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 swaggerJsdoc = require('swagger-jsdoc')
const swaggerUi = require('swagger-ui-express')
require('dotenv').config()

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

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' }))

// Swagger 配置
const swaggerOptions = {
  definition: {
    openapi: '3.0.0',
    info: {
      title: '活牛采购智能数字化系统 API',
      version: '1.0.0',
      description: '活牛采购标准化操作流程系统接口文档',
      contact: {
        name: 'API支持',
        email: 'support@niumall.com'
      }
    },
    servers: [
      {
        url: 'http://localhost:4330/api',
        description: '开发环境'
      },
      {
        url: 'https://wapi.yunniushi.cn/api',
        description: '生产环境'
      }
    ],
    components: {
      securitySchemes: {
        BearerAuth: {
          type: 'http',
          scheme: 'bearer',
          bearerFormat: 'JWT'
        }
      },
      schemas: {
        ApiResponse: {
          type: 'object',
          properties: {
            success: { type: 'boolean', description: '请求是否成功' },
            message: { type: 'string', description: '提示信息' },
            data: { type: 'object', description: '响应数据' },
            timestamp: { type: 'string', format: 'date-time', description: '时间戳' }
          }
        },
        PaginationParams: {
          type: 'object',
          properties: {
            page: { type: 'integer', description: '当前页码' },
            limit: { type: 'integer', description: '每页数量' },
            sort: { type: 'string', description: '排序字段' },
            order: { type: 'string', enum: ['asc', 'desc'], description: '排序方向' }
          }
        },
        PaginatedResponse: {
          type: 'object',
          properties: {
            items: { type: 'array', description: '数据列表' },
            total: { type: 'integer', description: '总记录数' },
            page: { type: 'integer', description: '当前页码' },
            limit: { type: 'integer', description: '每页数量' },
            totalPages: { type: 'integer', description: '总页数' }
          }
        }
      }
    }
  },
  apis: ['./routes/*.js', './models/*.js'] // API路由文件路径
};

const swaggerSpec = swaggerJsdoc(swaggerOptions);
app.use('/api/docs', swaggerUi.serve, swaggerUi.setup(swaggerSpec));

// 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'
  })
})

// 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/suppliers', require('./routes/suppliers'))
app.use('/api/transport', require('./routes/transport'))
app.use('/api/finance', require('./routes/finance'))
app.use('/api/quality', require('./routes/quality'))

// 404 处理
app.use((req, res) => {
  res.status(404).json({
    success: false,
    message: '接口不存在',
    path: req.path
  })
})

// 错误处理中间件
app.use((err, req, res, next) => {
  console.error('Error:', err)
  
  res.status(err.status || 500).json({
    success: false,
    message: err.message || '服务器内部错误',
    timestamp: new Date().toISOString(),
    ...(process.env.NODE_ENV === 'development' && { stack: err.stack })
  })
})

const PORT = process.env.PORT || 3000

// 启动服务器
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}/api/docs`)
    })
  } catch (error) {
    console.error('❌ 服务器启动失败:', error)
    process.exit(1)
  }
}

startServer()