/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2010 CTTC
 *
 * 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: Nicola Baldo <nbaldo@cttc.es>
 */

#include "ns3/log.h"
#include "ns3/queue.h"
#include "ns3/simulator.h"
#include "ns3/enum.h"
#include "ns3/boolean.h"
#include "ns3/uinteger.h"
#include "ns3/pointer.h"
#include "ns3/channel.h"
#include "ns3/trace-source-accessor.h"
#include "aloha-noack-mac-header.h"
#include "aloha-noack-net-device.h"
#include "ns3/llc-snap-header.h"

NS_LOG_COMPONENT_DEFINE ("AlohaNoackNetDevice");


namespace ns3 {


std::ostream& operator<< (std::ostream& os, AlohaNoackNetDevice::State state)
{
  switch (state)
    {
    case AlohaNoackNetDevice::IDLE:
      os << "IDLE" ;
      break;
    case AlohaNoackNetDevice::TX:
      os << "TX" ;
      break;
    case AlohaNoackNetDevice::RX:
      os << "RX" ;
      break;
    }
  return os;
}


NS_OBJECT_ENSURE_REGISTERED (AlohaNoackNetDevice);

TypeId
AlohaNoackNetDevice::GetTypeId (void)
{
  static TypeId tid = TypeId ("ns3::AlohaNoackNetDevice")
    .SetParent<NetDevice> ()
    .AddConstructor<AlohaNoackNetDevice> ()
    .AddAttribute ("Address",
                   "The MAC address of this device.",
                   Mac48AddressValue (Mac48Address ("12:34:56:78:90:12")),
                   MakeMac48AddressAccessor (&AlohaNoackNetDevice::m_address),
                   MakeMac48AddressChecker ())
    .AddAttribute ("Queue",
                   "packets being transmitted get queued here",
                   PointerValue (),
                   MakePointerAccessor (&AlohaNoackNetDevice::m_queue),
                   MakePointerChecker<Queue> ())
    .AddAttribute ("Mtu", "The Maximum Transmission Unit",
                   UintegerValue (1500),
                   MakeUintegerAccessor (&AlohaNoackNetDevice::SetMtu,
                                         &AlohaNoackNetDevice::GetMtu),
                   MakeUintegerChecker<uint16_t> (1,65535))
    .AddAttribute ("Phy", "The PHY layer attached to this device.",
                   PointerValue (),
                   MakePointerAccessor (&AlohaNoackNetDevice::GetPhy,
                                        &AlohaNoackNetDevice::SetPhy),
                   MakePointerChecker<Object> ())
    .AddTraceSource ("MacTx",
                     "Trace source indicating a packet has arrived for transmission by this device",
                     MakeTraceSourceAccessor (&AlohaNoackNetDevice::m_macTxTrace))
    .AddTraceSource ("MacTxDrop",
                     "Trace source indicating a packet has been dropped by the device before transmission",
                     MakeTraceSourceAccessor (&AlohaNoackNetDevice::m_macTxDropTrace))
    .AddTraceSource ("MacPromiscRx",
                     "A packet has been received by this device, has been passed up from the physical layer "
                     "and is being forwarded up the local protocol stack.  This is a promiscuous trace,",
                     MakeTraceSourceAccessor (&AlohaNoackNetDevice::m_macPromiscRxTrace))
    .AddTraceSource ("MacRx",
                     "A packet has been received by this device, has been passed up from the physical layer "
                     "and is being forwarded up the local protocol stack.  This is a non-promiscuous trace,",
                     MakeTraceSourceAccessor (&AlohaNoackNetDevice::m_macRxTrace))
  ;
  return tid;
}

AlohaNoackNetDevice::AlohaNoackNetDevice ()
  : m_state (IDLE)
{
  NS_LOG_FUNCTION (this);
}
  
AlohaNoackNetDevice::~AlohaNoackNetDevice ()
{
  NS_LOG_FUNCTION (this);
  m_queue = 0;
}

void
AlohaNoackNetDevice::DoDispose ()
{
  NS_LOG_FUNCTION (this);
  m_queue = 0;
  m_node = 0;
  m_channel = 0;
  m_currentPkt = 0;
  m_phy = 0;
  m_phyMacTxStartCallback = MakeNullCallback< bool, Ptr<Packet> > ();
  NetDevice::DoDispose ();
}


void
AlohaNoackNetDevice::SetIfIndex (const uint32_t index)
{
  NS_LOG_FUNCTION (index);
  m_ifIndex = index;
}

