/*
 * (c) Copyright 2020 CORSIKA Project, corsika-project@lists.kit.edu
 *
 * This software is distributed under the terms of the GNU General Public
 * Licence version 3 (GPL Version 3). See file LICENSE for a full version of
 * the license.
 */
#include <catch2/catch.hpp>

#include <corsika/modules/radio/ZHS.hpp>
//#include <corsika/modules/radio/CoREAS.hpp>
#include <corsika/modules/radio/antennas/TimeDomainAntenna.hpp>
#include <corsika/modules/radio/detectors/RadioDetector.hpp>
#include <corsika/modules/radio/propagators/StraightPropagator.hpp>
#include <corsika/modules/radio/propagators/SignalPath.hpp>
#include <corsika/modules/radio/propagators/RadioPropagator.hpp>

#include <vector>
#include <xtensor/xtensor.hpp>
#include <xtensor/xbuilder.hpp>
#include <xtensor/xio.hpp>
#include <xtensor/xcsv.hpp>
#include <istream>
#include <fstream>
#include <iostream>


#include <corsika/media/Environment.hpp>
#include <corsika/media/HomogeneousMedium.hpp>
#include <corsika/media/IMediumModel.hpp>
#include <corsika/media/IRefractiveIndexModel.hpp>
#include <corsika/media/LayeredSphericalAtmosphereBuilder.hpp>
#include <corsika/media/UniformRefractiveIndex.hpp>
#include <corsika/media/ExponentialRefractiveIndex.hpp>
#include <corsika/media/VolumeTreeNode.hpp>
#include <corsika/framework/geometry/CoordinateSystem.hpp>
#include <corsika/framework/geometry/Line.hpp>
#include <corsika/framework/geometry/Point.hpp>
#include <corsika/framework/geometry/RootCoordinateSystem.hpp>
#include <corsika/framework/geometry/Vector.hpp>
#include <corsika/setup/SetupStack.hpp>
#include <corsika/setup/SetupTrajectory.hpp>
#include <corsika/framework/core/PhysicalUnits.hpp>
#include <corsika/framework/core/PhysicalConstants.hpp>

using namespace corsika;

double constexpr absMargin = 1.0e-7;

TEST_CASE("Radio", "[processes]") {

  logging::set_level(logging::level::info);
  corsika_logger->set_pattern("[%n:%^%-8l%$] custom pattern: %v");


  // check that I can create and reset a TimeDomain process
//  SECTION("TimeDomainDetector") {
//
//    // construct a time domain detector
//    AntennaCollection<TimeDomainAntenna> detector;
//
//    //   // and construct some time domain radio process
//    //   TimeDomain<ZHS<>, TimeDomainDetector<TimeDomainAntenna>> process(detector);
//    //   TimeDomain<ZHS<CPU>, TimeDomainDetector<TimeDomainAntenna>> process2(detector);
//    //   TimeDomain<ZHS<CPU>, decltype(detector)> process3(detector);
//  }

  // check that I can create time domain antennas
  SECTION("TimeDomainAntenna") {

    // create an environment so we can get a coordinate system
    Environment<IMediumModel> env;

    // the antenna location
    const auto point1{Point(env.getCoordinateSystem(), 1_m, 2_m, 3_m)};
    const auto point2{Point(env.getCoordinateSystem(), 4_m, 5_m, 6_m)};

    // create times for the antenna
    const TimeType t1{10_s};
    const TimeType t2{10_s};
    const InverseTimeType t3{1/1_s};

    // check that I can create an antenna at (1, 2, 3)
    TimeDomainAntenna ant1("antenna_name", point1, t1, t2, t3);
    TimeDomainAntenna ant2("antenna_name2", point2, 11_s, t2, t3);

    // assert that the antenna name is correct
    REQUIRE(ant1.getName() == "antenna_name");

    // and check that the antenna is at the right location
    REQUIRE((ant1.getLocation() - point1).getNorm() < 1e-12 * 1_m);

    // construct a radio detector instance to store our antennas
    AntennaCollection<TimeDomainAntenna> detector;

    // add this antenna to the process
    detector.addAntenna(ant1);
    detector.addAntenna(ant2);

    // create an environment with uniform refractive index of 1
    using UniRIndex =
    UniformRefractiveIndex<HomogeneousMedium<IRefractiveIndexModel<IMediumModel>>>;

    using EnvType = Environment<IRefractiveIndexModel<IMediumModel>>;
    EnvType env6;

