/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011 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/>.

Class
    Foam::nonBlockingGaussSeidelSmoother

Description
    Variant of gaussSeidelSmoother that expects processor boundary
    cells to be sorted last and so can block later. Only when the
    cells are actually visited does it need the results to be present.
    It is expected that there is little benefit to be gained from doing
    this on a patch by patch basis since the number of processor interfaces
    is quite small and the overhead of checking whether a processor interface
    is finished might be quite high (call into mpi). Also this would
    require a dynamic memory allocation to store the state of the outstanding
    requests.

SourceFiles
    nonBlockingGaussSeidelSmoother.C

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

#ifndef nonBlockingGaussSeidelSmoother_H
#define nonBlockingGaussSeidelSmoother_H

#include "lduMatrix.H"

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

namespace Foam
{

/*---------------------------------------------------------------------------*\
                           Class nonBlockingGaussSeidelSmoother Declaration
\*---------------------------------------------------------------------------*/

class nonBlockingGaussSeidelSmoother
:
    public lduMatrix::smoother
{
    // Private data

        //- Starting cell when to block
        label blockStart_;

public:

    //- Runtime type information
    TypeName("nonBlockingGaussSeidel");


    // Constructors

        //- Construct from components
        nonBlockingGaussSeidelSmoother
        (
            const word& fieldName,
            const lduMatrix& matrix,
            const FieldField<Field, scalar>& interfaceBouCoeffs,
            const FieldField<Field, scalar>& interfaceIntCoeffs,
            const lduInterfaceFieldPtrsList& interfaces
        );


    // Member Functions

        //- Smooth for the given number of sweeps
        static void smooth
        (
            const word& fieldName,
            scalarField& psi,
            const lduMatrix& matrix,
            const label blockStart,
            const scalarField& source,
            const FieldField<Field, scalar>& interfaceBouCoeffs,
            const lduInterfaceFieldPtrsList& interfaces,
            const direction cmpt,
            const label nSweeps
        );

        //- Smooth the solution for a given number of sweeps
        virtual void smooth
        (
            scalarField& psi,
            const scalarField& Source,
            const direction cmpt,
            const label nSweeps
        ) const;
};


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

} // End namespace Foam

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

#endif

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