server.js

const express = require('express');
const http = require('http');
const { Server } = require('socket.io');
const path = require('path');
const crypto = require('crypto');
const fs = require('fs');
const { fork } = require('child_process');
const { AIEngine } = require('./ai/inference');
const { loadGames } = require('./ai/train');
const { pullGames, pushGames, pushWeights, pullWeights } = require('./ai/persist');

let DATA_DIR;
if (process.env.DATA_DIR) {
  DATA_DIR = process.env.DATA_DIR;
  fs.mkdirSync(DATA_DIR, { recursive: true });
  console.log('Using configured storage ' + DATA_DIR);
} else try {
  fs.accessSync('/data', fs.constants.W_OK);
  DATA_DIR = '/data';
  console.log('Using persistent storage bucket /data');
} catch {
  DATA_DIR = path.join(__dirname, 'ai');
  console.log('Using local storage ' + DATA_DIR);
}
const MODEL_PATH = path.join(DATA_DIR, 'model_weights.json');
const GIT_MODEL_PATH = path.join(__dirname, 'ai', 'model_weights.json');
let HUMAN_GAMES_PATH = path.join(DATA_DIR, 'human_games.jsonl');
let aiEngine = null;
async function loadAIEngine() {
  if (process.env.HF_TOKEN) await pullWeights(MODEL_PATH);
  const wp = fs.existsSync(MODEL_PATH) ? MODEL_PATH : GIT_MODEL_PATH;
  if (fs.existsSync(wp)) {
    aiEngine = new AIEngine(wp);
    const size = fs.statSync(wp).size;
    console.log('AI engine loaded from ' + path.basename(wp) + ' (' + size + ' bytes)');
  } else {
    console.log('No model weights found — AI mode unavailable');
  }
}

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

app.use(express.json());
app.use(express.static(path.join(__dirname, 'public')));

// ─── Train API ─────────────────────────────────────────────────────────────────
let trainingStatus = { running: false, lastRun: null, error: null, gamesUsed: 0, loss: null };
let gamesSinceLastTrain = 0;
const AUTO_TRAIN_THRESHOLD = 5;
const IDLE_SELF_PLAY_ENABLED = process.env.IDLE_SELF_PLAY_ENABLED !== '0';
const IDLE_SELF_PLAY_DELAY_MS = parseInt(process.env.IDLE_SELF_PLAY_DELAY_MS || '60000', 10);
const IDLE_SELF_PLAY_INTERVAL_MS = parseInt(process.env.IDLE_SELF_PLAY_INTERVAL_MS || '15000', 10);
const IDLE_SELF_PLAY_BATCH_SIZE = parseInt(process.env.IDLE_SELF_PLAY_BATCH_SIZE || '2', 10);
const SELF_PLAY_RANDOM_RATE = parseFloat(process.env.SELF_PLAY_RANDOM_RATE || '0.15');
let connectedSockets = 0;
let lastUserActivityAt = Date.now();
let selfPlayRunning = false;
let selfPlayGamesGenerated = 0;

function markUserActivity() {
  lastUserActivityAt = Date.now();
}

function runTraining() {
  if (trainingStatus.running) return;
  if (!fs.existsSync(HUMAN_GAMES_PATH)) return;

  // Ensure weights file exists in DATA_DIR (seed from git if needed)
  if (!fs.existsSync(MODEL_PATH) && fs.existsSync(GIT_MODEL_PATH)) {
    fs.copyFileSync(GIT_MODEL_PATH, MODEL_PATH);
    console.log('Seeded model weights from ' + GIT_MODEL_PATH + ' to ' + MODEL_PATH);
  }

  trainingStatus.running = true;
  trainingStatus.error = null;

  const child = fork(path.join(__dirname, 'ai', 'train.js'), [
    HUMAN_GAMES_PATH, MODEL_PATH, '10'
  ], { stdio: 'pipe' });

  let stdout = '';
  child.stdout.on('data', d => { stdout += d; process.stdout.write(`[train] ${d}`); });
  child.stderr.on('data', d => process.stderr.write(`[train] ${d}`));

