/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2004-6 H. Jasak All rights reserved
     \\/     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 2 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, write to the Free Software Foundation,
    Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Application
    viscoElasticSolidFoam

Description
    visco-elastic small strain solver using finite volume method,
    using an incremental approach

Author
    Zeljko Tukovic FSB Zagreb

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

#include "fvCFD.H"
#include "constitutiveModel.H"
//#include "componentReferenceList.H"
//#include "patchToPatchInterpolation.H"

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

int main(int argc, char *argv[])
{
#   include "setRootCase.H"
#   include "createTime.H"
#   include "createMesh.H"
#   include "createFields.H"
#   include "createHistory.H"

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

    Info<< "\nStarting time loop\n" << endl;

    Info<< "Note: the results must be written for every time-step"
        << " as they are used to calculate the current stress" << endl;

    lduMatrix::debug = 0;
    scalar m = 0.5;
    surfaceVectorField n = mesh.Sf()/mesh.magSf();

    for (runTime++; !runTime.end(); runTime++)
    {
        Info<< "Time: " << runTime.timeName() << nl << endl;

#       include "readSolidMechanicsControls.H"

        volScalarField mu = rheology.mu(m*runTime.deltaT().value());
        volScalarField lambda = rheology.lambda(m*runTime.deltaT().value());
        surfaceScalarField muf = fvc::interpolate(mu);
        surfaceScalarField lambdaf = fvc::interpolate(lambda);
        Info << "average mu = " << average(muf.internalField()) << endl;
        Info << "average lambda = " << average(lambdaf.internalField()) << endl;

        int iCorr = 0;
        lduMatrix::solverPerformance solverPerf;
        scalar initialResidual = 1.0;
        scalar residual = 1.0;
        surfaceSymmTensorField DSigmaCorrf = fvc::interpolate(DSigmaCorr);
    label nCrackedFaces = 0;

    // cracking loop if you use cohesive boundaries
    //do
    //{
    do
    {
        surfaceTensorField sGradDU =
            (I - n*n)&fvc::interpolate(gradDU);

        DU.storePrevIter();

        fvVectorMatrix DUEqn
            (
                rho*fvm::d2dt2(DU)
                ==
                fvm::laplacian(2*muf+lambdaf, DU, "laplacian(DDU,DU)")
                + fvc::div
                (
                    mesh.magSf()
                    *(
                        - (muf + lambdaf)*(fvc::snGrad(DU)&(I - n*n))
                        + lambdaf*tr(sGradDU&(I - n*n))*n
                        + muf*(sGradDU&n)
                        + (n&DSigmaCorrf)
                        )
                    )
                );

//          // add an increment of gravity on the first time-step
//          if (runTime.timeIndex() == 1)
//            {
//              DUEqn -= (rho*g);
//            }

        solverPerf = DUEqn.solve();

        DU.relax();

        if (iCorr == 0)
        {
            initialResidual = solverPerf.initialResidual();
        }

        gradDU = fvc::grad(DU);

#       include "calculateDSigma.H"
#       include "calcResidual.H"

        if (iCorr % infoFrequency == 0)
        {
            Info<< "\tTime " << runTime.value()
                << ", Corrector " << iCorr
                << ", Solving for " << U.name()
                << " using " << solverPerf.solverName()
                << ", res = " << solverPerf.initialResidual()
                << ", rel res = " << residual
                << ", inner iters = " << solverPerf.nIterations() << endl;
        }
    }
    while
        (
            // solverPerf.initialResidual() > convergenceTolerance
            residual > convergenceTolerance
            && ++iCorr < nCorr
            );

    Info<< "Solving for " << DU.name() << " using "
        << solverPerf.solverName() << " solver"
        << ", Initial residula = " << initialResidual
        << ", Final residual = " << solverPerf.initialResidual()
        << ", No outer iterations " << iCorr
        << ", Relative error: " << residual << endl;

    //#           include "updateCrack.H"
    //}
    //while(nCrackedFaces > 0);

    U += DU;

#   include "calculateSigma.H"
#   include "writeFields.H"
#   include "writeHistory.H"

    Info<< "ExecutionTime = "
        << runTime.elapsedCpuTime()
        << " s\n\n" << endl;
    }

    Info<< "End\n" << endl;

    return(0);
}


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