/*
 * Copyright (c) 2009 Strasbourg University
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Author: David Gross <gdavid.devel@gmail.com>
 *         Sebastien Vincent <vincent@clarinet.u-strasbg.fr>
 */

// Network topology
// //
// //             n0   R    n1
// //             |    _    |
// //             ====|_|====
// //                router
// // - R sends RA to n0's subnet (2001:1::/64 and 2001:ABCD::/64);
// // - R interface to n0 has two addresses with following prefixes 2001:1::/64 and 2001:ABCD::/64;
// // - R sends RA to n1's subnet (2001:2::/64);
// // - n0 ping n1.
// //
// // - Tracing of queues and packet receptions to file "radvd-two-prefix.tr"

#include "ns3/core-module.h"
#include "ns3/csma-module.h"
#include "ns3/internet-apps-module.h"
#include "ns3/internet-module.h"
#include "ns3/ipv6-routing-table-entry.h"
#include "ns3/ipv6-static-routing-helper.h"
#include "ns3/radvd-interface.h"
#include "ns3/radvd-prefix.h"
#include "ns3/radvd.h"

#include <fstream>

using namespace ns3;

NS_LOG_COMPONENT_DEFINE("RadvdTwoPrefixExample");

/**
 * @class IpAddressHelper
 * @brief Helper to print a node's IP addresses.
 */
class IpAddressHelper
{
  public:
    /**
     * @brief Print the node's IP addresses.
     * @param n the node
     */
    inline void PrintIpAddresses(Ptr<Node>& n)
    {
        Ptr<Ipv6> ipv6 = n->GetObject<Ipv6>();
        uint32_t nInterfaces = ipv6->GetNInterfaces();

        std::cout << "Node: " << ipv6->GetObject<Node>()->GetId()
                  << " Time: " << Simulator::Now().GetSeconds() << "s "
                  << "IPv6 addresses" << std::endl;
        std::cout << "(Interface index, Address index)\t"
                  << "IPv6 Address" << std::endl;

        for (uint32_t i = 0; i < nInterfaces; i++)
        {
            for (uint32_t j = 0; j < ipv6->GetNAddresses(i); j++)
            {
                std::cout << "(" << int(i) << "," << int(j) << ")\t" << ipv6->GetAddress(i, j)
                          << std::endl;
            }
        }
        std::cout << std::endl;
    }
};

int
main(int argc, char** argv)
{
    bool verbose = false;

    CommandLine cmd(__FILE__);
    cmd.AddValue("verbose", "turn on log components", verbose);
    cmd.Parse(argc, argv);

    if (verbose)
    {
        LogComponentEnable("Ipv6L3Protocol", LOG_LEVEL_ALL);
        LogComponentEnable("Ipv6RawSocketImpl", LOG_LEVEL_ALL);
        LogComponentEnable("Icmpv6L4Protocol", LOG_LEVEL_ALL);
        LogComponentEnable("Ipv6StaticRouting", LOG_LEVEL_ALL);
        LogComponentEnable("Ipv6Interface", LOG_LEVEL_ALL);
        LogComponentEnable("RadvdApplication", LOG_LEVEL_ALL);
        LogComponentEnable("Ping", LOG_LEVEL_ALL);
    }

    NS_LOG_INFO("Create nodes.");
    Ptr<Node> n0 = CreateObject<Node>();
    Ptr<Node> r = CreateObject<Node>();
    Ptr<Node> n1 = CreateObject<Node>();

    NodeContainer net1(n0, r);
    NodeContainer net2(r, n1);
    NodeContainer all(n0, r, n1);

    NS_LOG_INFO("Create IPv6 Internet Stack");
    InternetStackHelper internetv6;
    internetv6.Install(all);

    NS_LOG_INFO("Create channels.");
    CsmaHelper csma;
    csma.SetChannelAttribute("DataRate", DataRateValue(5000000));
    csma.SetChannelAttribute("Delay", TimeValue(MilliSeconds(2)));
    NetDeviceContainer d1 = csma.Install(net1); /* n0 - R */
    NetDeviceContainer d2 = csma.Install(net2); /* R - n1 */

    NS_LOG_INFO("Create networks and assign IPv6 Addresses.");
    Ipv6AddressHelper ipv6;

    /* first subnet */
    ipv6.SetBase(Ipv6Address("2001:1::"), Ipv6Prefix(64));
    NetDeviceContainer tmp;
    tmp.Add(d1.Get(0));                                           /* n0 */
    Ipv6InterfaceContainer iic1 = ipv6.AssignWithoutAddress(tmp); /* n0 interface */

