const sqlite3 = require('sqlite3').verbose();
const path = require('path');

const dbPath = path.resolve(__dirname, 'chat.db');
const db = new sqlite3.Database(dbPath);

// 用户表
db.run(`CREATE TABLE IF NOT EXISTS users (
  id TEXT PRIMARY KEY,
  token TEXT NOT NULL,
  last_active DATETIME DEFAULT CURRENT_TIMESTAMP
)`);

// 消息表
db.run(`CREATE TABLE IF NOT EXISTS messages (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  sender_id TEXT NOT NULL,
  receiver_id TEXT,
  group_id TEXT,
  content TEXT NOT NULL,
  is_withdrawn BOOLEAN DEFAULT 0,
  timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
)`);

// 群组表
db.run(`CREATE TABLE IF NOT EXISTS groups (
  id TEXT PRIMARY KEY,
  name TEXT NOT NULL
)`);

// 群组成员表
db.run(`CREATE TABLE IF NOT EXISTS group_members (
  group_id TEXT NOT NULL,
  user_id TEXT NOT NULL,
  FOREIGN KEY(group_id) REFERENCES groups(id),
  FOREIGN KEY(user_id) REFERENCES users(id)
)`);

module.exports = db;