/*
 * UdpEchoClient                            UdpEchoServer
 *            10.1.1.0               10.1.2.0
 *      n1 ------------------n2------------------n3
 *         point-to-point       point-to-point
 */

#include <ns3/core-module.h>
#include <ns3/network-module.h>
#include <ns3/internet-module.h>
#include <ns3/point-to-point-module.h>
#include <ns3/applications-module.h>

using namespace ns3;

int main ()
{
  LogComponentEnable ("UdpEchoClientApplication", LOG_LEVEL_INFO);
  LogComponentEnable ("UdpEchoServerApplication", LOG_LEVEL_INFO);

  NodeContainer allNodes, nodes12, nodes23;
  allNodes.Create (3);
  nodes12.Add (allNodes.Get (0));
  nodes12.Add (allNodes.Get (1));
  nodes23.Add (allNodes.Get (1));
  nodes23.Add (allNodes.Get (2));

  PointToPointHelper pointToPoint;
  pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("15Mbps"));
  pointToPoint.SetChannelAttribute ("Delay", StringValue ("44ms"));

  NetDeviceContainer devices12, devices23;
  devices12 = pointToPoint.Install (nodes12);
  devices23 = pointToPoint.Install (nodes23);
  // pointToPoint.EnablePcapAll ("vjezba-udp-echo-neizravna-veza");

  InternetStackHelper stack;
  stack.Install (allNodes);

  Ipv4AddressHelper address;
  address.SetBase ("10.1.1.0", "255.255.255.0");
  Ipv4InterfaceContainer interfaces12 = address.Assign (devices12);

  address.SetBase ("10.1.2.0", "255.255.255.0");
  Ipv4InterfaceContainer interfaces23 = address.Assign (devices23);

  Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

  UdpEchoServerHelper echoServer (9);

  ApplicationContainer serverApps = echoServer.Install (allNodes.Get (2));
  serverApps.Start (Seconds (1.0));
  serverApps.Stop (Seconds (10.0));

  UdpEchoClientHelper echoClient (interfaces23.GetAddress (1), 9);
  echoClient.SetAttribute ("MaxPackets", UintegerValue (1));
  echoClient.SetAttribute ("Interval", TimeValue (Seconds (1.0)));
  echoClient.SetAttribute ("PacketSize", UintegerValue (1024));

  ApplicationContainer clientApps = echoClient.Install (allNodes.Get (0));
  clientApps.Start (Seconds (2.0));
  clientApps.Stop (Seconds (10.0));

  Simulator::Run ();
  Simulator::Destroy ();
  return 0;
}