'use strict';

const express    = require('express');
const http       = require('http');
const https      = require('https');
const { Server } = require('socket.io');
const path       = require('path');
const fs         = require('fs');
const bcrypt     = require('bcryptjs');
const jwt        = require('jsonwebtoken');

const app        = express();
const httpServer = http.createServer(app);

let httpsServer = null;
const SSL_KEY  = path.join(__dirname, 'ssl', 'key.pem');
const SSL_CERT = path.join(__dirname, 'ssl', 'cert.pem');
if (fs.existsSync(SSL_KEY) && fs.existsSync(SSL_CERT)) {
  httpsServer = https.createServer(
    { key: fs.readFileSync(SSL_KEY), cert: fs.readFileSync(SSL_CERT) }, app
  );
}

const io = new Server(httpServer);
if (httpsServer) io.attach(httpsServer);

const JWT_SECRET        = process.env.JWT_SECRET        || 'shelem-secret-change-me';
const ADMIN_USERNAME    = process.env.ADMIN_USERNAME    || '';
const SHARED_USERS_FILE = process.env.SHARED_USERS_FILE || '';
const HTTP_PORT         = parseInt(process.env.PORT       || '4000');
const HTTPS_PORT        = parseInt(process.env.HTTPS_PORT || '4443');

// ─── JSON file database ────────────────────────────────────────
const DATA_DIR = path.join(__dirname, 'data');
if (!fs.existsSync(DATA_DIR)) fs.mkdirSync(DATA_DIR, { recursive: true });

const USERS_FILE  = path.join(DATA_DIR, 'users.json');
const STATS_FILE  = path.join(DATA_DIR, 'stats.json');
const CONFIG_FILE = path.join(DATA_DIR, 'config.json');

function readJSON(file, def) {
  try { return JSON.parse(fs.readFileSync(file, 'utf8')); } catch { return def; }
}
function writeJSON(file, data) {
  const tmp = file + '.tmp';
  fs.writeFileSync(tmp, JSON.stringify(data, null, 2));
  fs.renameSync(tmp, file);
}

let users  = readJSON(USERS_FILE,  []);
let stats  = readJSON(STATS_FILE,  []);
let config = readJSON(CONFIG_FILE, { signupsOpen: true });

function saveUsers()  { writeJSON(USERS_FILE,  users);  }
function saveStats()  { writeJSON(STATS_FILE,  stats);  }
function saveConfig() { writeJSON(CONFIG_FILE, config); }

function isAdmin(user) {
  return ADMIN_USERNAME && user && user.username === ADMIN_USERNAME;
}

let _nextId = users.length > 0 ? Math.max(...users.map(u => u.id)) + 1 : 1;
function nextId() { return _nextId++; }

function findUser(username) {
  const local = users.find(u => u.username.toLowerCase() === username.toLowerCase());
  if (local) return local;
  if (SHARED_USERS_FILE) {
    try {
      const shared = readJSON(SHARED_USERS_FILE, []);
      const s = shared.find(u => u.username.toLowerCase() === username.toLowerCase());
      if (s) return { ...s, _fromShared: true };
    } catch { /* ignore */ }
  }
  return null;
}

function getStats(userId) {
  let s = stats.find(s => s.userId === userId);
  if (!s) {
    s = { userId, games_played: 0, games_won: 0, shelemCount: 0, total_score: 0 };
    stats.push(s);
    saveStats();
  }
  return s;
}

function addStats(userId, delta) {
  const s = getStats(userId);
  s.games_played = (s.games_played || 0) + (delta.games_played || 0);
  s.games_won    = (s.games_won    || 0) + (delta.games_won    || 0);
  s.shelemCount  = (s.shelemCount  || 0) + (delta.shelemCount  || 0);
  s.total_score  = (s.total_score  || 0) + (delta.total_score  || 0);
  saveStats();
}

function requireAuth(req, res, next) {
  const h = req.headers.authorization;
  if (!h?.startsWith('Bearer ')) return res.status(401).json({ error: 'Not authenticated' });
  try { req.user = jwt.verify(h.slice(7), JWT_SECRET); next(); }
  catch { res.status(401).json({ error: 'Invalid or expired token' }); }
}

// ─── Middleware ────────────────────────────────────────────────
app.use(express.json());
app.use(express.static(path.join(__dirname, 'public'), {
  setHeaders: (res, filePath) => {
    if (/\.svg$/.test(filePath)) {
      res.setHeader('Cache-Control', 'public, max-age=2592000, immutable');
    } else if (/\.(js|css|html)$/.test(filePath)) {
      res.setHeader('Cache-Control', 'no-cache');
    }
  }
}));

