/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2014 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 "LduMatrix.H"
#include "diagTensorField.H"

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

template<class Type>
void Foam::fvMatrix<Type>::setComponentReference
(
    const label patchi,
    const label facei,
    const direction cmpt,
    const scalar value
)
{
    if (psi_.needReference())
    {
        if (Pstream::master())
        {
            internalCoeffs_[patchi][facei].component(cmpt) +=
                diag()[psi_.mesh().boundary()[patchi].faceCells()[facei]];

            boundaryCoeffs_[patchi][facei].component(cmpt) +=
                diag()[psi_.mesh().boundary()[patchi].faceCells()[facei]]
               *value;
        }
    }
}


template<class Type>
Foam::solverPerformance Foam::fvMatrix<Type>::solve
(
    const dictionary& solverControls
)
{
    if (debug)
    {
        Info.masterStream(this->mesh().comm())
            << "fvMatrix<Type>::solve(const dictionary& solverControls) : "
               "solving fvMatrix<Type>"
            << endl;
    }

    label maxIter = -1;
    if (solverControls.readIfPresent("maxIter", maxIter))
    {
        if (maxIter == 0)
        {
            return solverPerformance();
        }
    }

    word type(solverControls.lookupOrDefault<word>("type", "segregated"));

    if (type == "segregated")
    {
        return solveSegregated(solverControls);
    }
    else if (type == "coupled")
    {
        return solveCoupled(solverControls);
    }
    else
    {
        FatalIOErrorIn
        (
            "fvMatrix<Type>::solve(const dictionary& solverControls)",
            solverControls
        )   << "Unknown type " << type
            << "; currently supported solver types are segregated and coupled"
            << exit(FatalIOError);

        return solverPerformance();
    }
}


template<class Type>
Foam::solverPerformance Foam::fvMatrix<Type>::solveSegregated
(
    const dictionary& solverControls
)
{
    if (debug)
    {
        Info.masterStream(this->mesh().comm())
            << "fvMatrix<Type>::solveSegregated"
               "(const dictionary& solverControls) : "
               "solving fvMatrix<Type>"
            << endl;
    }

    GeometricField<Type, fvPatchField, volMesh>& psi =
       const_cast<GeometricField<Type, fvPatchField, volMesh>&>(psi_);

    solverPerformance solverPerfVec
    (
        "fvMatrix<Type>::solveSegregated",
        psi.name()
    );

    scalarField saveDiag(diag());

    Field<Type> source(source_);

    // At this point include the boundary source from the coupled boundaries.
    // This is corrected for the implict part by updateMatrixInterfaces within
    // the component loop.
    addBoundarySource(source);

    typename Type::labelType validComponents
    (
        pow
        (
            psi.mesh().solutionD(),
            pTraits<typename powProduct<Vector<label>, Type::rank>::type>::zero
        )
    );

    for (direction cmpt=0; cmpt<Type::nComponents; cmpt++)
    {
        if (validComponents[cmpt] == -1) continue;

        // copy field and source

        scalarField psiCmpt(psi.internalField().component(cmpt));
        addBoundaryDiag(diag(), cmpt);

        scalarField sourceCmpt(source.component(cmpt));

        FieldField<Field, scalar> bouCoeffsCmpt
        (
            boundaryCoeffs_.component(cmpt)
        );

        FieldField<Field, scalar> intCoeffsCmpt
        (
            internalCoeffs_.component(cmpt)
        );

        lduInterfaceFieldPtrsList interfaces =
            psi.boundaryField().scalarInterfaces();

        // Use the initMatrixInterfaces and updateMatrixInterfaces to correct
        // bouCoeffsCmpt for the explicit part of the coupled boundary
        // conditions
        initMatrixInterfaces
        (
            bouCoeffsCmpt,
            interfaces,
            psiCmpt,
            sourceCmpt,
            cmpt
        );

        updateMatrixInterfaces
        (
            bouCoeffsCmpt,
            interfaces,
            psiCmpt,
            sourceCmpt,
            cmpt
        );

        solverPerformance solverPerf;

