const express = require('express');
const http = require('http');
const { Server } = require('socket.io');
const path = require('path');
const wordLists = require('./words');

const app = express();
const server = http.createServer(app);
const io = new Server(server, { cors: { origin: '*' } });
const PORT = process.env.PORT || 7860;

app.use(express.static(path.join(__dirname, 'public')));
// /game now served by index.html (single page app)
app.get('*', (req, res) => res.sendFile(path.join(__dirname, 'public', 'index.html')));

// ─── In-memory game state ───────────────────────────────────────────────────
const rooms = {};

function genCode() {
  let code;
  do { code = Math.random().toString(36).substring(2, 8).toUpperCase(); } while (rooms[code]);
  return code;
}

function getWords(settings, count = 3) {
  let pool = [];
  if (settings.wordMode === 'custom' && settings.customWords.length >= count) {
    pool = [...settings.customWords];
  } else if (settings.wordMode === 'mixed') {
    const cats = settings.categories || Object.keys(wordLists);
    cats.forEach(c => { if (wordLists[c]) pool = pool.concat(wordLists[c]); });
    pool = pool.concat(settings.customWords || []);
  } else {
    const cats = settings.categories || Object.keys(wordLists);
    cats.forEach(c => { if (wordLists[c]) pool = pool.concat(wordLists[c]); });
  }
  pool = [...new Set(pool)];
  const choices = [];
  while (choices.length < count && pool.length > 0) {
    const i = Math.floor(Math.random() * pool.length);
    choices.push(pool.splice(i, 1)[0]);
  }
  return choices;
}

function hintMask(word, revealed) {
  return word.split('').map((c, i) => c === ' ' ? ' ' : revealed.includes(i) ? c : '_').join('');
}

function levenshtein(a, b) {
  const dp = Array.from({ length: a.length + 1 }, (_, i) =>
    Array.from({ length: b.length + 1 }, (_, j) => i === 0 ? j : j === 0 ? i : 0));
  for (let i = 1; i <= a.length; i++)
    for (let j = 1; j <= b.length; j++)
      dp[i][j] = a[i-1] === b[j-1] ? dp[i-1][j-1] : 1 + Math.min(dp[i-1][j], dp[i][j-1], dp[i-1][j-1]);
  return dp[a.length][b.length];
}

function createRoom(settings = {}) {
  const id = genCode();
  rooms[id] = {
    id,
    host: null,
    players: [],
    spectators: [],
    state: 'waiting',
    settings: {
      maxPlayers: 10,
      rounds: 3,
      drawTime: 80,
      wordChoices: 3,
      customWords: [],
      wordMode: 'normal',
      categories: Object.keys(wordLists),
      teamMode: false,
      suddenDeath: false,
      quickDraw: false,
      hintsEnabled: true,
      ...settings
    },
    currentRound: 0,
    drawerOrder: [],
    currentDrawerIndex: 0,
    currentWord: null,
    wordChoices: [],
    drawStrokes: [],
    timer: null,
    chooseTimer: null,
    hintTimer1: null,
    hintTimer2: null,
    timeLeft: 0,
    totalTime: 80,
    hintsRevealed: [],
    roundStartTime: null,
    roundScores: [],
    usedWords: [],
    teams: { red: [], blue: [] },
    scoreHistory: [], // [{round, scores:[{id,score}]}] for graph
  };
  return id;
}

function addPlayer(room, sid, name, avatar) {
  const player = {
    id: sid,
    name: (name || 'Player').substring(0, 20),
    score: 0,
    avatar: avatar || { color: `hsl(${Math.floor(Math.random()*360)},70%,60%)`, icon: '😀' },
    team: null,
    streak: 0,
    powerUps: { revealLetter: 1, timeWarp: 1, bomb: 1 },
    achievements: [],
    isDrawing: false,
    hasGuessed: false,
    guessTime: null,
    isSpectator: false,
    wordsDrawn: 0,
  };
  room.players.push(player);
  return player;
}

function getPlayer(room, sid) {
  return room.players.find(p => p.id === sid) || room.spectators.find(p => p.id === sid);
}

function clearAllTimers(room) {
  if (room.timer) { clearInterval(room.timer); room.timer = null; }
  if (room.chooseTimer) { clearTimeout(room.chooseTimer); room.chooseTimer = null; }
  if (room.hintTimer1) { clearTimeout(room.hintTimer1); room.hintTimer1 = null; }
  if (room.hintTimer2) { clearTimeout(room.hintTimer2); room.hintTimer2 = null; }
}

