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

//
// Network topology
//
//           10Mb/s, 10ms       10Mb/s, 10ms
//       n0-----------------n1-----------------n2
//
//
// - Tracing of queues and packet receptions to file 
//   "tcp-large-transfer-errors.tr"
// - pcap traces also generated in the following files
//   "tcp-large-transfer-errors.pcap-$n-$i" where n and i represent node and interface numbers respectively
//  Usage (e.g.): ./waf --run tcp-large-transfer-errors

#include <ctype.h>
#include <iostream>
#include <fstream>
#include <string>
#include <cassert>

#include "ns3/command-line.h"
#include "ns3/ptr.h"
#include "ns3/random-variable.h"
#include "ns3/log.h"

#include "ns3/simulator.h"
#include "ns3/nstime.h"
#include "ns3/data-rate.h"

#include "ns3/ascii-trace.h"
#include "ns3/pcap-trace.h"
#include "ns3/internet-node.h"
#include "ns3/point-to-point-channel.h"
#include "ns3/point-to-point-net-device.h"
#include "ns3/ipv4-address.h"
#include "ns3/inet-socket-address.h"
#include "ns3/ipv4.h"
#include "ns3/socket.h"
#include "ns3/ipv4-route.h"
#include "ns3/point-to-point-topology.h"
#include "ns3/onoff-application.h"
#include "ns3/packet-sink.h"
#include "ns3/error-model.h"
#include "ns3/node-list.h"
#include "ns3/config.h"

#include "ns3/tcp.h"

using namespace ns3;

NS_LOG_COMPONENT_DEFINE ("TcpLargeTransferErrors");

void 
ApplicationTraceSink (Ptr<const Packet> packet,
                      const Address &addr)
{
// g_log is not declared in optimized builds
// should convert this to use of some other flag than the logging system
#ifdef NS3_LOG_ENABLE
  if (!g_log.IsNoneEnabled ()) {
    if (InetSocketAddress::IsMatchingType (addr) )
      {
      InetSocketAddress address = InetSocketAddress::ConvertFrom (addr);
        std::cout << "PacketSink received size " << 
        packet->GetSize () << " at time " << 
        Simulator::Now ().GetSeconds () << " from address: " << 
        address.GetIpv4 () << std::endl;
        char buf[2000]; 
        memcpy(buf, packet->PeekData (), packet->GetSize ());
        for (uint32_t i=0; i < packet->GetSize (); i++)
          {
            std::cout << buf[i];
            if (i && i % 60 == 0) 
              std::cout << std::endl; 
          }
        std::cout << std::endl << std::endl;
    }
  }
#endif
}

void CloseConnection (Ptr<Socket> localSocket)
{
  //localSocket->Close ();
}

void StartFlow(Ptr<Socket> localSocket, uint32_t nBytes, 
  uint16_t servPort)
{
 // NS_LOG_LOGIC("Starting flow at time " <<  Simulator::Now ().GetSeconds ());
  localSocket->Connect (InetSocketAddress ("10.1.2.2", servPort));//connect
  localSocket->SetConnectCallback (MakeCallback (&CloseConnection),
                                   Callback<void, Ptr<Socket> > (),
                                   Callback<void, Ptr<Socket> > ());
  //we want to close as soon as the connection is established
  //the tcp state machine and outgoing buffer will assure that
  //all of the data is delivered

  // Perform series of 1040 byte writes (this is a multiple of 26 since
  // we want to detect data splicing in the output stream)
  uint32_t writeSize = 1040;
  uint8_t data[writeSize];
  while (nBytes > 0) {
    uint32_t curSize= nBytes > writeSize ? writeSize : nBytes;
    for(uint32_t i = 0; i < curSize; ++i)
    {
      char m = toascii (97 + i % 26);
      data[i] = m;
    }
    localSocket->Send (data, curSize);
    nBytes -= curSize;
  }
}

int main (int argc, char *argv[])
{

  // Users may find it convenient to turn on explicit debugging
  // for selected modules; the below lines suggest how to do this
//  LogComponentEnable("TcpL4Protocol", LOG_LEVEL_ALL);
//  LogComponentEnable("TcpSocket", LOG_LEVEL_ALL);
//  LogComponentEnable("PacketSink", LOG_LEVEL_ALL);
  //LogComponentEnable("TcpLargeTransferErrors", LOG_LEVEL_ALL);

  // Allow the user to override any of the defaults and the above
  // Bind()s at run-time, via command-line arguments
  CommandLine cmd;
  cmd.Parse (argc, argv);