// ─── Auth API ─────────────────────────────────────────────────
app.get('/api/config', (_req, res) => {
  res.json({ signupsOpen: config.signupsOpen });
});

app.post('/api/register', (req, res) => {
  if (!config.signupsOpen)
    return res.status(403).json({ error: 'New registrations are currently closed.' });
  const { username, password } = req.body || {};
  if (!username || !password)
    return res.status(400).json({ error: 'Username and password are required' });
  if (username.trim().length < 2 || username.trim().length > 16)
    return res.status(400).json({ error: 'Username must be 2–16 characters' });
  if (password.length < 4)
    return res.status(400).json({ error: 'Password must be at least 4 characters' });
  if (findUser(username))
    return res.status(409).json({ error: 'Username already taken' });
  const id = nextId();
  users.push({ id, username: username.trim(), password: bcrypt.hashSync(password, 10) });
  saveUsers();
  getStats(id);
  const token = jwt.sign({ id, username: username.trim() }, JWT_SECRET, { expiresIn: '30d' });
  res.json({ token, username: username.trim() });
});

app.post('/api/login', (req, res) => {
  const { username, password } = req.body || {};
  if (!username || !password)
    return res.status(400).json({ error: 'Username and password required' });
  const user = findUser(username);
  if (!user || !bcrypt.compareSync(password, user.password))
    return res.status(401).json({ error: 'Invalid username or password' });
  const effectiveId       = user._fromShared ? `hokm_${user.id}` : user.id;
  const effectiveUsername = user.username;
  const token = jwt.sign({ id: effectiveId, username: effectiveUsername }, JWT_SECRET, { expiresIn: '30d' });
  res.json({ token, username: effectiveUsername });
});

app.post('/api/change-password', requireAuth, (req, res) => {
  const { currentPassword, newPassword } = req.body || {};
  if (!currentPassword || !newPassword)
    return res.status(400).json({ error: 'Both passwords required' });
  if (newPassword.length < 4)
    return res.status(400).json({ error: 'New password must be at least 4 characters' });
  const user = users.find(u => u.id === req.user.id);
  if (!user) return res.status(404).json({ error: 'User not found (shared accounts cannot change password here)' });
  if (!bcrypt.compareSync(currentPassword, user.password))
    return res.status(401).json({ error: 'Current password is incorrect' });
  user.password = bcrypt.hashSync(newPassword, 10);
  saveUsers();
  res.json({ ok: true });
});

app.get('/api/profile/:username', (req, res) => {
  const user = findUser(req.params.username);
  if (!user) return res.status(404).json({ error: 'User not found' });
  const effectiveId = user._fromShared ? `hokm_${user.id}` : user.id;
  const s = getStats(effectiveId);
  res.json({
    username:     user.username,
    games_played: s.games_played || 0,
    games_won:    s.games_won    || 0,
    shelemCount:  s.shelemCount  || 0,
    total_score:  s.total_score  || 0,
    isAdmin:      isAdmin(user),
    signupsOpen:  config.signupsOpen,
  });
});

app.get('/api/leaderboard', (_req, res) => {
  const allUsers = [...users];
  if (SHARED_USERS_FILE) {
    try {
      const shared = readJSON(SHARED_USERS_FILE, []);
      for (const su of shared) {
        if (!allUsers.find(u => u.username.toLowerCase() === su.username.toLowerCase()))
          allUsers.push({ ...su, _fromShared: true });
      }
    } catch { /* ignore */ }
  }
  const rows = allUsers.map(u => {
    const eid   = u._fromShared ? `hokm_${u.id}` : u.id;
    const s     = getStats(eid);
    const played = s.games_played || 0;
    return {
      username:       u.username,
      games_played:   played,
      games_won:      s.games_won    || 0,
      shelemCount:    s.shelemCount  || 0,
      total_score:    s.total_score  || 0,
      score_per_game: played > 0 ? +((s.total_score || 0) / played).toFixed(1) : null,
    };
  })
  .filter(r => r.games_played > 0)
  .sort((a, b) => {
    if (a.score_per_game === null) return 1;
    if (b.score_per_game === null) return -1;
    return b.score_per_game - a.score_per_game || b.games_played - a.games_played;
  })
  .slice(0, 30);
  res.json(rows);
});

app.get('/api/rooms', (_req, res) => {
  const list = [];
  for (const [, room] of rooms) {
    if (!room.isPublic || room.state !== 'WAITING') continue;
    const playerCount = room.seats.filter(Boolean).length + room.bots.filter(Boolean).length;
    list.push({
      id:          room.id,
      playerCount,
      jokerMode:   room.jokerMode,
      winScore:    room.winScore,
      hostName:    room.names[0] || '?',
    });
  }
  res.json(list);
});

app.post('/api/admin/toggle-signups', requireAuth, (req, res) => {
  if (!isAdmin(req.user)) return res.status(403).json({ error: 'Forbidden' });
  config.signupsOpen = !config.signupsOpen;
  saveConfig();
  res.json({ signupsOpen: config.signupsOpen });
});