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 getRoomData(room) {
  return {
    id: room.id,
    host: room.host,
    state: room.state,
    settings: room.settings,
    players: room.players,
    spectators: room.spectators,
    currentRound: room.currentRound,
    totalRounds: room.settings.rounds,
    teams: room.teams,
  };
}

function broadcastPlayers(room) {
  io.to(room.id).emit('playerUpdate', { players: room.players });
}

// ─── Game Flow ───────────────────────────────────────────────────────────────
function startGame(room) {
  if (room.players.length === 0) return;
  room.state = 'playing';
  room.currentRound = 1;
  room.scoreHistory = [];
  room.usedWords = [];
  room.players.forEach(p => {
    p.score = 0; p.streak = 0; p.achievements = [];
    p.powerUps = { revealLetter: 1, timeWarp: 1, bomb: 1 };
  });

  if (room.settings.teamMode) assignTeams(room);

  room.drawerOrder = shuffle(room.players.map(p => p.id));
  room.currentDrawerIndex = 0;
  startRound(room);
}

function assignTeams(room) {
  room.teams = { red: [], blue: [] };
  room.players.forEach((p, i) => {
    p.team = i % 2 === 0 ? 'red' : 'blue';
    room.teams[p.team].push(p.id);
  });
}

function startRound(room) {
  clearAllTimers(room);
  room.players.forEach(p => { p.hasGuessed = false; p.isDrawing = false; p.guessTime = null; });
  room.drawStrokes = [];
  room.hintsRevealed = [];
  room.roundScores = [];
  room.currentWord = null;

  // Find drawer, skip if missing
  let drawerFound = false;
  while (!drawerFound && room.currentDrawerIndex < room.drawerOrder.length) {
    const drawerId = room.drawerOrder[room.currentDrawerIndex];
    const drawer = room.players.find(p => p.id === drawerId);
    if (drawer) { drawer.isDrawing = true; drawerFound = true; }
    else room.currentDrawerIndex++;
  }

  if (!drawerFound) { nextTurn(room); return; }

  const drawer = room.players.find(p => p.isDrawing);
  const choices = getWords(room.settings, room.settings.wordChoices);
  room.wordChoices = choices;
  room.state = 'choosing';

  io.to(room.id).emit('roundStart', {
    round: room.currentRound,
    totalRounds: room.settings.rounds,
    drawer: { id: drawer.id, name: drawer.name, avatar: drawer.avatar },
    players: room.players,
  });

  io.to(drawer.id).emit('chooseWord', { choices });

  room.chooseTimer = setTimeout(() => {
    if (room.state === 'choosing') {
      wordChosen(room, choices[Math.floor(Math.random() * choices.length)]);
    }
  }, 15000);
}

function wordChosen(room, word) {
  clearAllTimers(room);
  room.currentWord = word;
  room.usedWords.push(word);
  room.state = 'drawing';

  const drawTime = room.settings.quickDraw ? 20 : room.settings.drawTime;
  room.timeLeft = drawTime;
  room.totalTime = drawTime;
  room.roundStartTime = Date.now();

  const drawer = room.players.find(p => p.isDrawing);
  const mask = hintMask(word, []);
  const lengths = word.split(' ').map(w => w.length);

  io.to(drawer.id).emit('wordChosen', { word, hint: mask, lengths, isDrawer: true });
  socket_to_room_except(room.id, drawer.id, 'wordChosen', { word: null, hint: mask, lengths, isDrawer: false });

  // Auto hints
  if (room.settings.hintsEnabled) {
    room.hintTimer1 = setTimeout(() => { if (room.state === 'drawing') revealHint(room); }, drawTime * 500);
    room.hintTimer2 = setTimeout(() => { if (room.state === 'drawing') revealHint(room); }, drawTime * 750);
  }

