/*
Copyright (C) 1996-1997 Id Software, Inc.

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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// net_mpath.c

#include <dpmi.h>
#include "quakedef.h"
#include "mpdosock.h"

short flat_selector;

int WSAGetLastError(void);
void sockets_flush(void);

extern cvar_t hostname;

#define MAXHOSTNAMELEN    256

static int net_acceptsocket = -1;   // socket for fielding new connections
static int net_controlsocket;
static int net_broadcastsocket = 0;
//static qboolean ifbcastinit = false;
static struct qsockaddr broadcastaddr;

static unsigned long myAddr;

#include "net_mp.h"


//=============================================================================

int MPATH_Init (void)
{
  int   i;
  struct hostent *local = NULL;
  char  buff[MAXHOSTNAMELEN];
  struct qsockaddr addr;
  char  *p;

  if (COM_CheckParm ("-mpath") == 0)
    return -1;

   flat_selector = __dpmi_allocate_ldt_descriptors(1);
   if (flat_selector == -1) {
      Con_Printf("MPATH_Init: Can't get flat selector\n");
      return -1;
   }
   if (__dpmi_set_segment_base_address(flat_selector, 0) == -1) {
      Con_Printf("MPATH_Init: Can't seg flat base!\n");
      return -1;
   }
   if (__dpmi_set_segment_limit(flat_selector, 0xffffffff) == -1) {
      Con_Printf("MPATH_Init: Can't set segment limit\n");
      return -1;
   }
  // determine my name & address
  if (gethostname(buff, MAXHOSTNAMELEN) == 0)
    local = gethostbyname(buff);
  if (local)
  {
    myAddr = *(int *)local->h_addr_list[0];

    // if the quake hostname isn't set, set it to the machine name
    if (Q_strcmp(hostname.string, "UNNAMED") == 0)
    {
      // see if it's a text IP address (well, close enough)
      for (p = buff; *p; p++)
        if ((*p < '0' || *p > '9') && *p != '.')
          break;

      // if it is a real name, strip off the domain; we only want the host
      if (*p)
      {
        for (i = 0; i < 15; i++)
          if (buff[i] == '.')
            break;
        buff[i] = 0;
      }
      Cvar_Set ("hostname", buff);
    }
  }

  if ((net_controlsocket = MPATH_OpenSocket (0)) == -1)
    Sys_Error("MPATH_Init: Unable to open control socket\n");

  ((struct sockaddr_in *)&broadcastaddr)->sin_family = AF_INET;
  ((struct sockaddr_in *)&broadcastaddr)->sin_addr.s_addr = INADDR_BROADCAST;
  ((struct sockaddr_in *)&broadcastaddr)->sin_port = htons(net_hostport);

  MPATH_GetSocketAddr (net_controlsocket, &addr);
  Q_strcpy(my_tcpip_address,  MPATH_AddrToString (&addr));
  p = Q_strrchr (my_tcpip_address, ':');
  if (p)
    *p = 0;

  Con_Printf("MPath Initialized\n");
  tcpipAvailable = true;

  return net_controlsocket;
}

//=============================================================================

void MPATH_Shutdown (void)
{
  MPATH_Listen (false);
  MPATH_CloseSocket (net_controlsocket);
}

//=============================================================================

void MPATH_Listen (qboolean state)
{
  // enable listening
  if (state)
  {
    if (net_acceptsocket != -1)
      return;
    if ((net_acceptsocket = MPATH_OpenSocket (net_hostport)) == -1)
      Sys_Error ("MPATH_Listen: Unable to open accept socket\n");
    return;
  }

  // disable listening
  if (net_acceptsocket == -1)
    return;
  MPATH_CloseSocket (net_acceptsocket);
  net_acceptsocket = -1;
}