  child.on('exit', async (code) => {
    trainingStatus.running = false;
    if (code === 0) {
      try {
        const match = stdout.match(/TRAIN_RESULT games=(\d+) loss=([\d.]+)/);
        if (match) {
          trainingStatus.gamesUsed = parseInt(match[1]);
          trainingStatus.loss = parseFloat(match[2]);
        }
        trainingStatus.lastRun = Date.now();
        gamesSinceLastTrain = 0;
        if (fs.existsSync(MODEL_PATH) && aiEngine) aiEngine = new AIEngine(MODEL_PATH);
        // Push to Hub for persistence
        await Promise.all([
          pushGames(HUMAN_GAMES_PATH),
          pushWeights(MODEL_PATH),
        ]);
        console.log('Training complete, AI engine reloaded');
      } catch (e) {
        trainingStatus.error = 'Reload failed: ' + e.message;
      }
    } else {
      trainingStatus.error = `Process exited with code ${code}`;
    }
  });
}

function saveTrainingGame(game, source = 'human') {
  if (!game || !Array.isArray(game.moves) || game.moves.length === 0) return false;
  const entry = JSON.stringify({ ...game, source, ts: game.ts || Date.now() }) + '\n';
  const tryWrite = (filePath) => { fs.appendFileSync(filePath, entry, 'utf-8'); return filePath; };
  let savedPath;
  try {
    savedPath = tryWrite(HUMAN_GAMES_PATH);
  } catch (e) {
    console.error('Failed to write to ' + HUMAN_GAMES_PATH + ':', e.message);
    if (DATA_DIR === '/data') {
      DATA_DIR = path.join(__dirname, 'ai');
      HUMAN_GAMES_PATH = path.join(DATA_DIR, 'human_games.jsonl');
      try {
        savedPath = tryWrite(HUMAN_GAMES_PATH);
        console.log('Fell back to ' + savedPath);
      } catch (e2) {
        console.error('Failed to save AI game to fallback:', e2.message);
        return false;
      }
    } else {
      return false;
    }
  }

  console.log(`${source} game saved to ${savedPath} (${game.moves.length} moves)`);
  gamesSinceLastTrain++;
  pushGames(HUMAN_GAMES_PATH).catch(() => {});
  if (gamesSinceLastTrain >= AUTO_TRAIN_THRESHOLD && !trainingStatus.running) {
    setImmediate(runTraining);
  }
  return true;
}

app.post('/api/train', (req, res) => {
  if (trainingStatus.running) {
    return res.json({ success: false, error: 'Training already in progress' });
  }
  if (!fs.existsSync(HUMAN_GAMES_PATH)) {
    return res.json({ success: false, error: 'No game data found' });
  }
  const games = loadGames(HUMAN_GAMES_PATH);
  if (games.length === 0) {
    return res.json({ success: false, error: 'No games recorded yet' });
  }
  res.json({ success: true, message: `Training started on ${games.length} games` });
  setImmediate(runTraining);
});

app.get('/api/train-status', (req, res) => {
  res.json({ ...trainingStatus, gamesSinceLastTrain, autoTrainThreshold: AUTO_TRAIN_THRESHOLD });
});

app.get('/api/game-count', (req, res) => {
  try {
    if (!fs.existsSync(HUMAN_GAMES_PATH)) return res.json({ count: 0 });
    const data = fs.readFileSync(HUMAN_GAMES_PATH, 'utf-8').trim();
    const count = data ? data.split('\n').filter(Boolean).length : 0;
    res.json({ count });
  } catch { res.json({ count: 0 }); }
});

app.get('/api/self-play-status', (req, res) => {
  res.json({
    enabled: IDLE_SELF_PLAY_ENABLED,
    running: selfPlayRunning,
    gamesGenerated: selfPlayGamesGenerated,
    connectedSockets,
    idleForMs: Date.now() - lastUserActivityAt,
    idleDelayMs: IDLE_SELF_PLAY_DELAY_MS,
    batchSize: IDLE_SELF_PLAY_BATCH_SIZE,
    randomRate: SELF_PLAY_RANDOM_RATE,
  });
});

