package proxy

import (
	"net"
	"zproxy/zlog"
)

type UServerProxy struct {
	AnkiConn *UPacketConnection
}

func NewServerProxy() *UServerProxy {
	return &UServerProxy{}
}
func (server *UServerProxy) NewTcpConnection(client *UPacketConnection) {
	defer func() {
		if client == server.AnkiConn {
			return
		}
		err := client.Close()
		if err != nil {
			zlog.Error("close client error: ", err)
		}
	}()
	data := []byte("anki0000")
	_, err := client.Read(data, 4, 8)
	if err != nil {
		zlog.Error("read client error: ", client.Conn.RemoteAddr(), err.Error())
		return
	}
	zlog.Infof("new client %s %s", client.Conn.RemoteAddr(), data[4:])
	if string(data[4:]) == "anki" {
		server.AnkiConn = client
		return
	}
	if server.AnkiConn == nil {
		client.ForwardError(ErrNoAnkiProxy)
		return
	}
	_, err = server.AnkiConn.Write(data)
	if err != nil {
		return
	}
	client.Forward(server.AnkiConn)
	server.AnkiConn.Forward(client)
}
func (server *UServerProxy) ServeTCP(listenAddr string) error {
	// listenAddr 只能填端口号
	ln, err := net.Listen("tcp", listenAddr)
	if err != nil {
		zlog.Error("listen server error: ", err.Error(), listenAddr)
		return err
	}
	zlog.Infof("listen server %s", listenAddr)
	defer func(ln net.Listener) {
		err := ln.Close()
		if err != nil {
			zlog.Error("close listen server error: ", err.Error(), listenAddr)
		}
	}(ln)
	for {
		conn, err := ln.Accept()
		if err != nil {
			if IsTimeoutError(err) {
				continue
			}
			return err
		}
		go server.NewTcpConnection(NewPacketConnection(conn))
	}
}