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

/*

 * Copyright (c) 2008 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 "wifi-mac.h"

#include "ns3/uinteger.h"

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (WifiMac);

Time

WifiMac::GetDefaultMaxPropagationDelay (void)

{

  // 1000m 

  return Seconds (1000.0 / 300000000.0);

}

Time

WifiMac::GetDefaultSlot (void)

{

  // 802.11-a specific

  return MicroSeconds (9);

}

Time

WifiMac::GetDefaultSifs (void)

{

  // 802.11-a specific

  return MicroSeconds (16);

}

Time

WifiMac::GetDefaultEifsNoDifs (void)

{

  return GetDefaultSifs () + GetDefaultCtsAckDelay ();

}

Time

WifiMac::GetDefaultCtsAckDelay (void)

{

  // 802.11-a specific: 6mb/s

  return MicroSeconds (44);

}

Time

WifiMac::GetDefaultCtsAckTimeout (void)

{

  /* Cts_Timeout and Ack_Timeout are specified in the Annex C 

     (Formal description of MAC operation, see details on the 

     Trsp timer setting at page 346)

  */

  Time ctsTimeout = GetDefaultSifs ();

  ctsTimeout += GetDefaultCtsAckDelay ();

  ctsTimeout += GetDefaultMaxPropagationDelay () * Scalar (2);

  ctsTimeout += GetDefaultSlot ();

  return ctsTimeout;

}

TypeId 

WifiMac::GetTypeId (void)

{

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

    .SetParent<Object> ()

    .AddAttribute ("CtsTimeout", "When this timeout expires, the RTS/CTS handshake has failed.",

                   TimeValue (GetDefaultCtsAckTimeout ()),

                   MakeTimeAccessor (&WifiMac::m_ctsTimeout),

                   MakeTimeChecker ())

    .AddAttribute ("AckTimeout", "When this timeout expires, the DATA/ACK handshake has failed.",

                   TimeValue (GetDefaultCtsAckTimeout ()),

                   MakeTimeAccessor (&WifiMac::GetAckTimeout,

                                     &WifiMac::SetAckTimeout),

                   MakeTimeChecker ())

    .AddAttribute ("Sifs", "The value of the SIFS constant.",

                   TimeValue (GetDefaultSifs ()),

                   MakeTimeAccessor (&WifiMac::SetSifs,

				     &WifiMac::GetSifs),

                   MakeTimeChecker ())

    .AddAttribute ("EifsNoDifs", "The value of EIFS-DIFS",

		   TimeValue (GetDefaultEifsNoDifs ()),

		   MakeTimeAccessor (&WifiMac::SetEifsNoDifs,

				     &WifiMac::GetEifsNoDifs),

		   MakeTimeChecker ())

    .AddAttribute ("Slot", "The duration of a Slot.",

                   TimeValue (GetDefaultSlot ()),

                   MakeTimeAccessor (&WifiMac::SetSlot,

				     &WifiMac::GetSlot),

                   MakeTimeChecker ())

    .AddAttribute ("Pifs", "The value of the PIFS constant.",

                   TimeValue (GetDefaultSifs () + GetDefaultSlot ()),

                   MakeTimeChecker ())

    .AddAttribute ("MaxPropagationDelay", "The maximum propagation delay. Unused for now.",

                   TimeValue (GetDefaultMaxPropagationDelay ()),

                   MakeTimeAccessor (&WifiMac::m_maxPropagationDelay),

                   MakeTimeChecker ())

    .AddAttribute ("MaxMsduSize", "The maximum size of an MSDU accepted by the MAC layer."

                   "This value conforms to the specification.",

		   UintegerValue (2304),

		   MakeUintegerAccessor (&WifiMac::m_maxMsduSize),

		   MakeUintegerChecker<uint16_t> (1,2304))

    .AddAttribute ("Ssid", "The ssid we want to belong to.",

		   SsidValue (Ssid ("default")),

		   MakeSsidAccessor (&WifiMac::GetSsid,

				     &WifiMac::SetSsid),

		   MakeSsidChecker ())

    ;

  return tid;

}

void

WifiMac::SetPifs (Time pifs)

{

  m_pifs = pifs;

}

void 

WifiMac::SetCtsTimeout (Time ctsTimeout)

{

  m_ctsTimeout = ctsTimeout;

}

void 

WifiMac::SetMaxPropagationDelay (Time delay)

{

  m_maxPropagationDelay = delay;

}

Time

WifiMac::GetPifs (void) const

{

  return m_pifs;

}

Time

WifiMac::GetCtsTimeout (void) const

{

  return m_ctsTimeout;

}

Time

WifiMac::GetMsduLifetime (void) const

{

  return Seconds (10);

}

Time

WifiMac::GetMaxPropagationDelay (void) const

{

  return m_maxPropagationDelay;

}

uint32_t 

WifiMac::GetMaxMsduSize (void) const

{

  return m_maxMsduSize;

}

} // namespace ns3