#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 "tools.h"

#define SERVERPORT 3081	// the port users will be connecting to
#define PORT_MY_ID_LAST_3_DIG 294
#define PORT_PEER_UDP_BASE 4100
#define PORT_OFFSET_PER_PEER 100
#define MY_UDP_PORT(provider_Num) (PORT_PEER_UDP_BASE+PORT_OFFSET_PER_PEER*provider_Num+PORT_MY_ID_LAST_3_DIG)
#define BUF_SIZE 100
#define TEMP_BUF_SIZE 100
#define MAXBUFLEN 100
#define MAXDATASIZE 100

struct SGROUP_DATA
{
	int txt_LineNumber;// line number stored in directory.txt
	char name[4][5]; // group member name
	unsigned int portnum[4]; // port number
	int groupNum[4]; // which group belong to
	char IPaddress[4][16]; // the ip address of each group
	int g_memberSize[2];//how many members in this group
	int groupMember[2][4];// the order of each group
	struct sockaddr_in my_TCP_peer_addr[4];
};
typedef struct SGROUP_DATA SGROUP_DATA;

SGROUP_DATA group_data;
char* ProviderName[2] = {"provider1","provider2"};
int providerID=0;
char OutBuf1[TEMP_BUF_SIZE];
char OutBuf2[TEMP_BUF_SIZE];
char InBuf1[TEMP_BUF_SIZE];
char InBuf2[TEMP_BUF_SIZE];
/*************************************************************
void init(void)
Func: initialization
**************************************************************/
void init(void)
{
	int i,j;
	group_data.txt_LineNumber = 0;
	group_data.g_memberSize[0]=0;
	group_data.g_memberSize[1]=0;
	for(i = 0; i<2;i++)
		for(j=0;j<4;j++){
			group_data.groupMember[i][j]=9;
		}
}
/*************************************************************
void assign2DataStructure(int peerNum,struct hostent * p)
**************************************************************/
void assign2DataStructure(int peerNum,struct hostent * p)
{
	unsigned short int pnum = group_data.portnum[peerNum];
	group_data.my_TCP_peer_addr[peerNum].sin_family = AF_INET;
	group_data.my_TCP_peer_addr[peerNum].sin_port = htons(pnum);
	group_data.my_TCP_peer_addr[peerNum].sin_addr = *((struct in_addr *)p->h_addr);
	memset(&(group_data.my_TCP_peer_addr[peerNum].sin_zero), '\0', 8); 
	
}
/************************************************************
void rcv_ack(int fd)
function: receiving a ack
*************************************************************/
void rcv_ack(int fd)
{	
	int numbytes;
	if ((numbytes=recv(fd, InBuf1, 19, 0)) == -1) {
	        perror("ack");
	        exit(1);
	}
}
/************************************************************
void strcatName(void)
function:append the sender's name to the string
*************************************************************/
void strcatName(void)
{
	memset(OutBuf1, '\0',TEMP_BUF_SIZE); 
	strcat(OutBuf1,ProviderName[providerID]);
}
/************************************************************
void strcatGroupSize(int size)
function: append the group size to the string
para: size, group size
*************************************************************/
void strcatGroupSize(int size)
{
	strcat(OutBuf1," ");
	memset(OutBuf2, '\0',TEMP_BUF_SIZE); 
	itostr(OutBuf2, size) ;
	OutBuf2[1]='\0';
	strcat(OutBuf1, OutBuf2);
}
/************************************************************
void strcatGroupNumber(void)
function: append the group number to the string
*************************************************************/
void strcatGroupNumber(void)
{
	memset(OutBuf2, '\0',TEMP_BUF_SIZE); 
	itostr(OutBuf2, providerID+1) ;
	OutBuf2[1]='\0';
	strcat(OutBuf1, OutBuf2);
}
/************************************************************
void sendDataToPeer(int Gnum,int size)
function : send the group information to the next peer
parameter:
Gnum: group number
size: group size
*************************************************************/
void sendDataToPeer(int Gnum,int size)
{
	int sockfd, numbytes;  
	int i,j;
	int stop = 0;
	struct hostent *he;
	struct sockaddr_in their_addr;
	/*****************************************
	*                    Open a new TCP socket
	*****************************************/
	if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
		perror("socket");
		exit(1);
	}
	if (connect(sockfd, (struct sockaddr *)&group_data.my_TCP_peer_addr[group_data.groupMember[Gnum][0]],
	                                          sizeof(struct sockaddr)) == -1) {
		perror("connect");
		exit(1);
	}
	
       /*****************************************
       * 			send message 1
       ******************************************/
	/* provider name*/
	strcatName();
	/* group size remained*/
	strcatGroupSize(size);
	if (send(sockfd, OutBuf1, strlen(OutBuf1), 0) == -1)
		perror("send");
 	rcv_ack(sockfd);

	/*****************************************
       * 			send message 2
       ******************************************/
	/* provider name*/
	strcatName();
	/*welcome message */
	strcat(OutBuf1," welcome to group");
	/* group number*/
	strcatGroupNumber();
	if (send(sockfd, OutBuf1, strlen(OutBuf1), 0) == -1)
		perror("send");
	rcv_ack(sockfd);

	/*****************************************
	*			send rest message
	******************************************/
	for(i=0; i<4;i++){ 
		if(group_data.groupNum[i]== Gnum+1){
			if(stop == 0){
				stop = 1;//skip the first one
				continue;
			}
			strcatName();
			