// ═══════════════════════════════════════════════════════════════
//  SHELEM GAME ENGINE
// ═══════════════════════════════════════════════════════════════

const SUITS = ['C', 'D', 'H', 'S'];
const RANKS = ['2', '3', '4', '5', '6', '7', '8', '9', '10', 'J', 'Q', 'K', 'A'];
// rank index for non-joker cards: 2→0, A→12
const RANK_IDX = Object.fromEntries(RANKS.map((r, i) => [r, i]));

function makeDeck(jokerMode) {
  const d = [];
  for (const s of SUITS) for (const r of RANKS) d.push(`${s}-${r}`);
  if (jokerMode) { d.push('JOKER-COLOR'); d.push('JOKER-BLACK'); }
  return d;
}

function shuffle(arr) {
  for (let i = arr.length - 1; i > 0; i--) {
    const j = Math.floor(Math.random() * (i + 1));
    [arr[i], arr[j]] = [arr[j], arr[i]];
  }
  return arr;
}

function suitOf(card) {
  if (card === 'JOKER-COLOR' || card === 'JOKER-BLACK') return 'JOKER';
  return card.split('-')[0];
}
function rankOf(card) { return card.split('-')[1]; }

function cardPoints(card) {
  if (card === 'JOKER-COLOR') return 20;
  if (card === 'JOKER-BLACK') return 15;
  const r = rankOf(card);
  if (r === 'A')  return 10;
  if (r === '10') return 10;
  if (r === '5')  return 5;
  return 0;
}

function isJoker(card)  { return card === 'JOKER-COLOR' || card === 'JOKER-BLACK'; }

function isTrump(card, trump) {
  if (!trump) return false;
  return isJoker(card) || suitOf(card) === trump;
}

// Higher = stronger trump. JOKER-COLOR=100, JOKER-BLACK=99, A=12..2=0
function trumpRank(card) {
  if (card === 'JOKER-COLOR') return 100;
  if (card === 'JOKER-BLACK') return 99;
  return RANK_IDX[rankOf(card)];
}

// Suit display order: C D H S JOKER
const SUIT_ORD = { C: 0, D: 1, H: 2, S: 3, JOKER: 4 };
function sortCards(hand) {
  return [...hand].sort((a, b) => {
    const sa = SUIT_ORD[suitOf(a)], sb = SUIT_ORD[suitOf(b)];
    if (sa !== sb) return sa - sb;
    return RANK_IDX[rankOf(a)] - RANK_IDX[rankOf(b)];
  });
}

function teamOf(seat) { return seat % 2; } // 0,2 → team 0 | 1,3 → team 1

function widowSize(room)   { return room.jokerMode ? 6 : 4; }
function discardCount(room){ return widowSize(room); }

function trickWinner(trick, trump) {
  const trumpPlayed = trick.filter(t => isTrump(t.card, trump));
  if (trumpPlayed.length > 0) {
    return trumpPlayed.reduce((best, t) =>
      trumpRank(t.card) > trumpRank(best.card) ? t : best).player;
  }
  const ls = suitOf(trick[0].card);
  const led = trick.filter(t => suitOf(t.card) === ls);
  return led.reduce((best, t) =>
    RANK_IDX[rankOf(t.card)] > RANK_IDX[rankOf(best.card)] ? t : best).player;
}

function legalCards(room, player) {
  const hand  = room.hands[player];
  const trick = room.trick;
  const trump = room.trump;

  if (trick.length === 0) {
    // First card of the hand sets trump — jokers not allowed as the opening lead
    if (trump === null) return hand.filter(c => !isJoker(c));
    return hand;
  }

  const ledCard  = trick[0].card;
  const ledTrump = isTrump(ledCard, trump);

  if (ledTrump) {
    // Trump led — must follow trump
    const trumpCards = hand.filter(c => isTrump(c, trump));
    return trumpCards.length > 0 ? trumpCards : hand;
  }

  // Non-trump led — must follow suit (jokers are NOT the led suit)
  const ls = suitOf(ledCard);
  const suitCards = hand.filter(c => suitOf(c) === ls);
  return suitCards.length > 0 ? suitCards : hand;
}

function makeToken() {
  return Math.random().toString(36).slice(2) + Math.random().toString(36).slice(2);
}

function newRoom(id) {
  return {
    id,
    isPublic: false,
    state: 'WAITING',
    names:   ['', '', '', ''],
    seats:   [null, null, null, null],
    tokens:  [null, null, null, null],
    userIds: [null, null, null, null],
    bots:    [false, false, false, false],
    hands:   [[], [], [], []],
    widow:   [],
    handNumber: 0,
    dealer: 0,
    // Bidding
    bids:             [null, null, null, null],
    currentBidder:    -1,
    highBid:          0,
    highBidder:       -1,
    consecutivePasses: 0,
    // Widow / trump
    declarer:   -1,
    discarded:  [],
    trump:      null,
    // Trick-play
    trick:          [],
    trickLead:      -1,
    currentTurn:    -1,
    tricksPlayed:   0,
    trickWins:      [0, 0, 0, 0],
    teamCardPoints: [0, 0],
    lastTrick:       null,
    lastTrickWinner: -1,
    handDeltas:   null,
    isShelemHand: false,
    gameShelemsCount: 0,
    // Accumulated game scores (per team)
    scores: [0, 0],
    gameWinner: null,
    // Options
    jokerMode: true,
    winScore:  505,
    spectators: new Set(),
    trickTimer: null,
  };
}

