/*

NAME:       TCPClient 
SYNOPSIS:    TCPClient host_id port_number 
DESCRIPTION:    The program creates a stream socket in the inet domain, 
                Connects to TCPServer, 
                Gets messsages typed by a user and 
                Sends them to TCPServer running on hostid
                Then it waits for a reply from  the TCPServer
                and shows it back to the user, with a message
                indicating if there is an error during the round trip. 
*/
#include <sys/socket.h>  /* socket, connect, recv, send */
#include <arpa/inet.h>   /* htons  */
#include <netinet/in.h>  /* inet_addr */
#include <arpa/inet.h>   /* inet_addr */
#include <string.h>   /* memcpy  */
#include <stdio.h>   /*printf */
#include <unistd.h>   /* close */
#include <stdlib.h>  /* exit  */
#include <netdb.h>  /* gethostbyaddr  */

#define MAXHOSTNAME 80
#define BUFSIZE 1024
char buf[BUFSIZE];
char rbuf[BUFSIZE];
int cleanup(char * );

int main( int argc, char * argv[] ) {
    struct addrinfo hints, *result, *rp;
    struct addrinfo hints_local, *result_local;  
    int sfd, s, s2, rc, cc; 
    struct sockaddr_storage peer_addr;
    socklen_t peer_addr_len;
    ssize_t nread;
    char ThisHost[MAXHOSTNAME]; 

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

    gethostname(ThisHost, MAXHOSTNAME); 

    /*Obtain address(es) matching localhost/localport*/
    memset(&hints_local, 0, sizeof(hints_local));
    hints_local.ai_family = AF_INET; //IPv4
    hints_local.ai_socktype = SOCK_STREAM; //TCP
    hints_local.ai_flags = AI_PASSIVE;

    if (getaddrinfo(ThisHost, argv[2], &hints_local, &result_local) != 0)
    {
        fprintf(stderr, "getaddrinfo error\n");
        exit(EXIT_FAILURE);
    }



    printf("----EchoClient/TCP running at host NAME: %s\n", ThisHost);
    printf("(EchoClient/TCP INET ADDRESS is: %s )\n", inet_ntoa(((struct sockaddr_in*)result_local->ai_addr)->sin_addr));

    /*Obtain address(es) matching host/port*/
    memset(&hints, 0, sizeof(hints));
    hints.ai_family = AF_INET; //IPv4
    hints.ai_socktype = SOCK_STREAM; //TCP
    hints.ai_flags = AI_PASSIVE;

    if ((getaddrinfo(argv[1], argv[2], &hints, &result)) != 0)
    {
        fprintf(stderr, "Could not connect\n");
        exit(EXIT_FAILURE);
    }

    /* getaddrinfo() returns a list of address structures.
    Try each address until we successfully connect.
    If socket (or connect) fails, we (close the socket
    and) try the next address. */

    for ( rp = result; rp != NULL; rp = rp->ai_next)
    {
      s =  socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);

      if (s == -1)
      {
        continue;
      }
      
      if (connect(s, rp->ai_addr, rp->ai_addrlen) != 1)
      {
        break; //conexion satisfactoria
      }    

      close(s);  

    }

    freeaddrinfo(result);           /* No longer needed */

    if (rp == NULL) { // No hubo exito con ninguna direccion
           fprintf(stderr, "No se pudo realizar conexion\n");
           exit(EXIT_FAILURE);
    }

  printf("----EchoServer/TCP running at host NAME: %s\n", argv[1]);


  printf("(EchoServer/TCP INET ADDRESS is: %s )\n", inet_ntoa(((struct sockaddr_in*)rp->ai_addr)->sin_addr));

  /*     get data from USER, send it SERVER,
      receive it from SERVER, display it back to USER  */

  for(;;) {
    printf("\nType anything followed by RETURN, or type CTRL-D to exit\n");
    cleanup(buf);
    cleanup(rbuf);
    rc=read(0,buf, sizeof(buf));
    if (rc == 0) break;
    if (send(s, buf, rc, 0) <0 )
      perror("sending stream message");
    if ((cc=recv(s, rbuf, sizeof(rbuf), 0)) < 0)
      perror("receiving echo");
    if (cc == rc)
      if (strcmp(buf, rbuf) == 0){
        printf("Echo is good\n");
        printf("  Received: %s", rbuf);
      }
      else
        printf("Echo bad -- strings unequal: %s\n", rbuf);
    else
      printf("Echo bad -- lengths unequal: %s\n", rbuf);
  }
  printf ("EOF... exit\n");
  close(s);
  exit (0);
}
int cleanup(char * buf)  {
  int i;
  for(i=0; i<BUFSIZE; i++) buf[i]='\0';
}