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

/*

 * Copyright (c) 2007-2009 Strasbourg University

 *

 * 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: Sebastien Vincent <vincent@clarinet.u-strasbg.fr>

 */

#include "ipv6-end-point-demux.h"

#include "ipv6-end-point.h"

#include "ns3/log.h"

namespace ns3

{

NS_LOG_COMPONENT_DEFINE ("Ipv6EndPointDemux");

Ipv6EndPointDemux::Ipv6EndPointDemux ()

  : m_ephemeral (49152)

{

  NS_LOG_FUNCTION_NOARGS ();

}

Ipv6EndPointDemux::~Ipv6EndPointDemux ()

{

  NS_LOG_FUNCTION_NOARGS ();

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    Ipv6EndPoint *endPoint = *i;

    delete endPoint;

  }

  m_endPoints.clear ();

}

bool Ipv6EndPointDemux::LookupPortLocal (uint16_t port)

{

  NS_LOG_FUNCTION (this << port);

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    if ((*i)->GetLocalPort  () == port) 

    {

      return true;

    }

  }

  return false;

}

bool Ipv6EndPointDemux::LookupLocal (Ipv6Address addr, uint16_t port)

{

  NS_LOG_FUNCTION (this << addr << port);

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    if ((*i)->GetLocalPort () == port &&

        (*i)->GetLocalAddress () == addr) 

    {

      return true;

    }

  }

  return false;

}

Ipv6EndPoint* Ipv6EndPointDemux::Allocate ()

{

  NS_LOG_FUNCTION_NOARGS ();

  uint16_t port = AllocateEphemeralPort ();

  if (port == 0) 

  {

    NS_LOG_WARN ("Ephemeral port allocation failed.");

    return 0;

  }

  Ipv6EndPoint *endPoint = new Ipv6EndPoint (Ipv6Address::GetAny (), port);

  m_endPoints.push_back (endPoint);

  NS_LOG_DEBUG ("Now have >>" << m_endPoints.size () << "<< endpoints.");

  return endPoint;

}

Ipv6EndPoint* Ipv6EndPointDemux::Allocate (Ipv6Address address)

{

  NS_LOG_FUNCTION (this << address);

  uint16_t port = AllocateEphemeralPort ();

  if (port == 0) 

  {

    NS_LOG_WARN ("Ephemeral port allocation failed.");

    return 0;

  }

  Ipv6EndPoint *endPoint = new Ipv6EndPoint (address, port);

  m_endPoints.push_back (endPoint);

  NS_LOG_DEBUG ("Now have >>" << m_endPoints.size () << "<< endpoints.");

  return endPoint;

}

Ipv6EndPoint* Ipv6EndPointDemux::Allocate (uint16_t port)

{

  NS_LOG_FUNCTION (this <<  port);

  return Allocate (Ipv6Address::GetAny (), port);

}

Ipv6EndPoint* Ipv6EndPointDemux::Allocate (Ipv6Address address, uint16_t port)

{

  NS_LOG_FUNCTION (this << address << port);

  if (LookupLocal (address, port)) 

  {

    NS_LOG_WARN ("Duplicate address/port; failing.");

    return 0;

  }

  Ipv6EndPoint *endPoint = new Ipv6EndPoint (address, port);

  m_endPoints.push_back (endPoint);

  NS_LOG_DEBUG ("Now have >>" << m_endPoints.size () << "<< endpoints.");

  return endPoint;

}

Ipv6EndPoint* Ipv6EndPointDemux::Allocate (Ipv6Address localAddress, uint16_t localPort,

    Ipv6Address peerAddress, uint16_t peerPort)

{

  NS_LOG_FUNCTION (this << localAddress << localPort << peerAddress << peerPort);

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    if ((*i)->GetLocalPort () == localPort &&

        (*i)->GetLocalAddress () == localAddress &&

        (*i)->GetPeerPort () == peerPort &&

        (*i)->GetPeerAddress () == peerAddress) 

    {

      NS_LOG_WARN ("No way we can allocate this end-point.");

      /* no way we can allocate this end-point. */

      return 0;

    }

  }

  Ipv6EndPoint *endPoint = new Ipv6EndPoint (localAddress, localPort);

  endPoint->SetPeer (peerAddress, peerPort);

  m_endPoints.push_back (endPoint);

  NS_LOG_DEBUG ("Now have >>" << m_endPoints.size () << "<< endpoints.");

  return endPoint;

}

void Ipv6EndPointDemux::DeAllocate (Ipv6EndPoint *endPoint)

{

  NS_LOG_FUNCTION_NOARGS ();

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    if (*i == endPoint)

    {

      delete endPoint;

      m_endPoints.erase (i);

      break;

    }

  }

}

/*

 * If we have an exact match, we return it.

 * Otherwise, if we find a generic match, we return it.

 * Otherwise, we return 0.

