/* -*- 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

 *

 * Authors: Kirill Andreev <andreev@iitp.ru>

 *          Pavel Boyko <boyko@iitp.ru>

 */

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

#include "ns3/mesh-wifi-beacon.h"

#include "ns3/log.h"

#include "ns3/wifi-phy.h"

#include "ns3/dcf-manager.h"

#include "ns3/mac-rx-middle.h"

#include "ns3/mac-low.h"

#include "ns3/dca-txop.h"

#include "ns3/random-variable.h"

#include "ns3/simulator.h"

#include "ns3/yans-wifi-phy.h"

#include "ns3/pointer.h"

#include "ns3/qos-tag.h"

NS_LOG_COMPONENT_DEFINE ("MeshWifiInterfaceMac");

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (MeshWifiInterfaceMac);

TypeId

MeshWifiInterfaceMac::GetTypeId ()

{

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

    .SetParent<WifiMac> ()

    .AddConstructor<MeshWifiInterfaceMac> ()

    .AddAttribute ("BeaconInterval", "Beacon Interval",

        TimeValue (Seconds (0.5)),

        MakeTimeAccessor (&MeshWifiInterfaceMac::m_beaconInterval),

        MakeTimeChecker ()

        )

    .AddAttribute ("RandomStart", "Window when beacon generating starts (uniform random) in seconds",

        TimeValue (Seconds (0.5)),

        MakeTimeAccessor (&MeshWifiInterfaceMac::m_randomStart),

        MakeTimeChecker ()

        )

    .AddAttribute ("BeaconGeneration", "Enable/Disable Beaconing.",

        BooleanValue (true),

        MakeBooleanAccessor (

          &MeshWifiInterfaceMac::SetBeaconGeneration,

          &MeshWifiInterfaceMac::GetBeaconGeneration

          ),

        MakeBooleanChecker ()

        );

  return tid;

}

MeshWifiInterfaceMac::MeshWifiInterfaceMac ()

{

  NS_LOG_FUNCTION (this);

  m_rxMiddle = new MacRxMiddle ();

  m_rxMiddle->SetForwardCallback (MakeCallback (&MeshWifiInterfaceMac::Receive, this));

  m_low = CreateObject<MacLow> ();

  m_low->SetRxCallback (MakeCallback (&MacRxMiddle::Receive, m_rxMiddle));

  m_dcfManager = new DcfManager ();

  m_dcfManager->SetupLowListener (m_low);

  m_beaconDca = CreateObject<DcaTxop> ();

  m_beaconDca->SetLow (m_low);

  m_beaconDca->SetMinCw (0);

  m_beaconDca->SetMaxCw (0);

  m_beaconDca->SetAifsn (1);

  m_beaconDca->SetManager (m_dcfManager);

}

MeshWifiInterfaceMac::~MeshWifiInterfaceMac ()

{

  NS_LOG_FUNCTION (this);

}

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

// WifiMac inherited

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

void

MeshWifiInterfaceMac::SetSlot (Time slotTime)

{

  NS_LOG_FUNCTION (this << slotTime);

  m_dcfManager->SetSlot (slotTime);

  m_low->SetSlotTime (slotTime);

  m_slot = slotTime;

}

void

MeshWifiInterfaceMac::SetSifs (Time sifs)

{

  NS_LOG_FUNCTION (this << sifs);

  m_dcfManager->SetSifs (sifs);

  m_low->SetSifs (sifs);

  m_sifs = sifs;

}

void

MeshWifiInterfaceMac::SetAckTimeout (Time ackTimeout)

{

  m_low->SetAckTimeout (ackTimeout);

}

void

MeshWifiInterfaceMac::SetCtsTimeout (Time ctsTimeout)

{

  m_low->SetCtsTimeout (ctsTimeout);

}

void

MeshWifiInterfaceMac::SetPifs (Time pifs)

{

  NS_LOG_FUNCTION (this << pifs);

  m_pifs = pifs;

}

void

MeshWifiInterfaceMac::SetEifsNoDifs (Time eifsNoDifs)

{

  NS_LOG_FUNCTION (this << eifsNoDifs);

  m_dcfManager->SetEifsNoDifs (eifsNoDifs);

  m_eifsNoDifs = eifsNoDifs;

}

Time

MeshWifiInterfaceMac::GetSlot () const

{

  return m_slot;

}

Time

MeshWifiInterfaceMac::GetSifs () const

{

  return m_sifs;

}

Time

MeshWifiInterfaceMac::GetEifsNoDifs () const

{

  return m_eifsNoDifs;

}

Time

MeshWifiInterfaceMac::GetAckTimeout () const

{

  return m_low->GetAckTimeout ();

}

Time

MeshWifiInterfaceMac::GetCtsTimeout () const

{

  return m_low->GetCtsTimeout ();

}

Time

MeshWifiInterfaceMac::GetPifs () const

{

  return m_low->GetPifs ();

}

void

MeshWifiInterfaceMac::SetWifiPhy (Ptr<WifiPhy> phy)

