#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>

#define  INVALID_SOCKET  (-1)
#define  SOCKET_ERROR    (-1)
#define  MAX_LENGTH      60000

bool stop = false;

void * sendThread ( void * args )
{
	int clientSocket;
	ssize_t bytesSent = SOCKET_ERROR;
	char sendBuf[MAX_LENGTH] = "";

	clientSocket = *(int *)args;

	while ( stop == false )
	{
		if ( fgets( sendBuf, sizeof(sendBuf), stdin ) == NULL )
		{
			stop = true;
			shutdown( clientSocket, SHUT_RDWR );
			close( clientSocket );
			return NULL;
		}
		bytesSent = send( clientSocket, sendBuf, strlen(sendBuf), 0);
		if ( bytesSent == SOCKET_ERROR )
			fprintf ( stderr, "Error Sending Message.\n" );
	}
	shutdown( clientSocket, SHUT_RDWR );
	close( clientSocket );
	return NULL;
}

void * recvThread ( void * args )
{
	int clientSocket;
	ssize_t bytesRecv = 0;
	char recvBuf[MAX_LENGTH] = "";

	clientSocket = *(int *)args;

	while ( bytesRecv != SOCKET_ERROR && stop == false )
	{
		bytesRecv = recv (clientSocket, recvBuf, sizeof(recvBuf), 0);
		if ( bytesRecv == 0 )
		{
			printf ( "Connection Closed.\n" );
			stop = true;
			shutdown( clientSocket, SHUT_RDWR );
			close( clientSocket );
			return NULL;
		}
		if ( bytesRecv < 0 )
		{
			stop = true;
			shutdown( clientSocket, SHUT_RDWR );
			close( clientSocket );
			return NULL;
		}
		recvBuf[bytesRecv] = '\0';
		puts ( recvBuf );
	}
	shutdown( clientSocket, SHUT_RDWR );
	close( clientSocket );
	return NULL;
}

int main ( void )
{
	int serverSocket, clientSocket = SOCKET_ERROR;
	struct sockaddr_in serverService, clientService;
	socklen_t addrlen;

	pthread_t pSendThread, pRecvThread;

	serverSocket = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP );
	if ( serverSocket == INVALID_SOCKET )
	{
		fprintf ( stderr, "Socket Initialization Error.\n" );
		return EXIT_FAILURE;
	}

	memset( &serverService, 0, sizeof(serverService) );
	serverService.sin_family = AF_INET;
	serverService.sin_addr.s_addr = INADDR_ANY;
	serverService.sin_port = htons(2007);
	if ( bind( serverSocket, (struct sockaddr *)&serverService, sizeof(serverService) ) == SOCKET_ERROR )
	{
		fprintf ( stderr, "Bind failed.\n" );
		shutdown( serverSocket, SHUT_RDWR );
		close( serverSocket );
		return EXIT_FAILURE;
	}
	if ( listen( serverSocket, 1 ) == SOCKET_ERROR )
	{
		fprintf ( stderr, "Listen failed.\n" );
		shutdown( serverSocket, SHUT_RDWR );
		close( serverSocket );
		return EXIT_FAILURE;
	}
	printf ( "Waiting for a client to connect...\n" );
	clientSocket = SOCKET_ERROR;
	addrlen = sizeof(clientService);
	while ( clientSocket == SOCKET_ERROR )
	{
		clientSocket = accept ( serverSocket, (struct sockaddr *)&clientService, &addrlen );
	}
	printf ( "%s:%d connected.\n", inet_ntoa(clientService.sin_addr), ntohs(clientService.sin_port) );

	if ( pthread_create( &pSendThread, NULL, sendThread, &clientSocket ) )
	{
		fprintf ( stderr, "Message sending thread Creation Failed.\n" );
	}
	if ( pthread_create( &pRecvThread, NULL, recvThread, &clientSocket ) )
	{
		fprintf ( stderr, "Message receiving thread Creation Failed.\n" );
	}

	pthread_join( pSendThread, NULL );
	pthread_join( pRecvThread, NULL );

	shutdown( clientSocket, SHUT_RDWR );
	close( clientSocket );
	shutdown( serverSocket, SHUT_RDWR );
	close( serverSocket );
	return EXIT_SUCCESS;
}