  // Countdown
  room.timer = setInterval(() => {
    room.timeLeft--;
    io.to(room.id).emit('timerUpdate', { timeLeft: room.timeLeft, totalTime: room.totalTime });
    if (room.timeLeft <= 0) endRound(room);
  }, 1000);
}

function socket_to_room_except(roomId, exceptId, event, data) {
  io.to(roomId).except(exceptId).emit(event, data);
}

function revealHint(room) {
  const word = room.currentWord;
  if (!word) return;
  const unrevealed = [];
  word.split('').forEach((c, i) => { if (c !== ' ' && !room.hintsRevealed.includes(i)) unrevealed.push(i); });
  if (unrevealed.length === 0) return;
  const n = Math.max(1, Math.floor(unrevealed.length * 0.3));
  const picks = shuffle([...unrevealed]).slice(0, n);
  room.hintsRevealed.push(...picks);
  const drawer = room.players.find(p => p.isDrawing);
  const hint = hintMask(word, room.hintsRevealed);
  socket_to_room_except(room.id, drawer?.id || '', 'hintUpdate', { hint, revealed: room.hintsRevealed });
}

function checkGuess(room, sid, text) {
  if (!room.currentWord || room.state !== 'drawing') return 'ignore';
  const player = room.players.find(p => p.id === sid);
  if (!player || player.hasGuessed || player.isDrawing) return 'ignore';

  const guess = text.trim().toLowerCase();
  const answer = room.currentWord.toLowerCase();

  if (guess === answer) {
    const elapsed = (Date.now() - room.roundStartTime) / 1000;
    const timeRatio = Math.max(0, 1 - elapsed / room.totalTime);
    const baseScore = 200;
    const timeBonus = Math.round(timeRatio * 300);
    const firstBonus = room.roundScores.length === 0 ? 50 : 0;
    const streakBonus = player.streak * 25;
    const total = baseScore + timeBonus + firstBonus + streakBonus;

    player.hasGuessed = true;
    player.guessTime = elapsed;
    player.score += total;
    player.streak++;
    player.wordsDrawn;

    const drawer = room.players.find(p => p.isDrawing);
    if (drawer) {
      const drawerGain = Math.round(50 + (room.roundScores.length === 0 ? 0 : 10));
      drawer.score += drawerGain;
    }

    room.roundScores.push({ id: sid, score: total, time: elapsed });
    checkAchievements(room, player);

    const nonDrawers = room.players.filter(p => !p.isDrawing && !p.isSpectator);
    if (nonDrawers.every(p => p.hasGuessed)) setTimeout(() => endRound(room), 1500);

    return { correct: true, score: total, streak: player.streak, firstBonus };
  }

  const dist = levenshtein(guess, answer);
  if (dist <= 2 && guess.length > 2) return 'close';

  if (room.settings.suddenDeath) {
    player.score = Math.max(0, player.score - 15);
    broadcastPlayers(room);
  }
  return 'wrong';
}

function checkAchievements(room, player) {
  const unlocked = [];
  const add = (id, name, desc) => {
    if (!player.achievements.includes(id)) {
      player.achievements.push(id);
      unlocked.push({ id, name, desc });
    }
  };
  if (player.guessTime < 8) add('speed_demon', '⚡ Speed Demon', 'Guessed in under 8 seconds!');
  if (player.streak >= 3) add('on_fire', '🔥 On Fire', '3 correct guesses in a row!');
  if (player.streak >= 5) add('unstoppable', '💎 Unstoppable', '5 in a row!');
  if (room.roundScores.length === 1) add('first_blood', '🩸 First Blood', 'First to guess the word!');
  if (room.hintsRevealed.length === 0 && player.guessTime < room.totalTime * 0.5)
    add('no_hints', '🕵️ Sherlock', 'Guessed with zero hints revealed!');
  if (unlocked.length > 0) io.to(player.id).emit('achievementUnlocked', unlocked);
}

function endRound(room) {
  clearAllTimers(room);
  if (room.state === 'intermission' || room.state === 'ended') return;
  room.state = 'intermission';

  const drawer = room.players.find(p => p.isDrawing);

  // Picasso achievement
  const nonDrawers = room.players.filter(p => !p.isDrawing && !p.isSpectator);
  if (drawer && nonDrawers.length > 0 && nonDrawers.every(p => p.hasGuessed)) {
    if (!drawer.achievements.includes('picasso')) {
      drawer.achievements.push('picasso');
      io.to(drawer.id).emit('achievementUnlocked', [{ id: 'picasso', name: '🎨 Picasso', desc: 'Everyone guessed your drawing!' }]);
    }
    drawer.score += 100; // bonus
  }