			/*strcat peer name*/
			strcat(OutBuf1," ");
			memcpy(OutBuf2, &group_data.name[i][0],5);
			OutBuf2[5]='\0';
			strcat(OutBuf1, OutBuf2);
		
			/*strcat peer port num*/
			strcat(OutBuf1," ");
			memset(OutBuf2, '\0',TEMP_BUF_SIZE); 
			itostr(OutBuf2, group_data.portnum[i]);
			OutBuf2[5]='\0';
			strcat(OutBuf1, OutBuf2);
			if (send(sockfd, OutBuf1, strlen(OutBuf1), 0) == -1)
                		perror("send");
	          	rcv_ack(sockfd);
	          	
          	}
          }
          close(sockfd);
} 

int main(int argc, char *argv[])
{
	int UDP_sockfd;
	int TCP_sockfd;
	struct sockaddr_in my_UDP_addr; // connect to  server
	struct sockaddr_in my_TCP_addr;// 
	struct sockaddr_in their_addr; //bootstrap
	struct sockaddr_in their_addr2; //bootstrap
	struct hostent *he;
	int numbytes;
	int i,j;
	socklen_t addr_len;
	FILE *fp;
	char peerName[5];
	
	addr_len = sizeof(struct sockaddr);
	init();
	
	/* get the host info */
	if ((he=gethostbyname("localhost")) == NULL) {  
		perror("gethostbyname");
		exit(1);
	}
	/* fork 2 providers*/
		
	if( fork() == 0 )
		providerID++;
	
	/* open the UDP*/
	if ((UDP_sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		perror("UDPsocket");
		exit(1);
	}
	/* create a UDP socket and bind a dedicated port*/
	
	my_UDP_addr.sin_family = AF_INET;		 // host byte order
	my_UDP_addr.sin_port = htons(MY_UDP_PORT(providerID));	 // short, network byte order
	my_UDP_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP
	memset(&(my_UDP_addr.sin_zero), '\0', 8); // zero the rest of the struct
	
	if (bind(UDP_sockfd, (struct sockaddr *)&my_UDP_addr,
		sizeof(struct sockaddr)) == -1) {
		perror("bind");
		exit(1);
	}
	/* Try to send the registration data*/

	/*provider name*/
	strcatName();
	
	/*user name and pwd*/
	strcat(OutBuf1," provider spring07");

	their_addr.sin_family = AF_INET;	 // host byte order
	their_addr.sin_port = htons(SERVERPORT); // short, network byte order
	their_addr.sin_addr = *((struct in_addr *)he->h_addr);
	memset(&(their_addr.sin_zero), '\0', 8);  // zero the rest of the struct
	/*send the registration data*/
	if ((numbytes = sendto(UDP_sockfd, OutBuf1, strlen(OutBuf1), 0,
			 (struct sockaddr *)&their_addr, sizeof(struct sockaddr))) == -1) {
		perror("sendto");
		exit(1);
	}
	/*try to receive file name*/
	if ((numbytes = recvfrom(UDP_sockfd, InBuf1, MAXBUFLEN-1 , 0,
			(struct sockaddr *)&their_addr2, &addr_len)) == -1) {
			perror("recvfrom");
			exit(1);
	}
	InBuf1[numbytes] = '\0';
	getStrSegment(InBuf1,InBuf2,2);// the file name is stored at 2nd segment
	
	/*Open the file*/
	fp = fopen(InBuf2, "r"); 
	if(!fp) printf("open error");
	 fseek(fp,0,SEEK_SET);
	 
	/*store all the data scaned from file*/
	 while(!feof(fp)){
 	 	fscanf(fp,"%s %u %s %d\n",&group_data.name[group_data.txt_LineNumber][0],
 	 						&group_data.portnum[group_data.txt_LineNumber],
 	 						&group_data.IPaddress[group_data.txt_LineNumber][0],
 	 						&group_data.groupNum[group_data.txt_LineNumber]);
 	 	if(group_data.groupNum[group_data.txt_LineNumber]== 1){
			group_data.groupMember[0][group_data.g_memberSize[0]]=group_data.txt_LineNumber;
 	 		group_data.g_memberSize[0]++;

 	 	}
 	 	if(group_data.groupNum[group_data.txt_LineNumber]== 2){
			group_data.groupMember[1][group_data.g_memberSize[1]]=group_data.txt_LineNumber;
 	 		group_data.g_memberSize[1]++;
 	 	}
 	 
 	 	assign2DataStructure(group_data.txt_LineNumber,he);
 	 	group_data.txt_LineNumber++;
 	 
	 }

	printf("Group %d has %d peer subscribers\n",providerID+1,group_data.g_memberSize[providerID]);
	/*if group size >0, send the rest data*/
	if(group_data.g_memberSize[providerID]>0)
		sendDataToPeer(providerID,group_data.g_memberSize[providerID]);

	
	
	memcpy(OutBuf1,group_data.name[group_data.groupMember[providerID][0]],5);
	OutBuf1[5] = '\0';
	if(group_data.g_memberSize[providerID]!=0)
		printf("%s joined group %d\n",OutBuf1,providerID+1);
	/*send to bootstrap server, to notify it the content provider is done. */
	 if ((numbytes = sendto(UDP_sockfd, "ack", 4, 0,
			 (struct sockaddr *)&their_addr, sizeof(struct sockaddr))) == -1) {
		perror("sendto");
		exit(1);
	}
	close(UDP_sockfd);
	return 0;
}