#include <stdio.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
 #include <netinet/in.h>

// 子執行緒負責寫資料
void *write_data(void *v)
{
	int conm_socket = *(int*)v;
	
	char buf[1024];
	while (1)
	{
		struct sockaddr_in client_addr;
		socklen_t  len = sizeof(client_addr);
		ssize_t ret = recvfrom(conm_socket, buf, 1023, 0, (struct sockaddr *)&client_addr, &len);// 收
		if (-1 == ret)
		{
			perror ("read error");
		}
		if (0 == ret)
		{
			printf ("客戶端退出\n");
			break;
		}
		buf[ret] = '\0';
		printf ("%s\n", buf);
	}	
}

// 主執行緒負責讀資料
void read_data(int conm_socket, char **argv)
{

	// 接收方的地址
	struct sockaddr_in addr;
	memset(&addr, 0, sizeof(struct sockaddr_in));
	addr.sin_family      = AF_INET;                      /* Internet地址族 */
	addr.sin_port        = htons(atoi(argv[2]));         /*伺服器用的埠號 */
	addr.sin_addr.s_addr = inet_addr(argv[1]);           /*伺服器用的IP地址 */
	
	char buf[1024];
	while (1)
	{
		fgets(buf, 1024, stdin);
		sendto(conm_socket, buf, strlen(buf), 0, (struct sockaddr *)&addr,  sizeof(addr));
	}	
	
}

int main(int argc, char **argv)
{
	// 1、建立套接字
	int conn_socket = socket(AF_INET, SOCK_DGRAM, 0);
	if(-1 == conn_socket)
	{
		perror("建立套接字失敗");
		return -1;
	}
	
	pthread_t thread;
	pthread_create(&thread, NULL, write_data, (void *)&conn_socket);
	
	read_data(conn_socket, argv);
	
	close(conn_socket);
	
	return 0;
}