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

/*

 * Copyright (c) 2005,2006 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/assert.h"

#include "ns3/log.h"

#include "ns3/simulator.h"

#include "ns3/node.h"

#include "nqap-wifi-mac.h"

#include "dca-txop.h"

#include "wifi-mac-header.h"

#include "mgt-headers.h"

#include "wifi-phy.h"

#include "dcf-manager.h"

#include "mac-rx-middle.h"

#include "mac-low.h"

NS_LOG_COMPONENT_DEFINE ("NqapWifiMac");

#define TRACE(x) \

  NS_LOG_DEBUG(Simulator::Now () << " " << GetAddress () << " " << x);

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (NqapWifiMac);

TypeId 

NqapWifiMac::GetTypeId (void)

{

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

    .SetParent<WifiMac> ()

    .AddConstructor<NqapWifiMac> ()

    .AddAttribute ("BeaconInterval", "Delay between two beacons",

                   Seconds (1.0),

                   MakeTimeAccessor (&NqapWifiMac::m_beaconInterval),

                   MakeTimeChecker ())

    .AddAttribute ("BeaconGeneration", "Whether or not beacons are generated.",

                   Boolean (false),

                   MakeBooleanAccessor (&NqapWifiMac::SetBeaconGeneration,

                                        &NqapWifiMac::GetBeaconGeneration),

                   MakeBooleanChecker ())

    ;

  return tid;

}

NqapWifiMac::NqapWifiMac ()

{

  m_rxMiddle = new MacRxMiddle ();

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

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

  m_low->SetMac (this);

  m_dcfManager = new DcfManager ();

  m_dcfManager->SetupLowListener (m_low);

  m_dca = CreateObject<DcaTxop> ();

  m_dca->SetLow (m_low);

  m_dca->SetManager (m_dcfManager);

  m_dca->SetTxOkCallback (MakeCallback (&NqapWifiMac::TxOk, this));

  m_dca->SetTxFailedCallback (MakeCallback (&NqapWifiMac::TxFailed, this));

  m_beaconDca = CreateObject<DcaTxop> ();

  m_beaconDca->SetLow (m_low);

  m_beaconDca->SetManager (m_dcfManager);

}

NqapWifiMac::~NqapWifiMac ()

{}

void

NqapWifiMac::DoDispose (void)

{

  delete m_rxMiddle;

  delete m_dcfManager;

  m_rxMiddle = 0;

  m_low = 0;

  m_dcfManager = 0;

  m_phy = 0;

  m_dca = 0;

  m_beaconDca = 0;

  m_beaconEvent.Cancel ();

  WifiMac::DoDispose ();

}

void

NqapWifiMac::SetBeaconGeneration (bool enable)

{

  if (enable)

    {

      m_beaconEvent = Simulator::ScheduleNow (&NqapWifiMac::SendOneBeacon, this);

    }

  else

    {

      m_beaconEvent.Cancel ();

    }

}

bool

NqapWifiMac::GetBeaconGeneration (void) const

{

  return m_beaconEvent.IsRunning ();

}

void 

NqapWifiMac::SetSlot (Time slotTime)

{

  m_dcfManager->SetSlot (slotTime);

  WifiMac::SetSlot (slotTime);

}

void 

NqapWifiMac::SetSifs (Time sifs)

{

  m_dcfManager->SetSifs (sifs);

  WifiMac::SetSifs (sifs);

}

void 

NqapWifiMac::SetEifsNoDifs (Time eifsNoDifs)

{

  m_dcfManager->SetEifsNoDifs (eifsNoDifs);

  WifiMac::SetEifsNoDifs (eifsNoDifs);

}

void 

NqapWifiMac::SetWifiPhy (Ptr<WifiPhy> phy)

{

  m_phy = phy;

  m_dcfManager->SetupPhyListener (phy);

  m_low->SetPhy (phy);

}

void 

NqapWifiMac::SetWifiRemoteStationManager (Ptr<WifiRemoteStationManager> stationManager)

{

  m_stationManager = stationManager;

  m_dca->SetWifiRemoteStationManager (stationManager);

  m_beaconDca->SetWifiRemoteStationManager (stationManager);

  m_low->SetWifiRemoteStationManager (stationManager);

}

void 

NqapWifiMac::SetForwardUpCallback (Callback<void,Ptr<Packet>, const Mac48Address &> upCallback)

