import type express from 'express';
import type { Plugin, PluginContext } from '../../core/plugin.js';
import { sseBroadcast } from '../../core/sse.js';
import fs from 'node:fs';
import path from 'node:path';
import { lookupGame, enrichGames, type IgdbGameInfo } from './igdb.js';

// ── Types ──

interface SteamGame {
  appid: number;
  name: string;
  playtime_forever: number; // minutes
  img_icon_url: string;
  igdb?: IgdbGameInfo;
}

interface SteamUser {
  steamId: string;
  personaName: string;
  avatarUrl: string;
  profileUrl: string;
  games: SteamGame[];
  lastUpdated: string; // ISO date
}

interface GameLibraryData {
  users: Record<string, SteamUser>; // keyed by steamId
}

// ── Constants ──

const STEAM_API_KEY = process.env.STEAM_API_KEY || '2481D43449821AA4FF66502A9166DF32';

// ── Data Persistence ──

function getDataPath(ctx: PluginContext): string {
  return `${ctx.dataDir}/game-library.json`;
}

function loadData(ctx: PluginContext): GameLibraryData {
  try {
    const raw = fs.readFileSync(getDataPath(ctx), 'utf-8');
    return JSON.parse(raw) as GameLibraryData;
  } catch {
    const empty: GameLibraryData = { users: {} };
    saveData(ctx, empty);
    return empty;
  }
}

function saveData(ctx: PluginContext, data: GameLibraryData): void {
  try {
    const dir = path.dirname(getDataPath(ctx));
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir, { recursive: true });
    }
    fs.writeFileSync(getDataPath(ctx), JSON.stringify(data, null, 2), 'utf-8');
  } catch (err) {
    console.error('[GameLibrary] Failed to save data:', err);
  }
}

// ── SSE Broadcast ──

function broadcastUpdate(data: GameLibraryData): void {
  const users = Object.values(data.users).map(u => ({
    steamId: u.steamId,
    personaName: u.personaName,
    avatarUrl: u.avatarUrl,
    gameCount: u.games.length,
    lastUpdated: u.lastUpdated,
  }));
  sseBroadcast({ type: 'game_library_update', plugin: 'game-library', users });
}

// ── Steam API Helpers ──

async function fetchSteamProfile(steamId: string): Promise<{ personaName: string; avatarUrl: string; profileUrl: string }> {
  const url = `https://api.steampowered.com/ISteamUser/GetPlayerSummaries/v2/?key=${STEAM_API_KEY}&steamids=${steamId}`;
  const resp = await fetch(url);
  if (!resp.ok) {
    throw new Error(`Steam API error: ${resp.status} ${resp.statusText}`);
  }
  const json = await resp.json() as any;
  const player = json?.response?.players?.[0];
  if (!player) {
    throw new Error(`Steam user not found: ${steamId}`);
  }
  return {
    personaName: player.personaname || steamId,
    avatarUrl: player.avatarfull || '',
    profileUrl: player.profileurl || '',
  };
}

async function fetchSteamGames(steamId: string): Promise<SteamGame[]> {
  const url = `https://api.steampowered.com/IPlayerService/GetOwnedGames/v1/?key=${STEAM_API_KEY}&steamid=${steamId}&include_appinfo=true&include_played_free_games=true&format=json`;
  const resp = await fetch(url);
  if (!resp.ok) {
    throw new Error(`Steam API error: ${resp.status} ${resp.statusText}`);
  }
  const json = await resp.json() as any;
  const games: SteamGame[] = (json?.response?.games || []).map((g: any) => ({
    appid: g.appid,
    name: g.name || '',
    playtime_forever: g.playtime_forever || 0,
    img_icon_url: g.img_icon_url || '',
  }));
  return games;
}

// ── Plugin ──

const gameLibraryPlugin: Plugin = {
  name: 'game-library',
  version: '1.0.0',
  description: 'Steam Spielebibliothek',

  async init(ctx) {
    loadData(ctx); // ensure file exists
    console.log('[GameLibrary] Initialized');
  },

  registerRoutes(app: express.Application, ctx: PluginContext) {
    // ── Steam OpenID Login ──
    app.get('/api/game-library/steam/login', (_req, res) => {
      const proto = _req.headers['x-forwarded-proto'] || _req.protocol || 'http';
      const host = _req.headers['x-forwarded-host'] || _req.headers.host || 'localhost';
      const realm = `${proto}://${host}`;
      const returnTo = `${realm}/api/game-library/steam/callback`;

      const params = new URLSearchParams({
        'openid.ns': 'http://specs.openid.net/auth/2.0',
        'openid.mode': 'checkid_setup',
        'openid.return_to': returnTo,
        'openid.realm': realm,
        'openid.identity': 'http://specs.openid.net/auth/2.0/identifier_select',
        'openid.claimed_id': 'http://specs.openid.net/auth/2.0/identifier_select',
      });

      res.redirect(`https://steamcommunity.com/openid/login?${params.toString()}`);
    });