function publicInfo(room, seat) {
  return {
    id:    room.id,
    state: room.state,
    names: room.names,
    bots:  room.bots,
    hands: room.hands.map((h, i) => i === seat ? h : h.length),
    // Widow: declarer sees full cards during WIDOW phase, others see count
    widow: (seat === room.declarer && room.state === 'WIDOW')
      ? room.widow
      : (room.state === 'WIDOW' ? room.widow.length : []),
    widowSize:     widowSize(room),
    handNumber:    room.handNumber,
    dealer:        room.dealer,
    bids:          room.bids,
    currentBidder: room.currentBidder,
    highBid:       room.highBid,
    highBidder:    room.highBidder,
    declarer:      room.declarer,
    trump:         room.trump,
    trick:         room.trick,
    trickLead:     room.trickLead,
    currentTurn:   room.currentTurn,
    tricksPlayed:  room.tricksPlayed,
    trickWins:     room.trickWins,
    teamCardPoints: room.teamCardPoints,
    scores:        room.scores,
    handDeltas:    room.handDeltas,
    isShelemHand:  room.isShelemHand,
    lastTrick:       room.lastTrick,
    lastTrickWinner: room.lastTrickWinner,
    gameWinner:    room.gameWinner,
    jokerMode:     room.jokerMode,
    winScore:      room.winScore,
    isPublic:      room.isPublic,
    spectatorCount: room.spectators.size,
  };
}

function broadcastState(room, event = 'roomInfo') {
  for (let i = 0; i < 4; i++) {
    const sid = room.seats[i];
    if (sid) io.to(sid).emit(event, publicInfo(room, i));
  }
  for (const sid of room.spectators) {
    io.to(sid).emit(event, publicInfo(room, -1));
  }
}

// ─── Deal ─────────────────────────────────────────────────────
function dealHand(room) {
  const deck   = shuffle(makeDeck(room.jokerMode));
  const wSize  = widowSize(room);
  const hSize  = (deck.length - wSize) / 4; // always 12

  for (let i = 0; i < 4; i++) {
    room.hands[i] = sortCards(deck.slice(i * hSize, (i + 1) * hSize));
  }
  room.widow = deck.slice(4 * hSize);

  room.trick = []; room.lastTrick = null; room.lastTrickWinner = -1;
  room.trump = null; room.tricksPlayed = 0;
  room.trickWins = [0, 0, 0, 0]; room.teamCardPoints = [0, 0];
  room.handDeltas = null; room.isShelemHand = false;
  room.bids = [null, null, null, null];
  room.consecutivePasses = 0; room.highBid = 0; room.highBidder = -1;
  room.declarer = -1; room.discarded = [];
}

// ─── Bidding ──────────────────────────────────────────────────
function startBidding(room) {
  room.state        = 'BIDDING';
  // Bidding starts at right of dealer (counter-clockwise first seat)
  room.currentBidder = (room.dealer + 3) % 4;
  broadcastState(room, 'roomInfo');
  scheduleBotBid(room);
}

function onBid(room, player, amount) {
  if (room.state !== 'BIDDING')        return;
  if (room.currentBidder !== player)   return;
  if (room.bids[player] === 'pass')    return;

  if (typeof amount === 'number') {
    const minBid = room.jokerMode ? 105 : 85;
    if (amount < minBid || amount % 5 !== 0 || amount <= room.highBid) return;
    room.bids[player]      = amount;
    room.highBid           = amount;
    room.highBidder        = player;
    room.consecutivePasses = 0;

    // If every other player has already passed, no one can outbid — end now
    const canStillBid = room.bids.filter((b, i) => i !== player && b !== 'pass').length;
    if (canStillBid === 0) {
      room.declarer = room.highBidder;
      startWidow(room);
      return;
    }
  } else {
    // pass
    room.bids[player] = 'pass';
    room.consecutivePasses++;

    // All non-high-bidder players have now passed → no one can challenge
    if (room.highBid > 0) {
      const othersPassed = room.bids.every((b, i) => i === room.highBidder || b === 'pass');
      if (othersPassed) {
        room.declarer = room.highBidder;
        startWidow(room);
        return;
      }
    }
  }

  // All four passed → redeal with next dealer (counter-clockwise)
  if (room.highBid === 0 && room.consecutivePasses >= 4) {
    room.handNumber++;
    room.dealer = (room.dealer + 1) % 4;
    dealHand(room);
    startBidding(room);
    return;
  }

  // Three consecutive passes after a bid → bidding ends
  if (room.highBid > 0 && room.consecutivePasses >= 3) {
    room.declarer = room.highBidder;
    startWidow(room);
    return;
  }

  // Advance to next eligible bidder (anti-clockwise: right-first, skip passed)
  let next = (player + 3) % 4;
  let safety = 0;
  while (room.bids[next] === 'pass' && safety++ < 4) next = (next + 3) % 4;
  room.currentBidder = next;
  broadcastState(room, 'roomInfo');
  scheduleBotBid(room);
}

