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

/*

 * Copyright (c) 2009 IITP RAS

 *

 * 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: Kirill Andreev <andreev@iitp.ru>

 */

#include "flame-protocol.h"

#include "flame-header.h"

#include "ns3/llc-snap-header.h"

#include "ns3/log.h"

#include "ns3/simulator.h"

#include "ns3/packet.h"

#include "ns3/mesh-point-device.h"

#include "ns3/wifi-net-device.h"

#include "ns3/mesh-point-device.h"

#include "ns3/mesh-wifi-interface-mac.h"

#include "ns3/random-variable.h"

NS_LOG_COMPONENT_DEFINE ("FlameProtocol");

//-----------------------------------------------------------------------------

// FlameTag

//-----------------------------------------------------------------------------

NS_OBJECT_ENSURE_REGISTERED (FlameTag);

TypeId

FlameTag::GetTypeId ()

{

  static TypeId tid = TypeId ("ns3::flame::FlameTag") .SetParent<Tag> () .AddConstructor<FlameTag> ();

  return tid;

}

TypeId

FlameTag::GetInstanceTypeId () const

{

  return GetTypeId ();

}

uint32_t

FlameTag::GetSerializedSize () const

{

  return 12;

}

void

FlameTag::Serialize (TagBuffer i) const

{

  uint8_t buf[6];

  receiver.CopyTo (buf);

  for (int j = 0; j < 6; j++)

    {

      i.WriteU8 (buf[j]);

    }

  transmitter.CopyTo (buf);

  for (int j = 0; j < 6; j++)

    {

      i.WriteU8 (buf[j]);

    }

}

void

FlameTag::Deserialize (TagBuffer i)

{

  uint8_t buf[6];

  for (int j = 0; j < 6; j++)

    {

      buf[j] = i.ReadU8 ();

    }

  receiver.CopyFrom (buf);

  for (int j = 0; j < 6; j++)

    {

      buf[j] = i.ReadU8 ();

    }

  transmitter.CopyFrom (buf);

}

void

FlameTag::Print (std::ostream &os) const

{

  os << "receiver = " << receiver << ", transmitter = " << transmitter;

}

//-----------------------------------------------------------------------------

// FlameProtocol

//-----------------------------------------------------------------------------

TypeId

FlameProtocol::GetTypeId ()

{

  static TypeId tid = TypeId ("ns3::flame::FlameProtocol")

    .SetParent<MeshL2RoutingProtocol> ()

    .AddConstructor<FlameProtocol> ()

    .AddAttribute ( "BroadcastInterval",

                    "How often we must send broadcast packets",

                    TimeValue (Seconds (5)),

                    MakeTimeAccessor (

                        &FlameProtocol::m_broadcastInterval),

                    MakeTimeChecker ()

                    )

    .AddAttribute ( "MaxCost",

                    "Cost threshold after which packet will be dropeed",

                    UintegerValue (32),

                    MakeUintegerAccessor (

                        &FlameProtocol::m_maxCost),

                    MakeUintegerChecker<uint8_t> (3)

                    )

                    ;

  return tid;

}

FlameProtocol::FlameProtocol () :

  m_address (Mac48Address ()), m_broadcastInterval (Seconds (5)), m_lastBroadcast (Simulator::Now ()),

      m_maxCost (32), m_myLastSeqno (0), m_rtable (CreateObject<FlameRtable> ())

{

}

FlameProtocol::~FlameProtocol ()

{

}

void

FlameProtocol::DoDispose ()

{

}

bool

FlameProtocol::RequestRoute (uint32_t sourceIface, const Mac48Address source, const Mac48Address destination,

    Ptr<const Packet> const_packet, uint16_t protocolType, RouteReplyCallback routeReply)

{

  Ptr<Packet> packet = const_packet->Copy ();

  if (sourceIface == m_mp->GetIfIndex ())

    {

      //Packet from upper layer!