    // ── Steam OpenID Callback ──
    app.get('/api/game-library/steam/callback', async (req, res) => {
      try {
        const claimedId = String(req.query['openid.claimed_id'] || '');
        const steamIdMatch = claimedId.match(/\/id\/(\d+)$/);
        if (!steamIdMatch) {
          res.status(400).send(errorPage('Steam-Authentifizierung fehlgeschlagen', 'Keine gueltige Steam-ID erhalten.'));
          return;
        }
        const steamId = steamIdMatch[1];

        // Verify authentication with Steam
        const verifyParams = new URLSearchParams();
        for (const [key, value] of Object.entries(req.query)) {
          verifyParams.set(key, String(value));
        }
        verifyParams.set('openid.mode', 'check_authentication');

        const verifyResp = await fetch(`https://steamcommunity.com/openid/login?${verifyParams.toString()}`);
        const verifyText = await verifyResp.text();

        if (!verifyText.includes('is_valid:true')) {
          res.status(403).send(errorPage('Verifizierung fehlgeschlagen', 'Steam konnte die Anmeldung nicht verifizieren.'));
          return;
        }

        // Fetch profile and games in parallel
        const [profile, games] = await Promise.all([
          fetchSteamProfile(steamId),
          fetchSteamGames(steamId),
        ]);

        // Store user data
        const data = loadData(ctx);
        data.users[steamId] = {
          steamId,
          personaName: profile.personaName,
          avatarUrl: profile.avatarUrl,
          profileUrl: profile.profileUrl,
          games,
          lastUpdated: new Date().toISOString(),
        };
        saveData(ctx, data);
        broadcastUpdate(data);

        // Fire-and-forget IGDB enrichment
        enrichGames(games.map(g => ({ appid: g.appid, name: g.name }))).then(igdbMap => {
          const data2 = loadData(ctx);
          const user2 = data2.users[steamId];
          if (user2) {
            let count = 0;
            for (const game of user2.games) {
              const info = igdbMap.get(game.appid);
              if (info) { game.igdb = info; count++; }
            }
            saveData(ctx, data2);
            console.log(`[GameLibrary] IGDB auto-enrichment: ${count}/${games.length} games`);
          }
        }).catch(err => console.error('[GameLibrary] IGDB auto-enrichment error:', err));

        const personaName = profile.personaName;
        console.log(`[GameLibrary] Steam-Benutzer verknuepft: ${personaName} (${steamId}) - ${games.length} Spiele`);

        res.send(`<!DOCTYPE html><html><head><title>Steam verbunden</title><style>body{background:#1a1a2e;color:#fff;font-family:sans-serif;display:flex;align-items:center;justify-content:center;height:100vh;margin:0}div{text-align:center}h2{color:#2ecc71}</style></head><body><div><h2>Steam verbunden!</h2><p>${personaName} wurde erfolgreich verknuepft.</p><p>${games.length} Spiele geladen.</p><p>Du kannst dieses Fenster schliessen.</p><script>setTimeout(()=>window.close(),3000)</script></div></body></html>`);
      } catch (err) {
        console.error('[GameLibrary] Callback error:', err);
        res.status(500).send(errorPage('Fehler', 'Ein unerwarteter Fehler ist aufgetreten.'));
      }
    });

    // ── GET /api/game-library/users ──
    app.get('/api/game-library/users', (_req, res) => {
      const data = loadData(ctx);
      const users = Object.values(data.users).map(u => ({
        steamId: u.steamId,
        personaName: u.personaName,
        avatarUrl: u.avatarUrl,
        gameCount: u.games.length,
        lastUpdated: u.lastUpdated,
      }));
      res.json({ users });
    });

    // ── GET /api/game-library/user/:steamId ──
    app.get('/api/game-library/user/:steamId', (req, res) => {
      const data = loadData(ctx);
      const user = data.users[req.params.steamId];
      if (!user) {
        res.status(404).json({ error: 'Benutzer nicht gefunden.' });
        return;
      }
      // Sort games by playtime descending
      const sortedGames = [...user.games].sort((a, b) => b.playtime_forever - a.playtime_forever);
      res.json({
        steamId: user.steamId,
        personaName: user.personaName,
        avatarUrl: user.avatarUrl,
        profileUrl: user.profileUrl,
        gameCount: sortedGames.length,
        lastUpdated: user.lastUpdated,
        games: sortedGames,
      });
    });