  // Record score history
  room.scoreHistory.push({
    round: room.currentRound,
    drawerTurn: room.currentDrawerIndex,
    scores: room.players.map(p => ({ id: p.id, name: p.name, score: p.score }))
  });

  io.to(room.id).emit('roundEnd', {
    word: room.currentWord,
    scores: room.players.map(p => ({
      id: p.id, name: p.name, score: p.score, avatar: p.avatar,
      roundGain: room.roundScores.find(r => r.id === p.id)?.score || 0,
      guessTime: p.guessTime,
    })),
    drawStrokes: room.drawStrokes,
    drawer: drawer ? { id: drawer.id, name: drawer.name } : null,
    scoreHistory: room.scoreHistory,
  });

  room.timer = setTimeout(() => {
    if (!rooms[room.id]) return;
    nextTurn(room);
  }, 7000);
}

function nextTurn(room) {
  clearAllTimers(room);
  room.currentDrawerIndex++;

  if (room.currentDrawerIndex >= room.drawerOrder.length) {
    room.currentRound++;
    if (room.currentRound > room.settings.rounds) { endGame(room); return; }
    room.drawerOrder = shuffle(room.players.map(p => p.id));
    room.currentDrawerIndex = 0;
  }

  if (room.players.length < 1) {
    room.state = 'waiting';
    io.to(room.id).emit('gameAborted', { reason: 'Not enough players' });
    return;
  }
  startRound(room);
}

function endGame(room) {
  clearAllTimers(room);
  room.state = 'ended';

  const sorted = [...room.players].sort((a, b) => b.score - a.score);

  // Victory achievement
  if (sorted[0]) {
    const winner = sorted[0];
    if (!winner.achievements.includes('champion')) {
      winner.achievements.push('champion');
      io.to(winner.id).emit('achievementUnlocked', [{ id: 'champion', name: '👑 Champion', desc: 'You won the game!' }]);
    }
  }

  io.to(room.id).emit('gameEnd', {
    players: sorted.map((p, i) => ({
      id: p.id, name: p.name, score: p.score,
      rank: i + 1, achievements: p.achievements, avatar: p.avatar, streak: p.streak
    })),
    scoreHistory: room.scoreHistory,
  });

  setTimeout(() => { if (rooms[room.id]) delete rooms[room.id]; }, 60000);
}

// ─── Socket.IO ───────────────────────────────────────────────────────────────
io.on('connection', (socket) => {

  socket.on('createRoom', ({ name, avatar, settings }) => {
    const id = createRoom(settings || {});
    const room = rooms[id];
    room.host = socket.id;
    const player = addPlayer(room, socket.id, name, avatar);
    socket.join(id);
    socket.roomId = id;
    socket.emit('roomCreated', { roomId: id, player, room: getRoomData(room) });
  });

  socket.on('joinRoom', ({ roomId, name, avatar, asSpectator }) => {
    const code = (roomId || '').toUpperCase().trim();
    const room = rooms[code];
    if (!room) { socket.emit('joinError', { message: 'Room not found. Check the code!' }); return; }
    if (room.players.length >= room.settings.maxPlayers) {
      socket.emit('joinError', { message: 'Room is full! (max ' + room.settings.maxPlayers + ')' }); return;
    }

    socket.join(code);
    socket.roomId = code;

    let player;
    if (asSpectator) {
      player = addPlayer(room, socket.id, name, avatar);
      player.isSpectator = true;
      room.players = room.players.filter(p => p.id !== socket.id);
      room.spectators.push(player);
    } else {
      player = addPlayer(room, socket.id, name, avatar);
      // If joining mid-game, mark as late joiner (they wait for next round to draw)
      if (room.state !== 'waiting') {
        player.lateJoin = true;
      }
    }

    socket.emit('roomJoined', { player, room: getRoomData(room) });
    socket.to(code).emit('playerJoined', { player, players: room.players, spectators: room.spectators });
  });

  socket.on('joinRandom', ({ name, avatar }) => {
    // Find a waiting matchmaking room (including ones in grace period with 0 players)
    let room = Object.values(rooms).find(r =>
      r.state === 'waiting' &&
      r.isMatchmaking === true &&
      r.players.length < r.settings.maxPlayers
    );

    const isNewRoom = !room;
    if (!room) {
      const id = createRoom();
      room = rooms[id];
      room.isMatchmaking = true;
      room.host = socket.id;
      room.mmStartTime = Date.now(); // track when matchmaking started
    }

