// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
// vi: set et ts=4 sw=4 sts=4:
/*
  This file is part of the Open Porous Media project (OPM).

  OPM is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 2 of the License, or
  (at your option) any later version.

  OPM is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with OPM.  If not, see <http://www.gnu.org/licenses/>.

  Consult the COPYING file in the top-level source directory of this
  module for the precise wording of the license and the list of
  copyright holders.
*/
/*!
 * \file
 *
 * \brief This is test for the ChiFlash flash solver.
 */
#include "config.h"

#include <opm/material/constraintsolvers/ChiFlash.hpp>
#include <opm/material/fluidsystems/chifluid/twophasefluidsystem.hh>

#include <opm/material/densead/Evaluation.hpp>
#include <opm/material/constraintsolvers/ComputeFromReferencePhase.hpp>
// #include <opm/material/constraintsolvers/NcpFlash.hpp>
#include <opm/material/fluidstates/CompositionalFluidState.hpp>
// #include <opm/material/fluidsystems/Spe5FluidSystem.hpp>
#include <opm/material/fluidmatrixinteractions/LinearMaterial.hpp>
// #include <opm/material/fluidmatrixinteractions/MaterialTraits.hpp>

#include <dune/common/parallel/mpihelper.hh>

void testChiFlash()
{
    using Scalar = double;
    using FluidSystem = Opm::TwoPhaseThreeComponentFluidSystem<Scalar>;

    constexpr auto numComponents = FluidSystem::numComponents;
    typedef Dune::FieldVector<Scalar, numComponents> ComponentVector;
    typedef Opm::CompositionalFluidState<Scalar, FluidSystem> FluidState;

    // From co2-compositional branch, it uses
    // typename FluidSystem::template ParameterCache<Evaluation> paramCache;
    typedef typename FluidSystem::template ParameterCache<Scalar> ParameterCache;
    using ComponentVector = Dune::FieldVector<Scalar, numComponents>;
    using Evaluation = Opm::DenseAd::Evaluation<double, numComponents>;


    FluidState fs;
    // TODO: no capillary pressure for now
    const Scalar p_init = 100.*1.e5; // 100 bar
    fs.setPressure(FluidSystem::oilPhaseIdx, p_init);
    fs.setPressure(FluidSystem::gasPhaseIdx, p_init);

    fs.setMoleFraction(FluidSystem::oilPhaseIdx, FluidSystem::Comp0Idx, MFCOMP0);
    fs.setMoleFraction(FluidSystem::oilPhaseIdx, FluidSystem::Comp1Idx, MFCOMP1);

    fs.setMoleFraction(FluidSystem::gasPhaseIdx, FluidSystem::Comp0Idx, MFCOMP0);
    fs.setMoleFraction(FluidSystem::gasPhaseIdx, FluidSystem::Comp1Idx, MFCOMP1);

    fs.setSaturation(FluidSystem::oilPhaseIdx, 1.0);
    fs.setSaturation(FluidSystem::gasPhaseIdx, 0.0);

    fs.setTemperature(303);

    ParameterCache paramCache;
    paramCache.updatePhase(fs, FluidSystem::oilPhaseIdx);
    paramCache.updatePhase(fs, FluidSystem::gasPhaseIdx);
    fs.setDensity(FluidSystem::oilPhaseIdx, FluidSystem::density(fs, paramCache, FluidSystem::oilPhaseIdx));
    fs.setDensity(FluidSystem::gasPhaseIdx, FluidSystem::density(fs, paramCache, FluidSystem::gasPhaseIdx));

    ComponentVector zInit(0.); // TODO; zInit needs to be normalized.
    const double flash_tolerance = 1.e-8;
    const int flash_verbosity = 1;
    const std::string flash_twophase_method = "ssi";

    // Set initial K and L
    for (unsigned compIdx = 0; compIdx < numComponents; ++compIdx) {
        const Scalar Ktmp = fs.wilsonK_(compIdx);
        fs.setKvalue(compIdx, Ktmp);
    }
    const Scalar Ltmp = -1.0;
    fs.setLvalue(Ltmp);

    const int spatialIdx = 0;
    using Flash = Opm::ChiFlash<double, Evaluation, FluidSystem>;
    Flash::solve(fs, zInit, spatialIdx, flash_verbosity, flash_twophase_method, flash_tolerance);

}

int main(int argc, char **argv)
{
    Dune::MPIHelper::instance(argc, argv);

    testChiFlash();

    return 0;
}