/* ========================================================================== */
/*                                                                            */
/*   server.c                                                                 */
/*   (c) 2008 jocelyne.lecomte@alcatel-lucent.fr                              */
/*                                                                            */
/*   Description                                                              */
/*                                                                            */
/* ========================================================================== */
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

#include "server.h"

/*******************************************************************************/
/*  Initialize connection  */
/*******************************************************************************/
static int init_connection(void)
{
  /* UDP protocol, so SOCK_DGRAM */
  SOCKET sock = socket(AF_INET, SOCK_DGRAM, 0);
  fprintf(stdout, "create socket\n");
  
  /* ERROR */
  if (sock == INVALID_SOCKET)
  {
    perror("socket()");
    exit(errno);
  }
  
  /* OK */
  SOCKADDR_IN sin ={0};
  
  sin.sin_addr.s_addr = htonl(INADDR_ANY);
  sin.sin_port = htons(PORT);
  sin.sin_family = AF_INET;
  
  if (bind(sock, (SOCKADDR *) &sin, sizeof sin) == SOCKET_ERROR)
  { 
    perror("bind()");
    exit(errno);
  }
  fprintf(stdout, "socket OK\n");
  return sock;
}

/*******************************************************************************/
/*  close socket */
/*******************************************************************************/
static void end_connection(SOCKET sock)
{
  close(sock);
  fprintf(stdout, "close socket\n");

}


/*******************************************************************************/
/* read data from client */
/*******************************************************************************/
static int read_client(SOCKET sock, SOCKADDR_IN *sin, char *buffer)
{
  int n=0;
  size_t sinsize = sizeof *sin;
  /* error in reception */
  if ((n = recvfrom(sock, buffer, BUF_SIZE-1, 0, (SOCKADDR*)sin, &sinsize))<0)
  {
    perror("recvfrom()");
    exit(errno);
  }
  /* OK */
  fprintf(stdout, "read socket from client\n");
  buffer[n] = 0;
  return n;
}

/*******************************************************************************/
/* write data to client */
/*******************************************************************************/
static void write_client(SOCKET sock, SOCKADDR_IN *sin, const char* buffer)
{
   /* error in sending msg */
  if (sendto(sock, buffer, strlen(buffer), 0, (SOCKADDR*)sin, sizeof *sin)<0)
  {
    perror("sendto()");
    exit(errno);
  }
  fprintf(stdout, "write socket to client\n");

}

/*******************************************************************************/
/* etablish communication */
/*******************************************************************************/
void comm(void)
{
  SOCKET sock = init_connection();
  
  char buffer[BUF_SIZE];

  /* index of array */
  int actual = 0;
  int max = sock;
  
  /* array for clients */
  Client clients[MAX_CLIENTS];
  fd_set readfs;

  while(1)
  {
    /* set the descripor to null */
    FD_ZERO(&readfs);

    /* add STDIN_FILENO */
    FD_SET(STDIN_FILENO, &readfs);
    
    /* add the socket */
    FD_SET(sock, &readfs);
    
    /* management of modication of descriptors */
    struct timeval timeout;
    timeout.tv_sec = 20;
    timeout.tv_usec = 0;
    
    fprintf(stdout, "before select()\n");
    if (select(max+1, &readfs, NULL, NULL, &timeout)==-1)
/*
    fprintf(stdout, "before select()\n");
    if (select(max+1, &readfs, NULL, NULL, NULL)==-1)
*/    
    {
      perror("select()");
      exit(errno);
    }
    
    fprintf(stdout, "after select()\n");
    
    /* something from standard input */
    if (FD_ISSET(STDIN_FILENO, &readfs))
    {
      /* stop process when type on keyboard */
      break;
    }
    
    else if (FD_ISSET(sock, &readfs))
    {
      /* new client */
      SOCKADDR_IN csin = {0};
      
      fprintf(stdout, "new client");
      
      /* a client is talking */
      read_client(sock, &csin, buffer);
      fprintf(stdout, buffer);
      
      /* write back to client */
      write_client(sock, &csin, buffer);
      
      /* TODO */
    }
  }
  end_connection(sock);
}

static void send_msg_to_all_clients(SOCKET sock, Client *clients, Client *client, int actual, const char *buffer, char from_server)
{
  fprintf(stderr, "Not yet implemented\n");
}

static void remove_client(Client *clients, int to_remove, int *actual)
{
  fprintf(stderr, "Not yet implemented\n");
}
static check_if_client_exist(Client *clients, SOCKADDR_IN *csin, int actual)
{
  fprintf(stderr, "Not yet implemented\n");
  return 0;
}
static Client* get_client(Client *clients, SOCKADDR_IN *csin, int actual)
{
  fprintf(stderr, "Not yet implemented\n");
  return NULL;
}