// ─── Widow ────────────────────────────────────────────────────
function startWidow(room) {
  room.state = 'WIDOW';
  // Give widow cards to declarer's hand (they see them all)
  room.hands[room.declarer] = sortCards([...room.hands[room.declarer], ...room.widow]);
  broadcastState(room, 'roomInfo');
  if (room.bots[room.declarer]) setTimeout(() => botDiscard(room, room.declarer), 900);
}

function onDiscard(room, player, cards) {
  if (room.state !== 'WIDOW') return;
  if (room.declarer !== player) return;
  const needed = discardCount(room);
  if (!Array.isArray(cards) || cards.length !== needed) return;
  const unique = [...new Set(cards)];
  if (unique.length !== needed) return;
  const hand = room.hands[player];
  if (!unique.every(c => hand.includes(c))) return;

  // Remove from hand
  for (const c of unique) {
    const idx = room.hands[player].indexOf(c);
    room.hands[player].splice(idx, 1);
  }
  room.discarded = unique;

  // Widow discard counts as first trick for declarer team: 5 pts + card points
  const dTeam = teamOf(player);
  room.teamCardPoints[dTeam] += 5;
  for (const c of unique) room.teamCardPoints[dTeam] += cardPoints(c);

  startPlaying(room);
}

// ─── Playing ──────────────────────────────────────────────────
function startPlaying(room) {
  room.state       = 'PLAYING';
  room.trickLead   = room.declarer;
  room.currentTurn = room.declarer;
  room.trick       = [];
  broadcastState(room, 'roomInfo');
  scheduleBotPlay(room);
}

function onCardPlayed(room, player, card) {
  // First card played by the declarer sets trump (jokers excluded by legalCards)
  if (room.trump === null) room.trump = suitOf(card);

  room.hands[player] = room.hands[player].filter(c => c !== card);
  room.trick.push({ card, player });

  if (room.trick.length < 4) {
    room.currentTurn = (player + 3) % 4; // anti-clockwise: next player is to the right
    broadcastState(room, 'cardPlayed');
    scheduleBotPlay(room);
    return;
  }

  // Trick complete
  const winner     = trickWinner(room.trick, room.trump);
  const winnerTeam = teamOf(winner);
  const trickPts   = room.trick.reduce((s, t) => s + cardPoints(t.card), 0);
  room.teamCardPoints[winnerTeam] += trickPts + 5; // 5 per trick won
  room.trickWins[winner]++;
  room.tricksPlayed++;
  room.lastTrick       = room.trick.slice();
  room.lastTrickWinner = winner;

  if (room.tricksPlayed === 12) {
    broadcastState(room, 'trickWon');
    if (room.trickTimer) clearTimeout(room.trickTimer);
    room.trickTimer = setTimeout(() => finishHand(room), 1400);
  } else {
    broadcastState(room, 'trickWon');
    if (room.trickTimer) clearTimeout(room.trickTimer);
    room.trickTimer = setTimeout(() => {
      room.trickLead   = winner;
      room.currentTurn = winner;
      room.trick       = [];
      broadcastState(room, 'roomInfo');
      scheduleBotPlay(room);
    }, 1400);
  }
}

// ─── Hand scoring ─────────────────────────────────────────────
function finishHand(room) {
  const dTeam = teamOf(room.declarer);
  const oTeam = 1 - dTeam;

  const dPts = room.teamCardPoints[dTeam];
  const oPts = room.teamCardPoints[oTeam];

  // Declarer team won all 12 tricks + the widow trick = 13 total tricks
  const dTricks = room.trickWins.reduce((s, w, i) => teamOf(i) === dTeam ? s + w : s, 0) + 1;

  let dDelta = 0, oDelta = 0;

  if (dTricks === 13) {
    // Shelem — win every trick
    dDelta = 250;
    oDelta = 0;
    room.isShelemHand = true;
    room.gameShelemsCount++;
  } else if (dPts >= room.highBid) {
    // Made the bid — score exactly what was bid, not actual points earned
    dDelta = room.highBid;
    oDelta = oPts;
  } else {
    // Failed the bid
    dDelta = dPts >= oPts ? -room.highBid : -2 * room.highBid;
    oDelta = oPts;
  }

  room.handDeltas = [0, 0];
  room.handDeltas[dTeam] = dDelta;
  room.handDeltas[oTeam] = oDelta;
  room.scores[0] += room.handDeltas[0];
  room.scores[1] += room.handDeltas[1];

  if (room.scores.some(s => s >= room.winScore)) {
    finishGame(room);
    return;
  }

  room.state = 'HAND_OVER';
  broadcastState(room, 'handOver');

  if (room.trickTimer) clearTimeout(room.trickTimer);
  room.trickTimer = setTimeout(() => {
    room.handNumber++;
    room.dealer = (room.dealer + 1) % 4; // counter-clockwise rotation
    dealHand(room);
    startBidding(room);
  }, 4500);
}

function finishGame(room) {
  const maxScore = Math.max(...room.scores);
  room.gameWinner = room.scores
    .map((s, i) => ({ s, i }))
    .filter(x => x.s === maxScore)
    .map(x => x.i); // team indices
  room.state = 'GAME_OVER';
  broadcastState(room, 'gameOver');

  if (room.bots.some(Boolean)) return;

  const winnerTeams = new Set(room.gameWinner);
  for (let seat = 0; seat < 4; seat++) {
    const uid = room.userIds[seat];
    if (!uid) continue;
    const team = teamOf(seat);
    addStats(uid, {
      games_played: 1,
      games_won:    winnerTeams.has(team) ? 1 : 0,
      shelemCount:  room.gameShelemsCount,
      total_score:  room.scores[team],
    });
  }
}

