#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "restart.h"
#include "uici.h"
#include "nqueens_library.c"

static pthread_mutex_t lock;
int main(int argc, char *argv[]) {
   int bytescopied;
   char client[MAX_CANON];
   int communfd;
   int listenfd;
   u_port_t portnumber;
   pid_t child;
   thread_info_t info;
   int solution, totalSolutions;

   if (argc != 2) {
      fprintf(stderr, "Usage: %s port\n", argv[0]);
      return 1;
   }

   //mutex init
   if (pthread_mutex_init(&lock, NULL) != 0)
   {
       printf("\n mutex init failed\n");
       return 1;
    }

    portnumber = (u_port_t) atoi(argv[1]);
    if ((listenfd = u_open(portnumber)) == -1) {
       perror("Failed to create listening endpoint");
       return 1;
    }

    fprintf(stderr, "[%ld]: Waiting for connection on port %d\n",
     (long)getpid(), (int)portnumber);

    for ( ; ;  ) {
      if ((communfd = u_accept(listenfd, client, MAX_CANON)) == -1) {
       perror("Failed to accept connection");
       continue;
      }

     fprintf(stderr, "[%ld]:connected to %s\n", (long)getpid(), client);

     // fork a process
     if ((child = fork()) == -1)
        perror("Failed to fork a child");

     if (child == 0) {  /* child code */
        if (r_close(listenfd) == -1) {
           fprintf(stderr, "[%ld]:failed to close listenfd: %s\n", (long)getpid(), strerror(errno));
           return 1;
        }

        bytescopied = r_read(communfd, &info, sizeof(thread_info_t));
        solution = generate_n_queens_server_one(info.n, info.first, communfd);

        //pthread_mutex_lock(&lock);
        info.result = solution;
        pthread_mutex_lock(&lock);
        //fprintf(stderr, "\nn = %d, first = %d\n", info.n, info.first);
        fprintf(stderr, "\nSolutions: %d\n", solution);
        fprintf(stderr, "[%ld]:received %d bytes\n", (long)getpid(), bytescopied);
        //r_write(communfd, &solution, sizeof(int));
        pthread_mutex_unlock(&lock);

        //added this

        return 0;
     }
   if (r_close(communfd) == -1)                             /* parent code */
      fprintf(stderr, "[%ld]:failed to close communfd: %s\n", (long)getpid(), strerror(errno));
 //  while (r_waitpid(-1, NULL, WNOHANG) > 0);  /* clean up zombies */

   }
}