async function handleSignin(c: Context<{ Bindings: Env }>): Promise<Response> {
  try {
    const { username, password } = await c.req.json();
    // 查询用户是否存在
    const user = await c.env.DB.prepare('SELECT * FROM users WHERE username = ?').bind(username).first();
    // 如果用户存在，返回错误信息
    if (user) {
        return c.json({ error: 'User already exists' }, 400);
    } else {
        // 如果用户不存在，则创建用户
        // 密码加密
        // const hashedPassword = await bcrypt.hash(password, 10);
        const query = `INSERT INTO users (username, password, id) VALUES (?, ?, ?)`;
        const params = [username, password, Date.now()];
        const result = await c.env.DB.prepare(query).bind(...params).run();
        return c.json({ message: 'User created successfully' });
    }
  } catch (error: any) {
    return c.json({ error: error.message }, 500);
  }
}