const express = require('express')
const cors = require('cors')
const helmet = require('helmet')
const morgan = require('morgan')
const rateLimit = require('express-rate-limit')
const compression = require('compression')
const path = require('path')
require('dotenv').config()

// 数据库连接
const { testConnection, syncModels } = require('./models')

// 导入Swagger配置
const { specs, swaggerUi } = require('./config/swagger')

const app = express()

// 中间件配置
app.use(helmet()) // 安全头
app.use(cors()) // 跨域
app.use(compression()) // 压缩
app.use(morgan('combined')) // 日志
app.use(express.json({ limit: '10mb' }))
app.use(express.urlencoded({ extended: true, limit: '10mb' }))

// 限流
const limiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 分钟
  max: 100, // 限制每个IP最多100个请求
  message: {
    success: false,
    message: '请求过于频繁，请稍后重试'
  }
})
app.use('/api', limiter)

// 健康检查
app.get('/health', (req, res) => {
  res.json({
    success: true,
    message: '服务运行正常',
    timestamp: new Date().toISOString(),
    version: process.env.npm_package_version || '1.0.0'
  })
})

// 配置Swagger UI
app.use('/swagger', swaggerUi.serve, swaggerUi.setup(specs, {
  explorer: true,
  customCss: '.swagger-ui .topbar { background-color: #3B82F6; }',
  customSiteTitle: 'NiuMall API 文档'
}))

// 提供Swagger JSON文件
app.get('/api-docs-json', (req, res) => {
  res.setHeader('Content-Type', 'application/json')
  res.send(specs)
})

const PORT = process.env.PORT || 4330

const startServer = async () => {
  try {
    // 测试数据库连接
    const dbConnected = await testConnection();
    if (!dbConnected) {
      console.error('❌ 数据库连接失败，服务器启动终止');
      process.exit(1);
    }
    
    // 同步数据库模型
    await syncModels();
    
    app.listen(PORT, () => {
      console.log(`🚀 服务器启动成功`)
      console.log(`📱 运行环境: ${process.env.NODE_ENV || 'development'}`)
      console.log(`🌐 访问地址: http://localhost:${PORT}`)
      console.log(`📊 健康检查: http://localhost:${PORT}/health`)
      console.log(`📚 API文档: http://localhost:${PORT}/swagger`)
      console.log(`📄 API文档JSON: http://localhost:${PORT}/api-docs-json`)
    })
  } catch (error) {
    console.error('❌ 服务器启动失败:', error)
    process.exit(1)
  }
}

startServer()

// API 路由
app.use('/api/auth', require('./routes/auth'))
app.use('/api/users', require('./routes/users'))
app.use('/api/orders', require('./routes/orders'))
app.use('/api/payments', require('./routes/payments'))