }
    for (const f of list) {
      const toId = String(f?.to_id || '');
      if (!toId) continue;
      const u = usersById.get(toId);
      const login = String(u?.login || f?.to_name || '');
      out.push({
        provider: 'twitch',
        externalId: login || toId,
        twitchUserId: toId,
        title: String(u?.display_name || f?.to_name || login || toId),
        handle: login || null,
        avatarUrl: String(u?.profile_image_url || ''),
        url: login ? `https://www.twitch.tv/${login}` : '',
      });
    }
    cursor = data?.pagination?.cursor || '';
    if (!cursor || !list.length) break;
  }
  return out;
}