// ─── Game State Factory ────────────────────────────────────────────────────────
const PLAYERS = [
  { symbol: 'X',        color: '#FF4757', label: 'X'        },
  { symbol: 'Circle',   color: '#2ED7F8', label: 'Circle'   },
  { symbol: 'Triangle', color: '#2ECC71', label: 'Triangle' },
  { symbol: 'Square',   color: '#FFD32A', label: 'Square'   },
];

function makeBoard() {
  // macroBoard[r][c] = null | player symbol (winner of that micro board)
  // microBoard[mr][mc][r][c] = null | player symbol
  const macroBoard = Array.from({ length: 3 }, () => Array(3).fill(null));
  const microBoard = Array.from({ length: 3 }, () =>
    Array.from({ length: 3 }, () =>
      Array.from({ length: 3 }, () => Array(3).fill(null))
    )
  );
  return { macroBoard, microBoard };
}

function checkLine(a, b, c) {
  return a && a === b && b === c ? a : null;
}

function checkWinner3x3(grid) {
  for (let i = 0; i < 3; i++) {
    const rw = checkLine(grid[i][0], grid[i][1], grid[i][2]);
    if (rw) return rw;
    const cw = checkLine(grid[0][i], grid[1][i], grid[2][i]);
    if (cw) return cw;
  }
  const d1 = checkLine(grid[0][0], grid[1][1], grid[2][2]);
  if (d1) return d1;
  const d2 = checkLine(grid[0][2], grid[1][1], grid[2][0]);
  if (d2) return d2;
  return null;
}

function isFull3x3(grid) {
  return grid.every(row => row.every(cell => cell !== null));
}

// Check for global line wins across the full 9x9 grid.
// Any 3 consecutive same-symbol cells in a straight line (horizontal, vertical,
// or diagonal) across ANY board boundary counts. Each matching trio awards the
// macro square that each of the three cells belongs to (if not already won).
function checkGlobalLines(microBoard, macroBoard) {
  // Build flat 9x9 — null out cells in owned boards so they don't contribute to new lines
  const flat = Array.from({ length: 9 }, () => Array(9).fill(null));
  for (let mr = 0; mr < 3; mr++)
    for (let mc = 0; mc < 3; mc++)
      for (let r = 0; r < 3; r++)
        for (let c = 0; c < 3; c++)
          flat[mr * 3 + r][mc * 3 + c] = microBoard[mr][mc][r][c];

  const winners = new Set();

  // Helper: test a trio of (row,col) positions; award their macro squares if matched
  function testTrio(r0, c0, r1, c1, r2, c2) {
    const w = checkLine(flat[r0][c0], flat[r1][c1], flat[r2][c2]);
    if (!w) return;
    const cells = [[r0,c0],[r1,c1],[r2,c2]];
    // Award unowned macro squares (lines through owned boards still count)
    cells.forEach(([r,c]) => {
      const mr = Math.floor(r/3), mc = Math.floor(c/3);
      if (!macroBoard[mr][mc]) winners.add(`${mr},${mc},${w}`);
    });
  }

  // All 9 full rows — every consecutive triple along each row
  for (let gr = 0; gr < 9; gr++)
    for (let sc = 0; sc <= 6; sc++)
      testTrio(gr, sc, gr, sc+1, gr, sc+2);

  // All 9 full columns — every consecutive triple along each column
  for (let gc = 0; gc < 9; gc++)
    for (let sr = 0; sr <= 6; sr++)
      testTrio(sr, gc, sr+1, gc, sr+2, gc);

  // All diagonals (top-left → bottom-right), consecutive triples
  for (let sr = 0; sr <= 6; sr++)
    for (let sc = 0; sc <= 6; sc++)
      testTrio(sr, sc, sr+1, sc+1, sr+2, sc+2);

  // All anti-diagonals (top-right → bottom-left), consecutive triples
  for (let sr = 0; sr <= 6; sr++)
    for (let sc = 2; sc < 9; sc++)
      testTrio(sr, sc, sr+1, sc-1, sr+2, sc-2);

  return winners; // set of "mr,mc,symbol"
}

function evaluateBoard(state) {
  const { microBoard, macroBoard } = state;

  // First, check standard micro-board wins
  for (let mr = 0; mr < 3; mr++) {
    for (let mc = 0; mc < 3; mc++) {
      if (!macroBoard[mr][mc]) {
        const w = checkWinner3x3(microBoard[mr][mc]);
        if (w) macroBoard[mr][mc] = w;
      }
    }
  }

  // Then apply global cross-board lines
  const globalWins = checkGlobalLines(microBoard, macroBoard);
  for (const entry of globalWins) {
    const [mr, mc, sym] = entry.split(',');
    if (!macroBoard[+mr][+mc]) {
      macroBoard[+mr][+mc] = sym;
    }
  }

  // Check macro winner
  const macroWinner = checkWinner3x3(macroBoard);
  if (macroWinner) return { winner: macroWinner, type: 'macro' };

