const express = require('express');
const bcrypt = require('bcryptjs');
const jwt = require('jsonwebtoken');
const router = express.Router();

const authMiddleware = require('../middleware/authMiddleware');

const User = require('../models/User');
const Logs = require('../libs/logs');

// 注册
router.post('/register', async (req, res) => {
  const { username, password } = req.body;
  User.findOne({ username })
  .then(existing => {
    if (existing) {
      return Promise.reject(new Error('USER_EXISTS'));
    }
    return bcrypt.hash(password, 10);
  })
  .then(hashedPassword => {
    const user = new User({ username, password: hashedPassword });
    return user.save();
  })
  .then(() => {
    res.sendSuccess('注册成功');
  })
  .catch(err => {
    Logs.errDev('注册失败:', err);
    if (err.message === 'USER_EXISTS') {
      return res.badRequest('用户已存在');
    }
    res.badRequest(err.message);
  });
});

// 登录 - 支持原路径 /login 和 mock 服务路径 /login
router.post('/login', async (req, res) => {
  const { username, password } = req.body;
  User.findOne({ username })
  .then(user => {
    if (!user) {
      return Promise.reject(new Error('USER_NOT_FOUND'));
    }
    return Promise.all([
      bcrypt.compare(password, user.password),
      Promise.resolve(user),
    ]);
  })
  .then(([isMatch, user]) => {
    if (!isMatch) {
      return Promise.reject(new Error('PASSWORD_ERROR'));
    }
    return user;
  })
  .then(user => {
    // 签发 Access Token 和 Refresh Token
    const accessToken = jwt.sign({ userId: user._id }, process.env.JWT_SECRET, { expiresIn: '30m' });
    const refreshToken = jwt.sign({ userId: user._id }, process.env.JWT_SECRET, { expiresIn: '7d' });

    // 设置 refresh token 到 cookie
    res.cookie('jwt', refreshToken, {
      httpOnly: true,
      secure: true,
      sameSite: 'none',
      maxAge: 7 * 24 * 60 * 60 * 1000 // 7天
    });

    // 返回格式与前端期望一致
    res.sendSuccess({
      accessToken: accessToken,
      uid: user._id.toString(),
      username: user.username,
      roles: user.roles ?? ['user'],
    });

  })
  .catch(err => {
    Logs.errDev('登录失败:', err);
    if (err.message === 'USER_NOT_FOUND') {
      return res.badRequest('用户不存在');
    }
    if (err.message === 'PASSWORD_ERROR') {
      return res.badRequest('密码错误');
    }
    res.badRequest(err.message);
  });

});

// 刷新 Token - 支持 Vben Admin 的 /refresh 路径
router.post('/refresh', async (req, res) => {
  const refreshToken = req.cookies.jwt;

  if (!refreshToken) {
    return res.unauthorized('无效的刷新token');
  }
  const decoded = jwt.verify(refreshToken, process.env.JWT_SECRET);
  User.findById(decoded.userId)
  .then(user => {
    if (!user) {
      return Promise.reject(new Error('USER_NOT_FOUND'));
    }

    // 签发新的 Access Token
    const newAccessToken = jwt.sign({ userId: user._id }, process.env.JWT_SECRET, { expiresIn: '30m' });

    // 按照Vben Admin期望的格式返回
    res.send(newAccessToken);
  })
  .catch(err => {
    Logs.errDev('刷新Token失败:', err);
    res.clearCookie('jwt');
    if (err.message === 'USER_NOT_FOUND') {
      return res.unauthorized('用户不存在');
    }
    res.unauthorized(err.message);
  });
});


// 用户信息 - 支持 mock 服务的 /info 路径
router.get('/info', authMiddleware, async (req, res) => {
  User.findById(req.userId).select('-password')
  .then(user => {
    if (!user) {
      return Promise.reject(new Error('USER_NOT_FOUND'));
    }

    const userInfo = {
      uid: user._id.toString(),
      username: user.username,
      roles: user.roles ?? ['user'],
    };

    res.sendSuccess(userInfo);

  })
  .catch(err => {
    Logs.errDev('获取用户信息错误:', err);
    if (err.message === 'USER_NOT_FOUND') {
      return res.notFound('用户不存在');
    }
    res.serverError(err.message);
  });
});

// 权限码 - 支持 mock 服务的 /codes 路径
router.get('/codes', authMiddleware, async (req, res) => {
  try {
    // 返回所有功能的权限码
    const codes = [
      'dashboard',
      'dashboard:analysis',
      'dashboard:workbench',
      'system',
      'system:account',
      'system:account:settings',
      'system:role',
      'system:menu',
      'system:dept',
    ];
    res.sendSuccess(codes);
  }
  catch (err) {
    Logs.errDev('获取权限码错误:', err);
    res.serverError(err.message);
  }
});

module.exports = router;