{

  m_upCallback = upCallback;

}

void 

NqapWifiMac::SetLinkUpCallback (Callback<void> linkUp)

{

  if (!linkUp.IsNull ())

    {

      linkUp ();

    }

}

void 

NqapWifiMac::SetLinkDownCallback (Callback<void> linkDown)

{}

Mac48Address 

NqapWifiMac::GetAddress (void) const

{

  return m_address;

}

Ssid 

NqapWifiMac::GetSsid (void) const

{

  return m_ssid;

}

Mac48Address 

NqapWifiMac::GetBssid (void) const

{

  return m_address;

}

void 

NqapWifiMac::SetAddress (Mac48Address address)

{

  m_address = address;

}

void 

NqapWifiMac::SetSsid (Ssid ssid)

{

  m_ssid = ssid;

}

void 

NqapWifiMac::SetBeaconInterval (Time interval)

{

  m_beaconInterval = interval;

}

void

NqapWifiMac::StartBeaconing (void)

{

  SendOneBeacon ();

}

void 

NqapWifiMac::ForwardUp (Ptr<Packet> packet, Mac48Address from)

{

  m_upCallback (packet, from);

}

void 

NqapWifiMac::ForwardDown (Ptr<const Packet> packet, Mac48Address from, Mac48Address to)

{

  WifiMacHeader hdr;

  hdr.SetTypeData ();

  hdr.SetAddr1 (to);

  hdr.SetAddr2 (GetAddress ());

  hdr.SetAddr3 (from);

  hdr.SetDsFrom ();

  hdr.SetDsNotTo ();

  m_dca->Queue (packet, hdr);  

}

void 

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

{

  ForwardDown (packet, GetAddress (), to);

}

SupportedRates

NqapWifiMac::GetSupportedRates (void) const

{

  // send 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;

}

void

NqapWifiMac::SendProbeResp (Mac48Address to)

{

  TRACE ("send probe response to="<<to);

  WifiMacHeader hdr;

  hdr.SetProbeResp ();

  hdr.SetAddr1 (to);

  hdr.SetAddr2 (GetAddress ());

  hdr.SetAddr3 (GetAddress ());

  hdr.SetDsNotFrom ();

  hdr.SetDsNotTo ();

  Ptr<Packet> packet = Create<Packet> ();

  MgtProbeResponseHeader probe;

  probe.SetSsid (GetSsid ());

  probe.SetSupportedRates (GetSupportedRates ());

  probe.SetBeaconIntervalUs (m_beaconInterval.GetMicroSeconds ());

  packet->AddHeader (probe);

  m_dca->Queue (packet, hdr);

}

void

NqapWifiMac::SendAssocResp (Mac48Address to, bool success)

{

  TRACE ("send assoc response to="<<to);

  WifiMacHeader hdr;

  hdr.SetAssocResp ();

  hdr.SetAddr1 (to);

  hdr.SetAddr2 (GetAddress ());

  hdr.SetAddr3 (GetAddress ());

  hdr.SetDsNotFrom ();

  hdr.SetDsNotTo ();

  Ptr<Packet> packet = Create<Packet> ();

  MgtAssocResponseHeader assoc;

  StatusCode code;

  if (success)

    {

      code.SetSuccess ();

    }

  else

    {

      code.SetFailure ();

    }

  assoc.SetSupportedRates (GetSupportedRates ());

  assoc.SetStatusCode (code);

  packet->AddHeader (assoc);

  m_dca->Queue (packet, hdr);

}

void

NqapWifiMac::SendOneBeacon (void)

{

  TRACE ("send beacon to="<<Mac48Address::GetBroadcast ());

  WifiMacHeader hdr;

  hdr.SetBeacon ();

  hdr.SetAddr1 (Mac48Address::GetBroadcast ());

  hdr.SetAddr2 (GetAddress ());

  hdr.SetAddr3 (GetAddress ());

  hdr.SetDsNotFrom ();

  hdr.SetDsNotTo ();

  Ptr<Packet> packet = Create<Packet> ();

  MgtBeaconHeader beacon;

  beacon.SetSsid (GetSsid ());

  beacon.SetSupportedRates (GetSupportedRates ());

  beacon.SetBeaconIntervalUs (m_beaconInterval.GetMicroSeconds ());

  packet->AddHeader (beacon);

  m_beaconDca->Queue (packet, hdr);

  m_beaconEvent = Simulator::Schedule (m_beaconInterval, &NqapWifiMac::SendOneBeacon, this);