    // get a coordinate system
    const CoordinateSystemPtr rootCS6 = env6.getCoordinateSystem();

    auto Medium6 = EnvType::createNode<Sphere>(
        Point{rootCS6, 0_m, 0_m, 0_m}, 1_km * std::numeric_limits<double>::infinity());

    auto const props6 = Medium6->setModelProperties<UniRIndex>(
        1, 1_kg / (1_m * 1_m * 1_m),
        NuclearComposition(
            std::vector<Code>{Code::Nitrogen},
            std::vector<float>{1.f}));

    env6.getUniverse()->addChild(std::move(Medium6));


    // get a unit vector
    Vector<dimensionless_d> v1(rootCS6, {0, 0, 1});
    QuantityVector<ElectricFieldType::dimension_type> v11{10_V / 1_m, 10_V / 1_m, 10_V / 1_m};

    Vector<dimensionless_d> v2(rootCS6, {0, 1, 0});
    QuantityVector<ElectricFieldType::dimension_type> v22{20_V / 1_m, 20_V / 1_m, 20_V / 1_m};

    // use receive methods
    ant1.receive(15_s, v1, v11);
    ant2.receive(16_s, v2, v22);

    // use getWaveform() method
    auto [t11, E1] = ant1.getWaveform();
    CHECK(E1(5,0) - 10 == 0);

    auto [t222, E2] = ant2.getWaveform();
    CHECK(E2(5,0) -20 == 0);


    // the rest is just random ideas
    //////////////////////////////////////////////////////////////////////////////////////

//    for (auto& kostas : detector.getAntennas()) {
//      std::cout << kostas.getName() << std::endl;
//      kostas.receive(15_s, v1, v11);
//      std::cout << kostas.waveformE_;
//      auto [t, E] = kostas.getWaveform();
//      std::cout << E(5,0) << std::endl;
//      kostas.receive(16_s, v2, v22);
//      std::cout << E(5,0) << std::endl;
//    }



    //    auto t33{static_cast<int>(t1 / t2)};
//    std::cout << t33 << std::endl;
//    xt::xtensor<double,2> waveformE_ = xt::zeros<double>({2, 3});
//    xt::xtensor<double,2> res = xt::view(waveformE_);
//    std::cout << ant1.waveformE_ << std::endl;
//    std::cout << " " << std::endl;
//    std::cout << ant2.waveformE_ << std::endl;
//    std::cout << " " << std::endl;
//    std::cout << ant1.times_ << std::endl;
//    std::cout << " " << std::endl;
//    std::cout << ant2.times_ << std::endl;
//   auto [t, E] = ant2.getWaveform();
//

//
//
//   std::ofstream out_file("antenna_output.csv");
//    xt::dump_csv(out_file, t);
//    xt::dump_csv(out_file, E);
//    out_file.close();


//    for (auto& antenna : detector.getAntennas()) {
//      auto [t, E] = antenna.getWaveform();
//    }

//    int i = 1;
//    auto x = detector.getAntennas();
//    for (auto& antenna : x) {
//
//      auto [t, E] = antenna.getWaveform();
//      std::ofstream out_file("antenna" + to_string(i) + "_output.csv");
//      std::cout << E(5,0) << std::endl;
//      xt::dump_csv(out_file, t);
//      xt::dump_csv(out_file, E);
//      out_file.close();
//      ++i;
//    }


//    detector.writeOutput();
//    ant1.reset();
//    ant2.reset();
//
//    std::cout << ant1.waveformE_ << std::endl;
//    std::cout << ant2.waveformE_ << std::endl;

    //////////////////////////////////////////////////////////////////////////////////////
  }

  // check that I can create working Straight Propagators in different environments
  SECTION("Straight Propagator w/ Uniform Refractive Index") {

    // create an environment with uniform refractive index of 1
    using UniRIndex =
        UniformRefractiveIndex<HomogeneousMedium<IRefractiveIndexModel<IMediumModel>>>;

    using EnvType = Environment<IRefractiveIndexModel<IMediumModel>>;
    EnvType env;

    // get a coordinate system
    const CoordinateSystemPtr rootCS = env.getCoordinateSystem();

    auto Medium = EnvType::createNode<Sphere>(
        Point{rootCS, 0_m, 0_m, 0_m}, 1_km * std::numeric_limits<double>::infinity());

    auto const props = Medium->setModelProperties<UniRIndex>(
        1, 1_kg / (1_m * 1_m * 1_m),
        NuclearComposition(
            std::vector<Code>{Code::Nitrogen},
            std::vector<float>{1.f}));

    env.getUniverse()->addChild(std::move(Medium));

