/*
 * ClientConnection.cpp
 *
 * Copyright (C) 2008 Matthias Schiffer <matthias@gamezock.de>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include "ClientConnection.h"
#include "IPAddress.h"
#include <cstring>
#include <cerrno>
#include <sys/socket.h>
#include <fcntl.h>

namespace Mad {
namespace Net {

void ClientConnection::connectionHeaderReceiveHandler(const void *data, unsigned long length) {
  if(length != sizeof(ConnectionHeader))
    // Error... disconnect
    return;

  const ConnectionHeader *header = reinterpret_cast<const ConnectionHeader*>(data);

  if(header->m != 'M' || header->a != 'A' || header->d != 'D')
    // Error... disconnect
    return;

  if(header->protVerMin != 1)
    // Unsupported protocol... disconnect
    return;

  enterReceiveLoop();
}

void ClientConnection::connectionHeader() {
  ConnectionHeader header = {'M', 'A', 'D', daemon ? 'D' : 'C', 0, 1, 1, 1};

  rawSend(reinterpret_cast<unsigned char*>(&header), sizeof(header));
  rawReceive(sizeof(ConnectionHeader), sigc::mem_fun(this, &ClientConnection::connectionHeaderReceiveHandler));
}

void ClientConnection::connect(const IPAddress &address, bool daemon0) throw(ConnectionException) {
  daemon = daemon0;

  if(isConnected())
    disconnect();

  sock = socket(PF_INET, SOCK_STREAM, 0);
  if(sock < 0)
    throw ConnectionException("socket()", std::strerror(errno));

  peer = new IPAddress(address);

  if(::connect(sock, peer->getSockAddr(), peer->getSockAddrLength()) < 0) {
    close(sock);
    delete peer;
    peer = 0;
    throw ConnectionException("connect()", std::strerror(errno));
  }

  // Set non-blocking flag
  int flags = fcntl(sock, F_GETFL, 0);

  if(flags < 0) {
    close(sock);

    throw ConnectionException("fcntl()", std::strerror(errno));
  }

  fcntl(sock, F_SETFL, flags | O_NONBLOCK);

  // Don't linger
  struct linger linger = {1, 0};
  setsockopt(sock, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger));

  gnutls_init(&session, GNUTLS_CLIENT);

  gnutls_set_default_priority(session);

  const int kx_list[] = {GNUTLS_KX_ANON_DH, 0};
  gnutls_kx_set_priority(session, kx_list);

  gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);

  gnutls_transport_set_lowat(session, 0);
  gnutls_transport_set_ptr(session, reinterpret_cast<gnutls_transport_ptr_t>(sock));

  handshake();
}

}
}