/*
 * Copyright (c) 2021 NITK Surathkal
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * This example is inspired from examples/tutorial/third.cc by
 * substituting the CSMA network with another WiFi network.
 *
 * Author: Ameya Deshpande <ameyanrd@outlook.com>
 */

#include "ns3/applications-module.h"
#include "ns3/core-module.h"
#include "ns3/csma-module.h"
#include "ns3/internet-module.h"
#include "ns3/mobility-module.h"
#include "ns3/network-module.h"
#include "ns3/nix-vector-routing-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/ssid.h"
#include "ns3/wifi-module.h"

/**
 * This example demonstrates how Nix works with
 * two Wifi networks on the same channel.
 *
 * IPv4 Network Topology
 * \verbatim
    Wifi 10.1.1.0/24
                   AP
    *    *    *    *
    |    |    |    |   10.1.2.0/24
   n5   n6   n7   n0 -------------- n1   n2   n3   n4
                     point-to-point  |    |    |    |
                                     *    *    *    *
                                    AP
                                      Wifi 10.1.3.0/24
   \endverbatim
 *
 * \verbatim
    Wifi 2001:1::/64
                   AP
    *    *    *    *
    |    |    |    |   2001:2::/64
   n5   n6   n7   n0 -------------- n1   n2   n3   n4
                     point-to-point  |    |    |    |
                                     *    *    *    *
                                    AP
                                      Wifi 2001:3::/64
   \endverbatim
 *
 * Expected Outputs:
 * IPv4:
 * \verbatim
   Time: +7s, Nix Routing
   Route path from Node 4 to Node 7, Nix Vector: 100011 (6 bits left)
   10.1.1.3                 (Node 4)  ---->   10.1.1.4                 (Node 0)
   10.1.2.1                 (Node 0)  ---->   10.1.2.2                 (Node 1)
   10.1.3.4                 (Node 1)  ---->   10.1.3.3                 (Node 7)
   \endverbatim
 *
 * IPv6:
 * \verbatim
   Time: +7s, Nix Routing
   Route path from Node 4 to Node 7, Nix Vector: 100011 (6 bits left)
   2001:1::200:ff:fe00:5    (Node 4)  ---->   fe80::200:ff:fe00:6      (Node 0)
   fe80::200:ff:fe00:1      (Node 0)  ---->   fe80::200:ff:fe00:2      (Node 1)
   fe80::200:ff:fe00:a      (Node 1)  ---->   2001:3::200:ff:fe00:9    (Node 7)
   \endverbatim
 */

using namespace ns3;

NS_LOG_COMPONENT_DEFINE("NixDoubleWifiExample");

int
main(int argc, char* argv[])
{
    bool useIpv6 = false;
    bool enableNixLog = false;

    CommandLine cmd(__FILE__);
    cmd.AddValue("useIPv6", "Use IPv6 instead of IPv4", useIpv6);
    cmd.AddValue("enableNixLog", "Enable NixVectorRouting logging", enableNixLog);
    cmd.Parse(argc, argv);

    LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_INFO);
    LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
    if (enableNixLog)
    {
        LogComponentEnable("NixVectorRouting", LOG_LEVEL_LOGIC);
    }

    NodeContainer p2pNodes;
    p2pNodes.Create(2);

    PointToPointHelper pointToPoint;
    pointToPoint.SetDeviceAttribute("DataRate", StringValue("5Mbps"));
    pointToPoint.SetChannelAttribute("Delay", StringValue("2ms"));

    NetDeviceContainer p2pDevices;
    p2pDevices = pointToPoint.Install(p2pNodes);

    NodeContainer wifiStaNodes1;
    wifiStaNodes1.Create(3);
    NodeContainer wifiApNode1 = p2pNodes.Get(0);

    NodeContainer wifiStaNodes2;
    wifiStaNodes2.Create(3);
    NodeContainer wifiApNode2 = p2pNodes.Get(1);

    YansWifiChannelHelper channel = YansWifiChannelHelper::Default();
    YansWifiPhyHelper phy;
    phy.SetChannel(channel.Create());

    WifiHelper wifi;

    WifiMacHelper mac;
    Ssid ssid = Ssid("ns-3-ssid-first");
    mac.SetType("ns3::StaWifiMac", "Ssid", SsidValue(ssid), "ActiveProbing", BooleanValue(false));

    NetDeviceContainer staDevices1;
    staDevices1 = wifi.Install(phy, mac, wifiStaNodes1);

    mac.SetType("ns3::ApWifiMac", "Ssid", SsidValue(ssid));

    NetDeviceContainer apDevices1;
    apDevices1 = wifi.Install(phy, mac, wifiApNode1);

    ssid = Ssid("ns-3-ssid-second");
    mac.SetType("ns3::StaWifiMac", "Ssid", SsidValue(ssid), "ActiveProbing", BooleanValue(false));

