/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2007 INRIA

 * All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * 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

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#include "ns3/debug.h"

#include "ns3/node.h"

#include "ns3/inet-socket-address.h"

#include "udp-socket.h"

#include "udp-l4-protocol.h"

#include "ipv4-end-point.h"

#include "ipv4-l4-demux.h"

#include "ns3/ipv4.h"

NS_DEBUG_COMPONENT_DEFINE ("UdpSocket");

namespace ns3 {

UdpSocket::UdpSocket (Ptr<Node> node, Ptr<UdpL4Protocol> udp)

  : m_endPoint (0),

    m_node (node),

    m_udp (udp),

    m_errno (ERROR_NOTERROR),

    m_shutdownSend (false),

    m_shutdownRecv (false),

    m_connected (false)

{

  NS_DEBUG("UdpSocket::UdpSocket ()");

}

UdpSocket::~UdpSocket ()

{

  NS_DEBUG("UdpSocket::~UdpSocket ()");

  m_node = 0;

  if (m_endPoint != 0)

    {

      NS_ASSERT (m_udp != 0);

      /**

       * Note that this piece of code is a bit tricky:

       * when DeAllocate is called, it will call into

       * Ipv4EndPointDemux::Deallocate which triggers

       * a delete of the associated endPoint which triggers

       * in turn a call to the method ::Destroy below

       * will will zero the m_endPoint field.

       */

      NS_ASSERT (m_endPoint != 0);

      m_udp->DeAllocate (m_endPoint);

      NS_ASSERT (m_endPoint == 0);

    }

  m_udp = 0;

}

enum Socket::SocketErrno

UdpSocket::GetErrno (void) const

{

  NS_DEBUG("UdpSocket::GetErrno ()");

  return m_errno;

}

Ptr<Node>

UdpSocket::GetNode (void) const

{

  NS_DEBUG("UdpSocket::GetNode ()");

  return m_node;

}

void 

UdpSocket::Destroy (void)

{

  NS_DEBUG("UdpSocket::Destroy ()");

  m_node = 0;

  m_endPoint = 0;

  m_udp = 0;

}

int

UdpSocket::FinishBind (void)

{

  NS_DEBUG("UdpSocket::FinishBind ()");

  if (m_endPoint == 0)

    {

      return -1;

    }

  m_endPoint->SetRxCallback (MakeCallback (&UdpSocket::ForwardUp, this));

  m_endPoint->SetDestroyCallback (MakeCallback (&UdpSocket::Destroy, this));

  return 0;

}

int

UdpSocket::Bind (void)

{

  NS_DEBUG("UdpSocket::Bind ()");

  m_endPoint = m_udp->Allocate ();

  return FinishBind ();

}

int 

UdpSocket::Bind (const Address &address)

{

  NS_DEBUG("UdpSocket::Bind (" << address << ")");

  if (!InetSocketAddress::IsMatchingType (address))

    {

      NS_DEBUG("UdpSocket::Bind (): Not IsMatchingType");

      return ERROR_INVAL;

    }

  InetSocketAddress transport = InetSocketAddress::ConvertFrom (address);

  Ipv4Address ipv4 = transport.GetIpv4 ();

  uint16_t port = transport.GetPort ();

  if (ipv4 == Ipv4Address::GetAny () && port == 0)

    {

      m_endPoint = m_udp->Allocate ();

    }

  else if (ipv4 == Ipv4Address::GetAny () && port != 0)

    {

      m_endPoint = m_udp->Allocate (port);

    }

  else if (ipv4 != Ipv4Address::GetAny () && port == 0)

    {

      m_endPoint = m_udp->Allocate (ipv4);

    }

  else if (ipv4 != Ipv4Address::GetAny () && port != 0)

    {

      m_endPoint = m_udp->Allocate (ipv4, port);

    }

  return FinishBind ();

}

int 

UdpSocket::ShutdownSend (void)

{

  NS_DEBUG("UdpSocket::ShutDownSend ()");

  m_shutdownSend = true;

  return 0;

}

int 

UdpSocket::ShutdownRecv (void)

{

  NS_DEBUG("UdpSocket::ShutDownRecv ()");

  m_shutdownRecv = false;

  return 0;

}

int

UdpSocket::Close(void)

{

  NS_DEBUG("UdpSocket::Close ()");

  NotifyCloseCompleted ();

  return 0;

}

int

UdpSocket::Connect(const Address & address)

{

  InetSocketAddress transport = InetSocketAddress::ConvertFrom (address);

  m_defaultAddress = transport.GetIpv4 ();

  m_defaultPort = transport.GetPort ();

  NotifyConnectionSucceeded ();

  m_connected = true;

  Ptr<Ipv4> ipv4;

  ipv4 = m_node->QueryInterface<Ipv4> (Ipv4::iid);

  m_endPoint->SetLocalAddress (ipv4->GetSourceAddress(m_defaultAddress));

  return 0;

}

int 

UdpSocket::Send (const Packet &p)

{

  NS_DEBUG("UdpSocket::Send (" << &p << ")");

  if (!m_connected)

    {

      m_errno = ERROR_NOTCONN;

      return -1;

    }

  return DoSendTo (p, m_defaultAddress, m_defaultPort);

}

int

UdpSocket::DoSendTo (const Packet &p, const Address &address)

{

  NS_DEBUG("UdpSocket::DoSendTo (" << &p << ", " << address << ")");

  InetSocketAddress transport = InetSocketAddress::ConvertFrom (address);

  Ipv4Address ipv4 = transport.GetIpv4 ();

  uint16_t port = transport.GetPort ();

  return DoSendTo (p, ipv4, port);

}

int

UdpSocket::DoSendTo (const Packet &p, Ipv4Address ipv4, uint16_t port)

{

  NS_DEBUG("UdpSocket::DoSendTo (" << &p << ", " << ipv4 << ", " <<

    port << ")");

  if (m_endPoint == 0)

    {

      if (Bind () == -1)

	{

          NS_ASSERT (m_endPoint == 0);

	  return -1;

	}

      NS_ASSERT (m_endPoint != 0);

    }

  if (m_shutdownSend)

    {

      m_errno = ERROR_SHUTDOWN;

      return -1;

    }

  NS_DEBUG("UdpSocket::DoSendTo (): Send to UDP");

  m_udp->Send (p, m_endPoint->GetLocalAddress (), ipv4,

		   m_endPoint->GetLocalPort (), port);

  NotifyDataSent (p.GetSize ());

  return 0;

}

int 

UdpSocket::SendTo(const Address &address, const Packet &p)

{

  NS_DEBUG("UdpSocket::SendTo (" << address << ", " << &p << ")");

  if (m_connected)

    {

      m_errno = ERROR_ISCONN;

      return -1;

    }

  InetSocketAddress transport = InetSocketAddress::ConvertFrom (address);

  Ipv4Address ipv4 = transport.GetIpv4 ();

  uint16_t port = transport.GetPort ();

  return DoSendTo (p, ipv4, port);

}

void 

UdpSocket::ForwardUp (const Packet &packet, Ipv4Address ipv4, uint16_t port)

{

  NS_DEBUG("UdpSocket::ForwardUp (" << &packet << ", " << ipv4 << ", " <<

    port << ")");

  if (m_shutdownRecv)

    {

      return;

    }

  Address address = InetSocketAddress (ipv4, port);

  Packet p = packet;

  NotifyDataReceived (p, address);

}