/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2013-2026 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.

    OpenFOAM 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.

    OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.

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

#include "gaussConvectionScheme.H"
#include "blendedSchemeBase.H"
#include "fvcCellReduce.H"

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

template<class Type>
bool Foam::functionObjects::blendingFactor::calcBF()
{
    if (!foundObject<VolField<Type>>(fieldName_))
    {
        return false;
    }

    const VolField<Type>& field = lookupObject<VolField<Type>>(fieldName_);

    const word divScheme(word("div(", phiName_, ',', fieldName_, ')'));
    ITstream& its = mesh_.schemes().div(divScheme);

    const surfaceScalarField& phi = lookupObject<surfaceScalarField>(phiName_);

    tmp<fv::convectionScheme<Type>> cs =
        fv::convectionScheme<Type>::New(mesh_, phi, its);

    const fv::gaussConvectionScheme<Type>& gcs =
        refCast<const fv::gaussConvectionScheme<Type>>(cs());

    const surfaceInterpolationScheme<Type>& interpScheme =
        gcs.interpScheme();

    if (!isA<blendedSchemeBase<Type>>(interpScheme))
    {
        FatalErrorInFunction
            << interpScheme.typeName << " is not a blended scheme"
            << exit(FatalError);
    }

    // Retrieve the face-based blending factor
    const blendedSchemeBase<Type>& blendedScheme =
        refCast<const blendedSchemeBase<Type>>(interpScheme);
    tmp<surfaceScalarField> factorf(blendedScheme.blendingFactor(field));

    // Convert into vol field whose values represent the local face maxima
    store
    (
        resultName_,
        fvc::cellReduce(factorf, maxEqOp())
    );

    return true;
}


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