      FlameTag tag;

      if (packet->PeekPacketTag (tag))

        {

          NS_FATAL_ERROR ("FLAME tag is not supposed to be received from upper layers");

        }

      FlameRtable::LookupResult result = m_rtable->Lookup (destination);

      if (result.retransmitter == Mac48Address::GetBroadcast ())

        {

          m_lastBroadcast = Simulator::Now ();

        }

      if (m_lastBroadcast + m_broadcastInterval < Simulator::Now ())

        {

          result.retransmitter = Mac48Address::GetBroadcast ();

          result.ifIndex = FlameRtable::INTERFACE_ANY;

          m_lastBroadcast = Simulator::Now ();

        }

      FlameHeader flameHdr;

      flameHdr.AddCost (0);

      flameHdr.SetSeqno (m_myLastSeqno++);

      flameHdr.SetProtocol (protocolType);

      flameHdr.SetOrigDst (destination);

      flameHdr.SetOrigSrc (source);

      m_stats.txBytes += packet->GetSize ();

      packet->AddHeader (flameHdr);

      tag.receiver = result.retransmitter;

      if (result.retransmitter == Mac48Address::GetBroadcast ())

        {

          m_stats.txBroadcast++;

        }

      else

        {

          m_stats.txUnicast++;

        }

      NS_LOG_DEBUG ("Source: send packet with RA = " << tag.receiver);

      packet->AddPacketTag (tag);

      routeReply (true, packet, source, destination, FLAME_PROTOCOL, result.ifIndex);

    }

  else

    {

      FlameHeader flameHdr;

      packet->RemoveHeader (flameHdr);

      FlameTag tag;

      if (!packet->RemovePacketTag (tag))

        {

          NS_FATAL_ERROR ("FLAME tag must exust here");

        }

      if (source == GetAddress ())

        {

          if (tag.receiver != Mac48Address::GetBroadcast ())

            {

              NS_LOG_DEBUG ("received packet with SA = GetAddress (), RA = " << tag.receiver << ", TA = "

                  << tag.transmitter << ", I am " << GetAddress ());

            }

          m_stats.totalDropped++;

          return false;

        }

      if (destination == Mac48Address::GetBroadcast ())

        {

          //Broadcast always is forwarded as broadcast!

          NS_ASSERT (HandleDataFrame (flameHdr.GetSeqno (), source, flameHdr, tag.transmitter, sourceIface));

          FlameTag tag (Mac48Address::GetBroadcast ());

          flameHdr.AddCost (1);

          m_stats.txBytes += packet->GetSize ();

          packet->AddHeader (flameHdr);

          packet->AddPacketTag (tag);

          routeReply (true, packet, source, destination, FLAME_PROTOCOL, FlameRtable::INTERFACE_ANY);

          m_stats.txBroadcast++;

          return true;

        }

      else

        {

          if (HandleDataFrame (flameHdr.GetSeqno (), source, flameHdr, tag.transmitter, sourceIface))

            {

              return false;

            }

          FlameRtable::LookupResult result = m_rtable->Lookup (destination);

          if (tag.receiver != Mac48Address::GetBroadcast ())

            {

              if (result.retransmitter == Mac48Address::GetBroadcast ())

                {

                  NS_LOG_DEBUG ("unicast packet dropped, because no route! I am " << GetAddress ()

                      << ", RA = " << tag.receiver << ", TA = " << tag.transmitter);

                  m_stats.totalDropped++;

                  return false;

                }

            }

          tag.receiver = result.retransmitter;

          if (result.retransmitter == Mac48Address::GetBroadcast ())

            {

              m_stats.txBroadcast++;

            }

          else

            {

              m_stats.txUnicast++;

            }

          m_stats.txBytes += packet->GetSize ();

          flameHdr.AddCost (1);

          packet->AddHeader (flameHdr);

          packet->AddPacketTag (tag);

          routeReply (true, packet, source, destination, FLAME_PROTOCOL, result.ifIndex);

          return true;

        }

      return true;

    }

  return false;

}

bool

FlameProtocol::RemoveRoutingStuff (uint32_t fromIface, const Mac48Address source,

    const Mac48Address destination, Ptr<Packet> packet, uint16_t& protocolType)

{

  //Filter seqno:

  if (source == GetAddress ())

    {

      NS_LOG_DEBUG ("Dropped my own frame!");

      return false;

    }

  FlameTag tag;

  if (!packet->RemovePacketTag (tag))

    {

      NS_FATAL_ERROR ("FLAME tag must exist when packet is coming to protocol");