// ─── Game init ────────────────────────────────────────────────
function tryStartGame(room) {
  const filled = room.seats.map((s, i) => !!s || room.bots[i]);
  if (!filled.every(Boolean)) return;
  dealHand(room);
  startBidding(room);
}

// ─── Bot: bidding ─────────────────────────────────────────────
function scheduleBotBid(room) {
  if (room.state !== 'BIDDING') return;
  const bot = room.currentBidder;
  if (!room.bots[bot]) return;
  setTimeout(() => {
    if (room.state !== 'BIDDING' || room.currentBidder !== bot) return;
    botBid(room, bot);
  }, 600 + Math.random() * 500);
}

function botBid(room, bot) {
  const hand = room.hands[bot];
  let estimate = 0;

  for (const card of hand) estimate += cardPoints(card);

  // Estimate trick wins from strong cards
  let tricks = 0;
  for (const card of hand) {
    if (card === 'JOKER-COLOR')   tricks += 1;
    else if (card === 'JOKER-BLACK') tricks += 0.95;
    else if (rankOf(card) === 'A')   tricks += 0.85;
    else if (rankOf(card) === 'K')   tricks += 0.4;
  }
  // Long-suit bonus (potential trump)
  const sc = { C: 0, D: 0, H: 0, S: 0 };
  for (const card of hand) { const s = suitOf(card); if (sc[s] !== undefined) sc[s]++; }
  const longest = Math.max(...Object.values(sc));
  if (longest >= 5) tricks += 1.5;
  if (longest >= 6) tricks += 1;

  estimate += Math.round(tricks) * 5;
  let bidAmount = Math.round(estimate / 5) * 5;
  if (Math.random() > 0.6) bidAmount += 5; // slight aggression
  bidAmount = Math.round(bidAmount / 5) * 5;

  const minBid = room.jokerMode ? 105 : 85;
  if (bidAmount > room.highBid && bidAmount >= minBid) {
    onBid(room, bot, bidAmount);
  } else {
    onBid(room, bot, 'pass');
  }
}

// ─── Bot: discard ─────────────────────────────────────────────
function botDiscard(room, bot) {
  const hand = [...room.hands[bot]];

  // Score each card — lower = prefer to discard
  const keepScore = (card) => {
    if (card === 'JOKER-COLOR')  return 200;
    if (card === 'JOKER-BLACK')  return 190;
    const cp = cardPoints(card);
    if (cp >= 10) return 100 + cp; // Aces and Tens: keep
    if (cp === 5) return 60;       // Fives: keep but lower priority
    // Low cards: prefer to discard
    return RANK_IDX[rankOf(card)];
  };

  const sorted    = [...hand].sort((a, b) => keepScore(a) - keepScore(b));
  const toDiscard = sorted.slice(0, discardCount(room));
  onDiscard(room, bot, toDiscard);
}

// ─── Bot: play ────────────────────────────────────────────────
function scheduleBotPlay(room) {
  if (room.state !== 'PLAYING') return;
  const bot = room.currentTurn;
  if (!room.bots[bot]) return;
  const delay = 500 + Math.random() * 600;
  setTimeout(() => {
    if (room.state !== 'PLAYING' || room.currentTurn !== bot) return;
    const card = botChooseCard(room, bot);
    if (card) onCardPlayed(room, bot, card);
  }, delay);
}

function botChooseCard(room, bot) {
  const legal   = legalCards(room, bot);
  if (legal.length === 1) return legal[0];
  const trick   = room.trick;
  const trump   = room.trump;
  const botTeam = teamOf(bot);

  // Leading
  if (trick.length === 0) {
    const trumpCards = legal.filter(c => isTrump(c, trump));
    if (trumpCards.length >= 3) {
      // Lead highest trump to draw out opponents'
      return trumpCards.sort((a, b) => trumpRank(b) - trumpRank(a))[0];
    }
    // Lead high card from longest suit
    const nonJoker = legal.filter(c => !isJoker(c));
    if (nonJoker.length > 0) {
      return nonJoker.sort((a, b) => RANK_IDX[rankOf(b)] - RANK_IDX[rankOf(a)])[0];
    }
    return legal[0];
  }

