#include <winsock2.h>
#include <io.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#define BUFSIZE			8192
#define DEFAULT_PORT	5320

enum {CMD_NAME,DST_IP,DST_PORT};
void InitWinSocket();
void ParseCmdLine(int*port ,unsigned long *ip,int argc,char*argv[]);
void CreateTcpSocket(SOCKET* sock);
void ConnectToServer(SOCKET sock,unsigned long dst_ip,int port);
void CommunicateWithServer(SOCKET sock);
void ReceiveFromServer(SOCKET sock);
int	ReadFromKeyBoardAndSandToServer(SOCKET sock);
int main(int argc, char *argv[]){
	SOCKET sock;
	unsigned long dst_ip;
	int port;

	InitWinSocket();
	ParseCmdLine(&port,&dst_ip,argc,argv);
	CreateTcpSocket(&sock);

	ConnectToServer(sock,dst_ip,port);
	CommunicateWithServer(sock);

	closesocket(sock);
	WSACleanup(); 

	return 0;
}
void CommunicateWithServer(SOCKET sock){
//	int n;
//	char cmd[BUFSIZE];
	char buf[BUFSIZE];
	struct timeval tv;

	fd_set readfd;
	tv.tv_sec=600;
	tv.tv_usec=0;
	while(true){
		FD_ZERO(&readfd);
		FD_SET(0,&readfd);
		FD_SET(sock,&readfd);
		select(sock+1,&readfd,NULL,NULL,&tv);
		
		if(FD_ISSET(0,&readfd)){
			if(ReadFromKeyBoardAndSandToServer(sock)<0)
				break;
		}
		if(FD_ISSET(sock,&readfd))
			ReceiveFromServer(sock);
	}
	strcpy(buf,"quit");
	send(sock,buf,strlen(buf),0);
}	
void ReceiveFromServer(SOCKET sock){
	int n;
	char buf[BUFSIZE];
	if((n=recv(sock,buf,BUFSIZE-1,0))<=0){
		perror("timeout recv");
		exit(-1);
	}
	buf[n]='\0';
	printf("%s",buf);
	fflush(stdout);
	
}
int	ReadFromKeyBoardAndSandToServer(SOCKET sock){
	int n,flag=0;
	char cmd[BUFSIZE];
	char buf[BUFSIZE];
	if((n=_read(0,buf,BUFSIZE-1))>0){
		buf[n]='\0';
		sscanf(buf,"%s",cmd);
		if(strcmp(cmd,"quit")==0)	flag=-1;
		if(send(sock,buf,n,0)<0)	flag=-1;
	}
	return flag;
}
	
void InitWinSocket(){
	WSADATA wsaData;

	if (WSAStartup(MAKEWORD(2,1),&wsaData) != 0){
	fprintf(stderr,"WSAStartup failed: %d\n",GetLastError());
	exit(EXIT_FAILURE);
  }
}

void ParseCmdLine(int*port ,unsigned long *ip,int argc,char*argv[]){
	if(argc != 2 && argc!=3){
		fprintf(stderr," Usag: %s hostname [port]\n",argv[0]);
		exit(EXIT_FAILURE);
	}

	if((*ip=inet_addr(argv[DST_IP]))==INADDR_NONE){
		struct hostent* he;
		if((he=gethostbyname(argv[DST_IP]))==NULL){
			fprintf(stderr,"gethostbyname error\n");
			exit(EXIT_FAILURE);

		}
		memcpy((char*)ip,(char*)he->h_addr,he->h_length);
	}
	*ip=ntohl(*ip);
	if(argc==3){
		if((*port=(atoi(argv[DST_PORT])))==0){
			struct servent *se;
			if((se=getservbyname(argv[DST_PORT],"TCP"))!=NULL)
				*port=(int)ntohs((u_short)se->s_port);
			else{
				fprintf(stderr,"getservbynmame error\n");
				exit(EXIT_FAILURE);
			}
		}
	}else *port=DEFAULT_PORT;

}	

void CreateTcpSocket(SOCKET* sock){
	if((*sock=socket(AF_INET,SOCK_STREAM,0))<0){
		perror("socket");
		exit(EXIT_FAILURE);
	}
}

void ConnectToServer(SOCKET sock,unsigned long dst_ip,int port){
	struct sockaddr_in server;
	memset((char*)&server,0,sizeof(server));
	server.sin_family=AF_INET;
	server.sin_addr.s_addr=htonl(dst_ip);
	server.sin_port=htons(port);

	if(connect(sock,(struct sockaddr*)&server,sizeof(server))<0){
		perror("connect");
		exit(EXIT_FAILURE);
	}
}