/* client4_select.c client skeleton for ex4 17 */
/* version to recv everything until user give more input or connection is closed */

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

/* official network end-of-line is CR LF */
#define EOL "\015\012"

/* size of the send/receive buffer */
#define MAXMSG 1000

/* this macro can be used to check errors, see server.c for examples */
#define ERRORCHEK(var, value, command)	if (var == value) {		\
											perror(command);	\
											exit(1); 			\
										}
int main(int argc, char *argv[])
{
    int ssock; /* socket to server */
	int numbytes, status;  
    char rbuf[MAXMSG]; /* receive buffer */
    char sbuf[MAXMSG*2]; /* send buffer */
    struct hostent *he;
    struct sockaddr_in se_addr; /* server address */
	int sin_size = sizeof(struct sockaddr_in); /* convenience constant */
	fd_set fds, orig_fds;
	int fdmax;
	int port = 9876;      /* default port */

    if (argc < 2) {
        fprintf(stderr,"usage: %s hostname [port]\n", argv[0]);
        exit(1);
    }

	/* get server address */
    he=gethostbyname(argv[1]);
    if (he == NULL) {
        perror("gethostbyname");
        exit(1);
    }

	/* port as optional second parameter */
	if (argc > 2)
		port = atoi(argv[3]);

	/* get socket */
    ssock = socket(AF_INET, SOCK_STREAM, 0);
    if (ssock == -1) {
        perror("socket");
        exit(1);
    }

	/* contruct address struct */
    se_addr.sin_family = AF_INET;    
    se_addr.sin_port = htons(port);  /* NBO */
    se_addr.sin_addr = *((struct in_addr *)he->h_addr);
    memset(&(se_addr.sin_zero), '\0', 8); 

	/* connect to the server */
    status = connect(ssock, (struct sockaddr *)&se_addr, sin_size);
	ERRORCHEK(status, -1, "connect");

	/* set up file descriptor set */
	FD_ZERO(&orig_fds);
	FD_SET(ssock, &orig_fds);
	FD_SET(STDIN_FILENO, &orig_fds); /* for keyboard */
	fdmax = ssock;

	/* main loop */
	do {
		/* wait until user of ssock has something to give */
		/* copy to temporary fds, select() changes the set */
		fds = orig_fds;

		status = select(fdmax+1, &fds, NULL, NULL, NULL);
		ERRORCHEK(status, -1, "select");

		/* user input */
		if (FD_ISSET(STDIN_FILENO, &fds)) {
			fgets(sbuf, MAXMSG-1, stdin);
			/* replace NL with CRNL */
			strcpy(sbuf+strlen(sbuf)-1, EOL);

			/* single send for short messages is ok */
			numbytes = send(ssock, sbuf, strlen(sbuf), 0);
			if (numbytes == -1) {
				perror("send");
				exit(1);
			} else if (numbytes != strlen(sbuf))
				printf("Only %d bytes sent! Should have used repeated send...\n", numbytes);

		} /* if stdin */

		/* incoming data */
		if (FD_ISSET(ssock, &fds)) {

			/* receive */
			numbytes=recv(ssock, rbuf, MAXMSG-1, 0);
			if (numbytes == -1) {
				perror("recv");
				exit(1);
			}

			if (numbytes == 0) {
				printf("Connectino closed\n");
				break;
			}

			/* terminate message to make a string */
			rbuf[numbytes] = '\0';

			printf("Received: %s",rbuf);
		} /* if ssock */

	} while (!strstr(sbuf, "quit"));

    close(ssock);

    exit(0);
}