/*  Project nGenEx
    Destroyer Studios LLC
    Copyright © 1997-2004. All Rights Reserved.

    SUBSYSTEM:    NetEx.lib
    FILE:         NetSock.cpp
    AUTHOR:       John DiCamillo


    OVERVIEW
    ========
    Network (IP) Socket Wrapper Implementation
*/


// WINSOCK2.H MUST COME FIRST!!
#include <winsock2.h>

#include "MemDebug.h"
#include "NetSock.h"
#include "NetLayer.h"

// +-------------------------------------------------------------------+

/**
 * Server-side socket constructor
 */
NetSock::NetSock(bool str)
   : stream(str), closed(false), stat(0), current_timeout(9999)
{
   if (stream)
      s = ::socket(AF_INET, SOCK_STREAM, 0);
   else
      s = ::socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
}

/**
 * Server-side socket constructor
 *
 * PRIVATE: used only by the accept call to build a socket for
 * a client connection to this server
 */
NetSock::NetSock(SOCKET sock, bool str)
   : s(sock), stream(str), closed(false), stat(0), current_timeout(9999)
{ }

/**
 * Client-side socket constructor
 *
 * Will connect to server at "addr"
 */
NetSock::NetSock(const NetAddr& addr, bool str)
   : stream(str), closed(false), stat(0), current_timeout(9999)
{
   if (stream)
      s = ::socket(AF_INET, SOCK_STREAM, 0);
   else
      s = ::socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);

   connect(addr);
}

NetSock::~NetSock()
{
   close();
}

// +--------------------------------------------------------------------+

int
NetSock::bind(const NetAddr& addr)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   return stat = ::bind(s, addr.GetSockAddr(), addr.GetSockAddrLength());
}

int
NetSock::connect(const NetAddr& addr)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   return stat = ::connect(s, addr.GetSockAddr(), addr.GetSockAddrLength());
}

int
NetSock::listen(int max_connections)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   return stat = ::listen(s, max_connections);
}

NetSock*
NetSock::accept(NetAddr* addr)
{
   if (closed || s == INVALID_SOCKET) return 0;

   SOCKET conn = INVALID_SOCKET;

   if (addr) {
      sockaddr a;
      int      asize = sizeof(a);
   
      conn = ::accept(s, &a, &asize);

      if (conn != INVALID_SOCKET && asize > 0) {
         addr->SetSockAddr(&a, asize);
      }
   }
   else {
      conn = ::accept(s, 0, 0);
   }

   if (conn == INVALID_SOCKET)
      return 0;

   return new(__FILE__,__LINE__) NetSock(conn, stream);
}

// +--------------------------------------------------------------------+
 
int
NetSock::available()
{
   if (closed || s == INVALID_SOCKET) return 0;
 
   DWORD nbytes = 0;
   if (::ioctlsocket(s, FIONREAD, &nbytes) == 0)
      return (int) nbytes;

   return 0;
}
 
// +--------------------------------------------------------------------+

int
NetSock::send(Text msg)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   return stat = ::send(s, msg.data(), msg.length(), 0);
}

Text
NetSock::recv()
{
   if (closed || s == INVALID_SOCKET) return "";

   static char rbuf[8192];
   int         rlen = -1;

   if (stream) {
      rlen = ::recv(s, rbuf, sizeof(rbuf), 0);
   }
   else {
      rlen = ::recvfrom(s, rbuf, sizeof(rbuf), 0, 0, 0);
   }

   if (rlen < 0) {
      stat = NetLayer::GetLastError();

      switch (stat) {
      case WSAENETDOWN:
      case WSAENETRESET:
      case WSAEINTR:
      case WSAESHUTDOWN:
      case WSAECONNABORTED:
      case WSAECONNRESET:
      case WSAETIMEDOUT:
            close();
            break;

      case WSAEWOULDBLOCK:
            stat = WSAEWOULDBLOCK;
            break;
      }

      return Text();
   }

   else if (rlen == 0) {
      return Text();
   }

   return Text(rbuf, rlen);
}


// +--------------------------------------------------------------------+

int
NetSock::sendto(Text msg, const NetAddr& dest)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   return stat = ::sendto(s, msg.data(), msg.length(),
                          0, dest.GetSockAddr(), dest.GetSockAddrLength());
}