//=============================================================================

int MPATH_OpenSocket (int port)
{
  int newsocket;
  struct sockaddr_in address;
  u_long _true = 1;

  if ((newsocket = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
    return -1;

  if (ioctlsocket (newsocket, FIONBIO, &_true) == -1)
    goto ErrorReturn;

  address.sin_family = AF_INET;
  address.sin_addr.s_addr = INADDR_ANY;
  address.sin_port = htons(port);
  if( bind (newsocket, (void *)&address, sizeof(address)) == -1)
    goto ErrorReturn;

  return newsocket;

ErrorReturn:
  closesocket (newsocket);
  return -1;
}

//=============================================================================

int MPATH_CloseSocket (int socket)
{
  if (socket == net_broadcastsocket)
    net_broadcastsocket = 0;
  return closesocket (socket);
}


//=============================================================================
/*
============
PartialIPAddress

this lets you type only as much of the net address as required, using
the local network components to fill in the rest
============
*/
static int PartialIPAddress (char *in, struct qsockaddr *hostaddr)
{
  char buff[256];
  char *b;
  int addr;
  int num;
  int mask;
  int run;
  int port;
  
  buff[0] = '.';
  b = buff;
  strcpy(buff+1, in);
  if (buff[1] == '.')
    b++;

  addr = 0;
  mask=-1;
  while (*b == '.')
  {
    b++;
    num = 0;
    run = 0;
    while (!( *b < '0' || *b > '9'))
    {
      num = num*10 + *b++ - '0';
      if (++run > 3)
        return -1;
    }
    if ((*b < '0' || *b > '9') && *b != '.' && *b != ':' && *b != 0)
      return -1;
    if (num < 0 || num > 255)
      return -1;
    mask<<=8;
    addr = (addr<<8) + num;
  }
  
  if (*b++ == ':')
    port = Q_atoi(b);
  else
    port = net_hostport;

  hostaddr->sa_family = AF_INET;
  ((struct sockaddr_in *)hostaddr)->sin_port = htons((short)port);  
  ((struct sockaddr_in *)hostaddr)->sin_addr.s_addr = (myAddr & htonl(mask)) | htonl(addr);
  
  return 0;
}
//=============================================================================

int MPATH_Connect (int socket, struct qsockaddr *addr)
{
  return 0;
}

//=============================================================================

int MPATH_CheckNewConnections (void)
{
  char buf[4];

  if (net_acceptsocket == -1)
    return -1;

  if (recvfrom (net_acceptsocket, buf, 4, MSG_PEEK, NULL, NULL) > 0)
    return net_acceptsocket;
  return -1;
}

//=============================================================================

int MPATH_Read (int socket, byte *buf, int len, struct qsockaddr *addr)
{
  int addrlen = sizeof (struct qsockaddr);
  int ret;

  ret = recvfrom (socket, buf, len, 0, (struct sockaddr *)addr, &addrlen);
  if (ret == -1)
  {
    int errno = WSAGetLastError();

    if (errno == WSAEWOULDBLOCK || errno == WSAECONNREFUSED)
      return 0;

  }
  return ret;
}

//=============================================================================

int MPATH_MakeSocketBroadcastCapable (int socket)
{
  int i = 1;

  // make this socket broadcast capable
  if (setsockopt(socket, SOL_SOCKET, SO_BROADCAST, (char *)&i, sizeof(i)) < 0)
    return -1;
  net_broadcastsocket = socket;

  return 0;
}

//=============================================================================

int MPATH_Broadcast (int socket, byte *buf, int len)
{
  int ret;

  if (socket != net_broadcastsocket)
  {
    if (net_broadcastsocket != 0)
      Sys_Error("Attempted to use multiple broadcasts sockets\n");
    ret = MPATH_MakeSocketBroadcastCapable (socket);
    if (ret == -1)
    {
      Con_Printf("Unable to make socket broadcast capable\n");
      return ret;
    }
  }

  return MPATH_Write (socket, buf, len, &broadcastaddr);
}

//=============================================================================

int MPATH_Write (int socket, byte *buf, int len, struct qsockaddr *addr)
{
  int ret;

