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

// 引入数据库模型
const { ApiUser } = require('../models')

// 引入认证中间件
const { authenticateJWT } = require('../middleware/auth')

/**
 * @swagger
 * components:
 *   schemas:
 *     LoginRequest:
 *       type: object
 *       required:
 *         - username
 *         - password
 *       properties:
 *         username: 
 *           type: string
 *           description: 用户名
 *         password: 
 *           type: string
 *           description: 密码
 *     LoginResponse:
 *       type: object
 *       properties:
 *         success: 
 *           type: boolean
 *         message: 
 *           type: string
 *         token: 
 *           type: string
 *         user: 
 *           type: object
 *           properties:
 *             id: 
 *               type: integer
 *             username: 
 *               type: string
 *             email: 
 *               type: string
 *             user_type: 
 *               type: string
 *             status: 
 *               type: string
 */

// 从环境变量或配置中获取JWT密钥
const JWT_SECRET = process.env.JWT_SECRET || 'your_jwt_secret_key'
const JWT_EXPIRES_IN = process.env.JWT_EXPIRES_IN || '24h'

// 验证模式
const loginSchema = Joi.object({
  username: Joi.string().required(),
  password: Joi.string().required()
})

// 生成JWT令牌
const generateToken = (user) => {
  return jwt.sign(
    {
      id: user.id,
      username: user.username,
      email: user.email,
      user_type: user.user_type
    },
    JWT_SECRET,
    {
      expiresIn: JWT_EXPIRES_IN
    }
  )
}

/**
 * @swagger
 * /api/auth/login:
 *   post:
 *     summary: 用户登录
 *     tags: [认证管理]
 *     requestBody:
 *       required: true
 *       content:
 *         application/json:
 *           schema:
 *             $ref: '#/components/schemas/LoginRequest'
 *     responses:
 *       200:
 *         description: 登录成功
 *         content:
 *           application/json:
 *             schema:
 *               $ref: '#/components/schemas/LoginResponse'
 *       400:
 *         description: 参数验证失败或用户名密码错误
 *       401:
 *         description: 未授权或用户被禁用
 *       500:
 *         description: 服务器内部错误
 */
// 用户登录
router.post('/login', async (req, res) => {
  try {
    // 参数验证
    const { error, value } = loginSchema.validate(req.body)
    if (error) {
      return res.status(400).json({
        success: false,
        message: '参数验证失败',
        details: error.details[0].message
      })
    }
    
    const { username, password } = value
    
    // 查找用户
    const user = await ApiUser.findOne({
      where: {
        [ApiUser.sequelize.Op.or]: [
          { username },
          { email: username }
        ]
      }
    })
    
    // 检查用户是否存在以及密码是否正确
    if (!user || !(await bcrypt.compare(password, user.password_hash))) {
      return res.status(401).json({
        success: false,
        message: '用户名或密码错误'
      })
    }
    
    // 检查用户状态
    if (user.status !== 'active') {
      return res.status(401).json({
        success: false,
        message: '用户账号已被禁用'
      })
    }
    
    // 生成JWT令牌
    const token = generateToken(user)
    
    // 准备返回的用户信息（不包含敏感数据）
    const userInfo = {
      id: user.id,
      username: user.username,
      email: user.email,
      user_type: user.user_type,
      status: user.status
    }
    
    res.json({
      success: true,
      message: '登录成功',
      token,
      user: userInfo
    })
  } catch (error) {
    console.error('用户登录失败:', error)
    res.status(500).json({
      success: false,
      message: '登录失败，请稍后再试'
    })
  }
})

/**
 * @swagger
 * /api/auth/me:
 *   get:
 *     summary: 获取当前用户信息
 *     tags: [认证管理]
 *     security:
 *       - bearerAuth: []
 *     responses:
 *       200:
 *         description: 获取成功
 *         content:
 *           application/json:
 *             schema:
 *               type: object
 *               properties:
 *                 success: 
 *                   type: boolean
 *                 data: 
 *                   type: object
 *                   properties:
 *                     id: 
 *                       type: integer
 *                     username: 
 *                       type: string
 *                     email: 
 *                       type: string
 *                     user_type: 
 *                       type: string
 *                     status: 
 *                       type: string
 *                     createdAt: 
 *                       type: string
 *                       format: date-time
 *                     updatedAt: 
 *                       type: string
 *                       format: date-time
 *       401:
 *         description: 未授权
 *       500:
 *         description: 服务器内部错误
 */
// 获取当前用户信息
router.get('/me', authenticateJWT, async (req, res) => {
  try {
    const userId = req.user.id
    
    // 根据ID查找用户
    const user = await ApiUser.findByPk(userId, {
      attributes: {
        exclude: ['password_hash'] // 排除密码哈希等敏感信息
      }
    })
    
    if (!user) {
      return res.status(404).json({
        success: false,
        message: '用户不存在'
      })
    }
    
    res.json({
      success: true,
      data: user
    })
  } catch (error) {
    console.error('获取用户信息失败:', error)
    res.status(500).json({
      success: false,
      message: '获取用户信息失败'
    })
  }
})

/**
 * @swagger
 * /api/auth/logout:
 *   post:
 *     summary: 用户登出
 *     tags: [认证管理]
 *     security:
 *       - bearerAuth: []
 *     responses:
 *       200:
 *         description: 登出成功
 *         content:
 *           application/json:
 *             schema:
 *               type: object
 *               properties:
 *                 success: 
 *                   type: boolean
 *                 message: 
 *                   type: string
 *       401:
 *         description: 未授权
 *       500:
 *         description: 服务器内部错误
 */
// 用户登出
router.post('/logout', authenticateJWT, async (req, res) => {
  try {
    // 注意：JWT是无状态的，服务器端无法直接使token失效
    // 登出操作主要由客户端完成，如删除本地存储的token
    // 这里只返回成功信息
    
    res.json({
      success: true,
      message: '登出成功'
    })
  } catch (error) {
    console.error('用户登出失败:', error)
    res.status(500).json({
      success: false,
      message: '登出失败，请稍后再试'
    })
  }
})

module.exports = router