Multiplayer mode: server, room tokens, docker setup, and client UI

server/db.js

@@ -0,0 +1,85 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const initSqlJs = require('sql.js');
+
+const DATA_DIR = path.join(__dirname, 'data');
+const DB_PATH = path.join(DATA_DIR, 'games.db');
+
+let db = null;
+
+async function init() {
+  if (!fs.existsSync(DATA_DIR)) {
+    fs.mkdirSync(DATA_DIR, { recursive: true });
+  }
+
+  const SQL = await initSqlJs();
+
+  if (fs.existsSync(DB_PATH)) {
+    const buf = fs.readFileSync(DB_PATH);
+    db = new SQL.Database(buf);
+  } else {
+    db = new SQL.Database();
+    db.run(`CREATE TABLE IF NOT EXISTS games (
+      id         TEXT PRIMARY KEY,
+      token      TEXT UNIQUE NOT NULL,
+      status     TEXT NOT NULL DEFAULT 'waiting',
+      board      TEXT NOT NULL DEFAULT 'null',
+      turn       TEXT NOT NULL DEFAULT 'X',
+      created_at TEXT NOT NULL,
+      updated_at TEXT NOT NULL
+    )`);
+    persist();
+  }
+}
+
+function createGame({ id, token }) {
+  const now = new Date().toISOString();
+  db.run(
+    `INSERT INTO games (id, token, status, board, turn, created_at, updated_at)
+     VALUES (?, ?, 'waiting', 'null', 'X', ?, ?)`,
+    [id, token, now, now]
+  );
+  persist();
+}
+
+function getGameByToken(token) {
+  const stmt = db.prepare(`SELECT * FROM games WHERE token = ?`);
+  stmt.bind([token]);
+  if (stmt.step()) {
+    const row = stmt.getAsObject();
+    stmt.free();
+    return row;
+  }
+  stmt.free();
+  return null;
+}
+
+function getGameById(id) {
+  const stmt = db.prepare(`SELECT * FROM games WHERE id = ?`);
+  stmt.bind([id]);
+  if (stmt.step()) {
+    const row = stmt.getAsObject();
+    stmt.free();
+    return row;
+  }
+  stmt.free();
+  return null;
+}
+
+function updateGame(id, { status, board, turn }) {
+  const now = new Date().toISOString();
+  db.run(
+    `UPDATE games SET status = ?, board = ?, turn = ?, updated_at = ? WHERE id = ?`,
+    [status, board, turn, now, id]
+  );
+  persist();
+}
+
+function persist() {
+  const data = db.export();
+  fs.writeFileSync(DB_PATH, Buffer.from(data));
+}
+
+module.exports = { init, createGame, getGameByToken, getGameById, updateGame, persist };