}

void 

NqapWifiMac::TxOk (WifiMacHeader const &hdr)

{

  WifiRemoteStation *station = m_stationManager->Lookup (hdr.GetAddr1 ());

  if (hdr.IsAssocResp () && 

      station->IsWaitAssocTxOk ()) 

    {

      TRACE ("associated with sta="<<hdr.GetAddr1 ());

      station->RecordGotAssocTxOk ();

    }

}

void 

NqapWifiMac::TxFailed (WifiMacHeader const &hdr)

{

  WifiRemoteStation *station = m_stationManager->Lookup (hdr.GetAddr1 ());

  if (hdr.IsAssocResp () && 

      station->IsWaitAssocTxOk ()) 

    {

      TRACE ("assoc failed with sta="<<hdr.GetAddr1 ());

      station->RecordGotAssocTxFailed ();

    }

}

void 

NqapWifiMac::Receive (Ptr<Packet> packet, WifiMacHeader const *hdr)

{

  WifiRemoteStation *station = m_stationManager->Lookup (hdr->GetAddr2 ());

  if (hdr->IsData ()) 

    {

      if (!hdr->IsFromDs () && 

          hdr->IsToDs () &&

          hdr->GetAddr1 () == GetAddress () &&

          station->IsAssociated ()) 

        {

          if (hdr->GetAddr3 () == GetAddress ()) 

            {

              TRACE ("frame for me from="<<hdr->GetAddr2 ());

              ForwardUp (packet, hdr->GetAddr2 ());

            } 

          else 

            {

              TRACE ("forwarding frame from="<<hdr->GetAddr2 ()<<", to="<<hdr->GetAddr3 ());

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

              ForwardDown (packet,

                           hdr->GetAddr2 (), 

                           hdr->GetAddr3 ());

              ForwardUp (copy, hdr->GetAddr2 ());

            }

        } 

      else if (hdr->IsFromDs () &&

               hdr->IsToDs ()) 

        {

          // this is an AP-to-AP frame

          // we ignore for now.

        } 

      else 

        {

          // we can ignore these frames since 

          // they are not targeted at the AP

        }

    } 

  else if (hdr->IsMgt ()) 

    {

      if (hdr->IsProbeReq ()) 

        {

          NS_ASSERT (hdr->GetAddr1 ().IsBroadcast ());

          SendProbeResp (hdr->GetAddr2 ());

        } 

      else if (hdr->GetAddr1 () == GetAddress ()) 

        {

          if (hdr->IsAssocReq ()) 

            {

              // first, verify that the the station's supported

              // rate set is compatible with our Basic Rate set

              MgtAssocRequestHeader assocReq;

              packet->RemoveHeader (assocReq);

              SupportedRates rates = assocReq.GetSupportedRates ();

              bool problem = false;

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

                {

                  WifiMode mode = m_stationManager->GetBasicMode (i);

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

                    {

                      problem = true;

                      break;

                    }

                }

              if (problem)

                {

                  // one of the Basic Rate set mode is not

                  // supported by the station. So, we return an assoc

                  // response with an error status.

                  SendAssocResp (hdr->GetAddr2 (), false);

                }

              else

                {

                  // station supports all rates in Basic Rate Set.

                  // record all its supported modes in its associated WifiRemoteStation

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

                    {

                      WifiMode mode = m_phy->GetMode (j);

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

                        {

                          station->AddSupportedMode (mode);

                        }

                    }

                  station->RecordWaitAssocTxOk ();

                  // send assoc response with success status.

                  SendAssocResp (hdr->GetAddr2 (), true);

                }

            } 

          else if (hdr->IsDisassociation ()) 

            {

              station->RecordDisassociated ();

            } 

          else if (hdr->IsReassocReq ()) 

            {

              /* we don't support reassoc frames for now */

            } 

          else if (hdr->IsAuthentication () ||

                   hdr->IsDeauthentication ()) 

            {

              /*

               */

            } 

          else 

            {

              /* unknown mgt frame

               */

            }

        }

    } 

  else 

    {

    /* damn, what could this be ? a control frame ?

     * control frames should never reach the MacHigh so,

     * this is likely to be a bug. assert.

     */

      NS_ASSERT (false);

    }  

}

} // namespace ns3