/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2011 University of California, Los Angeles
 *
 * 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: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
 *
 */

#include "ndn-face.hpp"

#include "ns3/packet.h"
#include "ns3/log.h"
#include "ns3/node.h"
#include "ns3/assert.h"
#include "ns3/uinteger.h"
#include "ns3/double.h"
#include "ns3/boolean.h"
#include "ns3/simulator.h"
#include "ns3/random-variable.h"
#include "ns3/pointer.h"

#include "ns3/ndn-header-helper.hpp"
#include "ns3/ndnSIM/utils/ndn-fw-hop-count-tag.hpp"

#include "ns3/ndn-wire.h"

#include <boost/ref.hpp>

NS_LOG_COMPONENT_DEFINE("ndn.Face");

namespace ns3 {
namespace ndn {

NS_OBJECT_ENSURE_REGISTERED(Face);

TypeId
Face::GetTypeId()
{
  static TypeId tid =
    TypeId("ns3::ndn::Face")
      .SetParent<Object>()
      .SetGroupName("Ndn")
      .AddAttribute("Id", "Face id (unique integer for the Ndn stack on this node)",
                    TypeId::ATTR_GET, // allow only getting it.
                    UintegerValue(0), MakeUintegerAccessor(&Face::m_id),
                    MakeUintegerChecker<uint32_t>());
  return tid;
}

/**
 * By default, Ndn face are created in the "down" state
 *  with no IP addresses.  Before becoming useable, the user must
 * invoke SetUp on them once an Ndn address and mask have been set.
 */
Face::Face(Ptr<Node> node)
  : m_node(node)
  , m_upstreamInterestHandler(MakeNullCallback<void, Ptr<Face>, Ptr<Interest>>())
  , m_upstreamDataHandler(MakeNullCallback<void, Ptr<Face>, Ptr<Data>>())
  , m_ifup(false)
  , m_id((uint32_t)-1)
  , m_metric(0)
  , m_flags(0)
{
  NS_LOG_FUNCTION(this << node);

  NS_ASSERT_MSG(node != 0, "node cannot be NULL. Check the code");
}

Face::~Face()
{
  NS_LOG_FUNCTION_NOARGS();
}

Face::Face(const Face&)
{
}

Face& Face::operator= (const Face &)
{
  return *this;
}

Ptr<Node>
Face::GetNode() const
{
  return m_node;
}

void
Face::RegisterProtocolHandlers(const InterestHandler& interestHandler,
                               const DataHandler& dataHandler)
{
  NS_LOG_FUNCTION_NOARGS();

  m_upstreamInterestHandler = interestHandler;
  m_upstreamDataHandler = dataHandler;
}

void
Face::UnRegisterProtocolHandlers()
{
  NS_LOG_FUNCTION_NOARGS();

  m_upstreamInterestHandler = MakeNullCallback<void, Ptr<Face>, Ptr<Interest>>();
  m_upstreamDataHandler = MakeNullCallback<void, Ptr<Face>, Ptr<Data>>();
}

bool
Face::SendInterest(Ptr<const Interest> interest)
{
  NS_LOG_FUNCTION(this << boost::cref(*this) << interest->GetName());

  if (!IsUp()) {
    return false;
  }

  return Send(Wire::FromInterest(interest));
}

bool
Face::SendData(Ptr<const Data> data)
{
  NS_LOG_FUNCTION(this << data);

  if (!IsUp()) {
    return false;
  }

  return Send(Wire::FromData(data));
}

bool
Face::Send(Ptr<Packet> packet)
{
  FwHopCountTag hopCount;
  bool tagExists = packet->RemovePacketTag(hopCount);
  if (tagExists) {
    hopCount.Increment();
    packet->AddPacketTag(hopCount);
  }

  return true;
}

bool
Face::Receive(Ptr<const Packet> p)
{
  NS_LOG_FUNCTION(this << p << p->GetSize());

  if (!IsUp()) {
    // no tracing here. If we were off while receiving, we shouldn't even know that something was
    // there
    return false;
  }

  Ptr<Packet> packet = p->Copy(); // give upper layers a rw copy of the packet
  try {
    HeaderHelper::Type type = HeaderHelper::GetNdnHeaderType(packet);
    switch (type) {
    case HeaderHelper::INTEREST_NDNSIM:
      return ReceiveInterest(Wire::ToInterest(packet, Wire::WIRE_FORMAT_NDNSIM));
    case HeaderHelper::INTEREST_CCNB:
      return ReceiveInterest(Wire::ToInterest(packet, Wire::WIRE_FORMAT_CCNB));
    case HeaderHelper::CONTENT_OBJECT_NDNSIM:
      return ReceiveData(Wire::ToData(packet, Wire::WIRE_FORMAT_NDNSIM));
    case HeaderHelper::CONTENT_OBJECT_CCNB:
      return ReceiveData(Wire::ToData(packet, Wire::WIRE_FORMAT_CCNB));
    default:
      NS_FATAL_ERROR("Not supported NDN header");
      return false;
    }

    // exception will be thrown if packet is not recognized
  }
  catch (UnknownHeaderException) {
    NS_FATAL_ERROR("Unknown NDN header. Should not happen");
    return false;
  }

  return false;
}

bool
Face::ReceiveInterest(Ptr<Interest> interest)
{
  if (!IsUp()) {
    // no tracing here. If we were off while receiving, we shouldn't even know that something was
    // there
    return false;
  }

  m_upstreamInterestHandler(this, interest);
  return true;
}

bool
Face::ReceiveData(Ptr<Data> data)
{
  if (!IsUp()) {
    // no tracing here. If we were off while receiving, we shouldn't even know that something was
    // there
    return false;
  }

  m_upstreamDataHandler(this, data);
  return true;
}

void
Face::SetMetric(uint16_t metric)
{
  NS_LOG_FUNCTION(metric);
  m_metric = metric;
}

uint16_t
Face::GetMetric(void) const
{
  return m_metric;
}

void
Face::SetFlags(uint32_t flags)
{
  m_flags = flags;
}

bool
Face::operator== (const Face &face) const
{
  NS_ASSERT_MSG(m_node->GetId() == face.m_node->GetId(),
                "Faces of different nodes should not be compared to each other: " << *this << " == "
                                                                                  << face);

  return (m_id == face.m_id);
}

bool
Face::operator< (const Face &face) const
{
  NS_ASSERT_MSG(m_node->GetId() == face.m_node->GetId(),
                "Faces of different nodes should not be compared to each other: " << *this << " == "
                                                                                  << face);

  return (m_id < face.m_id);
}

std::ostream&
Face::Print(std::ostream& os) const
{
  os << "id=" << GetId();
  return os;
}

std::ostream&
operator<<(std::ostream& os, const Face& face)
{
  face.Print(os);
  return os;
}

} // namespace ndn
} // namespace ns3