        // Solver call
        solverPerf = lduMatrix::solver::New
        (
            psi.name() + pTraits<Type>::componentNames[cmpt],
            *this,
            bouCoeffsCmpt,
            intCoeffsCmpt,
            interfaces,
            solverControls
        )->solve(psiCmpt, sourceCmpt, cmpt);

        if (solverPerformance::debug)
        {
            solverPerf.print(Info.masterStream(this->mesh().comm()));
        }

        solverPerfVec = max(solverPerfVec, solverPerf);
        solverPerfVec.solverName() = solverPerf.solverName();

        psi.internalField().replace(cmpt, psiCmpt);
        diag() = saveDiag;
    }

    psi.correctBoundaryConditions();

    psi.mesh().setSolverPerformance(psi.name(), solverPerfVec);

    return solverPerfVec;
}


template<class Type>
Foam::solverPerformance Foam::fvMatrix<Type>::solveCoupled
(
    const dictionary& solverControls
)
{
    if (debug)
    {
        Info.masterStream(this->mesh().comm())
            << "fvMatrix<Type>::solveCoupled"
               "(const dictionary& solverControls) : "
               "solving fvMatrix<Type>"
            << endl;
    }

    GeometricField<Type, fvPatchField, volMesh>& psi =
       const_cast<GeometricField<Type, fvPatchField, volMesh>&>(psi_);

    LduMatrix<Type, scalar, scalar> coupledMatrix(psi.mesh());
    coupledMatrix.diag() = diag();
    coupledMatrix.upper() = upper();
    coupledMatrix.lower() = lower();
    coupledMatrix.source() = source();

    addBoundaryDiag(coupledMatrix.diag(), 0);
    addBoundarySource(coupledMatrix.source(), false);

    coupledMatrix.interfaces() = psi.boundaryField().interfaces();
    coupledMatrix.interfacesUpper() = boundaryCoeffs().component(0);
    coupledMatrix.interfacesLower() = internalCoeffs().component(0);

    autoPtr<typename LduMatrix<Type, scalar, scalar>::solver>
    coupledMatrixSolver
    (
        LduMatrix<Type, scalar, scalar>::solver::New
        (
            psi.name(),
            coupledMatrix,
            solverControls
        )
    );

    SolverPerformance<Type> solverPerf
    (
        coupledMatrixSolver->solve(psi)
    );

    if (SolverPerformance<Type>::debug)
    {
        solverPerf.print(Info.masterStream(this->mesh().comm()));
    }

    psi.correctBoundaryConditions();

    //create a summary of the maximum residuals and iterations
    solverPerformance solverPerfSummary = summary(solverPerf);

    psi.mesh().setSolverPerformance(psi.name(), solverPerfSummary);

    return solverPerfSummary;
}


template<class Type>
Foam::autoPtr<typename Foam::fvMatrix<Type>::fvSolver>
Foam::fvMatrix<Type>::solver()
{
    return solver
    (
        psi_.mesh().solverDict
        (
            psi_.select
            (
                psi_.mesh().data::template lookupOrDefault<bool>
                ("finalIteration", false)
            )
        )
    );
}


template<class Type>
Foam::solverPerformance Foam::fvMatrix<Type>::fvSolver::solve()
{
    return solve
    (
        fvMat_.psi_.mesh().solverDict
        (
            fvMat_.psi_.select
            (
                fvMat_.psi_.mesh().data::template lookupOrDefault<bool>
                ("finalIteration", false)
            )
        )
    );
}


template<class Type>
Foam::solverPerformance Foam::fvMatrix<Type>::solve()
{
    return solve
    (
        psi_.mesh().solverDict
        (
            psi_.select
            (
                psi_.mesh().data::template lookupOrDefault<bool>
                ("finalIteration", false)
            )
        )
    );
}


template<class Type>
Foam::tmp<Foam::Field<Type> > Foam::fvMatrix<Type>::residual() const
{
    tmp<Field<Type> > tres(new Field<Type>(source_));
    Field<Type>& res = tres();

    addBoundarySource(res);