    // get some points
    Point p0(rootCS, {0_m, 0_m, 0_m});
    //    Point p1(rootCS, {0_m, 0_m, 1_m});
    //    Point p2(rootCS, {0_m, 0_m, 2_m});
    //    Point p3(rootCS, {0_m, 0_m, 3_m});
    //    Point p4(rootCS, {0_m, 0_m, 4_m});
    //    Point p5(rootCS, {0_m, 0_m, 5_m});
    //    Point p6(rootCS, {0_m, 0_m, 6_m});
    //    Point p7(rootCS, {0_m, 0_m, 7_m});
    //    Point p8(rootCS, {0_m, 0_m, 8_m});
    //    Point p9(rootCS, {0_m, 0_m, 9_m});
    Point p10(rootCS, {0_m, 0_m, 10_m});

    // get a unit vector
    Vector<dimensionless_d> v1(rootCS, {0, 0, 1});

    //    // get a geometrical path of points
    //    Path P1({p0,p1,p2,p3,p4,p5,p6,p7,p8,p9,p10});

    // construct a Straight Propagator given the uniform refractive index environment
    StraightPropagator SP(env);

    // store the outcome of the Propagate method to paths_
    auto const paths_ = SP.propagate(p0, p10, 1_m);

    // perform checks to paths_ components
    for (auto const& path : paths_) {
      CHECK((path.total_time_ / 1_s) - ((34_m / (3 * constants::c)) / 1_s) ==
            Approx(0).margin(absMargin));
      CHECK(path.average_refractive_index_ == Approx(1));
      CHECK(path.emit_.getComponents() == v1.getComponents());
      CHECK(path.receive_.getComponents() == v1.getComponents());
      CHECK(path.R_distance_ == 10_m);
      //      CHECK(std::equal(P1.begin(), P1.end(), path.points_.begin(),[]
      //      (Point a, Point b) { return (a - b).norm() / 1_m < 1e-5;}));
      //TODO:THINK ABOUT THE POINTS IN THE SIGNALPATH.H
    }

    CHECK(paths_.size() == 1);
  }

    SECTION("Straight Propagator w/ Exponential Refractive Index") {

//    logging::set_level(logging::level::info);
//    corsika_logger->set_pattern("[%n:%^%-8l%$] custom pattern: %v");

     // create an environment with exponential refractive index (n_0 = 1 & lambda = 0)
    using ExpoRIndex = ExponentialRefractiveIndex<HomogeneousMedium
        <IRefractiveIndexModel<IMediumModel>>>;

    using EnvType = Environment<IRefractiveIndexModel<IMediumModel>>;
    EnvType env1;

    //get another coordinate system
    const CoordinateSystemPtr rootCS1 = env1.getCoordinateSystem();

    auto Medium1 = EnvType::createNode<Sphere>(
        Point{rootCS1, 0_m, 0_m, 0_m}, 1_km * std::numeric_limits<double>::infinity());

    auto const props1 =
        Medium1
            ->setModelProperties<ExpoRIndex>( 1, 0 / 1_m,
               1_kg / (1_m * 1_m * 1_m),
               NuclearComposition(
               std::vector<Code>{Code::Nitrogen},
               std::vector<float>{1.f}));

    env1.getUniverse()->addChild(std::move(Medium1));

    // get some points
    Point pp0(rootCS1, {0_m, 0_m, 0_m});
//    Point pp1(rootCS1, {0_m, 0_m, 1_m});
//    Point pp2(rootCS1, {0_m, 0_m, 2_m});
//    Point pp3(rootCS1, {0_m, 0_m, 3_m});
//    Point pp4(rootCS1, {0_m, 0_m, 4_m});
//    Point pp5(rootCS1, {0_m, 0_m, 5_m});
//    Point pp6(rootCS1, {0_m, 0_m, 6_m});
//    Point pp7(rootCS1, {0_m, 0_m, 7_m});
//    Point pp8(rootCS1, {0_m, 0_m, 8_m});
//    Point pp9(rootCS1, {0_m, 0_m, 9_m});
    Point pp10(rootCS1, {0_m, 0_m, 10_m});

    // get a unit vector
    Vector<dimensionless_d> vv1(rootCS1, {0, 0, 1});

