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

/*

 * Copyright (c) 2006,2007 INRIA

 *

 * 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/packet.h"

#include "ns3/simulator.h"

#include "ns3/log.h"

#include "ns3/pointer.h"

#include "ns3/net-device.h"

#include "ns3/node.h"

#include "ns3/propagation-loss-model.h"

#include "ns3/propagation-delay-model.h"

#include "ns3/mobility-model.h"

#include "yans-wifi-channel.h"

#include "yans-wifi-phy.h"

#include "wifi-utils.h"

namespace ns3 {

NS_LOG_COMPONENT_DEFINE ("YansWifiChannel");

NS_OBJECT_ENSURE_REGISTERED (YansWifiChannel);

TypeId

YansWifiChannel::GetTypeId (void)

{

  static TypeId tid = TypeId ("ns3::YansWifiChannel")

    .SetParent<Channel> ()

    .SetGroupName ("Wifi")

    .AddConstructor<YansWifiChannel> ()

    .AddAttribute ("PropagationLossModel", "A pointer to the propagation loss model attached to this channel.",

                   PointerValue (),

                   MakePointerAccessor (&YansWifiChannel::m_loss),

                   MakePointerChecker<PropagationLossModel> ())

    .AddAttribute ("PropagationDelayModel", "A pointer to the propagation delay model attached to this channel.",

                   PointerValue (),

                   MakePointerAccessor (&YansWifiChannel::m_delay),

                   MakePointerChecker<PropagationDelayModel> ())

  ;

  return tid;

}

YansWifiChannel::YansWifiChannel ()

{

  NS_LOG_FUNCTION (this);

}

YansWifiChannel::~YansWifiChannel ()

{

  NS_LOG_FUNCTION (this);

  m_phyList.clear ();

}

void

YansWifiChannel::SetPropagationLossModel (const Ptr<PropagationLossModel> loss)

{

  NS_LOG_FUNCTION (this << loss);

  m_loss = loss;

}

void

YansWifiChannel::SetPropagationDelayModel (const Ptr<PropagationDelayModel> delay)

{

  NS_LOG_FUNCTION (this << delay);

  m_delay = delay;

}

void

YansWifiChannel::Send (Ptr<YansWifiPhy> sender, Ptr<const Packet> packet, double txPowerDbm, Time duration) const

{

  NS_LOG_FUNCTION (this << sender << packet << txPowerDbm << duration.GetSeconds ());

  Ptr<MobilityModel> senderMobility = sender->GetMobility ();

  NS_ASSERT (senderMobility != 0);

  for (PhyList::const_iterator i = m_phyList.begin (); i != m_phyList.end (); i++)

    {

      if (sender != (*i))

        {

          //For now don't account for inter channel interference nor channel bonding

          if ((*i)->GetChannelNumber () != sender->GetChannelNumber ())

            {

              continue;

            }

          Ptr<MobilityModel> receiverMobility = (*i)->GetMobility ()->GetObject<MobilityModel> ();

          Time delay = m_delay->GetDelay (senderMobility, receiverMobility);

          double rxPowerDbm = m_loss->CalcRxPower (txPowerDbm, senderMobility, receiverMobility);

          NS_LOG_DEBUG ("propagation: txPower=" << txPowerDbm << "dbm, rxPower=" << rxPowerDbm << "dbm, " <<

                        "distance=" << senderMobility->GetDistanceFrom (receiverMobility) << "m, delay=" << delay);

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

          Ptr<NetDevice> dstNetDevice = (*i)->GetDevice ();

          uint32_t dstNode;

          if (dstNetDevice == 0)

            {

              dstNode = 0xffffffff;

            }

          else

            {

              dstNode = dstNetDevice->GetNode ()->GetId ();

            }

          Simulator::ScheduleWithContext (dstNode,

                                          delay, &YansWifiChannel::Receive,

                                          (*i), copy, rxPowerDbm, duration);

        }

    }

}

void

YansWifiChannel::Receive (Ptr<YansWifiPhy> phy, Ptr<Packet> packet, double rxPowerDbm, Time duration)

{

  NS_LOG_FUNCTION (phy << packet << rxPowerDbm << duration.GetSeconds ());

  phy->StartReceivePreambleAndHeader (packet, DbmToW (rxPowerDbm + phy->GetRxGain ()), duration);

}

std::size_t

YansWifiChannel::GetNDevices (void) const

{

  return m_phyList.size ();

}

Ptr<NetDevice>

YansWifiChannel::GetDevice (std::size_t i) const

{

  return m_phyList[i]->GetDevice ()->GetObject<NetDevice> ();

}

void

YansWifiChannel::Add (Ptr<YansWifiPhy> phy)

{

  NS_LOG_FUNCTION (this << phy);

  m_phyList.push_back (phy);

}

int64_t

YansWifiChannel::AssignStreams (int64_t stream)

{

  NS_LOG_FUNCTION (this << stream);

  int64_t currentStream = stream;

  currentStream += m_loss->AssignStreams (stream);

  return (currentStream - stream);

}

} //namespace ns3