{

  NS_LOG_FUNCTION (this << phy);

  m_phy = phy;

  m_dcfManager->SetupPhyListener (phy);

  m_low->SetPhy (phy);

}

void

MeshWifiInterfaceMac::SetWifiRemoteStationManager (Ptr<WifiRemoteStationManager> stationManager)

{

  NS_LOG_FUNCTION (this << stationManager);

  m_stationManager = stationManager;

  for (Queues::const_iterator i = m_queues.begin (); i != m_queues.end (); i ++)

  {

    i->second->SetWifiRemoteStationManager (stationManager);

  }

  m_beaconDca->SetWifiRemoteStationManager (stationManager);

  m_low->SetWifiRemoteStationManager (stationManager);

}

void

MeshWifiInterfaceMac::Enqueue (Ptr<const Packet> packet, Mac48Address to, Mac48Address from)

{

  NS_LOG_FUNCTION (this << packet << to << from);

  ForwardDown (packet, from, to);

}

void

MeshWifiInterfaceMac::Enqueue (Ptr<const Packet> packet, Mac48Address to)

{

  NS_LOG_FUNCTION (this << packet << to);

  ForwardDown (packet, m_low->GetAddress (), to);

}

bool

MeshWifiInterfaceMac::SupportsSendFrom () const

{

  return true;

}

void

MeshWifiInterfaceMac::SetForwardUpCallback (Callback<void,Ptr<Packet>, Mac48Address, Mac48Address> upCallback)

{

  NS_LOG_FUNCTION (this);

  m_upCallback = upCallback;

}

void

MeshWifiInterfaceMac::SetLinkUpCallback (Callback<void> linkUp)

{

  NS_LOG_FUNCTION (this);

  if (!linkUp.IsNull ())

    {

      linkUp ();

    }

}

void

MeshWifiInterfaceMac::SetLinkDownCallback (Callback<void> linkDown)

{

  NS_LOG_FUNCTION (this);

}

Mac48Address

MeshWifiInterfaceMac::GetAddress () const

{

  return m_address;

}

Mac48Address

MeshWifiInterfaceMac::GetBssid () const

{

  return m_address;

}

Ssid

MeshWifiInterfaceMac::GetSsid () const

{

  return m_meshId;

}

void

MeshWifiInterfaceMac::SetAddress (Mac48Address address)

{

  NS_LOG_FUNCTION (address);

  m_low->SetAddress (address);

  m_address = address;

}

void

MeshWifiInterfaceMac::SetSsid (Ssid ssid)

{

  NS_LOG_FUNCTION (ssid);

  m_meshId = ssid;

}

void

MeshWifiInterfaceMac::DoDispose ()

{

  NS_LOG_FUNCTION (this);

  delete m_rxMiddle;

  delete m_dcfManager;

  //Delete smart pointers:

  m_rxMiddle = 0;

  m_low = 0;

  m_dcfManager = 0;

  m_phy = 0;

  m_queues.clear ();

  m_beaconSendEvent.Cancel ();

  m_beaconDca = 0;

  WifiMac::DoDispose ();

}

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

// Plugins

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

void

MeshWifiInterfaceMac::InstallPlugin ( Ptr<MeshWifiInterfaceMacPlugin> plugin)

{

  NS_LOG_FUNCTION (this);

  plugin->SetParent (this);

  m_plugins.push_back (plugin);

}

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

// Switch channels

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

uint16_t MeshWifiInterfaceMac::GetFrequencyChannel () const

{

  NS_LOG_FUNCTION (this);

  NS_ASSERT (m_phy != 0); // need PHY to set/get channel

  Ptr<YansWifiPhy> phy = m_phy->GetObject<YansWifiPhy> ();

  if (phy != 0)

    {

      return phy->GetChannelNumber ();

    }

  else

    {

      return 0;

    }

}

void MeshWifiInterfaceMac::SwitchFrequencyChannel (uint16_t new_id)

{

  NS_LOG_FUNCTION (this);

  NS_ASSERT (m_phy != 0); // need PHY to set/get channel

  /* TODO

   *

   * Correct channel switching is:

   *

   * 1. Interface down, e.g. to stop packets from layer 3

   * 2. Wait before all output queues will be empty

   * 3. Switch PHY channel

   * 4. Interface up

   *

   * Now we use dirty channel switch -- just change frequency

   */

  Ptr<YansWifiPhy> phy = m_phy->GetObject<YansWifiPhy> ();

  phy->SetChannelNumber (new_id);

  // Don't know NAV on new channel

  m_dcfManager->NotifyNavResetNow (Seconds (0));

}

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

// Forward frame up/down

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

void

MeshWifiInterfaceMac::ForwardUp (Ptr<Packet> packet, Mac48Address src, Mac48Address dst)

{

  NS_LOG_FUNCTION (this << packet << src);

  m_upCallback (packet, src, dst);

}

void

MeshWifiInterfaceMac::ForwardDown (Ptr<const Packet> const_packet, Mac48Address from, Mac48Address to)

