/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | www.openfoam.com
     \\/     M anipulation  |
-------------------------------------------------------------------------------
    Copyright (C) 2011-2016 OpenFOAM Foundation
    Copyright (C) 2016 OpenCFD Ltd.
-------------------------------------------------------------------------------
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 "velocityComponentLaplacianFvMotionSolver.H"
#include "motionInterpolation.H"
#include "motionDiffusivity.H"
#include "fvmLaplacian.H"
#include "addToRunTimeSelectionTable.H"
#include "fvOptions.H"

// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //

namespace Foam
{
    defineTypeNameAndDebug(velocityComponentLaplacianFvMotionSolver, 0);

    addToRunTimeSelectionTable
    (
        motionSolver,
        velocityComponentLaplacianFvMotionSolver,
        dictionary
    );
}


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

Foam::velocityComponentLaplacianFvMotionSolver::
velocityComponentLaplacianFvMotionSolver
(
    const polyMesh& mesh,
    const IOdictionary& dict
)
:
    componentVelocityMotionSolver(mesh, dict, typeName),
    fvMotionSolver(mesh),
    cellMotionU_
    (
        IOobject
        (
            "cellMotionU" + cmptName_,
            mesh.time().timeName(),
            mesh,
            IOobject::READ_IF_PRESENT,
            IOobject::AUTO_WRITE
        ),
        fvMesh_,
        dimensionedScalar(pointMotionU_.dimensions(), Zero),
        cellMotionBoundaryTypes<scalar>(pointMotionU_.boundaryField())
    ),
    interpolationPtr_
    (
        coeffDict().found("interpolation")
      ? motionInterpolation::New(fvMesh_, coeffDict().lookup("interpolation"))
      : motionInterpolation::New(fvMesh_)
    ),
    diffusivityPtr_
    (
        motionDiffusivity::New(fvMesh_, coeffDict().lookup("diffusivity"))
    )
{}


// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //

Foam::velocityComponentLaplacianFvMotionSolver::
~velocityComponentLaplacianFvMotionSolver()
{}


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

Foam::tmp<Foam::pointField>
Foam::velocityComponentLaplacianFvMotionSolver::curPoints() const
{
    interpolationPtr_->interpolate
    (
        cellMotionU_,
        pointMotionU_
    );

    tmp<pointField> tcurPoints(new pointField(fvMesh_.points()));

    tcurPoints.ref().replace
    (
        cmpt_,
        tcurPoints().component(cmpt_)
      + fvMesh_.time().deltaTValue()*pointMotionU_.primitiveField()
    );

    twoDCorrectPoints(tcurPoints.ref());

    return tcurPoints;
}


void Foam::velocityComponentLaplacianFvMotionSolver::solve()
{
    // The points have moved so before interpolation update
    // the fvMotionSolver accordingly
    movePoints(fvMesh_.points());

    diffusivityPtr_->correct();
    pointMotionU_.boundaryFieldRef().updateCoeffs();

    fv::options& fvOptions(fv::options::New(fvMesh_));

    // We explicitly do NOT want to interpolate the motion inbetween
    // different regions so bypass all the matrix manipulation.
    fvScalarMatrix TEqn
    (
        fvm::laplacian
        (
            dimensionedScalar("viscosity", dimViscosity, 1.0)
           *diffusivityPtr_->operator()(),
            cellMotionU_,
            "laplacian(diffusivity,cellMotionU)"
        )
     ==
        fvOptions(cellMotionU_)
    );

    fvOptions.constrain(TEqn);
    TEqn.solveSegregatedOrCoupled(TEqn.solverDict());
    fvOptions.correct(cellMotionU_);
}


void Foam::velocityComponentLaplacianFvMotionSolver::updateMesh
(
    const mapPolyMesh& mpm
)
{
    componentVelocityMotionSolver::updateMesh(mpm);

    // Update diffusivity. Note two stage to make sure old one is de-registered
    // before creating/registering new one.
    diffusivityPtr_.reset(nullptr);
    diffusivityPtr_ = motionDiffusivity::New
    (
        fvMesh_,
        coeffDict().lookup("diffusivity")
    );
}


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