Text
NetSock::recvfrom(NetAddr* a)
{
   if (closed || s == INVALID_SOCKET) return "";

   static char rbuf[4096];
   int rlen = 0;

   if (a) {
      int addrlen = a->GetSockAddrLength();
      rlen = ::recvfrom(s, rbuf, sizeof(rbuf), 0, a->GetSockAddr(), &addrlen);
      a->InitFromSockAddr();
   }
   else {
      rlen = ::recvfrom(s, rbuf, sizeof(rbuf), 0, 0, 0);
   }

   if (rlen < 0) {
      stat = NetLayer::GetLastError();
      return Text();
   }

   else if (rlen == 0) {
      return Text();
   }

   return Text(rbuf, rlen);
}

// +--------------------------------------------------------------------+

int
NetSock::select(SELECT_TYPE t, long seconds, long microseconds)
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;

   FD_SET fd;
   ZeroMemory(&fd, sizeof(fd));

   FD_SET(s, &fd);
   TIMEVAL  timeval = {seconds, microseconds};
   TIMEVAL* timeout = &timeval;

   if (t == SELECT_READ)
      return stat = ::select(1, &fd, 0, 0, timeout);

   else if (t == SELECT_WRITE)
      return stat = ::select(1, 0, &fd, 0, timeout);

   else if (t == (SELECT_READ|SELECT_WRITE))
      return stat = ::select(1, &fd, &fd, 0, timeout);

   return 0;
}

// +--------------------------------------------------------------------+

int
NetSock::set_timeout(int msecs)
{
   if (closed || s == INVALID_SOCKET) return 0;
   if (msecs == current_timeout)      return 1;
 
   // zero timeout means non-blocking
   if (msecs == 0) {
      u_long nonblocking = 1;
      if (::ioctlsocket(s, FIONBIO, &nonblocking) == SOCKET_ERROR) {
         stat = NetLayer::GetLastError();
         return stat;
      }
   }
 
   // non-zero timeout means blocking
   else {
      if (current_timeout == 0) {
         u_long nonblocking = 0;   // disable non-blocking
         if (::ioctlsocket(s, FIONBIO, &nonblocking) == SOCKET_ERROR) {
            stat = NetLayer::GetLastError();
            return stat;
         }
      }

      // max timeout means infinite wait
      if (msecs >= NET_MAX_TIMEOUT) {
         int maxto = 0;
         ::setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (char*) &maxto, sizeof(maxto));
         ::setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, (char*) &maxto, sizeof(maxto));
      }
 
      // otherwise, set the timeout
      else {
         ::setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (char*) &msecs, sizeof(msecs));
         ::setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, (char*) &msecs, sizeof(msecs));
      }
   }
 
   current_timeout = msecs;
   return 1;
}

// +--------------------------------------------------------------------+

int
NetSock::shutdown_input()
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   ::shutdown(s, SD_RECEIVE);
   return 0;
}

// +--------------------------------------------------------------------+

int
NetSock::shutdown_output()
{
   if (closed || s == INVALID_SOCKET) return INVALID_SOCKET;
   ::shutdown(s, SD_SEND);
   return 0;
}

// +--------------------------------------------------------------------+

int
NetSock::close()
{
   if (s != INVALID_SOCKET && !closed) {
      ::shutdown(s, SD_BOTH);
      ::closesocket(s);

      closed = true;
   }

   return 0;
}

// +--------------------------------------------------------------------+

DWORD
NetSock::max_packet_size() const
{
   DWORD size = 0;
   int   len  = sizeof(size);

   ::getsockopt(s, SOL_SOCKET, 0x2003, (char*) &size, &len);

   return size;
}