FabledCurator/extension/background/background.js

/**
 * Background script — message router + Discord token capture (webRequest).
 * Direct port of GS background.js; api.js client points at FC instead of GS.
 *
 * pixiv's PKCE OAuth flow lived here until FC retired pixiv (milestone #406).
 * It was removed together with pixiv's host permissions rather than left
 * behind: a webRequest listener on a host the manifest no longer grants is at
 * best dead and at worst a startup failure for the whole background script.
 */

let discordToken = null;
let discordTokenCapturedAt = null;

let initialized = false;

async function ensureInitialized() {
  if (initialized) return;
  await api.init();
  await loadDiscordToken();
  await forgetRetiredPixivToken();
  initialized = true;
}

// A browser that authenticated pixiv before the retirement still holds a live
// OAuth refresh token in extension storage. Nothing reads it any more, and a
// credential for a service FC no longer uses is a liability with no benefit
// (the same reasoning as the server-side cleanup, issue #3980). Removing keys
// that are absent is a no-op, so this is safe on every startup.
async function forgetRetiredPixivToken() {
  await browser.storage.local.remove(['pixivRefreshToken', 'pixivTokenCapturedAt']);
}

browser.runtime.onInstalled.addListener(() => ensureInitialized());
browser.runtime.onStartup.addListener(() => ensureInitialized());
ensureInitialized().catch(e => console.error('init failed:', e));

// ---- Extension self-update check (#1489) ----
// Installed per-instance from the operator's FC host, so Firefox's static
// update_url can't apply (each instance has a different host). Instead ask the
// configured backend for the latest published version and nudge the operator to
// reinstall the freshly-signed XPI — surfaced as a popup banner (on demand) and
// a toolbar badge (daily). /api/extension/manifest is public and returns
// {version, latest_url, sha256} plus an OPTIONAL {channel} naming which channel
// that instance serves ("dev"/"main", #3113); the XPI is served from the web
// root (not /api).
//
// The channel IS the instance: Firefox's static update_url cannot apply here
// because every FC install is a different host, so the extension asks its
// configured backend — which means switching channel is repointing apiUrl in
// options and reinstalling from that host. There is no separate channel
// setting to build, and building one would contradict each server build
// shipping its own extension.

function versionIsNewer(candidate, current) {
  // Dotted numeric compare so 1.0.10 > 1.0.9 (a plain string compare wouldn't).
  const a = String(candidate).split('.').map(n => parseInt(n, 10) || 0);
  const b = String(current).split('.').map(n => parseInt(n, 10) || 0);
  for (let i = 0; i < Math.max(a.length, b.length); i++) {
    if ((a[i] || 0) !== (b[i] || 0)) return (a[i] || 0) > (b[i] || 0);
  }
  return false;
}

async function checkForUpdateInfo() {
  await ensureInitialized();
  if (!api.isConfigured()) return { updateAvailable: false, configured: false };
  let info;
  try {
    info = await api.getExtensionManifest();
  } catch (e) {
    return { updateAvailable: false, error: e.message };
  }
  const currentVersion = browser.runtime.getManifest().version;
  const latestVersion = info && info.version ? info.version : null;
  // Which channel the configured instance serves — reported ALONGSIDE the
  // version, never folded into it. A `-dev` suffix would have to survive
  // versionIsNewer's parseInt above, and it wouldn't: the segment would read
  // as 0 and every dev build would compare equal to every other.
  //
  // null is a normal answer, not a failure — an instance built before the
  // field existed, or one built locally with no channel declared. Nothing
  // below branches on it except the label.
  const channel = info && info.channel ? info.channel : null;
  // latest_url is served from the web root, not the JSON API.
  const base = api.webRoot();
  return {
    updateAvailable: !!latestVersion && versionIsNewer(latestVersion, currentVersion),
    currentVersion,
    latestVersion,
    channel,
    // Where the Update button sends the operator: FC's own install card, not
    // the XPI. Firefox refuses an add-on install whose navigation an extension
    // started (tabs.create on the .xpi dies with NS_ERROR_FAILURE — operator-
    // flagged 2026-09-25); it accepts one from a user click on a web page,
    // which is exactly what the card's Install button is.
    installPageUrl: base ? `${base}/subscriptions?tab=settings` : null,
  };
}

