#include "main.h"

//======================================================================
//						MAIN
//======================================================================
int main(int argc, char **argv)
{
	int portNumber;
	struct sockaddr_in myAddr;
	int ok;
	int clients[0x100];
	int nbClients=0;
	
	int i;
	struct sockaddr_in fromAddr;
	char buffer[0x100];
	
	//---- check command line arguments ----
	if(argc!=2)
				{ fprintf(stderr,"usage: %s port\n",argv[0]); exit(1); }

	//---- extract local port number ----
	if(sscanf(argv[1],"%d",&portNumber)!=1)
				{ fprintf(stderr,"invalid port %s\n",argv[1]); exit(1); }

	//---- create listen socket ----
	int listenSocket=socket(PF_INET,SOCK_STREAM,0);
	if(listenSocket==-1)
				{ perror("socket"); exit(1); }
				
	// ... avoiding timewait problems (optional)
	int on=1;
	ok = setsockopt(listenSocket,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(int));
								if( ok == -1 ){ perror("setsockopt"); exit(1); }
	  
	// ... bound to any local address on the specified port
	myAddr.sin_family=AF_INET;
	myAddr.sin_port=htons(portNumber);
	myAddr.sin_addr.s_addr=htonl(INADDR_ANY);
	ok = bind(listenSocket,(struct sockaddr *)&myAddr,sizeof(myAddr));
								if( ok == -1 ){ perror("bind"); exit(1); }
	// ... listening connections
	ok = listen(listenSocket,10);
								if( ok == -1 ){ perror("listen"); exit(1); }


	for(;;)
	  {
				  //---- wait for new connections or incoming messages ----
				  fd_set rdSet;
				  FD_ZERO(&rdSet);
				  FD_SET(listenSocket,&rdSet);
				  int maxFd=listenSocket;
		
				  for(i=0;i<nbClients;++i)
					{
						FD_SET(clients[i],&rdSet);
						if(clients[i]>maxFd) maxFd=clients[i];
					}
				  ok = select(maxFd+1,&rdSet,(fd_set *)0,(fd_set *)0,(struct timeval *)0);
								if( ok == -1 ){ perror("select"); exit(1); }

				  //---- accept and store new connection (if available) ----
				  if(FD_ISSET(listenSocket,&rdSet))
					{

						socklen_t len=sizeof(fromAddr);
						int dialogSocket=accept(listenSocket,(struct sockaddr *)&fromAddr,&len);
						if(dialogSocket==-1)
									{ perror("accept"); exit(1); }
						printf("new connection from %s:%d\n",inet_ntoa(fromAddr.sin_addr),ntohs(fromAddr.sin_port));
						clients[nbClients++]=dialogSocket;
					}

				  //---- dialog with each client providing a message ----
				  for(i=nbClients;i--;)
					{
							int dialogSocket=clients[i];
							if(FD_ISSET(dialogSocket,&rdSet))
							  {
								  //---- receive and display message from client (if available) ----
								  int nb=recv(dialogSocket,buffer,0x100,0);
								  if(nb<=0)
									{
										printf("client disconnected\n");
										close(dialogSocket);
										clients[i]=clients[--nbClients];
									}
								  else
									{
										buffer[nb]='\0';
										printf("%s\n",buffer);
										//---- send reply to client ----
										nb=sprintf(buffer,"%d bytes received\n",nb);
										ok = send(dialogSocket,buffer,nb,0);
														if( ok == -1 ){ perror("send"); exit(1); }
									}
							  }
					}
	  }
	close(listenSocket);
	return 0;
	}

//----------------------------------------------------------------------------