#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <ctype.h>


#define SERVERPORT 14675
#define MAXLINE 128

int main(int argc, char *argv[])
{
	int sockfd;
	struct sockaddr_in their_addr;
	struct hostent *he;
	int i,j,sendline_count,numbytes;
	int broadcast = 1;
	unsigned char sendline[MAXLINE];

	if (argc != 5) {
		printf("usage: Model_Name Device_Name Workgroup Firmware_version\n");
		exit(1);
	}

	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		perror("socket");
		exit(1);
	}

	// this call is the difference between this program and talker.c:
	if (setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &broadcast,
		sizeof broadcast) == -1) {
		perror("setsockopt (SO_BROADCAST)");
		exit(1);
	}

	their_addr.sin_family = AF_INET;	 // for IPv4
	their_addr.sin_port = htons(SERVERPORT); // Host to Network Short
	//their_addr.sin_addr.s_addr = INADDR_BROADCAST; //INADDR_BROADCAST address (255.255.255.255) 若有雙網卡, 則須看 route 指定的 0.0.0.0 的 interface
	//their_addr.sin_addr.s_addr = inet_addr("192.168.100.24"); // 到 192.168.100.24
	their_addr.sin_addr.s_addr = inet_addr("192.168.100.255"); // 到 192.168.100.x
	memset(their_addr.sin_zero, '\0', sizeof their_addr.sin_zero);
	memset(sendline, 0x0, 71);

	//分別將 Modelname, DeviceName, GroupName, Version 填入sendline中
	sendline_count = 0; 
	for(j=1; j<5; j++)
	{
		char tmp[30];
		strcpy(tmp,argv[j]);
		for(i=0; i<strlen(tmp); i++)
		{
			sendline[i+sendline_count] = tmp[i];
		}
		//分隔字元
		sendline[sendline_count+strlen(tmp)] = 0x2;

		//設定目前 sendline 長度
		sendline_count += strlen(tmp);
		sendline_count++;

		//printf("%s,%i --> %s\n",tmp,sendline_count,sendline);
	}

	if ((numbytes=sendto(sockfd, sendline, strlen(sendline), 0,
			 (struct sockaddr *)&their_addr, sizeof their_addr)) == -1) {
		perror("sendto");
		exit(1);
	}

  shutdown(sockfd, SHUT_RDWR);
	close(sockfd);

	return 0;
}