async function refreshUpdateBadge() {
  let r;
  try { r = await checkForUpdateInfo(); } catch { return; }
  try {
    await browser.action.setBadgeText({ text: r.updateAvailable ? '↑' : '' });
    if (r.updateAvailable) {
      await browser.action.setBadgeBackgroundColor({ color: '#F4BA7A' });
      // Channel first, version second, and the channel dropped entirely when
      // the instance doesn't report one — so the tooltip reads exactly as it
      // did before the field existed rather than saying "(unknown ...)".
      const label = r.channel ? `${r.channel} v${r.latestVersion}` : `v${r.latestVersion}`;
      await browser.action.setTitle({ title: `FabledCurator — update available (${label})` });
    } else {
      await browser.action.setTitle({ title: 'FabledCurator' });
    }
  } catch { /* action API unavailable — non-fatal */ }
}

// Daily proactive check (needs the "alarms" permission). create() is idempotent
// by name, so re-running it on each event-page load is safe.
browser.alarms.create('fc-update-check', { periodInMinutes: 24 * 60, delayInMinutes: 1 });
browser.alarms.onAlarm.addListener((alarm) => {
  if (alarm.name === 'fc-update-check') refreshUpdateBadge();
});
browser.runtime.onStartup.addListener(() => refreshUpdateBadge());
browser.runtime.onInstalled.addListener(() => refreshUpdateBadge());

// ---- Discord token capture via webRequest ----

browser.webRequest.onBeforeSendHeaders.addListener(
  (details) => {
    const auth = details.requestHeaders?.find(h => h.name.toLowerCase() === 'authorization');
    if (auth?.value && auth.value !== discordToken) {
      saveDiscordToken(auth.value);
    }
  },
  // ptb/canary are Discord's beta clients; their API calls carry the same token.
  { urls: ['https://discord.com/api/*', 'https://*.discord.com/api/*'] },
  ['requestHeaders'],
);

async function loadDiscordToken() {
  const s = await browser.storage.local.get(['discordToken', 'discordTokenCapturedAt']);
  discordToken = s.discordToken || null;
  discordTokenCapturedAt = s.discordTokenCapturedAt || null;
}

async function saveDiscordToken(token) {
  discordToken = token;
  discordTokenCapturedAt = new Date().toISOString();
  await browser.storage.local.set({ discordToken: token, discordTokenCapturedAt });
}

// Extract → verify → upload one cookie-auth platform. Returns a structured
// outcome so the two callers (EXPORT_COOKIES single, EXPORT_ALL_COOKIES) shape
// their own response + skip semantics. Verifies the captured cookies are
// actually live BEFORE uploading, so a confirmed-stale session doesn't overwrite
// good FC-side credentials; platforms with no verify config (v.ok === null) fall
// through to upload.
async function exportPlatformCookies(key) {
  const cookies = await extractCookiesForPlatform(key);
  if (cookies.length === 0) return { status: 'empty' };
  const v = await verifyCookiesForPlatform(key);
  if (v.ok === false) return { status: 'stale', reason: v.reason, cookieCount: cookies.length };
  await api.uploadCredentials(key, 'cookies', toNetscapeFormat(cookies));
  return { status: 'ok', cookieCount: cookies.length, verified: v.ok === true };
}

