/*
    CrossFire, A Multiplayer game for X-windows

    Copyright (C) 2001 Mark Wedel
    Copyright (C) 1992 Frank Tore Johansen

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    The author can be reached via e-mail to <crossfire@schmorp.de>
*/

/**
 * \file
 * Socket general functions
 *
 * \date 2003-12-02
 *
 * Mainly deals with initialization and higher level socket
 * maintenance (checking for lost connections and if data has arrived.)
 * The reading of data is handled in ericserver.c
 */


#include <global.h>
#include <sproto.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif

#ifdef HAVE_ARPA_INET_H
# include <arpa/inet.h>
#endif
#include <newserver.h>

Socket_Info socket_info;
NewSocket *init_sockets;

/**
 * Initializes a connection. Really, it just sets up the data structure,
 * socket setup is handled elsewhere.  We do send a version to the
 * client.
 */
void
InitConnection (NewSocket *ns, const char *from_ip)
{
  int bufsize = 65535;          /*Supposed absolute upper limit */
  int oldbufsize;
  int buflen = sizeof (int);

  if (fcntl (ns->fd, F_SETFL, O_NONBLOCK) == -1)
    LOG (llevError, "InitConnection:  Error on fcntl.\n");

  if (getsockopt (ns->fd, SOL_SOCKET, SO_SNDBUF, (char *) &oldbufsize, (socklen_t *) & buflen) == -1)
    oldbufsize = 0;

  if (oldbufsize < bufsize)
    if (setsockopt (ns->fd, SOL_SOCKET, SO_SNDBUF, (char *) &bufsize, sizeof (&bufsize)))
      LOG (llevError, "InitConnection: setsockopt unable to set output buf size to %d\n", bufsize);

  buflen = sizeof (oldbufsize);
  getsockopt (ns->fd, SOL_SOCKET, SO_SNDBUF, (char *) &oldbufsize, (socklen_t *) & buflen);
#ifdef ESRV_DEBUG
  LOG (llevDebug, "Socket buffer size now %d bytes\n", oldbufsize);
#endif

  ns->faceset = 0;
  ns->facecache = 0;
  ns->image2 = 0;
  ns->sound = 0;
  ns->exp64 = 0;
  ns->monitor_spells = 0;
  ns->mapmode = Map0Cmd;
  ns->darkness = 1;
  ns->status = Ns_Add;
  ns->mapx = 11;
  ns->mapy = 11;
  ns->newmapcmd = 0;
  ns->itemcmd = 1;              /* Default is version item1 command */
  ns->ext_mapinfos = 0;         /*extendedmapinfo datas */
  ns->EMI_smooth = 0;
  ns->look_position = 0;
  ns->update_look = 0;
  ns->has_readable_type = 0;
  ns->supported_readables = 0;
  ns->monitor_spells = 0;
  ns->mapinfocmd = 0;
  ns->extcmd = 0;
  ns->extmap = 0;

  /* we should really do some checking here - if total clients overflows
   * we need to do something more intelligent, because client id's will start
   * duplicating (not likely in normal cases, but malicous attacks that
   * just open and close connections could get this total up.
   */
  ns->inbuf_len = 0;

  /* Basic initialization. Needed because we do a check in
   * HandleClient for oldsocketmode without checking the
   * length of data.
   */
  memset (&ns->lastmap, 0, sizeof (struct Map));
  memset (ns->faces_sent, 0, ns->faces_sent_len * sizeof (*ns->faces_sent));
  memset (&ns->anims_sent, 0, sizeof (ns->anims_sent));
  memset (&ns->stats, 0, sizeof (struct statsinfo));
  /* Do this so we don't send a face command for the client for
   * this face.  Face 0 is sent to the client to say clear
   * face information.
   */
  ns->faces_sent[0] = NS_FACESENT_FACE;

  ns->outputbuffer.start = 0;
  ns->outputbuffer.len = 0;
  ns->can_write = 1;
  ns->password_fails = 0;

  ns->current_map = 0;
  ns->current_x = 0;
  ns->current_y = 0;
  ns->client[0] = 0;
  ns->buggy_mapscroll = 0;

  ns->sent_scroll = 0;
  ns->host = strdup_local (from_ip);