    NetDeviceContainer staDevices2;
    staDevices2 = wifi.Install(phy, mac, wifiStaNodes2);

    mac.SetType("ns3::ApWifiMac", "Ssid", SsidValue(ssid));

    NetDeviceContainer apDevices2;
    apDevices2 = wifi.Install(phy, mac, wifiApNode2);

    MobilityHelper mobility;

    mobility.SetPositionAllocator("ns3::GridPositionAllocator",
                                  "MinX",
                                  DoubleValue(0.0),
                                  "MinY",
                                  DoubleValue(0.0),
                                  "DeltaX",
                                  DoubleValue(5.0),
                                  "DeltaY",
                                  DoubleValue(10.0),
                                  "GridWidth",
                                  UintegerValue(3),
                                  "LayoutType",
                                  StringValue("RowFirst"));

    mobility.SetMobilityModel("ns3::RandomWalk2dMobilityModel",
                              "Bounds",
                              RectangleValue(Rectangle(-50, 50, -50, 50)));
    mobility.Install(wifiStaNodes1);
    mobility.Install(wifiStaNodes2);

    mobility.SetMobilityModel("ns3::ConstantPositionMobilityModel");
    mobility.Install(wifiApNode1);
    mobility.Install(wifiApNode2);

    Address udpServerAddress;

    if (!useIpv6)
    {
        InternetStackHelper stack;
        Ipv4NixVectorHelper nixRouting;
        stack.SetRoutingHelper(nixRouting);
        stack.Install(wifiApNode1);
        stack.Install(wifiStaNodes1);
        stack.Install(wifiApNode2);
        stack.Install(wifiStaNodes2);

        Ipv4AddressHelper address;

        address.SetBase("10.1.1.0", "255.255.255.0");
        address.Assign(staDevices1);
        address.Assign(apDevices1);

        address.SetBase("10.1.2.0", "255.255.255.0");
        Ipv4InterfaceContainer p2pInterfaces;
        p2pInterfaces = address.Assign(p2pDevices);

        address.SetBase("10.1.3.0", "255.255.255.0");
        Ipv4InterfaceContainer staDevicesInterfaces2;
        staDevicesInterfaces2 = address.Assign(staDevices2);
        address.Assign(apDevices2);

        udpServerAddress = staDevicesInterfaces2.GetAddress(2);

        Ptr<OutputStreamWrapper> routingStream =
            Create<OutputStreamWrapper>("nix-double-wifi-ipv4.routes", std::ios::out);
        nixRouting.PrintRoutingPathAt(Seconds(7),
                                      wifiStaNodes1.Get(2),
                                      staDevicesInterfaces2.GetAddress(2),
                                      routingStream);
    }
    else
    {
        InternetStackHelper stack;
        Ipv6NixVectorHelper nixRouting;
        stack.SetRoutingHelper(nixRouting);
        stack.Install(wifiApNode1);
        stack.Install(wifiStaNodes1);
        stack.Install(wifiApNode2);
        stack.Install(wifiStaNodes2);

        Ipv6AddressHelper address;

        address.SetBase(Ipv6Address("2001:1::"), Ipv6Prefix(64));
        address.Assign(staDevices1);
        address.Assign(apDevices1);

        address.SetBase(Ipv6Address("2001:2::"), Ipv6Prefix(64));
        Ipv6InterfaceContainer p2pInterfaces;
        p2pInterfaces = address.Assign(p2pDevices);

        address.SetBase(Ipv6Address("2001:3::"), Ipv6Prefix(64));
        Ipv6InterfaceContainer staDevicesInterfaces2;
        staDevicesInterfaces2 = address.Assign(staDevices2);
        address.Assign(apDevices2);

        udpServerAddress = staDevicesInterfaces2.GetAddress(2, 1);

        Ptr<OutputStreamWrapper> routingStream =
            Create<OutputStreamWrapper>("nix-double-wifi-ipv6.routes", std::ios::out);
        nixRouting.PrintRoutingPathAt(Seconds(7),
                                      wifiStaNodes1.Get(2),
                                      staDevicesInterfaces2.GetAddress(2, 1),
                                      routingStream);
    }

    UdpEchoServerHelper echoServer(9);

    ApplicationContainer serverApps = echoServer.Install(wifiStaNodes2.Get(2));
    serverApps.Start(Seconds(1.0));
    serverApps.Stop(Seconds(10.0));

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

    ApplicationContainer clientApps = echoClient.Install(wifiStaNodes1.Get(2));
    clientApps.Start(Seconds(2.0));
    clientApps.Stop(Seconds(10.0));

    Simulator::Stop(Seconds(10.0));

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