  // All macro squares owned (each micro board won by someone) → majority
  const allOwned = macroBoard.flat().every(cell => cell !== null);
  if (allOwned || (() => {
    for (let mr = 0; mr < 3; mr++)
      for (let mc = 0; mc < 3; mc++)
        if (!isFull3x3(microBoard[mr][mc])) return false;
    return true;
  })()) {
    const counts = {};
    for (let mr = 0; mr < 3; mr++)
      for (let mc = 0; mc < 3; mc++) {
        const owner = macroBoard[mr][mc];
        if (owner) counts[owner] = (counts[owner] || 0) + 1;
      }
    if (Object.keys(counts).length === 0) return { winner: null, type: 'draw' };
    const topScore = Math.max(...Object.values(counts));
    const topPlayers = Object.keys(counts).filter(k => counts[k] === topScore);
    if (topPlayers.length === 1) return { winner: topPlayers[0], type: 'majority' };
    return { winner: null, type: 'draw' };
  }

  return null;
}

// ─── Room Management ───────────────────────────────────────────────────────────
const rooms = {};

function generateCode() {
  return crypto.randomBytes(3).toString('hex').toUpperCase();
}

function getRoomState(room) {
  return {
    players: room.players.map(p => ({ id: p.id, name: p.name, symbol: p.symbol, color: p.color })),
    board: room.board,
    currentTurn: room.currentTurn,
    started: room.started,
    gameOver: room.gameOver,
    winner: room.winner,
    winType: room.winType,
    hostId: room.hostId,
  };
}

function hasActiveRooms() {
  return Object.values(rooms).some(room => room.players.length > 0);
}

function isIdleForSelfPlay() {
  return IDLE_SELF_PLAY_ENABLED &&
    aiEngine &&
    !trainingStatus.running &&
    connectedSockets === 0 &&
    !hasActiveRooms() &&
    Date.now() - lastUserActivityAt >= IDLE_SELF_PLAY_DELAY_MS;
}

function chooseSelfPlayMove(board, symbol) {
  const valid = [];
  for (let mr = 0; mr < 3; mr++)
    for (let mc = 0; mc < 3; mc++)
      for (let r = 0; r < 3; r++)
        for (let c = 0; c < 3; c++)
          if (board.microBoard[mr][mc][r][c] === null)
            valid.push({ mr, mc, r, c });

  if (valid.length === 0) return null;
  if (Math.random() < SELF_PLAY_RANDOM_RATE) {
    return valid[Math.floor(Math.random() * valid.length)];
  }
  return aiEngine.getMove(board.macroBoard, board.microBoard, symbol);
}

function generateSelfPlayGame() {
  const board = makeBoard();
  const symbols = ['X', 'Circle'];
  const moves = [];
  let currentTurn = 0;
  let result = null;

  for (let ply = 0; ply < 81 && !result; ply++) {
    const symbol = symbols[currentTurn];
    const move = chooseSelfPlayMove(board, symbol);
    if (!move) break;
    if (board.microBoard[move.mr][move.mc][move.r][move.c] !== null) break;

    board.microBoard[move.mr][move.mc][move.r][move.c] = symbol;
    moves.push({ ...move, symbol });
    result = evaluateBoard(board);
    currentTurn = (currentTurn + 1) % symbols.length;
  }

  if (moves.length < 2) return null;
  return {
    moves,
    humanSymbol: null,
    policySymbols: symbols,
    winner: result ? result.winner : null,
  };
}

async function runIdleSelfPlayBatch() {
  if (selfPlayRunning || !isIdleForSelfPlay()) return;
  selfPlayRunning = true;
  let generated = 0;

  try {
    for (let i = 0; i < IDLE_SELF_PLAY_BATCH_SIZE; i++) {
      if (!isIdleForSelfPlay()) break;
      const game = generateSelfPlayGame();
      if (game && saveTrainingGame(game, 'self-play')) {
        generated++;
        selfPlayGamesGenerated++;
      }
      await new Promise(resolve => setImmediate(resolve));
    }
    if (generated > 0 && !trainingStatus.running) setImmediate(runTraining);
  } catch (e) {
    console.error('Idle self-play failed:', e.message);
  } finally {
    selfPlayRunning = false;
  }
}

