/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright 2007 University of Washington
 * 
 * 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/ipv4-address.h"
#include "ns3/nstime.h"
#include "ns3/inet-socket-address.h"
#include "ns3/socket.h"
#include "ns3/simulator.h"
#include "ns3/socket-factory.h"
#include "ns3/packet.h"
#include "ns3/uinteger.h"
#include "udp-echo-client.h"

namespace ns3 {

NS_LOG_COMPONENT_DEFINE ("UdpEchoClientApplication");
NS_OBJECT_ENSURE_REGISTERED (UdpEchoClient);

TypeId
UdpEchoClient::GetTypeId (void)
{
  static TypeId tid = TypeId ("ns3::UdpEchoClient")
    .SetParent<Application> ()
    .AddConstructor<UdpEchoClient> ()
    .AddAttribute ("MaxPackets", "XXX",
                   UintegerValue (100),
                   MakeUintegerAccessor (&UdpEchoClient::m_count),
                   MakeUintegerChecker<uint32_t> ())
    .AddAttribute ("Interval", "XXX",
                   TimeValue (Seconds (1.0)),
                   MakeTimeAccessor (&UdpEchoClient::m_interval),
                   MakeTimeChecker ())
    .AddAttribute ("RemoteIpv4", "XXX",
                   Ipv4AddressValue (),
                   MakeIpv4AddressAccessor (&UdpEchoClient::m_peerAddress),
                   MakeIpv4AddressChecker ())
    .AddAttribute ("RemotePort", "XXX",
                   UintegerValue (0),
                   MakeUintegerAccessor (&UdpEchoClient::m_peerPort),
                   MakeUintegerChecker<uint16_t> ())
    .AddAttribute ("PacketSize", "Size of packets generated",
                   UintegerValue (100),
                   MakeUintegerAccessor (&UdpEchoClient::m_size),
                   MakeUintegerChecker<uint32_t> ())
    ;
  return tid;
}

UdpEchoClient::UdpEchoClient ()
{
  NS_LOG_FUNCTION_NOARGS ();
  m_sent = 0;
  m_socket = 0;
  m_sendEvent = EventId ();
}

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

void 
UdpEchoClient::SetRemote (Ipv4Address ip, uint16_t port)
{
  m_peerAddress = ip;
  m_peerPort = port;
}

void
UdpEchoClient::DoDispose (void)
{
  NS_LOG_FUNCTION_NOARGS ();
  Application::DoDispose ();
}

void 
UdpEchoClient::StartApplication (void)
{
  NS_LOG_FUNCTION_NOARGS ();

  if (!m_socket)
    {
      TypeId tid = TypeId::LookupByName ("ns3::UdpSocketFactory");
      m_socket = Socket::CreateSocket (GetNode(), tid);
      m_socket->Bind ();
      m_socket->Connect (InetSocketAddress (m_peerAddress, m_peerPort));
    }

  m_socket->SetRecvCallback(MakeCallback(&UdpEchoClient::HandleRead, this));

  ScheduleTransmit (Seconds(0.));
}

void 
UdpEchoClient::StopApplication ()
{
  NS_LOG_FUNCTION_NOARGS ();

  if (!m_socket) 
    {
      m_socket->SetRecvCallback(MakeNullCallback<void, Ptr<Socket> > ());
    }

  Simulator::Cancel(m_sendEvent);
}

void 
UdpEchoClient::ScheduleTransmit (Time dt)
{
  NS_LOG_FUNCTION_NOARGS ();
  m_sendEvent = Simulator::Schedule(dt, &UdpEchoClient::Send, this);
}

void 
UdpEchoClient::Send (void)
{
  NS_LOG_FUNCTION_NOARGS ();

  NS_ASSERT (m_sendEvent.IsExpired ());

  Ptr<Packet> p = Create<Packet> (m_size);
  m_socket->Send (p);
  ++m_sent;

  NS_LOG_INFO ("Sent " << m_size << " bytes to " << m_peerAddress);

  if (m_sent < m_count) 
    {
      ScheduleTransmit (m_interval);
    }
}

void
UdpEchoClient::HandleRead (Ptr<Socket> socket)
{
  NS_LOG_FUNCTION (this << socket);
  Ptr<Packet> packet;
  while (packet = socket->Recv ())
    {
      SocketRxAddressTag tag;
      bool found = packet->PeekTag (tag);
      NS_ASSERT (found);
      Address from = tag.GetAddress ();
      packet->RemoveTag (tag);
      if (InetSocketAddress::IsMatchingType (from))
        {
          InetSocketAddress address = InetSocketAddress::ConvertFrom (from);
          NS_LOG_INFO ("Received " << packet->GetSize() << " bytes from " <<
            address.GetIpv4());
        }
    }
}

} // Namespace ns3