    // Cancel grace-period deletion timer if rejoining
    if (room._graceTimer) {
      clearTimeout(room._graceTimer);
      delete room._graceTimer;
    }

    const player = addPlayer(room, socket.id, name, avatar);
    socket.join(room.id);
    socket.roomId = room.id;
    if (room.players.length === 1) room.host = socket.id;

    socket.emit('roomJoined', { player, room: getRoomData(room) });
    socket.to(room.id).emit('playerJoined', { player, players: room.players });

    if (room.players.length >= 2) {
      // ── 2+ players: cancel solo timer, start 10s multiplayer countdown ──
      if (room.matchmakingTimer)   { clearTimeout(room.matchmakingTimer);   room.matchmakingTimer = null; }
      if (room.matchmakingCountdown) { clearInterval(room.matchmakingCountdown); room.matchmakingCountdown = null; }

      let secs = 10;
      io.to(room.id).emit('matchmakingUpdate', { players: room.players.length, needed: 2, countdown: secs, waiting: false });

      room.matchmakingCountdown = setInterval(() => {
        secs--;
        io.to(room.id).emit('matchmakingUpdate', { players: room.players.length, needed: 2, countdown: secs, waiting: false });
        if (secs <= 0) { clearInterval(room.matchmakingCountdown); room.matchmakingCountdown = null; }
      }, 1000);

      room.matchmakingTimer = setTimeout(() => {
        if (!rooms[room.id] || room.state !== 'waiting') return;
        room.isMatchmaking = false;
        startGame(room);
      }, 10000);

    } else {
      // ── 1 player: only start timers if NOT already running (prevents reset on reconnect) ──
      if (!room.matchmakingTimer) {
        room.mmStartTime = Date.now();
        const SOLO_WAIT = 30000;

        // Send initial countdown
        io.to(room.id).emit('matchmakingUpdate', { players: 1, needed: 2, countdown: 30, waiting: true });

        room.matchmakingCountdown = setInterval(() => {
          if (!rooms[room.id]) { clearInterval(room.matchmakingCountdown); return; }
          const elapsed = Date.now() - room.mmStartTime;
          const remaining = Math.max(0, Math.ceil((SOLO_WAIT - elapsed) / 1000));
          io.to(room.id).emit('matchmakingUpdate', {
            players: room.players.length,
            needed: 2,
            countdown: remaining,
            waiting: room.players.length < 2
          });
          if (remaining <= 0) { clearInterval(room.matchmakingCountdown); room.matchmakingCountdown = null; }
        }, 1000);

        room.matchmakingTimer = setTimeout(() => {
          if (!rooms[room.id] || room.state !== 'waiting') return;
          if (room.players.length === 0) { delete rooms[room.id]; return; } // nobody reconnected
          room.isMatchmaking = false;
          room.settings.rounds = 3;
          startGame(room);
        }, SOLO_WAIT);

      } else {
        // Timer already running — just send current remaining time to this (re)joining socket
        const elapsed = Date.now() - (room.mmStartTime || Date.now());
        const remaining = Math.max(0, Math.ceil((30000 - elapsed) / 1000));
        socket.emit('matchmakingUpdate', { players: room.players.length, needed: 2, countdown: remaining, waiting: true });
      }
    }
  });

  // CRITICAL: When page reloads after game starts, new socket must rejoin room
  socket.on('rejoinGame', ({ roomId, name, avatar }) => {
    const code = (roomId || '').toUpperCase().trim();
    const room = rooms[code];
    if (!room) { socket.emit('rejoinError', { message: 'Room expired or not found' }); return; }

    socket.join(code);
    socket.roomId = code;

    // Check if player with same name already exists (reconnect)
    let player = room.players.find(p => p.name === name);
    if (player) {
      // Update their socket id to the new one
      const oldId = player.id;
      player.id = socket.id;
      // Update host if needed
      if (room.host === oldId) room.host = socket.id;
      // Update drawerOrder
      const di = room.drawerOrder.indexOf(oldId);
      if (di !== -1) room.drawerOrder[di] = socket.id;
    } else {
      // New player joining mid-game
      if (room.players.length >= room.settings.maxPlayers) {
        socket.emit('rejoinError', { message: 'Room is full!' }); return;
      }
      player = addPlayer(room, socket.id, name, avatar);
      player.lateJoin = true;
    }