    // Loop over field components
    for (direction cmpt=0; cmpt<Type::nComponents; cmpt++)
    {
        scalarField psiCmpt(psi_.internalField().component(cmpt));

        scalarField boundaryDiagCmpt(psi_.size(), 0.0);
        addBoundaryDiag(boundaryDiagCmpt, cmpt);

        FieldField<Field, scalar> bouCoeffsCmpt
        (
            boundaryCoeffs_.component(cmpt)
        );

        res.replace
        (
            cmpt,
            lduMatrix::residual
            (
                psiCmpt,
                res.component(cmpt) - boundaryDiagCmpt*psiCmpt,
                bouCoeffsCmpt,
                psi_.boundaryField().scalarInterfaces(),
                cmpt
            )
        );
    }

    return tres;
}


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

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2013 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 "SolverPerformance.H"
#include "IOstreams.H"

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

template<class Type>
typename Foam::SolverPerformance<Type>::componentType
Foam::SolverPerformance<Type>::maxInitialResidual() const
{
    componentType maxValue = pTraits<componentType>::min;

    for(direction cmpt=0; cmpt<pTraits<Type>::nComponents; cmpt++)
    {
        if(maxValue < component(initialResidual_, cmpt))
        {
            maxValue = component(initialResidual_, cmpt);
        }
    }

    return maxValue;
}


template<class Type>
typename Foam::SolverPerformance<Type>::componentType
Foam::SolverPerformance<Type>::maxFinalResidual() const
{
    componentType maxValue = pTraits<componentType>::min;

    for(direction cmpt=0; cmpt<pTraits<Type>::nComponents; cmpt++)
    {
        if(maxValue < component(finalResidual_, cmpt))
        {
            maxValue = component(finalResidual_, cmpt);
        }
    }

    return maxValue;
}


template<class Type>
bool Foam::SolverPerformance<Type>::checkSingularity
(
    const Type& wApA
)
{
    for(direction cmpt=0; cmpt<pTraits<Type>::nComponents; cmpt++)
    {
        singular_[cmpt] =
            component(wApA, cmpt) < vsmall_;
    }

    return singular();
}


template<class Type>
bool Foam::SolverPerformance<Type>::singular() const
{
    for(direction cmpt=0; cmpt<pTraits<Type>::nComponents; cmpt++)
    {
        if (!singular_[cmpt]) return false;
    }

    return true;
}


template<class Type>
bool Foam::SolverPerformance<Type>::checkConvergence
(
    const Type& Tolerance,
    const Type& RelTolerance
)
{
    if (debug >= 2)
    {
        Info<< solverName_
            << ":  Iteration " << noIterations_
            << " residual = " << finalResidual_
            << endl;
    }

    if
    (
        finalResidual_ < Tolerance
     || (
            RelTolerance
          > small_*pTraits<Type>::one
         && finalResidual_ < cmptMultiply(RelTolerance, initialResidual_)
        )
    )
    {
        converged_ = true;
    }
    else
    {
        converged_ = false;
    }

    return converged_;
}


template<class Type>
void Foam::SolverPerformance<Type>::print
(
    Ostream& os
) const
{
    for(direction cmpt=0; cmpt<pTraits<Type>::nComponents; cmpt++)
    {
        if (pTraits<Type>::nComponents == 1)
        {
            os  << solverName_ << ":  Solving for " << fieldName_;

