/*---------------------------------------------------------------------------*\
  ==  == ====== ====   ====    |
                    \\     ||  | Multiphase Code Repository by HZDR
  ======   //   ||  || ===//   | Website: https://doi.org/10.14278/rodare.767
  ||  ||  //    ||  // || \\   | License: GPL-3.0-or-later
  ==  == ====== ====   ==  ==  |
-------------------------------------------------------------------------------
License
    This file is part of the Multiphase Code Repository by HZDR.

    Copyright (C) 2025 by Helmholtz-Zentrum Dresden-Rossendorf e.V. (HZDR),
    Website: https://hzdr.de

    Multiphase Code Repository by HZDR is based on the free software for
    computational fluid dynamics (CFD) from the OpenFOAM Foundation.
    Copyright (C) 2025 by OpenFOAM Foundation, Website: https://openfoam.org

    If you are interested in which files are original OpenFOAM Foundation
    files, which OpenFOAM Foundation files were modified, and which files were
    newly created, see FILES.md.

    Multiphase Code Repository by HZDR 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 3 of the
    License, or (at your option) any later version.

    Multiphase Code Repository by HZDR 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 the Multiphase Code Repository by HZDR. If not, see
    <http://www.gnu.org/licenses/>.

\*---------------------------------------------------------------------------*/

#include "growthGroupFractionFvScalarFieldSource.H"
#include "populationBalanceModel.H"

// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //

Foam::tmp<Foam::DimensionedField<Foam::scalar, Foam::volMesh>>
Foam::growthGroupFractionFvScalarFieldSource::w
(
    const fvSource& model,
    const label i
) const
{
    const populationBalanceModel& popBal = this->popBal();

    // Get the moment
    const label q = this->q();

    // Name of the weight normalisation field
    const word wName = popBal.phases()[i].name() + ":" + model.name() + ":w";

    // Quick return for volume moments that do not need to compute a weight
    if (q == 3)
    {
        return
            DimensionedField<scalar, volMesh>::New
            (
                wName,
                internalField().mesh(),
                popBal.v(i)
            );
    }

    // Create the weight normalisation field if it does not yet exist
    const bool haveW = db().foundObject<volScalarField::Internal>(wName);
    if (!haveW)
    {
        volScalarField::Internal* wPtr =
            new volScalarField::Internal
            (
                IOobject
                (
                    wName,
                    internalField().mesh().time().name(),
                    internalField().mesh()
                ),
                internalField().mesh(),
                pow(dimVolume, scalar(q)/3 - 1)
            );

        wPtr->store();
    }

    // Update the weight normalisation field if it is out of date
    volScalarField::Internal& w =
        db().lookupObjectRef<volScalarField::Internal>(wName);
    if (!haveW || !w.hasStoredOldTimes())
    {
        w.primitiveFieldRef() = scalar(0);

        for
        (
            label j = popBal.diameters()[i].iFirst();
            j <= popBal.diameters()[i].iLast();
            ++ j
        )
        {
            w.primitiveFieldRef() +=
                popBal.f(j)*pow(popBal.v(j), scalar(q)/3 - 1);
        }
    }

    // Return the normalised weight for this group
    return pow(popBal.v(i), scalar(q)/3)/w;
}


// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

Foam::growthGroupFractionFvScalarFieldSource::
growthGroupFractionFvScalarFieldSource
(
    const DimensionedField<scalar, volMesh>& iF,
    const dictionary& dict
)
:
    growthFvScalarFieldSource(iF, dict),
    groupPropertyFvScalarField(iF)
{}


Foam::growthGroupFractionFvScalarFieldSource::
growthGroupFractionFvScalarFieldSource
(
    const growthGroupFractionFvScalarFieldSource& field,
    const DimensionedField<scalar, volMesh>& iF
)
:
    growthFvScalarFieldSource(field, iF),
    groupPropertyFvScalarField(iF)
{}


// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //

Foam::tmp<Foam::DimensionedField<Foam::scalar, Foam::volMesh>>
Foam::growthGroupFractionFvScalarFieldSource::internalCoeff
(
    const fvSource& model,
    const DimensionedField<scalar, volMesh>& source
) const
{
    const populationBalanceModel& popBal = this->popBal();
    const label i = this->i();

    const dimensionedScalar& xi = popBal.v(i);
    const DimensionedField<scalar, volMesh> wi(w(model, i));

    tmp<DimensionedField<scalar, volMesh>> tinternalCoeff;

    if (i == 0)
    {
        tinternalCoeff = neg(source)*wi/xi;
    }
    else
    {
        const dimensionedScalar& xiMinus1 = popBal.v(i - 1);
        tinternalCoeff = neg(source)*wi/(xi - xiMinus1);
    }

    if (i != popBal.nGroups() - 1)
    {
        const dimensionedScalar& xiPlus1 = popBal.v(i + 1);
        tinternalCoeff.ref() -= pos(source)*wi/(xiPlus1 - xi);
    }
    else
    {
        tinternalCoeff.ref() += pos(source)*wi/xi;
    }

    return tinternalCoeff;
}


Foam::Pair<Foam::tmp<Foam::DimensionedField<Foam::scalar, Foam::volMesh>>>
Foam::growthGroupFractionFvScalarFieldSource::sourceCoeffs
(
    const fvSource& model
) const
{
    const populationBalanceModel& popBal = this->popBal();
    const label i = this->i();

    const dimensionedScalar& xi = popBal.v(i);

    Pair<tmp<DimensionedField<scalar, volMesh>>> tsourceCoeffs;

    if (i != 0)
    {
        const DimensionedField<scalar, volMesh>& fiMinus1 = popBal.f(i - 1);
        const dimensionedScalar& xiMinus1 = popBal.v(i - 1);
        tsourceCoeffs.first() =
            fiMinus1*w(model, i - 1)*(xi/xiMinus1)/(xi - xiMinus1);
    }

    if (i != popBal.nGroups() - 1)
    {
        const DimensionedField<scalar, volMesh>& fiPlus1 = popBal.f(i + 1);
        const dimensionedScalar& xiPlus1 = popBal.v(i + 1);
        tsourceCoeffs.second() =
            -fiPlus1*w(model, i + 1)*(xi/xiPlus1)/(xiPlus1 - xi);
    }

    return tsourceCoeffs;
}


Foam::tmp<Foam::DimensionedField<Foam::scalar, Foam::volMesh>>
Foam::growthGroupFractionFvScalarFieldSource::sourceCoeff
(
    const fvSource& model,
    const DimensionedField<scalar, volMesh>& source
) const
{
    const populationBalanceModel& popBal = this->popBal();
    const label i = this->i();

    Pair<tmp<DimensionedField<scalar, volMesh>>> tsourceCoeffs =
        sourceCoeffs(model);

    return
        i == popBal.diameters()[i].iFirst()
      ? neg(source)*tsourceCoeffs.second()
      : i == popBal.diameters()[i].iLast()
      ? pos(source)*tsourceCoeffs.first()
      : pos(source)*tsourceCoeffs.first()
      + neg(source)*tsourceCoeffs.second();
}


// ************************************************************************* //