  {
    SockList sl (MAXSOCKBUF);

    sl.printf ("version %d %d %s\n", VERSION_CS, VERSION_SC, VERSION_INFO);
    Send_With_Handling (ns, &sl);
    sl.free ();
  }

#ifdef CS_LOGSTATS
  if (socket_info.nconns > cst_tot.max_conn)
    cst_tot.max_conn = socket_info.nconns;
  if (socket_info.nconns > cst_lst.max_conn)
    cst_lst.max_conn = socket_info.nconns;
#endif
}


/** This sets up the socket and reads all the image information into memory. */
void
init_ericserver (void)
{
  struct sockaddr_in insock;
  struct protoent *protox;
  struct linger linger_opt;

  socket_info.max_filedescriptor = sysconf (_SC_OPEN_MAX);

  socket_info.timeout.tv_sec = 0;
  socket_info.timeout.tv_usec = 0;
  socket_info.nconns = 0;

#ifdef CS_LOGSTATS
  memset (&cst_tot, 0, sizeof (CS_Stats));
  memset (&cst_lst, 0, sizeof (CS_Stats));
  cst_tot.time_start = time (NULL);
  cst_lst.time_start = time (NULL);
#endif

  LOG (llevDebug, "Initialize new client/server data\n");
  socket_info.nconns = 1;
  init_sockets = (NewSocket *) malloc (sizeof (NewSocket));
  init_sockets[0].faces_sent = NULL;    /* unused */
  socket_info.allocated_sockets = 1;

  protox = getprotobyname ("tcp");
  if (protox == NULL)
    {
      LOG (llevError, "init_ericserver: Error getting protox\n");
      return;
    }

  init_sockets[0].fd = socket (PF_INET, SOCK_STREAM, protox->p_proto);
  if (init_sockets[0].fd == -1)
    {
      LOG (llevError, "Cannot create socket: %s\n", strerror (errno));
      exit (-1);
    }

  insock.sin_family = AF_INET;
  insock.sin_port = htons (settings.csport);
  insock.sin_addr.s_addr = htonl (INADDR_ANY);

  linger_opt.l_onoff = 0;
  linger_opt.l_linger = 0;
  if (setsockopt (init_sockets[0].fd, SOL_SOCKET, SO_LINGER, (char *) &linger_opt, sizeof (struct linger)))
    LOG (llevError, "Cannot setsockopt(SO_LINGER): %s\n", strerror (errno));

  {
    int tmp = 1;

    if (setsockopt (init_sockets[0].fd, SOL_SOCKET, SO_REUSEADDR, &tmp, sizeof (tmp)))
      LOG (llevError, "Cannot setsockopt(SO_REUSEADDR): %s\n", strerror (errno));
  }

  if (bind (init_sockets[0].fd, (struct sockaddr *) &insock, sizeof (insock)) == (-1))
    {
      LOG (llevError, "Cannot bind socket to port %d: %s\n", ntohs (insock.sin_port), strerror (errno));
      close (init_sockets[0].fd);
      exit (-1);
    }

  if (listen (init_sockets[0].fd, 5) == (-1))
    {
      LOG (llevError, "Cannot listen on socket: %s\n", strerror (errno));
      close (init_sockets[0].fd);
      exit (-1);
    }

  init_sockets[0].status = Ns_Add;
  read_client_images ();
}


/*******************************************************************************
 *
 * Start of functions dealing with freeing of the data.
 *
 ******************************************************************************/

/** Free's all the memory that ericserver allocates. */
void
free_all_newserver (void)
{
  LOG (llevDebug, "Freeing all new client/server information.\n");
  free_socket_images ();
  free (init_sockets);
}

/**
 * Frees a socket.
 * Basically, all we need to do here is free all data structures that
 * might be associated with the socket.  It is up to the caller to
 * update the list
 */

void
free_newsocket (NewSocket *ns)
{
  close (ns->fd);

  if (ns->stats.range)
    free (ns->stats.range);

  if (ns->stats.title)
    free (ns->stats.title);

  free (ns->host);
}

/** Sends the 'goodbye' command to the player, and closes connection. */
void
final_free_player (player *pl)
{
  pl->socket.send_packet ("goodbye");
  free_newsocket (&pl->socket);
  free_player (pl);
}