  // Here, we will explicitly create three nodes.  In more sophisticated
  // topologies, we could configure a node factory.
  Ptr<Node> n0 = Create<InternetNode> ();
  Ptr<Node> n1 = Create<InternetNode> (); 
  Ptr<Node> n2 = Create<InternetNode> ();

  // We create the channels first without any IP addressing information
  Ptr<PointToPointChannel> channel0 = 
    PointToPointTopology::AddPointToPointLink (
    n0, n1, DataRate(10000000), MilliSeconds(10));
  
  // Later, we add IP addresses.  
  PointToPointTopology::AddIpv4Addresses (
      channel0, n0, Ipv4Address("10.1.3.1"),
      n1, Ipv4Address("10.1.3.2"));

  Ptr<PointToPointChannel> channel1 = 
      PointToPointTopology::AddPointToPointLink (
      n1, n2, DataRate(10000000), MilliSeconds(10));
  
  PointToPointTopology::AddIpv4Addresses (
      channel1, n1, Ipv4Address("10.1.2.1"),
      n2, Ipv4Address("10.1.2.2"));
  
  // Finally, we add static routes.  These three steps (Channel and
  // NetDevice creation, IP Address assignment, and routing) are 
  // separated because there may be a need to postpone IP Address
  // assignment (emulation) or modify to use dynamic routing
  PointToPointTopology::AddIpv4Routes(n0, n1, channel0);
  PointToPointTopology::AddIpv4Routes(n1, n2, channel1);
  Ptr<Ipv4> ipv4;
  ipv4 = n0->GetObject<Ipv4> ();
  ipv4->SetDefaultRoute (Ipv4Address ("10.1.3.2"), 1);
  ipv4 = n2->GetObject<Ipv4> ();
  ipv4->SetDefaultRoute (Ipv4Address ("10.1.2.1"), 1);


  ///////////////////////////////////////////////////////////////////////////
  // Simulation 1
  // 
  // Send 2000000 bytes over a connection to server port 50000 at time 0
  // Should observe SYN exchange, a lot of data segments, and FIN exchange
  //
  ///////////////////////////////////////////////////////////////////////////

  int nBytes = 2000000;
  uint16_t servPort = 50000;

  Ptr<SocketFactory> socketFactory = 
    n0->GetObject<SocketFactory> ();
  Ptr<Socket> localSocket = socketFactory->CreateSocket ();
  localSocket->Bind ();

  // Create a packet sink to receive these packets
  Ptr<PacketSink> sink = 
    CreateObject<PacketSink> ("Local", Address (InetSocketAddress (Ipv4Address::GetAny (), servPort)),
                              "Protocol", TypeId::LookupByName ("ns3::Tcp"));
  n2->AddApplication (sink);
  sink->Start (Seconds (0.0));
  sink->Stop (Seconds (10000.0));

 //
  // Error models
  //
  // We want to add an error model to node 2's NetDevice
  // We can obtain a handle to the NetDevice via the channel and node 
  // pointers
  Ptr<PointToPointNetDevice> nd2 = PointToPointTopology::GetNetDevice
    (n2, channel1);
  Ptr<RateErrorModel> rem = Create<RateErrorModel> ();
  // The first data segment for this flow is packet uid=4
  rem->SetRandomVariable (UniformVariable ());
  rem->SetUnit (EU_PKT);
  rem->SetRate (0.05);
  nd2->AddReceiveErrorModel (rem);

  Simulator::Schedule(Seconds(0), &StartFlow, localSocket, nBytes,
    servPort);

  // Configure tracing of all enqueue, dequeue, and NetDevice receive events
  // Trace output will be sent to the simple-examples.tr file
  AsciiTrace asciitrace ("tcp-large-transfer-errors.tr");
  asciitrace.TraceAllQueues ();
  asciitrace.TraceAllNetDeviceRx ();

  
  // Also configure some tcpdump traces; each interface will be traced
  // The output files will be named 
  // simple-examples.pcap-<nodeId>-<interfaceId>
  // and can be read by the "tcpdump -r" command (use "-tt" option to
  // display timestamps correctly)
  PcapTrace pcaptrace ("tcp-large-transfer-errors.pcap");
  pcaptrace.TraceAllIp ();

  Config::ConnectWithoutContext ("/NodeList/*/ApplicationList/*/Rx", MakeCallback (&ApplicationTraceSink));

  Simulator::StopAt (Seconds(10000));
  Simulator::Run ();
  Simulator::Destroy ();
}