// ---- Message router ----

browser.runtime.onMessage.addListener(async (msg) => {
  await ensureInitialized();
  switch (msg.type) {
    case 'GET_CONFIG':
      return { apiUrl: api.baseUrl, apiKey: api.apiKey };

    case 'TEST_CONNECTION':
      try {
        await api.testConnection();
        return { connected: true };
      } catch (e) {
        return { connected: false, error: e.message };
      }

    case 'GET_PLATFORM_STATUS': {
      const status = {};
      for (const key of Object.keys(PLATFORMS)) {
        if (PLATFORMS[key].authType === 'cookies') {
          status[key] = { hasCookies: false, cookieCount: 0 };
          try {
            const n = await getCookieCount(key);
            status[key] = { hasCookies: n > 0, cookieCount: n };
          } catch (e) {
            status[key] = { error: e.message };
          }
        } else if (key === 'discord') {
          status[key] = { hasToken: !!discordToken, capturedAt: discordTokenCapturedAt };
        } else {
          status[key] = {};
        }
      }
      return status;
    }

    case 'EXPORT_COOKIES': {
      const key = msg.platform;
      const platform = PLATFORMS[key];
      if (!platform) return { error: `Unknown platform: ${key}` };
      try {
        if (platform.authType === 'cookies') {
          const r = await exportPlatformCookies(key);
          if (r.status === 'empty') return { error: 'No cookies found — log in first.' };
          if (r.status === 'stale') {
            return {
              error: `Captured ${r.cookieCount} ${platform.name} cookies but they don't appear authenticated (${r.reason}). Log in again in this browser, then retry.`,
            };
          }
          return { success: true, cookieCount: r.cookieCount, verified: r.verified };
        }
        if (key === 'discord') {
          if (!discordToken) return { error: 'Open discord.com to capture a token first.' };
          await api.uploadCredentials('discord', 'token', discordToken);
          // Then have FC try it against a Discord source, so a token Discord
          // has already revoked shows up here rather than at the next check.
          // A failed verify never undoes the upload: valid=null means FC could
          // not test (no Discord source yet), not that the token is bad.
          let verify = null;
          try {
            verify = await api.verifyCredential('discord');
          } catch (e) {
            verify = { valid: null, reason: e.message };
          }
          return { success: true, verify };
        }
        return { error: 'Unsupported platform.' };
      } catch (e) {
        return { error: e.message };
      }
    }

    case 'EXPORT_ALL_COOKIES': {
      const results = {};
      for (const key of Object.keys(PLATFORMS)) {
        if (PLATFORMS[key].authType !== 'cookies') {
          results[key] = { skipped: true };
          continue;
        }
        try {
          const r = await exportPlatformCookies(key);
          if (r.status === 'empty') results[key] = { skipped: true, reason: 'no cookies' };
          else if (r.status === 'stale') results[key] = { error: `verify failed: ${r.reason}` };
          else results[key] = { success: true, cookieCount: r.cookieCount, verified: r.verified };
        } catch (e) {
          results[key] = { error: e.message };
        }
      }
      return results;
    }

    case 'LIST_SOURCES':
      try {
        return { sources: await api.listSources() };
      } catch (e) {
        return { error: e.message };
      }

    case 'CHECK_SOURCE':
      try {
        return await api.triggerSourceCheck(msg.sourceId);
      } catch (e) {
        return { error: e.message };
      }

    case 'ADD_AS_SOURCE':
      try {
        return await api.quickAddSource(msg.url, {
          artistId: msg.artistId ?? null,
          artistName: msg.artistName ?? null,
          usePlatformName: msg.usePlatformName === true,
        });
      } catch (e) {
        return { error: e.message };
      }

    case 'SEARCH_ARTISTS':
      try {
        return { artists: await api.searchArtists(msg.q || '') };
      } catch (e) {
        return { error: e.message };
      }

    case 'PROBE_SOURCE':
      try {
        return await api.probeSource(msg.url, { names: msg.names === true });
      } catch (e) {
        return { error: e.message };
      }

    case 'OPEN_ARTIST_PAGE': {
      // The SPA artist route (/artist/:slug) is served from the web root, not
      // the JSON API — see api.webRoot().
      const base = api.webRoot();
      const slug = encodeURIComponent(msg.slug || '');
      if (!base || !slug) return { error: 'apiUrl or slug missing' };
      try {
        await browser.tabs.create({ url: `${base}/artist/${slug}` });
        return { success: true };
      } catch (e) {
        return { error: e.message };
      }
    }

    case 'CHECK_UPDATE':
      return await checkForUpdateInfo();

    default:
      return { error: `Unknown message type: ${msg.type}` };
  }
});