/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2007 University of Washington
 * All rights reserved.
 *
 * 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
 */

#include "ns3/log.h"
#include "ns3/composite-trace-resolver.h"
#include "ns3/default-value.h"
#include "ns3/interface-id-default-value.h"
#include "queue.h"

NS_LOG_COMPONENT_DEFINE ("Queue");

namespace ns3 {

static InterfaceIdDefaultValue g_interfaceIdDefaultValue ("Queue", "Packet Queue",
                                                          Queue::iid (), "DropTailQueue");

NS_OBJECT_ENSURE_REGISTERED (Queue);


std::string 
QueueTraceType::GetTypeName (void) const
{
  NS_LOG_FUNCTION;
  return "ns3::QueueTraceType";
}

uint16_t 
QueueTraceType::GetUid (void)
{
  NS_LOG_FUNCTION;
  static uint16_t uid = AllocateUid<QueueTraceType> ("QueueTraceType");
  return uid;
}

QueueTraceType::QueueTraceType ()
  : m_type (QueueTraceType::ENQUEUE)
{
  NS_LOG_FUNCTION;
}

QueueTraceType::QueueTraceType (enum Type type)
  : m_type (type)
{
  NS_LOG_FUNCTION;
}

bool 
QueueTraceType::IsEnqueue (void) const
{
  NS_LOG_FUNCTION;
  return m_type == ENQUEUE;
}

bool 
QueueTraceType::IsDequeue (void) const
{
  NS_LOG_FUNCTION;
  return m_type == DEQUEUE;
}

bool 
QueueTraceType::IsDrop (void) const
{
  NS_LOG_FUNCTION;
  return m_type == DROP;
}

void 
QueueTraceType::Print (std::ostream &os) const
{
  os << "queue-";
  switch (m_type) {
  case QueueTraceType::ENQUEUE:
    os << "enqueue";
    break;
  case QueueTraceType::DEQUEUE:
    os << "dequeue";
    break;
  case QueueTraceType::DROP:
    os << "drop";
    break;
  }
}

InterfaceId 
Queue::iid (void)
{
  static InterfaceId iid = InterfaceId ("Queue")
    .SetParent<Object> ();
  return iid;
}

Queue::Queue() : 
  m_nBytes(0), 
  m_nTotalReceivedBytes(0),
  m_nPackets(0), 
  m_nTotalReceivedPackets(0),
  m_nTotalDroppedBytes(0),
  m_nTotalDroppedPackets(0)
{
  NS_LOG_FUNCTION;
}

Queue::~Queue()
{
  NS_LOG_FUNCTION;
}

Ptr<TraceResolver>
Queue::GetTraceResolver (void) const
{
  NS_LOG_FUNCTION;
  Ptr<CompositeTraceResolver> resolver = Create<CompositeTraceResolver> ();
  resolver->AddSource ("enqueue", 
                       TraceDoc ("store packet in queue",
                                 "Ptr<const Packet>", "packet queued"),
                       m_traceEnqueue, QueueTraceType (QueueTraceType::ENQUEUE));
  resolver->AddSource ("dequeue", 
                       TraceDoc ("remove packet from queue",
                                 "Ptr<const Packet>", "packet dequeued"),
                       m_traceDequeue, QueueTraceType (QueueTraceType::DEQUEUE));
  resolver->AddSource ("drop", 
                       TraceDoc ("drop packet from queue", 
                                 "Ptr<const Packet>", "packet dropped"),
                       m_traceDrop, QueueTraceType (QueueTraceType::DROP));
  resolver->SetParentResolver (Object::GetTraceResolver ());
  return resolver;
}

bool 
Queue::Enqueue (Ptr<Packet> p)
{
  NS_LOG_FUNCTION;
  NS_LOG_PARAMS (this << p);
  NS_LOG_LOGIC ("m_traceEnqueue (p)");

  m_traceEnqueue (p);

  bool retval = DoEnqueue (p);
  if (retval)
    {
      m_nBytes += p->GetSize ();
      m_nPackets++;
    }
  return retval;
}

Ptr<Packet>
Queue::Dequeue (void)
{
  NS_LOG_FUNCTION;
  NS_LOG_PARAMS (this);

  Ptr<Packet> packet = DoDequeue ();

  if (packet != 0)
    {
      m_nBytes -= packet->GetSize ();
      m_nPackets--;

      NS_ASSERT (m_nBytes >= 0);
      NS_ASSERT (m_nPackets >= 0);

      NS_LOG_LOGIC("m_traceDequeue (packet)");

      m_traceDequeue (packet);
    }
  return packet;
}

void
Queue::DequeueAll (void)
{
  NS_LOG_FUNCTION;
  NS_ASSERT_MSG (0, "Don't know what to do with dequeued packets!");
}

Ptr<Packet>
Queue::Peek (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_PARAMS (this);
  return DoPeek ();
}


uint32_t 
Queue::GetNPackets (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC ("returns " << m_nPackets);
  return m_nPackets;
}

uint32_t
Queue::GetNBytes (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC (" returns " << m_nBytes);
  return m_nBytes;
}

bool
Queue::IsEmpty (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC ("returns " << (m_nPackets == 0));
  return m_nPackets == 0;
}

uint32_t
Queue::GetTotalReceivedBytes (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC("returns " << m_nTotalReceivedBytes);
  return m_nTotalReceivedBytes;
}

uint32_t
Queue::GetTotalReceivedPackets (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC ("returns " << m_nTotalReceivedPackets);
  return m_nTotalReceivedPackets;
}

uint32_t
Queue:: GetTotalDroppedBytes (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC ("returns " << m_nTotalDroppedBytes);
  return m_nTotalDroppedBytes;
}

uint32_t
Queue::GetTotalDroppedPackets (void) const
{
  NS_LOG_FUNCTION;
  NS_LOG_LOGIC("returns " << m_nTotalDroppedPackets);
  return m_nTotalDroppedPackets;
}

void 
Queue::ResetStatistics (void)
{
  NS_LOG_FUNCTION;
  m_nTotalReceivedBytes = 0;
  m_nTotalReceivedPackets = 0;
  m_nTotalDroppedBytes = 0;
  m_nTotalDroppedPackets = 0;
}

void
Queue::Drop (Ptr<Packet> p)
{
  NS_LOG_FUNCTION;
  NS_LOG_PARAMS (this << p);

  m_nTotalDroppedPackets++;
  m_nTotalDroppedBytes += p->GetSize ();

  NS_LOG_LOGIC ("m_traceDrop (p)");
  m_traceDrop (p);
}

Ptr<Queue>
Queue::CreateDefault (void)
{
  NS_LOG_FUNCTION;
  InterfaceId interfaceId = g_interfaceIdDefaultValue.GetValue ();
  Ptr<Queue> queue = interfaceId.CreateObject ()->QueryInterface<Queue> ();
  return queue;
}

}; // namespace ns3