const express = require('express');
const cors = require('cors');
const bodyParser = require('body-parser');
const bcrypt = require('bcrypt');
const { body, validationResult } = require('express-validator');
const morgan = require('morgan');
const timeout = require('connect-timeout');
const app = express();
const PORT = 3000;
app.use(cors({
    origin: 'http://your-frontend-domain.com',
    methods: ['GET', 'POST'],
    allowedHeaders: ['Content-Type']
}));
app.use(bodyParser.json());
app.use(morgan('combined'));
app.use(timeout('5s'));

let users = []; // 应该替换为实际的数据库
app.post('/api/register', [
    body('username').notEmpty().withMessage('用户名不能为空'),
    body('password').notEmpty().withMessage('密码不能为空'),
    body('confirm_password').custom((value, { req }) => {
        if (value !== req.body.password) {
            throw new Error('密码不匹配');
        }
        return true;
    })

], async (req, res) => {
    const errors = validationResult(req);
    if (!errors.isEmpty()) {
        return res.status(400).json({ errors: errors.array() });
    }
    
    const { username, password } = req.body;
    const existingUser = users.find(user => user.username === username);
    if (existingUser) {
        return res.status(400).send('用户名已被注册');
    }

    const hashedPassword = await bcrypt.hash(password, 10);
    users.push({ username, password: hashedPassword });
    res.status(201).send('注册成功');
});

app.use((err, req, res, next) => {
    console.error(err.stack);
    res.status(500).send('服务器内部错误');
});
app.listen(PORT, () => {
    console.log(`Server is running on http://localhost:${PORT}`);
});