    // construct a Straight Propagator given the exponential refractive index environment
    StraightPropagator SP1(env1);

    // store the outcome of Propagate method to paths1_
    auto const paths1_ = SP1.propagate(pp0, pp10, 1_m);

    // perform checks to paths1_ components (this is just a sketch for now)
    for (auto const& path :paths1_) {
      CHECK( (path.total_time_ / 1_s)  - ((34_m / (3 * constants::c)) / 1_s)
             == Approx(0).margin(absMargin) );
      CHECK( path.average_refractive_index_ == Approx(1) );
      CHECK( path.emit_.getComponents() == vv1.getComponents() );
      CHECK( path.receive_.getComponents() == vv1.getComponents() );
      CHECK( path.R_distance_ == 10_m );
    }

    CHECK( paths1_.size() == 1 );

    /*
    * A second environment with another exponential refractive index
    */

    // create an environment with exponential refractive index (n_0 = 2 & lambda = 2)
    using ExpoRIndex = ExponentialRefractiveIndex<HomogeneousMedium
        <IRefractiveIndexModel<IMediumModel>>>;

    using EnvType = Environment<IRefractiveIndexModel<IMediumModel>>;
    EnvType env2;

    //get another coordinate system
    const CoordinateSystemPtr rootCS2 = env2.getCoordinateSystem();

    auto Medium2 = EnvType::createNode<Sphere>(
        Point{rootCS2, 0_m, 0_m, 0_m}, 1_km * std::numeric_limits<double>::infinity());

    auto const props2 =
        Medium2
            ->setModelProperties<ExpoRIndex>( 2, 2 / 1_m,
                                              1_kg / (1_m * 1_m * 1_m),
                                              NuclearComposition(
                                                  std::vector<Code>{Code::Nitrogen},
                                                  std::vector<float>{1.f}));

    env2.getUniverse()->addChild(std::move(Medium2));

    // get some points
    Point ppp0(rootCS2, {0_m, 0_m, 0_m});
    Point ppp10(rootCS2, {0_m, 0_m, 10_m});

    // get a unit vector
    Vector<dimensionless_d> vvv1(rootCS2, {0, 0, 1});

    // construct a Straight Propagator given the exponential refractive index environment
    StraightPropagator SP2(env2);

    // store the outcome of Propagate method to paths1_
    auto const paths2_ = SP2.propagate(ppp0, ppp10, 1_m);

    // perform checks to paths1_ components (this is just a sketch for now)
    for (auto const& path :paths2_) {
      CHECK( (path.total_time_ / 1_s)  - ((3.177511688_m / (3 * constants::c)) / 1_s)
             == Approx(0).margin(absMargin) );
      CHECK( path.average_refractive_index_ == Approx(0.210275935) );
      CHECK( path.emit_.getComponents() == vvv1.getComponents() );
      CHECK( path.receive_.getComponents() == vvv1.getComponents() );
      CHECK( path.R_distance_ == 10_m );
    }

    CHECK( paths2_.size() == 1 );

    }

//    SECTION("Construct a ZHS process.") {
//
//        // TODO: construct the environment for the propagator

    //////////////////////////////////////////////////////////////////////////////////////
//    // useful information
//  // create an environment so we can get a coordinate system
//  environment::Environment<environment::IMediumModel> env;
//
//  // the antenna location
//  const auto point{geometry::Point(env.GetCoordinateSystem(), 1_m, 2_m, 3_m)};
//
//  // check that I can create an antenna at (1, 2, 3)
//  const auto ant{TimeDomainAntenna("antenna_name", point)};
//
//  // assert that the antenna name is correct
//  REQUIRE(ant.GetName() == "antenna_name");
//
//  // and check that the antenna is at the right location
//  REQUIRE((ant.GetLocation() - point).norm() < 1e-12 * 1_m);
//
//  // construct a radio detector instance to store our antennas
//  TimeDomainDetector<TimeDomainAntenna> detector;
//
//  // add this antenna to the process
//  detector.AddAntenna(ant);
//
//  // create a TimeDomain process
//  auto zhs{TimeDomain<ZHS<CPU>, decltype(detector)>(detector)};
//
//  // get the antenna back from the process and check the properties
//  REQUIRE(detector.GetAntennas().cbegin()->GetName() == "antenna_name");
//
//  // and check the location is the same
//  REQUIRE((detector.GetAntennas().cbegin()->GetLocation() - point).norm() <
//          1e-12 * 1_m);
//
//  // and ANOTHER antenna
//  const auto ant2{TimeDomainAntenna("antenna_name", point)};
//  detector.AddAntenna(ant2);
//  // and check that the number of antennas visible to the process has increased
//  REQUIRE(zhs.GetDetector().GetAntennas().size() == 2);