    // Send current game state so they can sync up
    const drawer = room.players.find(p => p.isDrawing);
    socket.emit('gameRejoined', {
      player,
      room: getRoomData(room),
      state: room.state,
      round: room.currentRound,
      totalRounds: room.settings.rounds,
      drawer: drawer ? { id: drawer.id, name: drawer.name, avatar: drawer.avatar } : null,
      players: room.players,
      hint: room.currentWord ? hintMask(room.currentWord, room.hintsRevealed) : null,
      timeLeft: room.timeLeft,
      totalTime: room.totalTime,
      drawStrokes: room.drawStrokes,
      isDrawer: drawer?.id === socket.id,
      word: drawer?.id === socket.id ? room.currentWord : null,
    });

    // Tell others this player is back
    socket.to(code).emit('playerJoined', { player, players: room.players });
  });

  socket.on('startGame', () => {
    const room = rooms[socket.roomId];
    if (!room) return;
    if (room.host !== socket.id) { socket.emit('gameError', { message: 'Only the host can start' }); return; }
    if (room.players.length < 2) { socket.emit('gameError', { message: 'Need at least 2 players' }); return; }
    startGame(room);
  });

  socket.on('chooseWord', ({ word }) => {
    const room = rooms[socket.roomId];
    if (!room || room.state !== 'choosing') return;
    const player = room.players.find(p => p.id === socket.id);
    if (!player?.isDrawing || !room.wordChoices.includes(word)) return;
    wordChosen(room, word);
  });

  socket.on('draw', (data) => {
    const room = rooms[socket.roomId];
    if (!room || room.state !== 'drawing') return;
    const player = room.players.find(p => p.id === socket.id);
    if (!player?.isDrawing) return;
    const stamped = { ...data, t: Date.now() - (room.roundStartTime || Date.now()) };
    room.drawStrokes.push(stamped);
    socket.to(socket.roomId).emit('draw', data);
  });

  socket.on('clearCanvas', () => {
    const room = rooms[socket.roomId];
    if (!room || room.state !== 'drawing') return;
    const player = room.players.find(p => p.id === socket.id);
    if (!player?.isDrawing) return;
    room.drawStrokes = [{ type: 'clear', t: 0 }];
    io.to(socket.roomId).emit('clearCanvas');
  });

  socket.on('guess', ({ text }) => {
    const room = rooms[socket.roomId];
    if (!room || !text) return;
    const player = getPlayer(room, socket.id);
    if (!player) return;

    // Block drawer from revealing word in chat
    if (player.isDrawing) {
      socket.emit('chatMessage', { system: true, text: '🤫 You cannot chat while drawing!', type: 'warn' });
      return;
    }

    const result = checkGuess(room, socket.id, text);

    if (result === 'ignore') return;

    if (result?.correct) {
      socket.emit('correctGuess', { score: result.score, streak: result.streak, firstBonus: result.firstBonus });
      io.to(socket.roomId).emit('chatMessage', {
        system: true,
        text: `🎉 ${player.name} guessed it! (+${result.score}pts${result.streak > 1 ? ` 🔥x${result.streak}` : ''})`,
        type: 'correct'
      });
      broadcastPlayers(room);
    } else if (result === 'close') {
      socket.emit('chatMessage', { system: true, text: `🌡️ So close! Keep trying...`, type: 'close' });
      io.to(socket.roomId).emit('chatMessage', { sender: player.name, text: '...', playerId: socket.id, type: 'guess' });
    } else {
      io.to(socket.roomId).emit('chatMessage', { sender: player.name, text, playerId: socket.id, type: 'guess' });
    }
  });

  socket.on('chatMessage', ({ text }) => {
    const room = rooms[socket.roomId];
    if (!room || !text) return;
    const player = getPlayer(room, socket.id);
    if (!player) return;
    // Only allow chat in non-drawing state or for spectators
    if (room.state === 'drawing' && !player.isSpectator) {
      // This goes through guess flow - ignore raw chat
      return;
    }
    io.to(socket.roomId).emit('chatMessage', { sender: player.name, text: text.substring(0, 120), playerId: socket.id, type: 'chat' });
  });

  socket.on('usePowerUp', ({ type }) => {
    const room = rooms[socket.roomId];
    if (!room || room.state !== 'drawing') return;
    const player = room.players.find(p => p.id === socket.id);
    if (!player || player.isDrawing || !player.powerUps[type] || player.powerUps[type] <= 0) return;