uint32_t
AlohaNoackNetDevice::GetIfIndex (void) const
{
  NS_LOG_FUNCTION (this);
  return m_ifIndex;
}

bool
AlohaNoackNetDevice::SetMtu (uint16_t mtu)
{
  NS_LOG_FUNCTION (mtu);
  m_mtu = mtu;
  return true;
}

uint16_t
AlohaNoackNetDevice::GetMtu (void) const
{
  NS_LOG_FUNCTION (this);
  return m_mtu;
}


void
AlohaNoackNetDevice::SetQueue (Ptr<Queue> q)
{
  NS_LOG_FUNCTION (q);
  m_queue = q;
}


void
AlohaNoackNetDevice::SetAddress (Address address)
{
  NS_LOG_FUNCTION (this);
  m_address = Mac48Address::ConvertFrom (address);
}

Address
AlohaNoackNetDevice::GetAddress (void) const
{
  NS_LOG_FUNCTION (this);
  return m_address;
}

bool
AlohaNoackNetDevice::IsBroadcast (void) const
{
  NS_LOG_FUNCTION (this);
  return true;
}

Address
AlohaNoackNetDevice::GetBroadcast (void) const
{
  NS_LOG_FUNCTION (this);
  return Mac48Address ("ff:ff:ff:ff:ff:ff");
}

bool
AlohaNoackNetDevice::IsMulticast (void) const
{
  NS_LOG_FUNCTION (this);
  return true;
}

Address
AlohaNoackNetDevice::GetMulticast (Ipv4Address addr) const
{
  NS_LOG_FUNCTION (addr);
  Mac48Address ad = Mac48Address::GetMulticast (addr);
  return ad;
}


Address AlohaNoackNetDevice::GetMulticast (Ipv6Address addr) const
{
  NS_LOG_FUNCTION (addr);
  Mac48Address ad = Mac48Address::GetMulticast (addr);
  return ad;
}


bool
AlohaNoackNetDevice::IsPointToPoint (void) const
{
  NS_LOG_FUNCTION (this);
  return false;
}

bool
AlohaNoackNetDevice::IsBridge (void) const
{
  NS_LOG_FUNCTION (this);
  return false;
}


Ptr<Node>
AlohaNoackNetDevice::GetNode (void) const
{
  NS_LOG_FUNCTION (this);
  return m_node;
}

void
AlohaNoackNetDevice::SetNode (Ptr<Node> node)
{
  NS_LOG_FUNCTION (node);

  m_node = node;
}

void
AlohaNoackNetDevice::SetPhy (Ptr<Object> phy)
{
  NS_LOG_FUNCTION (this << phy);
  m_phy = phy;
}


Ptr<Object>
AlohaNoackNetDevice::GetPhy () const
{
  NS_LOG_FUNCTION (this);
  return m_phy;
}


void
AlohaNoackNetDevice::SetChannel (Ptr<Channel> c)
{
  NS_LOG_FUNCTION (this << c);
  m_channel = c;
}


Ptr<Channel>
AlohaNoackNetDevice::GetChannel (void) const
{
  NS_LOG_FUNCTION (this);
  return m_channel;
}


bool
AlohaNoackNetDevice::NeedsArp (void) const
{
  NS_LOG_FUNCTION (this);
  return true;
}

bool
AlohaNoackNetDevice::IsLinkUp (void) const
{
  NS_LOG_FUNCTION (this);
  return m_linkUp;
}

void
AlohaNoackNetDevice::AddLinkChangeCallback (Callback<void> callback)
{
  NS_LOG_FUNCTION (&callback);
  m_linkChangeCallbacks.ConnectWithoutContext (callback);
}

void
AlohaNoackNetDevice::SetReceiveCallback (NetDevice::ReceiveCallback cb)
{
  NS_LOG_FUNCTION (&cb);
  m_rxCallback = cb;
}

void
AlohaNoackNetDevice::SetPromiscReceiveCallback (NetDevice::PromiscReceiveCallback cb)
{
  NS_LOG_FUNCTION (&cb);
  m_promiscRxCallback = cb;
}

bool
AlohaNoackNetDevice::SupportsSendFrom () const
{
  NS_LOG_FUNCTION (this);
  return true;
}


bool
AlohaNoackNetDevice::Send (Ptr<Packet> packet,const Address& dest, uint16_t protocolNumber)
{
  NS_LOG_FUNCTION (packet << dest << protocolNumber);
  return SendFrom (packet, m_address, dest, protocolNumber);
}

bool
AlohaNoackNetDevice::SendFrom (Ptr<Packet> packet, const Address& src, const Address& dest, uint16_t protocolNumber)
{
  NS_LOG_FUNCTION (packet << src << dest << protocolNumber);