//////////////////////////////////////////////////////////////////////////////////////////

//  using VelocityVec = Vector<corsika::units::si::SpeedType::dimension_type>;
//
//  // setup environment, geometry
//  environment::Environment<environment::IMediumModel> env;
//
//  // and get the coordinate systm
//  geometry::CoordinateSystem const& cs{env.GetCoordinateSystem()};
//
//  // a test particle
//  const auto pcode{particles::Code::Electron};
//  const auto mass{particles::Electron::GetMass()};
//
//  // create a new stack for each trial
//  setup::Stack stack;
//
//  // construct an energy
//  const HEPEnergyType E0{1_TeV};
//
//  // compute the necessary momentumn
//  const HEPMomentumType P0{sqrt(E0 * E0 - mass * mass)};
//
//  // and create the momentum vector
//  const auto plab{corsika::stack::MomentumVector(cs, {0_GeV, 0_GeV, P0})};
//
//  // and create the location of the particle in this coordinate system
//  const geometry::Point pos(cs, 5_m, 1_m, 8_m);
//
//  // add the particle to the stack
//  auto particle{stack.AddParticle(std::make_tuple(pcode, E0, plab, pos, 0_ns))};
//
//  // get a view into the stack
//  corsika::stack::SecondaryView stackview(particle);
//
//  // create a trajectory
//  const auto& track{
//      Trajectory(Line(pos, VelocityVec(cs, 0_m / 1_s, 0_m / 1_s, 0.1_m / 1_ns)), 1_ns)};
//
//  // and create a view vector
//  const auto& view{Vector(cs, 0_m, 0_m, 1_m)};
//
//  // construct a radio detector instance to store our antennas
//  TimeDomainDetector<TimeDomainAntenna> detector;
//
//  // the antenna location
//  const auto point{geometry::Point(cs, 1_m, 2_m, 3_m)};
//
//  // check that I can create an antenna at (1, 2, 3)
//  const auto ant{TimeDomainAntenna("antenna_name", point)};
//
//  // add this antenna to the process
//  detector.AddAntenna(ant);
//
//  // create a TimeDomain process
//  auto zhs{TimeDomain<ZHS<CPU>, decltype(detector)>(detector)};
//
//  // get the projectile
//  auto projectile{stackview.GetProjectile()};
//
//  // call ZHS over the track
//  zhs.DoContinuous(projectile, track);
//  zhs.Simulate(projectile, track);
//
//  // try and call the ZHS implementation directly for a given view direction
//  ZHS<CPU>::Emit(projectile, track, view);

//////////////////////////////////////////////////////////////////////////////////////////


  // create an environment with uniform refractive index of 1
//  using UniRIndex =
//  UniformRefractiveIndex<HomogeneousMedium<IRefractiveIndexModel<IMediumModel>>>;
//  using EnvType = Environment<IRefractiveIndexModel<IMediumModel>>;
//
//  EnvType env;
//
//  // get a coordinate system
//  const CoordinateSystemPtr rootCS = env.getCoordinateSystem();
//
//  auto Medium = EnvType::createNode<Sphere>(
//      Point{rootCS, 0_m, 0_m, 0_m}, 1_km * std::numeric_limits<double>::infinity());
//
//  auto const props = Medium->setModelProperties<UniRIndex>(
//      1, 1_kg / (1_m * 1_m * 1_m),
//      NuclearComposition(
//          std::vector<Code>{Code::Nitrogen},
//          std::vector<float>{1.f}));
//
//  env.getUniverse()->addChild(std::move(Medium));
//
//        // here we just use a deque to store the antenna
//        std::deque<TimeDomainAntenna> antennas;
//
//        // TODO: add time domain antennas to the deque
//
//        // and now create ZHS with this antenna collection
//        // and with a straight propagator
//        ZHS<decltype(antennas), StraightPropagator> zhs(antennas, env);
//        // TODO: do we need the explicit type declaration?
//
//        // here is where the simulation happens
//
//        // and call zhs.writeOutput() at the end.
//    }

} // END: TEST_CASE("Radio", "[processes]")