{

  // copy packet to allow modifications

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

  WifiMacHeader hdr;

  hdr.SetTypeData ();

  hdr.SetAddr2 (GetAddress ());

  hdr.SetAddr3 (to);

  hdr.SetAddr4 (from);

  hdr.SetDsFrom ();

  hdr.SetDsTo ();

  // Fill QoS fields:

  hdr.SetQosAckPolicy (WifiMacHeader::NORMAL_ACK);

  hdr.SetQosNoEosp ();

  hdr.SetQosNoAmsdu ();

  hdr.SetQosTxopLimit (0);

  // Address 1 is unknwon here. Routing plugin is responsible to correctly set it.

  hdr.SetAddr1 (Mac48Address ());

  // Filter packet through all installed plugins

  for (PluginList::const_iterator i = m_plugins.end()-1; i != m_plugins.begin()-1; i--)

    {

      bool drop = ! ((*i)->UpdateOutcomingFrame(packet, hdr, from, to));

      if (drop)

        {

          return; // plugin drops frame

        }

    }

  // Assert that address1 is set. Assert will fail e.g. if there is no installed routing plugin.

  NS_ASSERT (hdr.GetAddr1() != Mac48Address() );

  // Queue frame

  WifiRemoteStation *destination = m_stationManager->Lookup (to);

  if (destination->IsBrandNew ())

    {

      // in adhoc mode, we assume that every destination

      // supports all the rates we support.

      for (uint32_t i = 0; i < m_phy->GetNModes (); i++)

        {

          destination->AddSupportedMode (m_phy->GetMode (i));

        }

      destination->RecordDisassociated ();

    }

  //Classify: application sets a tag, which is removed here

  // Get Qos tag:

  AccessClass ac = AC_BE;

  QosTag tag;

  if (packet->RemovePacketTag (tag))

    {

      ac = QosUtilsMapTidToAc (tag.Get ());

    }

  m_stats.sentFrames ++;

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

  NS_ASSERT(m_queues.find(ac) != m_queues.end ());

  m_queues[ac]->Queue (packet, hdr);

}

void

MeshWifiInterfaceMac::SendManagementFrame (Ptr<Packet> packet, const WifiMacHeader& hdr)

{

  //Filter management frames:

  WifiMacHeader header = hdr;

  for (PluginList::const_iterator i = m_plugins.end()-1; i != m_plugins.begin()-1; i--)

    {

      bool drop = ! ((*i)->UpdateOutcomingFrame(packet, header, Mac48Address (), Mac48Address ()));

      if (drop)

        {

          return; // plugin drops frame

        }

    }

  m_stats.sentFrames ++;

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

  Queues::iterator i = m_queues.find (AC_VO);

  if (i == m_queues.end ())

  {

    NS_FATAL_ERROR("Voice queue is not set up!");

  }

  m_queues[AC_VO]->Queue (packet, header);

}

SupportedRates

MeshWifiInterfaceMac::GetSupportedRates () const

{

  // set the set of supported rates and make sure that we indicate

  // the Basic Rate set in this set of supported rates.

  SupportedRates rates;

  for (uint32_t i = 0; i < m_phy->GetNModes (); i++)

    {

      WifiMode mode = m_phy->GetMode (i);

      rates.AddSupportedRate (mode.GetDataRate ());

    }

  // set the basic rates

  for (uint32_t j = 0; j < m_stationManager->GetNBasicModes (); j++)

    {

      WifiMode mode = m_stationManager->GetBasicMode (j);

      rates.SetBasicRate (mode.GetDataRate ());

    }

  return rates;

}

bool

MeshWifiInterfaceMac::CheckSupportedRates(SupportedRates rates) const

{

  for (uint32_t i = 0; i < m_stationManager->GetNBasicModes (); i++)

  {

    WifiMode mode = m_stationManager->GetBasicMode (i);

    if (!rates.IsSupportedRate (mode.GetDataRate ()))

      {

        return false;

      }

  }

  return true;

}

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

// Beacons

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

void 

MeshWifiInterfaceMac::SetRandomStartDelay (Time interval)

{

  NS_LOG_FUNCTION (this << interval);

  m_randomStart = interval;

}

void

MeshWifiInterfaceMac::SetBeaconInterval (Time interval)

{

  NS_LOG_FUNCTION (this << interval);

  m_beaconInterval = interval;

}

Time

MeshWifiInterfaceMac::GetBeaconInterval () const

{

  return m_beaconInterval;

}

void

MeshWifiInterfaceMac::SetBeaconGeneration (bool enable)

{

  NS_LOG_FUNCTION (this << enable);

  if (enable)

    {

      // Now start sending beacons after some random delay (to avoid collisions)

      UniformVariable coefficient (0.0, m_randomStart.GetSeconds());

      Time randomStart = Seconds (coefficient.GetValue());

      m_beaconSendEvent = Simulator::Schedule (randomStart, &MeshWifiInterfaceMac::SendBeacon, this);

      m_tbtt = Simulator::Now() + randomStart;