    NetDeviceContainer tmp2;
    tmp2.Add(d1.Get(1)); /* R */
    Ipv6InterfaceContainer iicr1 =
        ipv6.Assign(tmp2); /* R interface to the first subnet is just statically assigned */
    iicr1.SetForwarding(0, true);
    iic1.Add(iicr1);

    /* add another IPv6 address for second prefix advertised on first subnet */
    ipv6.SetBase(Ipv6Address("2001:ABCD::"), Ipv6Prefix(64));
    ipv6.Assign(tmp2);

    /* second subnet R - n1 */
    ipv6.SetBase(Ipv6Address("2001:2::"), Ipv6Prefix(64));
    NetDeviceContainer tmp3;
    tmp3.Add(d2.Get(0));                              /* R */
    Ipv6InterfaceContainer iicr2 = ipv6.Assign(tmp3); /* R interface */
    iicr2.SetForwarding(0, true);

    NetDeviceContainer tmp4;
    tmp4.Add(d2.Get(1)); /* n1 */
    Ipv6InterfaceContainer iic2 = ipv6.AssignWithoutAddress(tmp4);
    iic2.Add(iicr2);

    /* radvd configuration */
    RadvdHelper radvdHelper;
    /* R interface (n0 - R) */
    radvdHelper.AddAnnouncedPrefix(iic1.GetInterfaceIndex(1), Ipv6Address("2001:ABCD::0"), 64);
    radvdHelper.AddAnnouncedPrefix(iic1.GetInterfaceIndex(1), Ipv6Address("2001:1::0"), 64);

    // Set some non-standard timers so the simulation is not taking ages
    Ptr<RadvdInterface> routerInterface = radvdHelper.GetRadvdInterface(iic1.GetInterfaceIndex(1));
    routerInterface->SetMaxRtrAdvInterval(2000);
    routerInterface->SetMinRtrAdvInterval(1000);
    RadvdInterface::RadvdPrefixList prefixList = routerInterface->GetPrefixes();
    for (auto iter = prefixList.begin(); iter != prefixList.end(); iter++)
    {
        (*iter)->SetPreferredLifeTime(3);
        (*iter)->SetValidLifeTime(5);
    }

    /* R interface (R - n1) */
    radvdHelper.AddAnnouncedPrefix(iic2.GetInterfaceIndex(1), Ipv6Address("2001:2::0"), 64);

    // Set some non-standard timers so the simulation is not taking ages
    routerInterface = radvdHelper.GetRadvdInterface(iic2.GetInterfaceIndex(1));
    routerInterface->SetMaxRtrAdvInterval(2000);
    routerInterface->SetMinRtrAdvInterval(1000);
    prefixList = routerInterface->GetPrefixes();
    for (auto iter = prefixList.begin(); iter != prefixList.end(); iter++)
    {
        (*iter)->SetPreferredLifeTime(3);
        (*iter)->SetValidLifeTime(5);
    }

    ApplicationContainer radvdApps = radvdHelper.Install(r);
    radvdApps.Start(Seconds(1));
    radvdApps.Stop(Seconds(2));

    /* Create a Ping application to send ICMPv6 echo request from n0 to n1 via R */
    uint32_t packetSize = 1024;
    uint32_t maxPacketCount = 8;
    PingHelper ping(
        Ipv6Address("2001:2::200:ff:fe00:4")); /* should be n1 address after autoconfiguration */
    // ping.SetIfIndex(iic1.GetInterfaceIndex(0));

    ping.SetAttribute("Count", UintegerValue(maxPacketCount));
    ping.SetAttribute("Size", UintegerValue(packetSize));
    ApplicationContainer apps = ping.Install(net1.Get(0));
    apps.Start(Seconds(2));
    apps.Stop(Seconds(5));

    Ptr<OutputStreamWrapper> routingStream = Create<OutputStreamWrapper>(&std::cout);
    Ipv6RoutingHelper::PrintRoutingTableAt(Seconds(2), n0, routingStream);
    Ipv6RoutingHelper::PrintRoutingTableAt(Seconds(10), n0, routingStream);

    IpAddressHelper ipAddressHelper;
    /* RA should be received, two prefixes + routes + default route should be present */
    Simulator::Schedule(Seconds(2), &IpAddressHelper::PrintIpAddresses, &ipAddressHelper, n0);
    /* at the end, RA addresses and routes should be cleared */
    Simulator::Schedule(Seconds(10), &IpAddressHelper::PrintIpAddresses, &ipAddressHelper, n0);

    AsciiTraceHelper ascii;
    csma.EnableAsciiAll(ascii.CreateFileStream("radvd-two-prefix.tr"));
    csma.EnablePcapAll(std::string("radvd-two-prefix"), true);

    NS_LOG_INFO("Run Simulation.");
    Simulator::Run();
    Simulator::Destroy();
    NS_LOG_INFO("Done.");

    return 0;
}
