/*
 * Copyright (c) 2015 Universita' degli Studi di Napoli "Federico II"
 *               2017 Kungliga Tekniska Högskolan
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Author: Pasquale Imputato <p.imputato@gmail.com>
 * Author: Stefano Avallone <stefano.avallone@unina.it>
 * Author: Surya Seetharaman <suryaseetharaman.9@gmail.com> - ported from ns-3
 *         RedQueueDisc traffic-control example to accommodate TbfQueueDisc example.
 */

#include "ns3/applications-module.h"
#include "ns3/core-module.h"
#include "ns3/internet-module.h"
#include "ns3/network-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/traffic-control-module.h"

// This simple example shows how to use TrafficControlHelper to install a
// QueueDisc on a device.
//
// Network topology
//
//       10.1.1.0
// n0 -------------- n1
//    point-to-point
//
// The output will consist of all the traced changes in
// the number of tokens in TBF's first and second buckets:
//
//    FirstBucketTokens 0 to x
//    SecondBucketTokens 0 to x
//    FirstBucketTokens x to 0
//    SecondBucketTokens x to 0
//

using namespace ns3;

NS_LOG_COMPONENT_DEFINE("TbfExample");

void
FirstBucketTokensTrace(uint32_t oldValue, uint32_t newValue)
{
    std::cout << "FirstBucketTokens " << oldValue << " to " << newValue << std::endl;
}

void
SecondBucketTokensTrace(uint32_t oldValue, uint32_t newValue)
{
    std::cout << "SecondBucketTokens " << oldValue << " to " << newValue << std::endl;
}

int
main(int argc, char* argv[])
{
    double simulationTime = 10; // seconds
    uint32_t burst = 10000;
    uint32_t mtu = 0;
    DataRate rate = DataRate("1Mbps");
    DataRate peakRate = DataRate("0bps");

    CommandLine cmd(__FILE__);
    cmd.AddValue("burst", "Size of first bucket in bytes", burst);
    cmd.AddValue("mtu", "Size of second bucket in bytes", mtu);
    cmd.AddValue("rate", "Rate of tokens arriving in first bucket", rate);
    cmd.AddValue("peakRate", "Rate of tokens arriving in second bucket", peakRate);

    cmd.Parse(argc, argv);

    NodeContainer nodes;
    nodes.Create(2);

    PointToPointHelper pointToPoint;
    pointToPoint.SetDeviceAttribute("DataRate", StringValue("2Mb/s"));
    pointToPoint.SetChannelAttribute("Delay", StringValue("0ms"));

    NetDeviceContainer devices;
    devices = pointToPoint.Install(nodes);

    InternetStackHelper stack;
    stack.Install(nodes);

    TrafficControlHelper tch;
    tch.SetRootQueueDisc("ns3::TbfQueueDisc",
                         "Burst",
                         UintegerValue(burst),
                         "Mtu",
                         UintegerValue(mtu),
                         "Rate",
                         DataRateValue(DataRate(rate)),
                         "PeakRate",
                         DataRateValue(DataRate(peakRate)));
    QueueDiscContainer qdiscs = tch.Install(devices);

    Ptr<QueueDisc> q = qdiscs.Get(1);
    q->TraceConnectWithoutContext("TokensInFirstBucket", MakeCallback(&FirstBucketTokensTrace));
    q->TraceConnectWithoutContext("TokensInSecondBucket", MakeCallback(&SecondBucketTokensTrace));

    Ipv4AddressHelper address;
    address.SetBase("10.1.1.0", "255.255.255.0");

    Ipv4InterfaceContainer interfaces = address.Assign(devices);

    // Flow
    uint16_t port = 7;
    Address localAddress(InetSocketAddress(Ipv4Address::GetAny(), port));
    PacketSinkHelper packetSinkHelper("ns3::TcpSocketFactory", localAddress);
    ApplicationContainer sinkApp = packetSinkHelper.Install(nodes.Get(0));

    sinkApp.Start(Seconds(0));
    sinkApp.Stop(Seconds(simulationTime + 0.1));

    uint32_t payloadSize = 1448;
    Config::SetDefault("ns3::TcpSocket::SegmentSize", UintegerValue(payloadSize));

    OnOffHelper onoff("ns3::TcpSocketFactory", Ipv4Address::GetAny());
    onoff.SetAttribute("OnTime", StringValue("ns3::ConstantRandomVariable[Constant=1]"));
    onoff.SetAttribute("OffTime", StringValue("ns3::ConstantRandomVariable[Constant=0.2]"));
    onoff.SetAttribute("PacketSize", UintegerValue(payloadSize));
    onoff.SetAttribute("DataRate", StringValue("1.1Mb/s")); // bit/s
    ApplicationContainer apps;

    InetSocketAddress rmt(interfaces.GetAddress(0), port);
    onoff.SetAttribute("Remote", AddressValue(rmt));
    onoff.SetAttribute("Tos", UintegerValue(0xb8));

    apps.Add(onoff.Install(nodes.Get(1)));
    apps.Start(Seconds(1));
    apps.Stop(Seconds(simulationTime + 0.1));

    Simulator::Stop(Seconds(simulationTime + 5));
    Simulator::Run();

    Simulator::Destroy();

    std::cout << std::endl << "*** TC Layer statistics ***" << std::endl;
    std::cout << q->GetStats() << std::endl;
    return 0;
}