// ─── Socket.io ────────────────────────────────────────────────────────────────
io.on('connection', (socket) => {
  connectedSockets++;
  markUserActivity();
  socket.use((packet, next) => {
    markUserActivity();
    next();
  });

  // ── Create Room ──
  socket.on('createRoom', ({ playerName }) => {
    const code = generateCode();
    const player = {
      id: socket.id,
      name: playerName || 'Host',
      ...PLAYERS[0],
    };
    rooms[code] = {
      code,
      hostId: socket.id,
      players: [player],
      board: makeBoard(),
      currentTurn: 0,
      started: false,
      gameOver: false,
      winner: null,
      winType: null,
    };
    socket.join(code);
    socket.roomCode = code;
    socket.emit('roomCreated', { code, state: getRoomState(rooms[code]) });
    systemMsg(code, `${player.name} created the room.`);
  });

  // ── Join Room ──
  socket.on('joinRoom', ({ code, playerName }) => {
    const room = rooms[code.toUpperCase()];
    if (!room) return socket.emit('error', 'Room not found.');
    if (room.started) return socket.emit('error', 'Game already started.');
    if (room.players.length >= 4) return socket.emit('error', 'Room is full.');

    const idx = room.players.length;
    const player = {
      id: socket.id,
      name: playerName || `Player ${idx + 1}`,
      ...PLAYERS[idx],
    };
    room.players.push(player);
    socket.join(code.toUpperCase());
    socket.roomCode = code.toUpperCase();
    socket.emit('joinedRoom', { code: code.toUpperCase(), state: getRoomState(room) });
    io.to(code.toUpperCase()).emit('roomUpdate', getRoomState(room));
    systemMsg(code.toUpperCase(), `${player.name} joined as ${player.symbol}.`);
  });

  // ── Start Game ──
  socket.on('startGame', () => {
    const room = rooms[socket.roomCode];
    if (!room || socket.id !== room.hostId) return;
    if (room.players.length < 2) return socket.emit('error', 'Need at least 2 players.');
    room.started = true;
    room.board = makeBoard();
    room.currentTurn = 0;
    io.to(room.code).emit('gameStarted', getRoomState(room));
    systemMsg(room.code, `Game started! ${room.players[0].name}'s turn.`);
  });

  // ── Make Move ──
  socket.on('makeMove', ({ mr, mc, r, c }) => {
    const room = rooms[socket.roomCode];
    if (!room || !room.started || room.gameOver) return;

    const playerIdx = room.players.findIndex(p => p.id === socket.id);
    if (playerIdx !== room.currentTurn) return socket.emit('error', 'Not your turn.');

    const cell = room.board.microBoard[mr][mc][r][c];
    if (cell !== null) return socket.emit('error', 'Cell occupied.');

    const player = room.players[playerIdx];
    room.board.microBoard[mr][mc][r][c] = player.symbol;

    // Track micro-board state before evaluation
    const prevMacro = room.board.macroBoard.map(row => [...row]);

    const result = evaluateBoard(room.board);

    // Notify micro-board wins
    for (let imr = 0; imr < 3; imr++) {
      for (let imc = 0; imc < 3; imc++) {
        if (!prevMacro[imr][imc] && room.board.macroBoard[imr][imc]) {
          const winner = room.board.macroBoard[imr][imc];
          const wp = room.players.find(p => p.symbol === winner);
          systemMsg(room.code, `${wp?.name || winner} won a micro-board!`);
        }
      }
    }

    if (result) {
      room.gameOver = true;
      room.winner = result.winner;
      room.winType = result.type;
      const wp = room.players.find(p => p.symbol === result.winner);
      if (result.type === 'draw') {
        systemMsg(room.code, "It's a draw!");
      } else if (result.type === 'majority') {
        systemMsg(room.code, `${wp?.name || result.winner} wins by majority!`);
      } else {
        systemMsg(room.code, `${wp?.name || result.winner} wins!`);
      }
      io.to(room.code).emit('boardUpdate', getRoomState(room));
      io.to(room.code).emit('gameOver', { winner: result.winner, winType: result.type, state: getRoomState(room) });
    } else {
      // Advance turn (skip players who have disconnected... simplified: cycle)
      room.currentTurn = (room.currentTurn + 1) % room.players.length;
      const nextPlayer = room.players[room.currentTurn];
      systemMsg(room.code, `${nextPlayer.name}'s turn.`);
      io.to(room.code).emit('boardUpdate', getRoomState(room));
    }
  });