  // Following
  const curWinner     = trickWinner(trick, trump);
  const curWinnerTeam = teamOf(curWinner);
  const trickPts      = trick.reduce((s, t) => s + cardPoints(t.card), 0);
  const partnerLeading = curWinnerTeam === botTeam;

  if (partnerLeading) {
    // Let partner win — play lowest card
    return legal.sort((a, b) => {
      const av = cardPoints(a) * 20 + trumpRank(a);
      const bv = cardPoints(b) * 20 + trumpRank(b);
      return av - bv;
    })[0];
  }

  // Opponent leading — try to win
  const winning = legal.filter(c => {
    const hyp = [...trick, { card: c, player: bot }];
    return trickWinner(hyp, trump) === bot;
  });

  if (winning.length > 0) {
    // Win with cheapest winning card (preserve high trumps)
    return winning.sort((a, b) => {
      // Prefer non-joker wins to save jokers
      const ai = isJoker(a) ? 2 : 1, bi = isJoker(b) ? 2 : 1;
      if (ai !== bi) return ai - bi;
      return trumpRank(a) - trumpRank(b);
    })[0];
  }

  // Can't win — discard lowest value card
  return legal.sort((a, b) => {
    const av = cardPoints(a) * 20 + RANK_IDX[rankOf(a)];
    const bv = cardPoints(b) * 20 + RANK_IDX[rankOf(b)];
    return av - bv;
  })[0];
}

// ═══════════════════════════════════════════════════════════════
//  SOCKET.IO
// ═══════════════════════════════════════════════════════════════

const rooms      = new Map();
const userSockets = new Map();

io.use((socket, next) => {
  const token = socket.handshake.auth?.token;
  if (token) {
    try { socket.data.user = jwt.verify(token, JWT_SECRET); } catch { /* guest */ }
  }
  next();
});

io.on('connection', (socket) => {
  const user = socket.data.user;
  if (user) {
    userSockets.set(user.id, socket.id);
    // Notify authenticated user if they have an in-progress game (enables cross-device rejoin)
    for (const [, room] of rooms) {
      const seat = room.userIds.indexOf(user.id);
      if (seat >= 0 && room.tokens[seat] !== null && room.state !== 'GAME_OVER') {
        socket.emit('hasActiveGame', { roomId: room.id, seat, token: room.tokens[seat] });
        break;
      }
    }
  }

  // ── Create room ────────────────────────────────────────────
  socket.on('create', ({ name, jokerMode, winScore, isPublic } = {}) => {
    if (!name?.trim()) return socket.emit('error', 'Name is required');
    const id   = Math.random().toString(36).slice(2, 8).toUpperCase();
    const room = newRoom(id);
    room.jokerMode = jokerMode !== false;
    room.isPublic  = isPublic === true;
    const ws = [205, 505, 1005];
    room.winScore  = ws.includes(+winScore) ? +winScore : 505;
    room.names[0]   = name.trim().slice(0, 16);
    room.userIds[0] = user?.id || null;
    room.seats[0]   = socket.id;
    room.tokens[0]  = makeToken();
    rooms.set(id, room);
    socket.join(id);
    socket.emit('created', { roomId: id, seat: 0, token: room.tokens[0] });
    socket.emit('roomInfo', publicInfo(room, 0));
  });

  // ── Join room ──────────────────────────────────────────────
  socket.on('join', ({ name, roomId } = {}) => {
    if (!name?.trim()) return socket.emit('joinError', 'Name is required');
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return socket.emit('joinError', 'Room not found');
    if (room.state !== 'WAITING') return socket.emit('joinError', 'Game already in progress');

    // Prevent the same socket, user, or name from occupying more than one seat
    const trimmedName = name.trim().toLowerCase();
    for (let i = 0; i < 4; i++) {
      if (room.seats[i] === socket.id) return socket.emit('joinError', 'You are already in this room');
      if (user?.id && room.userIds[i] === user.id) return socket.emit('joinError', 'You are already in this room');
      if (room.seats[i] && room.names[i].toLowerCase() === trimmedName)
        return socket.emit('joinError', 'That name is already taken in this room');
    }

    // For public rooms assign a random open seat; private rooms take first open seat
    const openSeats = [];
    for (let i = 0; i < 4; i++) {
      if (!room.seats[i] && !room.bots[i]) openSeats.push(i);
    }
    if (openSeats.length === 0) return socket.emit('joinError', 'Room is full');
    const openSeat = room.isPublic
      ? openSeats[Math.floor(Math.random() * openSeats.length)]
      : openSeats[0];

    room.names[openSeat]   = name.trim().slice(0, 16);
    room.userIds[openSeat] = user?.id || null;
    room.seats[openSeat]   = socket.id;
    room.tokens[openSeat]  = makeToken();
    socket.join(room.id);
    socket.emit('joined', { roomId: room.id, seat: openSeat, token: room.tokens[openSeat] });
    broadcastState(room, 'roomInfo');

    if (room.seats.filter(Boolean).length + room.bots.filter(Boolean).length === 4) tryStartGame(room);
  });

  // ── Spectate ───────────────────────────────────────────────
  socket.on('spectate', ({ roomId } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return socket.emit('spectateError', 'Room not found');
    room.spectators.add(socket.id);
    socket.join(room.id);
    socket.emit('spectating', { roomId: room.id });
    socket.emit('roomInfo', publicInfo(room, -1));
  });