  LlcSnapHeader llc;
  llc.SetType (protocolNumber);
  packet->AddHeader (llc);

  AlohaNoackMacHeader header;
  header.SetSource (Mac48Address::ConvertFrom (src));
  header.SetDestination (Mac48Address::ConvertFrom (dest));
  packet->AddHeader (header);

  m_macTxTrace (packet);



  //
  // If the device is idle, transmission starts immediately. Otherwise,
  // the transmission will be started by NotifyTransmissionEnd
  //
  NS_LOG_LOGIC (this << " state=" << m_state);
  if (m_state == IDLE)
    {
      if (m_queue->IsEmpty ())
        {
          NS_LOG_LOGIC ("new packet is head of queue, starting TX immediately");
          m_currentPkt = packet;
          StartTransmission ();
        }
      else
        {
          NS_LOG_LOGIC ("enqueueing new packet");
          if (m_queue->Enqueue (packet) == false)
            {
              m_macTxDropTrace (packet);
              return false;
            }
          NS_LOG_LOGIC ("transmitting head-of-queue packet");
          m_currentPkt = m_queue->Dequeue ();
          NS_ASSERT (m_currentPkt != 0);
          StartTransmission ();
        }
    }
  else
    {
      NS_LOG_LOGIC ("deferring TX, enqueueing new packet");
      NS_ASSERT (m_queue);
      if (m_queue->Enqueue (packet) == false)
        {
          m_macTxDropTrace (packet);
          return false;
        }
    }
  return true;
}

void
AlohaNoackNetDevice::SetPhyMacTxStartCallback (PhyMacTxStartCallback c)
{
  NS_LOG_FUNCTION (this);
  m_phyMacTxStartCallback = c;
}

void
AlohaNoackNetDevice::StartTransmission ()
{
  NS_LOG_FUNCTION (this);

  NS_ASSERT (m_currentPkt != 0);
  NS_ASSERT (m_state == IDLE);

  if (m_phyMacTxStartCallback (m_currentPkt))
    {
      NS_LOG_WARN ("PHY refused to start TX");
    }
  else
    {
      m_state = TX;
    }
}



void
AlohaNoackNetDevice::NotifyTransmissionEnd (Ptr<const Packet>)
{
  NS_LOG_FUNCTION (this);
  NS_ASSERT_MSG (m_state == TX, "TX end notified while state != TX");
  m_state = IDLE;
  NS_ASSERT (m_queue);
  if (m_queue->IsEmpty () == false)
    {
      m_currentPkt = m_queue->Dequeue ();
      NS_ASSERT (m_currentPkt);
      Simulator::ScheduleNow (&AlohaNoackNetDevice::StartTransmission, this);
    }
}


void
AlohaNoackNetDevice::NotifyReceptionStart ()
{
  NS_LOG_FUNCTION (this);
}



void
AlohaNoackNetDevice::NotifyReceptionEndError ()
{
  NS_LOG_FUNCTION (this);
}





void
AlohaNoackNetDevice::NotifyReceptionEndOk (Ptr<Packet> packet)
{
  NS_LOG_FUNCTION (this << packet);
  AlohaNoackMacHeader header;
  packet->RemoveHeader (header);
  NS_LOG_LOGIC ("packet " << header.GetSource () << " --> " << header.GetDestination () << " (here: " << m_address << ")");

  LlcSnapHeader llc;
  packet->RemoveHeader (llc);

  PacketType packetType;
  if (header.GetDestination ().IsBroadcast ())
    {
      packetType = PACKET_BROADCAST;
    }
  else if (header.GetDestination ().IsGroup ())
    {
      packetType = PACKET_MULTICAST;
    }
  else if (header.GetDestination () == m_address)
    {
      packetType = PACKET_HOST;
    }
  else
    {
      packetType = PACKET_OTHERHOST;
    }

  NS_LOG_LOGIC ("packet type = " << packetType);

  if (!m_promiscRxCallback.IsNull ())
    {
      m_promiscRxCallback (this, packet->Copy (), llc.GetType (), header.GetSource (), header.GetDestination (), packetType);
    }

  if (packetType != PACKET_OTHERHOST)
    {
      m_rxCallback (this, packet, llc.GetType (), header.GetSource () );
    }
}



} // namespace ns3
