// ns-3

#include "ns3/command-line.h"
#include "ns3/config.h"
#include "ns3/string.h"
#include "ns3/log.h"
#include "ns3/yans-wifi-helper.h"
#include "ns3/ssid.h"
#include "ns3/mobility-helper.h"
#include "ns3/on-off-helper.h"
#include "ns3/yans-wifi-channel.h"
#include "ns3/mobility-model.h"
#include "ns3/packet-sink.h"
#include "ns3/packet-sink-helper.h"
#include "ns3/udp-echo-helper.h"
#include "ns3/tcp-westwood.h"
#include "ns3/internet-stack-helper.h"
#include "ns3/ipv4-address-helper.h"
#include "ns3/ipv4-global-routing-helper.h"
#include "ns3/constant-position-mobility-model.h"

// C++ library
#include <iostream>
#include <utility> // To use std::pair

using namespace ns3;
NS_LOG_COMPONENT_DEFINE ("wifi-tcp");




// ---------- Code ----------
// Cell tuple like ((APNode,SensorNodes),(APNetDev,SensorsNetDev))
typedef std::pair<NodeContainer,NodeContainer> CellNodes;
typedef std::pair<NetDeviceContainer,NetDeviceContainer> CellNetDevices;
typedef std::pair<CellNodes,CellNetDevices> Cell;

/**
 * Create a sensors cell
 */
Cell createCell(uint32_t nbSensors){
  // Create sensors
  NodeContainer sensors;
  sensors.Create(nbSensors);
  NodeContainer ap;
  ap.Create(1);

  // Place nodes somehow, this is required by every wireless simulation
  for (uint8_t i = 0; i < nbSensors; ++i)
    {
      sensors.Get (i)->AggregateObject (CreateObject<ConstantPositionMobilityModel> ());
    }
  ap.Get (0)->AggregateObject (CreateObject<ConstantPositionMobilityModel> ());

  // To apply XXWifiPhy and WifiMac on sensors 
  WifiHelper wifiHelper;
  wifiHelper.SetStandard (WIFI_PHY_STANDARD_80211n_5GHZ);

  /* Set up Legacy Channel */
  YansWifiChannelHelper wifiChannel;
  wifiChannel.SetPropagationDelay ("ns3::ConstantSpeedPropagationDelayModel");
  wifiChannel.AddPropagationLoss ("ns3::FriisPropagationLossModel", "Frequency", DoubleValue (5e9));

  /* Setup Physical Layer */
  YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default ();
  wifiPhy.SetChannel (wifiChannel.Create ());
  wifiPhy.Set ("TxPowerStart", DoubleValue (10.0));
  wifiPhy.Set ("TxPowerEnd", DoubleValue (10.0));
  wifiPhy.Set ("TxPowerLevels", UintegerValue (1));
  wifiPhy.Set ("TxGain", DoubleValue (0));
  wifiPhy.Set ("RxGain", DoubleValue (0));
  wifiPhy.Set ("RxNoiseFigure", DoubleValue (10));
  wifiPhy.Set ("CcaMode1Threshold", DoubleValue (-79));
  wifiPhy.Set ("EnergyDetectionThreshold", DoubleValue (-79 + 3));
  //  wifiPhy.SetErrorRateModel ("ns3::YansErrorRateModel");
  wifiHelper.SetRemoteStationManager ("ns3::ConstantRateWifiManager",
                                      "DataMode", StringValue ("HtMcs7"),
                                      "ControlMode", StringValue ("HtMcs0"));
  /* Configure AP */
  Ssid ssid = Ssid ("network");
  WifiMacHelper wifiMac;
  wifiMac.SetType ("ns3::ApWifiMac", "Ssid", SsidValue (ssid));
  NetDeviceContainer apNetDevice;
  apNetDevice = wifiHelper.Install (wifiPhy, wifiMac, ap);
  /* Configure STA */
  wifiMac.SetType ("ns3::StaWifiMac", "Ssid", SsidValue (ssid));
  NetDeviceContainer sensorsNetDevices;
  sensorsNetDevices = wifiHelper.Install (wifiPhy, wifiMac, sensors);

  return(std::make_pair(std::make_pair(ap,sensors),std::make_pair(apNetDevice,sensorsNetDevices)));
}

/**
 * Install network stack and applications
 */
void applyScenarios(Cell cell,int sensorsPktSize, int sensorsSendInterval){
  NodeContainer ap=cell.first.first;
  NodeContainer sensors=cell.first.second;
  NetDeviceContainer apNetDev= cell.second.first;
  NetDeviceContainer sensorsNetDev= cell.second.second;
  
  // 6. Install TCP/IP stack & assign IP addresses
  InternetStackHelper internet;
  internet.Install (ap);
  internet.Install (sensors);
  Ipv4AddressHelper ipv4;
  ipv4.SetBase ("10.0.0.0", "255.0.0.0");
  Ipv4InterfaceContainer apInt,sensorsInt;
  apInt=ipv4.Assign(apNetDev);
  sensorsInt=ipv4.Assign(sensorsNetDev);

  uint16_t  echoPort = 9;
  UdpEchoClientHelper echoClientHelper (InetSocketAddress (apInt.GetAddress (0), echoPort));
  //  echoClientHelper.SetAttribute ("MaxPackets", UintegerValue (10));
  echoClientHelper.SetAttribute ("Interval", TimeValue (Seconds (sensorsSendInterval)));
  echoClientHelper.SetAttribute ("PacketSize", UintegerValue (sensorsPktSize));
  ApplicationContainer pingApps;

  // again using different start times to workaround Bug 388 and Bug 912
  echoClientHelper.SetAttribute ("StartTime", TimeValue (Seconds (1))); // Start at 1 (WIFI seems to not work when t<1)
  echoClientHelper.Install (sensors);

  PacketSinkHelper apSink("ns3::UdpSocketFactory",InetSocketAddress (Ipv4Address::GetAny (), echoPort));
  ApplicationContainer sinkApp=apSink.Install(ap);
  sinkApp.Start (Seconds (0));
}

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

  LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_INFO);
  LogComponentEnable("PacketSink", LOG_LEVEL_INFO);

  uint32_t sensorsFrequency=1;
  uint32_t sensorsPktSize=150;
  uint32_t sensorsNumber=10;

  CommandLine cmd;
  cmd.AddValue ("sensorsSendInterval", "Number of temperature measurement per second (default 1)", sensorsFrequency);
  cmd.AddValue ("sensorsPktSize", "Sensor measurements packet size (default 64 bytes)", sensorsPktSize);
  cmd.AddValue ("sensorsNumber", "Number of sensors (default 10)", sensorsNumber);
  cmd.Parse (argc, argv);


  Cell c=createCell(sensorsNumber);
  applyScenarios(c,sensorsPktSize,sensorsFrequency);

  // Run simulators
  Simulator::Stop (Seconds (10));
  Simulator::Run ();

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