  // ── Local Move (single device) ──
  socket.on('localMove', ({ mr, mc, r, c, players, board, currentTurn }) => {
    // Reconstruct and validate
    if (board.microBoard[mr][mc][r][c] !== null) {
      return socket.emit('localError', 'Cell occupied.');
    }
    const player = players[currentTurn];
    board.microBoard[mr][mc][r][c] = player.symbol;

    const prevMacro = board.macroBoard.map(row => [...row]);
    const result = evaluateBoard(board);

    const microWins = [];
    for (let imr = 0; imr < 3; imr++) {
      for (let imc = 0; imc < 3; imc++) {
        if (!prevMacro[imr][imc] && board.macroBoard[imr][imc]) {
          microWins.push({ mr: imr, mc: imc, winner: board.macroBoard[imr][imc] });
        }
      }
    }

    const nextTurn = result ? currentTurn : (currentTurn + 1) % players.length;
    socket.emit('localUpdate', { board, currentTurn: nextTurn, result, microWins });
  });

  // ── AI Move ──
  socket.on('requestAIMove', ({ board, aiSymbol }) => {
    if (!aiEngine) return socket.emit('error', 'AI engine not available');
    const move = aiEngine.getMove(board.macroBoard, board.microBoard, aiSymbol);
    socket.emit('aiMove', move);
  });

  // ── Save AI Game (for training) ──
  socket.on('saveAIGame', ({ moves, humanSymbol, winner }) => {
    if (!Array.isArray(moves) || moves.length === 0) return;
    saveTrainingGame({ moves, humanSymbol, winner }, 'human');
  });

  // ── Chat ──
  socket.on('chatMsg', ({ text }) => {
    const room = rooms[socket.roomCode];
    if (!room) return;
    const player = room.players.find(p => p.id === socket.id);
    if (!player) return;
    if (!text || text.trim().length === 0) return;
    io.to(room.code).emit('chatMsg', {
      type: 'player',
      name: player.name,
      symbol: player.symbol,
      color: player.color,
      text: text.trim().substring(0, 200),
      ts: Date.now(),
    });
  });

  // ── Restart ──
  socket.on('restartGame', () => {
    const room = rooms[socket.roomCode];
    if (!room || socket.id !== room.hostId) return;
    room.board = makeBoard();
    room.currentTurn = 0;
    room.gameOver = false;
    room.winner = null;
    room.winType = null;
    io.to(room.code).emit('gameStarted', getRoomState(room));
    systemMsg(room.code, 'Game restarted!');
  });

  // ── Disconnect ──
  socket.on('disconnect', () => {
    connectedSockets = Math.max(0, connectedSockets - 1);
    markUserActivity();
    const room = rooms[socket.roomCode];
    if (!room) return;
    const idx = room.players.findIndex(p => p.id === socket.id);
    if (idx === -1) return;
    const player = room.players[idx];
    systemMsg(room.code, `${player.name} disconnected.`);
    room.players.splice(idx, 1);

    if (room.players.length === 0) {
      delete rooms[socket.roomCode];
      return;
    }

    // Transfer host if needed
    if (socket.id === room.hostId) {
      room.hostId = room.players[0].id;
      systemMsg(room.code, `${room.players[0].name} is now the host.`);
    }

    // Adjust currentTurn
    if (room.currentTurn >= room.players.length) {
      room.currentTurn = 0;
    }

    io.to(room.code).emit('roomUpdate', getRoomState(room));
  });

  function systemMsg(code, text) {
    io.to(code).emit('chatMsg', {
      type: 'system',
      text,
      ts: Date.now(),
    });
  }
});

const PORT = process.env.PORT || 7860;
(async () => {
  try {
    if (process.env.HF_TOKEN) await pullGames(HUMAN_GAMES_PATH);
    await loadAIEngine();
  } catch (e) { console.error('Startup init error:', e.message); }
  server.listen(PORT, '0.0.0.0', () => {
    console.log(`Super TTT running on port ${PORT}`);
    if (IDLE_SELF_PLAY_ENABLED) {
      setInterval(runIdleSelfPlayBatch, IDLE_SELF_PLAY_INTERVAL_MS);
      console.log(`Idle self-play enabled after ${IDLE_SELF_PLAY_DELAY_MS}ms of inactivity`);
    }
  });
})();