  // ── Rejoin ─────────────────────────────────────────────────
  socket.on('rejoin', ({ roomId, seat, token } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return socket.emit('rejoinError', 'not_found');

    const tokenOk = room.tokens[seat] === token;
    const userOk  = user && room.userIds[seat] != null
                    && room.userIds[seat] === user.id
                    && room.tokens[seat] !== null; // null means player explicitly left

    if (!tokenOk && !userOk) return socket.emit('rejoinError', 'bad_token');

    // Re-issue token when only userId matched (e.g. different device)
    if (!tokenOk) room.tokens[seat] = makeToken();

    room.seats[seat] = socket.id;
    socket.join(room.id);
    socket.emit('rejoined', { roomId: room.id, seat, token: room.tokens[seat] });
    socket.emit('roomInfo', publicInfo(room, seat));
    broadcastState(room, 'roomInfo');
  });

  // ── Fill with bots ─────────────────────────────────────────
  socket.on('fillBots', ({ roomId } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room || room.state !== 'WAITING') return;
    if (!room.seats.includes(socket.id)) return;
    const botNames = ['Ali', 'Mina', 'Reza', 'Sara'];
    for (let i = 0; i < 4; i++) {
      if (!room.seats[i] && !room.bots[i]) {
        room.bots[i]  = true;
        room.names[i] = botNames[i];
      }
    }
    broadcastState(room, 'roomInfo');
    tryStartGame(room);
  });

  // ── Swap seats (creator only) ──────────────────────────────
  socket.on('swapSeats', ({ roomId, seatA, seatB } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room || room.state !== 'WAITING') return;
    const isCreator = room.seats[0] === socket.id ||
                      (user?.id && room.userIds[0] === user.id);
    if (!isCreator) return;
    if (seatA === seatB || ![0,1,2,3].includes(seatA) || ![0,1,2,3].includes(seatB)) return;

    for (const key of ['names', 'seats', 'tokens', 'userIds', 'bots']) {
      [room[key][seatA], room[key][seatB]] = [room[key][seatB], room[key][seatA]];
    }
    // Tell each affected human player their new seat and token
    if (room.seats[seatA]) io.to(room.seats[seatA]).emit('seatChanged', { seat: seatA, token: room.tokens[seatA] });
    if (room.seats[seatB]) io.to(room.seats[seatB]).emit('seatChanged', { seat: seatB, token: room.tokens[seatB] });
    broadcastState(room, 'roomInfo');
  });

  // ── Force start (creator only, fills remaining seats with bots) ──
  socket.on('forceStart', ({ roomId } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room || room.state !== 'WAITING') return;
    const isCreator = room.seats[0] === socket.id ||
                      (user?.id && room.userIds[0] === user.id);
    if (!isCreator) return;
    const botNames = ['Ali', 'Mina', 'Reza', 'Sara'];
    for (let i = 0; i < 4; i++) {
      if (!room.seats[i] && !room.bots[i]) {
        room.bots[i]  = true;
        room.names[i] = botNames[i];
      }
    }
    dealHand(room);
    startBidding(room);
  });

  // ── Bid ────────────────────────────────────────────────────
  socket.on('bid', ({ roomId, seat, token, amount } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return;
    if (room.tokens[seat] !== token) return;
    onBid(room, seat, amount === 'pass' ? 'pass' : +amount);
  });

  // ── Discard widow cards ────────────────────────────────────
  socket.on('discard', ({ roomId, seat, token, cards } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return;
    if (room.tokens[seat] !== token) return;
    onDiscard(room, seat, cards);
  });

  // ── Play card ──────────────────────────────────────────────
  socket.on('play', ({ roomId, seat, token, card } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return;
    if (room.state !== 'PLAYING') return;
    if (room.tokens[seat] !== token) return;
    if (room.currentTurn !== seat) return socket.emit('playError', 'Not your turn');
    if (!legalCards(room, seat).includes(card)) return socket.emit('playError', 'Illegal card');
    onCardPlayed(room, seat, card);
  });

  // ── Leave ──────────────────────────────────────────────────
  socket.on('leave', ({ roomId, seat, token } = {}) => {
    const room = rooms.get((roomId || '').toUpperCase());
    if (!room) return;
    if (room.tokens[seat] === token) {
      room.seats[seat]   = null;
      room.tokens[seat]  = null;
      room.userIds[seat] = null; // prevent hasActiveGame from pulling them back in
    }
    socket.leave(room.id);
  });

  socket.on('disconnect', () => {
    if (user) userSockets.delete(user.id);
  });
});

// ─── Start ────────────────────────────────────────────────────
httpServer.listen(HTTP_PORT, () =>
  console.log(`Shelem HTTP  → http://localhost:${HTTP_PORT}`)
);
if (httpsServer) {
  httpsServer.listen(HTTPS_PORT, () =>
    console.log(`Shelem HTTPS → https://localhost:${HTTPS_PORT}`)
  );
}