// Package network 实现网络通信层
package network

import (
	"fmt"
	"io"
	"net"

	"git.pyer.club/kingecg/goaidb/protocol"
	"git.pyer.club/kingecg/goaidb/query"
	"git.pyer.club/kingecg/goaidb/storage"
)

// Server 网络服务器结构体
type Server struct {
	storage storage.StorageEngine
}

// NewServer 创建新的网络服务器
func NewServer(storage storage.StorageEngine) *Server {
	return &Server{storage: storage}
}

// Serve 启动服务
func (s *Server) Serve(listener net.Listener) {
	for {
		conn, err := listener.Accept()
		if err != nil {
			fmt.Printf("Failed to accept connection: %v\n", err)
			continue
		}
		go s.handleConnection(conn)
	}
}

// 处理客户端连接
func (s *Server) handleConnection(conn net.Conn) {
	defer conn.Close()
	buffer := make([]byte, 4*1024) // 4KB缓冲区

	for {
		n, err := conn.Read(buffer)
		if err != nil {
			if err != io.EOF {
				fmt.Printf("Error reading from connection: %v\n", err)
			}
			return
		}

		// 解析MongoDB协议消息
		message, err := protocol.ParseMessage(buffer[:n])
		if err != nil {
			fmt.Printf("Failed to parse message: %v\n", err)
			continue
		}

		// 处理查询请求
		response, err := query.HandleQuery(message, s.storage)
		if err != nil {
			fmt.Printf("Query handling error: %v\n", err)
			continue
		}

		// 发送响应
		_, err = conn.Write(response)
		if err != nil {
			fmt.Printf("Failed to send response: %v\n", err)
			return
		}
	}
}