#define MAX_MSG_LEN 1000
#define ERROR -1
#include <time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdlib.h>
#include <signal.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>

int newSd;
struct sockaddr_in cliAddr, servAddr;
int sd;
int isaclient=0; /*Set to 1 when a client connects*/
int send_message (char msg[MAX_MSG_LEN]);
void *get_messages (void *arg);
void processcmd(char cmd[MAX_MSG_LEN]);

/*======================================================================*/
/*======================================================================*/
int main (void)
{
  pthread_t mThreadId ;
  int status ;
 
  /*Creates a socket*/
  sd = socket(AF_INET, SOCK_STREAM, 0);
  if(sd<0) {
    perror("cannot open socket ");
    return ERROR;
  }
  /* bind server port */
  servAddr.sin_family = AF_INET;
  servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
  servAddr.sin_port = htons(9999);  
  if(bind(sd, (struct sockaddr *) &servAddr, sizeof(servAddr))<0) {
    perror("cannot bind port ");
    return ERROR;
  }
  listen(sd,5);


  /*Create a thread for the message handeling*/
  status = pthread_create(&mThreadId, NULL, get_messages, NULL) ;
  if (status != 0){
    printf("pthread_create failed, error %d", status) ;
  }


  /*Starts waiting for the termination of the thread*/
  status = pthread_join(mThreadId, NULL) ;
  if (status != 0) {
    printf("pthread_join failed, error %d", status) ;
  }

  return 0;
}
/*======================================================================*/
/*======================================================================*/
void *get_messages (void *arg) {  
  /* get_messages keeps reading the standard input. It identifies commands 
     and call procedure responding to these commands.
  */
  /*--------------------------------------------------------------------*/  
  int cliLen;
  int i;
  static int k,inaline=0;
  int nrec;
  static char rcv_msg[MAX_MSG_LEN];
  char cmd[MAX_MSG_LEN];
  char msg[MAX_MSG_LEN];
  
  /*Client waiting loop*/
  while (1) {
    cliLen = sizeof(cliAddr);
    newSd = accept(sd, (struct sockaddr *) &cliAddr, &cliLen);
    if(newSd<0) {
      perror("cannot accept connection ");
      return ERROR;
    }
    printf(" Connection opened by client\n");  
    isaclient=1;
  
    
    /*Message waiting loop*/
    while(1) {
      nrec = recv(newSd, rcv_msg, MAX_MSG_LEN, 0); /* wait for data */
      if (nrec<0) {
        perror(" cannot receive data ");
        return ERROR;
      } 
      else if (nrec==0) {
        printf(" Connection closed by client\n");
	
	isaclient=0;
	break;
      } 
      processcmd(rcv_msg);
    }
  }   
}
/*======================================================================*/
/*======================================================================*/
void processcmd(char cmd[MAX_MSG_LEN]) {  
  /* get_messages keeps reading the standard input. It identifies commands 
     and call procedure responding to these commands.
  */
  /*--------------------------------------------------------------------*/  
  printf("%s\n",cmd);
  printf("Response:");
  char msg[MAX_MSG_LEN];
  fgets(msg,MAX_MSG_LEN,stdin);
  send_message(msg);
  return;
}
/*======================================================================*/
/*======================================================================*/
int send_message (char msg[MAX_MSG_LEN]){
  /*--------------------------------------------------------------------*/  
  char msg2[MAX_MSG_LEN];
  if (isaclient) {
    msg[strlen(msg)-1]='\0';
    write(newSd,msg,strlen(msg));
  }
  return 0;
}
/*======================================================================*/