        }
        else
        {
            os  << solverName_ << ":  Solving for "
                << word(fieldName_ + pTraits<Type>::componentNames[cmpt]);
        }

        if (singular_[cmpt])
        {
            os  << ":  solution singularity" << endl;
        }
        else
        {
            os  << ", Initial residual = " << component(initialResidual_, cmpt)
                << ", Final residual = " << component(finalResidual_, cmpt)
                << ", No Iterations " << noIterations_
                << endl;
        }
    }
}


template<class Type>
bool Foam::SolverPerformance<Type>::operator!=
(
    const SolverPerformance<Type>& sp
) const
{
    return
    (
        solverName()      != sp.solverName()
     || fieldName()       != sp.fieldName()
     || initialResidual() != sp.initialResidual()
     || finalResidual()   != sp.finalResidual()
     || nIterations()     != sp.nIterations()
     || converged()       != sp.converged()
     || singular()        != sp.singular()
    );
}


template<class Type>
Foam::SolverPerformance<typename Foam::pTraits<Type>::cmptType>
Foam::summary(const SolverPerformance<Type>& sp)
{
  return 
      SolverPerformance<typename pTraits<Type>::cmptType>
      (
          sp.solverName(),
          sp.fieldName(),
          sp.maxInitialResidual(),
          sp.maxFinalResidual(),
          sp.nIterations(),
          sp.converged(),
          sp.singular()
      );
}


template<class Type>
typename Foam::SolverPerformance<Type> Foam::max
(
    const typename Foam::SolverPerformance<Type>& sp1,
    const typename Foam::SolverPerformance<Type>& sp2
)
{
    return SolverPerformance<Type>
    (
        sp1.solverName(),
        sp1.fieldName_,
        max(sp1.initialResidual(), sp2.initialResidual()),
        max(sp1.finalResidual(), sp2.finalResidual()),
        max(sp1.nIterations(), sp2.nIterations()),
        sp1.converged() && sp2.converged(),
        sp1.singular() || sp2.singular()
    );
}


template<class Type>
Foam::Istream& Foam::operator>>
(
    Istream& is,
    typename Foam::SolverPerformance<Type>& sp
)
{
    is.readBeginList("SolverPerformance<Type>");
    is  >> sp.solverName_
        >> sp.fieldName_
        >> sp.initialResidual_
        >> sp.finalResidual_
        >> sp.noIterations_
        >> sp.converged_
        >> sp.singular_;
    is.readEndList("SolverPerformance<Type>");

    return is;
}


template<class Type>
Foam::Ostream& Foam::operator<<
(
    Ostream& os,
    const typename Foam::SolverPerformance<Type>& sp
)
{
    os  << token::BEGIN_LIST
        << sp.solverName_ << token::SPACE
        << sp.fieldName_ << token::SPACE
        << sp.initialResidual_ << token::SPACE
        << sp.finalResidual_ << token::SPACE
        << sp.noIterations_ << token::SPACE
        << sp.converged_ << token::SPACE
        << sp.singular_ << token::SPACE
        << token::END_LIST;

    return os;
}


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

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2012-2013 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::SolverPerformance

Description
    SolverPerformance is the class returned by the LduMatrix solver
    containing performance statistics.

SourceFiles
    SolverPerformance.C

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

#ifndef SolverPerformance_H
#define SolverPerformance_H

#include "word.H"
#include "FixedList.H"

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

namespace Foam
{

// Forward declaration of friend functions and operators

template<class Type>
class SolverPerformance;

//- Return a summary version of the solver performance with the
//  maximum values
template<class Type>
SolverPerformance<typename Foam::pTraits<Type>::cmptType>
summary(const SolverPerformance<Type>& sp);

template<class Type>
SolverPerformance<Type> max
(
    const SolverPerformance<Type>&,
    const SolverPerformance<Type>&
);

template<class Type>
Istream& operator>>
(
    Istream&,
    SolverPerformance<Type>&
);

template<class Type>
Ostream& operator<<
(
    Ostream&,
    const SolverPerformance<Type>&
);


/*---------------------------------------------------------------------------*\
                       Class SolverPerformance Declaration
\*---------------------------------------------------------------------------*/

template<class Type>
class SolverPerformance
{
    word   solverName_;
    word   fieldName_;
    Type   initialResidual_;
    Type   finalResidual_;
    label  noIterations_;
    bool   converged_;
    FixedList<bool, pTraits<Type>::nComponents> singular_;

public:

    //Typedefs

        typedef typename pTraits<Type>::cmptType componentType;

    // Static data

        // Declare name of the class and its debug switch
        ClassName("SolverPerformance");

        //- Large Type for the use in solvers
        static const scalar great_;

        //- Small Type for the use in solvers
        static const scalar small_;

        //- Very small Type for the use in solvers
        static const scalar vsmall_;


    // Constructors

        SolverPerformance()
        :
            initialResidual_(pTraits<Type>::zero),
            finalResidual_(pTraits<Type>::zero),
            noIterations_(0),
            converged_(false),
            singular_(false)
        {}


        SolverPerformance
        (
            const word&  solverName,
            const word&  fieldName,
            const Type&  iRes = pTraits<Type>::zero,
            const Type&  fRes = pTraits<Type>::zero,
            const label  nIter = 0,
            const bool   converged = false,
            const bool   singular = false
        )
        :
            solverName_(solverName),
            fieldName_(fieldName),
            initialResidual_(iRes),
            finalResidual_(fRes),
            noIterations_(nIter),
            converged_(converged),
            singular_(singular)
        {}


    // Member functions

        //- Return solver name
        const word& solverName() const
        {
            return solverName_;
        }

        //- Return solver name
        word& solverName()
        {
            return solverName_;
        }


        //- Return field name
        const word& fieldName() const
        {
            return fieldName_;
        }


        //- Return initial residual
        const Type& initialResidual() const
        {
            return initialResidual_;
        }

        //- Return initial residual
        Type& initialResidual()
        {
            return initialResidual_;
        }

        //- Return the maximum initial residual from the list
        componentType maxInitialResidual() const;


        //- Return final residual
        const Type& finalResidual() const
        {
            return finalResidual_;
        }

        //- Return final residual
        Type& finalResidual()
        {
            return finalResidual_;
        }

        //- Return the maximum final residual from the list
        componentType maxFinalResidual() const;


        //- Return number of iterations
        label nIterations() const
        {
            return noIterations_;
        }

        //- Return number of iterations
        label& nIterations()
        {
            return noIterations_;
        }


        //- Has the solver converged?
        bool converged() const
        {
            return converged_;
        }

        //- Is the matrix singular?
        bool singular() const;

        //- Check, store and return convergence
        bool checkConvergence
        (
            const Type& tolerance,
            const Type& relTolerance
        );

        //- Singularity test
        bool checkSingularity(const Type& residual);

        //- Print summary of solver performance to the given stream
        void print(Ostream& os) const;

    // Member Operators

        bool operator!=(const SolverPerformance<Type>&) const;


    // Friend functions

        //- Return the element-wise maximum of two SolverPerformance<Type>s
        friend SolverPerformance<Type> max <Type>
        (
            const SolverPerformance<Type>&,
            const SolverPerformance<Type>&
        );


    // Ostream Operator

        friend Istream& operator>> <Type>
        (
            Istream&,
            SolverPerformance<Type>&
        );

        friend Ostream& operator<< <Type>
        (
            Ostream&,
            const SolverPerformance<Type>&
        );
};


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

} // End namespace Foam

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

#define makeSolverPerformance(Type)                                           \
                                                                              \
typedef Foam::SolverPerformance<Type>                                         \
    solverPerformance##Type;                                                  \
                                                                              \
defineNamedTemplateTypeNameAndDebug(solverPerformance##Type, 0);              \
                                                                              \
template<>                                                                    \
const scalar solverPerformance##Type::great_(1e20);                           \
                                                                              \
template<>                                                                    \
const scalar solverPerformance##Type::small_(1e-20);                          \
                                                                              \
template<>                                                                    \
const scalar solverPerformance##Type::vsmall_(VSMALL);                        \


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

#ifdef NoRepository
#   include "SolverPerformance.C"
#endif

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

#endif

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