 */

Ipv6EndPointDemux::EndPoints Ipv6EndPointDemux::Lookup (Ipv6Address daddr, uint16_t dport, 

                                                        Ipv6Address saddr, uint16_t sport,

                                                        Ptr<Ipv6Interface> incomingInterface)

{

  NS_LOG_FUNCTION (this << daddr << dport << saddr << sport << incomingInterface);

  EndPoints retval1; /* Matches exact on local port, wildcards on others */

  EndPoints retval2; /* Matches exact on local port/adder, wildcards on others */

  EndPoints retval3; /* Matches all but local address */

  EndPoints retval4; /* Exact match on all 4 */

  NS_LOG_DEBUG ("Looking up endpoint for destination address " << daddr);

  for (EndPointsI i = m_endPoints.begin (); i != m_endPoints.end (); i++) 

  {

    Ipv6EndPoint* endP = *i;

    NS_LOG_DEBUG ("Looking at endpoint dport=" << endP->GetLocalPort ()

        << " daddr=" << endP->GetLocalAddress ()

        << " sport=" << endP->GetPeerPort ()

        << " saddr=" << endP->GetPeerAddress ());

    if (endP->GetLocalPort () != dport) 

    {

      NS_LOG_LOGIC ("Skipping endpoint " << &endP

          << " because endpoint dport "

          << endP->GetLocalPort ()

          << " does not match packet dport " << dport);

      continue;

    }

/*    Ipv6Address incomingInterfaceAddr = incomingInterface->GetAddress (); */

    NS_LOG_DEBUG ("dest addr " << daddr);

    bool localAddressMatchesWildCard = endP->GetLocalAddress () == Ipv6Address::GetAny ();

    bool localAddressMatchesExact = endP->GetLocalAddress () == daddr;

    bool localAddressMatchesAllRouters = endP->GetLocalAddress () == Ipv6Address::GetAllRoutersMulticast ();

    /* if no match here, keep looking */

    if (!(localAddressMatchesExact || localAddressMatchesWildCard))

      continue; 

    bool remotePeerMatchesExact = endP->GetPeerPort () == sport;

    bool remotePeerMatchesWildCard = endP->GetPeerPort () == 0;

    bool remoteAddressMatchesExact = endP->GetPeerAddress () == saddr;

    bool remoteAddressMatchesWildCard = endP->GetPeerAddress () == Ipv6Address::GetAny ();

    /* If remote does not match either with exact or wildcard,i

       skip this one */

    if (!(remotePeerMatchesExact || remotePeerMatchesWildCard))

      continue;

    if (!(remoteAddressMatchesExact || remoteAddressMatchesWildCard))

      continue;

    /* Now figure out which return list to add this one to */

    if (localAddressMatchesWildCard &&

        remotePeerMatchesWildCard && 

        remoteAddressMatchesWildCard)

    { /* Only local port matches exactly */

      retval1.push_back (endP);

    }

    if ((localAddressMatchesExact || (localAddressMatchesAllRouters))&&

        remotePeerMatchesWildCard &&

        remoteAddressMatchesWildCard)

    { /* Only local port and local address matches exactly */

      retval2.push_back (endP);

    }

    if (localAddressMatchesWildCard &&

        remotePeerMatchesExact &&

        remoteAddressMatchesExact)

    { /* All but local address */

      retval3.push_back (endP);

    }

    if (localAddressMatchesExact &&

        remotePeerMatchesExact &&

        remoteAddressMatchesExact)

    { /* All 4 match */

      retval4.push_back (endP);

    }

  }

  /* Here we find the most exact match */

  if (!retval4.empty ()) return retval4;

  if (!retval3.empty ()) return retval3;

  if (!retval2.empty ()) return retval2;

  return retval1;  /* might be empty if no matches */

}

Ipv6EndPoint* Ipv6EndPointDemux::SimpleLookup (Ipv6Address dst, uint16_t dport, Ipv6Address src, uint16_t sport)

{

  uint32_t genericity = 3;

  Ipv6EndPoint *generic = 0;

  for (EndPointsI i = m_endPoints.begin () ; i != m_endPoints.end () ; i++)

  {

    uint32_t tmp = 0;

    if ((*i)->GetLocalPort () != dport)

    {

      continue;

    }

    if ((*i)->GetLocalAddress () == dst && (*i)->GetPeerPort () == sport &&

        (*i)->GetPeerAddress () == src)

    {

      /* this is an exact match. */

      return *i;

    }

    if ((*i)->GetLocalAddress () == Ipv6Address::GetAny ())

    {

      tmp ++;

    }

    if ((*i)->GetPeerAddress () == Ipv6Address::GetAny ())

    {

      tmp ++;

    }

    if (tmp < genericity)

    {

      generic = (*i);

      genericity = tmp;

    }

  }

  return generic;

}

uint16_t Ipv6EndPointDemux::AllocateEphemeralPort ()

{

  NS_LOG_FUNCTION_NOARGS ();

  uint16_t port = m_ephemeral;

  do 

  {

    port++;

    if (port == 65535) 

    {

      port = 49152;

    }

    if (!LookupPortLocal (port)) 

    {

      return port;

    }

  } while (port != m_ephemeral);

  return 0;

}

Ipv6EndPointDemux::EndPoints Ipv6EndPointDemux::GetEndPoints () const

{

  return m_endPoints;

}

} /* namespace ns3 */