    player.powerUps[type]--;

    if (type === 'revealLetter') {
      revealHint(room);
      io.to(socket.roomId).emit('chatMessage', { system: true, text: `🔍 ${player.name} revealed a letter!`, type: 'powerup' });
    } else if (type === 'timeWarp') {
      room.timeLeft = Math.min(room.timeLeft + 15, room.totalTime);
      io.to(socket.roomId).emit('timerUpdate', { timeLeft: room.timeLeft, totalTime: room.totalTime });
      io.to(socket.roomId).emit('chatMessage', { system: true, text: `⏰ ${player.name} warped time! +15s`, type: 'powerup' });
    } else if (type === 'bomb') {
      room.drawStrokes = [{ type: 'clear', t: Date.now() - room.roundStartTime }];
      io.to(socket.roomId).emit('clearCanvas');
      io.to(socket.roomId).emit('chatMessage', { system: true, text: `💣 ${player.name} dropped a BOMB! Canvas cleared!`, type: 'powerup' });
    }

    socket.emit('powerUpUsed', { type, remaining: player.powerUps });
  });

  socket.on('reaction', ({ emoji }) => {
    const room = rooms[socket.roomId];
    if (!room) return;
    const player = getPlayer(room, socket.id);
    io.to(socket.roomId).emit('reaction', { emoji, name: player?.name || 'Someone' });
  });

  socket.on('updateSettings', (settings) => {
    const room = rooms[socket.roomId];
    if (!room || room.host !== socket.id || room.state !== 'waiting') return;
    Object.assign(room.settings, settings);
    io.to(socket.roomId).emit('settingsUpdated', room.settings);
  });

  socket.on('kickPlayer', ({ playerId }) => {
    const room = rooms[socket.roomId];
    if (!room || room.host !== socket.id) return;
    const target = io.sockets.sockets.get(playerId);
    if (target) {
      target.emit('kicked', { reason: 'You were kicked by the host' });
      target.leave(socket.roomId);
    }
    room.players = room.players.filter(p => p.id !== playerId);
    io.to(socket.roomId).emit('playerLeft', { playerId, players: room.players });
  });

  socket.on('requestReplay', () => {
    // Allow replay of last round strokes - sent on roundEnd already
  });

  socket.on('disconnect', () => {
    const room = rooms[socket.roomId];
    if (!room) return;

    const wasDrawing = room.players.find(p => p.id === socket.id)?.isDrawing;
    room.players = room.players.filter(p => p.id !== socket.id);
    room.spectators = room.spectators.filter(p => p.id !== socket.id);

    if (room.players.length === 0 && room.spectators.length === 0) {
      if (room.isMatchmaking && room.matchmakingTimer) {
        // Keep room + matchmaking timers alive; give mobile 15s to reconnect
        room._graceTimer = setTimeout(() => {
          const r = rooms[socket.roomId];
          if (r && r.players.length === 0) {
            if (r.matchmakingTimer)   clearTimeout(r.matchmakingTimer);
            if (r.matchmakingCountdown) clearInterval(r.matchmakingCountdown);
            clearAllTimers(r);
            delete rooms[socket.roomId];
          }
        }, 15000);
      } else {
        clearAllTimers(room);
        if (room.matchmakingTimer)   clearTimeout(room.matchmakingTimer);
        if (room.matchmakingCountdown) clearInterval(room.matchmakingCountdown);
        delete rooms[socket.roomId];
      }
      return;
    }

    if (room.host === socket.id && room.players.length > 0) {
      room.host = room.players[0].id;
      io.to(room.host).emit('youAreHost');
    }

    io.to(socket.roomId).emit('playerLeft', { playerId: socket.id, players: room.players });

    if (wasDrawing && (room.state === 'drawing' || room.state === 'choosing')) {
      endRound(room);
    }

    if (room.players.length < 1 && room.state !== 'waiting' && room.state !== 'ended') {
      clearAllTimers(room);
      room.state = 'waiting';
      io.to(socket.roomId).emit('gameAborted', { reason: 'Not enough players to continue' });
    }
  });
});

server.listen(PORT, '0.0.0.0', () => {
  console.log(`🎨 Drawable running at http://localhost:${PORT}`);
});