    // ── GET /api/game-library/common-games?users=id1,id2,... ──
    app.get('/api/game-library/common-games', (req, res) => {
      const userIds = String(req.query.users || '').split(',').filter(Boolean);
      if (userIds.length < 2) {
        res.status(400).json({ error: 'Mindestens zwei Steam-IDs erforderlich (users=id1,id2).' });
        return;
      }

      const data = loadData(ctx);

      // Validate all users exist
      for (const id of userIds) {
        if (!data.users[id]) {
          res.status(404).json({ error: `Benutzer ${id} nicht gefunden.` });
          return;
        }
      }

      // Build game sets per user: Map<appid, SteamGame>
      const userGameMaps = userIds.map(id => {
        const map = new Map<number, SteamGame>();
        for (const game of data.users[id].games) {
          map.set(game.appid, game);
        }
        return { userId: id, gameMap: map };
      });

      // Find intersection: games present in ALL users
      const firstUserGames = userGameMaps[0].gameMap;
      const commonAppIds: number[] = [];

      for (const appid of firstUserGames.keys()) {
        const allOwn = userGameMaps.every(u => u.gameMap.has(appid));
        if (allOwn) {
          commonAppIds.push(appid);
        }
      }

      // Build result with owner info
      const games = commonAppIds.map(appid => {
        const refGame = firstUserGames.get(appid)!;
        const owners = userIds.map(id => {
          const user = data.users[id];
          const userGame = user.games.find(g => g.appid === appid);
          return {
            steamId: user.steamId,
            personaName: user.personaName,
            playtime_forever: userGame?.playtime_forever || 0,
          };
        });
        return {
          appid: refGame.appid,
          name: refGame.name,
          img_icon_url: refGame.img_icon_url,
          ...(refGame.igdb ? { igdb: refGame.igdb } : {}),
          owners,
        };
      });

      // Sort by name
      games.sort((a, b) => a.name.localeCompare(b.name));

      res.json({ games, count: games.length });
    });

    // ── GET /api/game-library/search?q=term ──
    app.get('/api/game-library/search', (req, res) => {
      const query = String(req.query.q || '').trim().toLowerCase();
      if (!query) {
        res.status(400).json({ error: 'Suchbegriff erforderlich (q=...).' });
        return;
      }

      const data = loadData(ctx);
      const allUsers = Object.values(data.users);

      // Collect all unique games matching the query
      const gameMap = new Map<number, { appid: number; name: string; img_icon_url: string; owners: { steamId: string; personaName: string }[] }>();

      for (const user of allUsers) {
        for (const game of user.games) {
          if (game.name.toLowerCase().includes(query)) {
            if (!gameMap.has(game.appid)) {
              gameMap.set(game.appid, {
                appid: game.appid,
                name: game.name,
                img_icon_url: game.img_icon_url,
                owners: [],
              });
            }
            gameMap.get(game.appid)!.owners.push({
              steamId: user.steamId,
              personaName: user.personaName,
            });
          }
        }
      }

      const games = [...gameMap.values()].sort((a, b) => a.name.localeCompare(b.name));
      res.json({ games, count: games.length });
    });

    // ── GET /api/game-library/igdb/enrich/:steamId ──
    app.get('/api/game-library/igdb/enrich/:steamId', async (req, res) => {
      try {
        const { steamId } = req.params;
        const force = req.query.force === 'true';
        const data = loadData(ctx);
        const user = data.users[steamId];
        if (!user) {
          res.status(404).json({ error: 'Benutzer nicht gefunden.' });
          return;
        }

        const gamesToEnrich = force
          ? user.games.map(g => ({ appid: g.appid, name: g.name }))
          : user.games.filter(g => !g.igdb).map(g => ({ appid: g.appid, name: g.name }));

        const igdbMap = await enrichGames(gamesToEnrich);

        // Reload data to avoid stale writes
        const freshData = loadData(ctx);
        const freshUser = freshData.users[steamId];
        if (!freshUser) {
          res.status(404).json({ error: 'Benutzer nicht gefunden.' });
          return;
        }

        let enriched = 0;
        for (const game of freshUser.games) {
          const info = igdbMap.get(game.appid);
          if (info) {
            game.igdb = info;
            enriched++;
          }
        }

        saveData(ctx, freshData);
        console.log(`[GameLibrary] IGDB enrichment for ${freshUser.personaName}: ${enriched}/${freshUser.games.length} games`);

        res.json({ enriched, total: freshUser.games.length });
      } catch (err) {
        console.error('[GameLibrary] IGDB enrich error:', err);
        res.status(500).json({ error: 'Fehler bei der IGDB-Anreicherung.' });
      }
    });