  ret = sendto (socket, buf, len, 0, (struct sockaddr *)addr, sizeof(struct qsockaddr));
  if (ret == -1)
    if (WSAGetLastError() == WSAEWOULDBLOCK)
      return 0;

  sockets_flush();

  return ret;
}

//=============================================================================

char *MPATH_AddrToString (struct qsockaddr *addr)
{
  static char buffer[22];
  int haddr;

  haddr = ntohl(((struct sockaddr_in *)addr)->sin_addr.s_addr);
  sprintf(buffer, "%d.%d.%d.%d:%d", (haddr >> 24) & 0xff, (haddr >> 16) & 0xff, (haddr >> 8) & 0xff, haddr & 0xff, ntohs(((struct sockaddr_in *)addr)->sin_port));
  return buffer;
}

//=============================================================================

int MPATH_StringToAddr (char *string, struct qsockaddr *addr)
{
  int ha1, ha2, ha3, ha4, hp;
  int ipaddr;

  sscanf(string, "%d.%d.%d.%d:%d", &ha1, &ha2, &ha3, &ha4, &hp);
  ipaddr = (ha1 << 24) | (ha2 << 16) | (ha3 << 8) | ha4;

  addr->sa_family = AF_INET;
  ((struct sockaddr_in *)addr)->sin_addr.s_addr = htonl(ipaddr);
  ((struct sockaddr_in *)addr)->sin_port = htons(hp);
  return 0;
}

//=============================================================================

int MPATH_GetSocketAddr (int socket, struct qsockaddr *addr)
{
  int addrlen = sizeof(struct qsockaddr);
  unsigned int a;

  Q_memset(addr, 0, sizeof(struct qsockaddr));
  getsockname(socket, (struct sockaddr *)addr, &addrlen);
  a = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
  if (a == 0 || a == inet_addr("127.0.0.1"))
    ((struct sockaddr_in *)addr)->sin_addr.s_addr = myAddr;

  return 0;
}

//=============================================================================

int MPATH_GetNameFromAddr (struct qsockaddr *addr, char *name)
{
  struct hostent *hostentry;

  hostentry = gethostbyaddr ((char *)&((struct sockaddr_in *)addr)->sin_addr, sizeof(struct in_addr), AF_INET);
  if (hostentry)
  {
    Q_strncpy (name, (char *)hostentry->h_name, NET_NAMELEN - 1);
    return 0;
  }

  Q_strcpy (name, MPATH_AddrToString (addr));
  return 0;
}

//=============================================================================

int MPATH_GetAddrFromName(char *name, struct qsockaddr *addr)
{
  struct hostent *hostentry;

  if (name[0] >= '0' && name[0] <= '9')
    return PartialIPAddress (name, addr);
  
  hostentry = gethostbyname (name);
  if (!hostentry)
    return -1;

  addr->sa_family = AF_INET;
  ((struct sockaddr_in *)addr)->sin_port = htons(net_hostport); 
  ((struct sockaddr_in *)addr)->sin_addr.s_addr = *(int *)hostentry->h_addr_list[0];

  return 0;
}

//=============================================================================

int MPATH_AddrCompare (struct qsockaddr *addr1, struct qsockaddr *addr2)
{
  if (addr1->sa_family != addr2->sa_family)
    return -1;

  if (((struct sockaddr_in *)addr1)->sin_addr.s_addr != ((struct sockaddr_in *)addr2)->sin_addr.s_addr)
    return -1;

  if (((struct sockaddr_in *)addr1)->sin_port != ((struct sockaddr_in *)addr2)->sin_port)
    return 1;

  return 0;
}

//=============================================================================

int MPATH_GetSocketPort (struct qsockaddr *addr)
{
  return ntohs(((struct sockaddr_in *)addr)->sin_port);
}


int MPATH_SetSocketPort (struct qsockaddr *addr, int port)
{
  ((struct sockaddr_in *)addr)->sin_port = htons(port);
  return 0;
}

//=============================================================================