    }

  //TODO: send path update

  FlameHeader flameHdr;

  packet->RemoveHeader (flameHdr);

  NS_ASSERT (protocolType == FLAME_PROTOCOL);

  protocolType = flameHdr.GetProtocol ();

  return (!HandleDataFrame (flameHdr.GetSeqno (), source, flameHdr, tag.transmitter, fromIface));

}

bool

FlameProtocol::Install (Ptr<MeshPointDevice> mp)

{

  m_mp = mp;

  std::vector<Ptr<NetDevice> > interfaces = mp->GetInterfaces ();

  for (std::vector<Ptr<NetDevice> >::const_iterator i = interfaces.begin (); i != interfaces.end (); i++)

    {

      // Checking for compatible net device

      Ptr<WifiNetDevice> wifiNetDev = (*i)->GetObject<WifiNetDevice> ();

      if (wifiNetDev == 0)

        {

          return false;

        }

      Ptr<MeshWifiInterfaceMac> mac = wifiNetDev->GetMac ()->GetObject<MeshWifiInterfaceMac> ();

      if (mac == 0)

        {

          return false;

        }

      // Installing plugins:

      Ptr<FlameProtocolMac> flameMac = Create<FlameProtocolMac> (wifiNetDev->GetIfIndex (), this);

      m_interfaces[wifiNetDev->GetIfIndex ()] = flameMac;

      mac->SetBeaconGeneration (false);

      mac->InstallPlugin (flameMac);

    }

  mp->SetRoutingProtocol (this);

  // Mesh point aggregates all installed protocols

  mp->AggregateObject (this);

  m_address = Mac48Address::ConvertFrom (mp->GetAddress ());//* address;

  return true;

}

Mac48Address

FlameProtocol::GetAddress ()

{

  return m_address;

}

bool

FlameProtocol::HandleDataFrame (uint16_t seqno, Mac48Address source, const FlameHeader flameHdr,

    Mac48Address receiver, uint32_t fromInterface)

{

  if (source == GetAddress ())

    {

      return true;

    }

  FlameRtable::LookupResult result = m_rtable->Lookup (source);

  if (result.retransmitter == Mac48Address::GetBroadcast ())

    {

      m_rtable->AddPath (source, receiver, fromInterface, flameHdr.GetCost (), flameHdr.GetSeqno ());

      return false;

    }

  if (result.seqnum >= seqno)

    {

      return true;

    }

  if (flameHdr.GetCost () > m_maxCost)

    {

      m_stats.droppedTtl++;

      return true;

    }

  m_rtable->AddPath (source, receiver, fromInterface, flameHdr.GetCost (), flameHdr.GetSeqno ());

  return false;

}

//Statistics:

FlameProtocol::Statistics::Statistics () :

  txUnicast (0), txBroadcast (0), txBytes (0), droppedTtl (0), totalDropped (0)

{

}

void

FlameProtocol::Statistics::Print (std::ostream & os) const

{

  os << "<Statistics "

    "txUnicast=\"" << txUnicast << "\" "

    "txBroadcast=\"" << txBroadcast << "\" "

    "txBytes=\"" << txBytes << "\" "

    "droppedTtl=\"" << droppedTtl << "\" "

    "totalDropped=\"" << totalDropped << "\"/>\n";

}

void

FlameProtocol::Report (std::ostream & os) const

{

  os << "<Flame "

    "address=\"" << m_address << "\"\n"

    "broadcastInterval=\"" << m_broadcastInterval.GetSeconds () << "\"\n"

    "maxCost=\"" << (uint16_t) m_maxCost << "\">\n";

  m_stats.Print (os);

  for (FlamePluginMap::const_iterator plugin = m_interfaces.begin (); plugin != m_interfaces.end (); plugin++)

    {

      plugin->second->Report (os);

    }

  os << "</Flame>\n";

}

void

FlameProtocol::ResetStats ()

{

  m_stats = Statistics ();

  for (FlamePluginMap::const_iterator plugin = m_interfaces.begin (); plugin != m_interfaces.end (); plugin++)

    {

      plugin->second->ResetStats ();

    }

}

} //namespace flame

} //namespace ns3