    // ── GET /api/game-library/igdb/game/:appid ──
    app.get('/api/game-library/igdb/game/:appid', async (req, res) => {
      try {
        const appid = parseInt(req.params.appid, 10);
        if (isNaN(appid)) {
          res.status(400).json({ error: 'Ungueltige App-ID.' });
          return;
        }

        // Find game name from any user's library
        const data = loadData(ctx);
        let gameName = '';
        for (const user of Object.values(data.users)) {
          const game = user.games.find(g => g.appid === appid);
          if (game) {
            gameName = game.name;
            break;
          }
        }

        if (!gameName) {
          res.status(404).json({ error: 'Spiel nicht in der Bibliothek gefunden.' });
          return;
        }

        const info = await lookupGame(appid, gameName);
        if (!info) {
          res.status(404).json({ error: 'Spiel nicht in IGDB gefunden.' });
          return;
        }

        res.json(info);
      } catch (err) {
        console.error('[GameLibrary] IGDB game lookup error:', err);
        res.status(500).json({ error: 'Fehler bei der IGDB-Abfrage.' });
      }
    });

    // ── POST /api/game-library/refresh/:steamId ──
    app.post('/api/game-library/refresh/:steamId', async (req, res) => {
      try {
        const { steamId } = req.params;
        const data = loadData(ctx);
        const user = data.users[steamId];
        if (!user) {
          res.status(404).json({ error: 'Benutzer nicht gefunden.' });
          return;
        }

        // Re-fetch profile and games in parallel
        const [profile, games] = await Promise.all([
          fetchSteamProfile(steamId),
          fetchSteamGames(steamId),
        ]);

        data.users[steamId] = {
          steamId,
          personaName: profile.personaName,
          avatarUrl: profile.avatarUrl,
          profileUrl: profile.profileUrl,
          games,
          lastUpdated: new Date().toISOString(),
        };
        saveData(ctx, data);
        broadcastUpdate(data);

        // Fire-and-forget IGDB enrichment
        enrichGames(games.map(g => ({ appid: g.appid, name: g.name }))).then(igdbMap => {
          const data2 = loadData(ctx);
          const user2 = data2.users[steamId];
          if (user2) {
            let count = 0;
            for (const game of user2.games) {
              const info = igdbMap.get(game.appid);
              if (info) { game.igdb = info; count++; }
            }
            saveData(ctx, data2);
            console.log(`[GameLibrary] IGDB auto-enrichment: ${count}/${games.length} games`);
          }
        }).catch(err => console.error('[GameLibrary] IGDB auto-enrichment error:', err));

        console.log(`[GameLibrary] Aktualisiert: ${profile.personaName} (${steamId}) - ${games.length} Spiele`);

        res.json({
          steamId,
          personaName: profile.personaName,
          avatarUrl: profile.avatarUrl,
          profileUrl: profile.profileUrl,
          gameCount: games.length,
          lastUpdated: data.users[steamId].lastUpdated,
        });
      } catch (err) {
        console.error('[GameLibrary] Refresh error:', err);
        res.status(500).json({ error: 'Fehler beim Aktualisieren der Spielebibliothek.' });
      }
    });

    // ── DELETE /api/game-library/user/:steamId ──
    app.delete('/api/game-library/user/:steamId', (req, res) => {
      const { steamId } = req.params;
      const data = loadData(ctx);
      const user = data.users[steamId];
      if (!user) {
        res.status(404).json({ error: 'Benutzer nicht gefunden.' });
        return;
      }

      const personaName = user.personaName;
      delete data.users[steamId];
      saveData(ctx, data);
      broadcastUpdate(data);

      console.log(`[GameLibrary] Benutzer entfernt: ${personaName} (${steamId})`);
      res.json({ success: true, message: `${personaName} wurde entfernt.` });
    });
  },

  getSnapshot(ctx) {
    const data = loadData(ctx);
    return {
      'game-library': {
        users: Object.values(data.users).map(u => ({
          steamId: u.steamId,
          personaName: u.personaName,
          avatarUrl: u.avatarUrl,
          gameCount: u.games.length,
          lastUpdated: u.lastUpdated,
        })),
      },
    };
  },
};

// ── Helper: Error HTML Page ──

function errorPage(title: string, message: string): string {
  return `<!DOCTYPE html><html><head><title>${title}</title><style>body{background:#1a1a2e;color:#fff;font-family:sans-serif;display:flex;align-items:center;justify-content:center;height:100vh;margin:0}div{text-align:center}h2{color:#e74c3c}</style></head><body><div><h2>${title}</h2><p>${message}</p><p>Du kannst dieses Fenster schliessen.</p><script>setTimeout(()=>window.close(),5000)</script></div></body></html>`;
}

export default gameLibraryPlugin;