/*---------------------------------------------------------------------------*\
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    \\  /    A nd           | Copyright (C) 2011-2026 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/>.

Class
    Foam::polyPatch

Description
    A patch is a list of labels that address the faces in the global face list.

    The patch can calculate its own edges based on the global faces.
    Patch also contains all addressing between the faces.

SourceFiles
    polyPatch.C
    polyPatchNew.C

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

#ifndef polyPatch_H
#define polyPatch_H

#include "patchIdentifier.H"
#include "primitivePatch.H"
#include "typeInfo.H"
#include "runTimeSelectionTables.H"

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

namespace Foam
{

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

// Forward declaration of friend functions and operators

class polyMesh;
class polyBoundaryMesh;
class polyPatch;
class PstreamBuffers;

Ostream& operator<<(Ostream&, const polyPatch&);


/*---------------------------------------------------------------------------*\
                          Class polyPatch Declaration
\*---------------------------------------------------------------------------*/

class polyPatch
:
    public patchIdentifier,
    public primitivePatch
{
    // Private Data

        //- Start label of this patch in the polyMesh face list
        label start_;

        //- Reference to boundary mesh
        const polyBoundaryMesh& boundaryMesh_;


        // Demand-driven private data

            //- face-cell addressing
            mutable labelList::subList* faceCellsPtr_;

            //- Global edge addressing
            mutable labelList* mePtr_;


protected:

    // Protected Member Functions

        // The polyPatch geometry initialisation is called by polyBoundaryMesh
        friend class polyBoundaryMesh;

        //- Initialise the calculation of the patch geometry
        virtual void initCalcGeometry(PstreamBuffers&)
        {}

        //- Calculate the patch geometry
        virtual void calcGeometry(PstreamBuffers&)
        {}

        //- Correct patches after moving points
        virtual void movePoints(const pointField& p);

        //- Initialise the patches for moving points
        virtual void initMovePoints(PstreamBuffers&, const pointField&)
        {}

        //- Correct patches after moving points
        virtual void movePoints(PstreamBuffers&, const pointField& p);

        //- Initialise the update of the patch topology
        virtual void initTopoChange(PstreamBuffers&)
        {}

        //- Update of the patch topology
        virtual void topoChange(PstreamBuffers&);

        //- Clear geometry
        virtual void clearGeom();

        //- Reset the patch name
        virtual void rename(const wordList& newNames);

        //- Reset the patch index
        virtual void reorder(const labelUList& newToOldIndex);


public:

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

    //- Debug switch to disallow the use of genericPolyPatch
    static int disallowGenericPolyPatch;


    // Declare run-time constructor selection tables

        declareRunTimeSelectionTable
        (
            autoPtr,
            polyPatch,
            word,
            (
                const word& name,
                const label size,
                const label start,
                const label index,
                const polyBoundaryMesh& bm
            ),
            (name, size, start, index, bm)
        );

        declareRunTimeSelectionTable
        (
            autoPtr,
            polyPatch,
            dictionary,
            (
                const word& name,
                const dictionary& dict,
                const label index,
                const polyBoundaryMesh& bm
            ),
            (name, dict, index, bm)
        );


    // Constructors

        //- Construct from components
        polyPatch
        (
            const word& name,
            const label size,
            const label start,
            const label index,
            const polyBoundaryMesh& bm
        );

        //- Construct from dictionary
        polyPatch
        (
            const word& name,
            const dictionary& dict,
            const label index,
            const polyBoundaryMesh& bm
        );

        //- Copy constructor, resetting the boundary mesh
        polyPatch(const polyPatch&, const polyBoundaryMesh&);

        //- Construct given the original patch and resetting the
        //  face list and boundary mesh information
        polyPatch
        (
            const polyPatch& pp,
            const polyBoundaryMesh& bm,
            const label index,
            const label newSize,
            const label newStart
        );

        //- Copy constructor
        polyPatch(const polyPatch&);

        //- Construct and return a clone, resetting the boundary mesh
        virtual autoPtr<polyPatch> clone(const polyBoundaryMesh& bm) const
        {
            return autoPtr<polyPatch>(new polyPatch(*this, bm));
        }

        //- Construct and return a clone, resetting the face list
        //  and boundary mesh
        virtual autoPtr<polyPatch> clone
        (
            const polyBoundaryMesh& bm,
            const label index,
            const label newSize,
            const label newStart
        ) const
        {
            return autoPtr<polyPatch>
            (
                new polyPatch(*this, bm, index, newSize, newStart)
            );
        }


    // Selectors

        //- Return a pointer to a new patch created on freestore from
        //  components
        static autoPtr<polyPatch> New
        (
            const word& patchType,
            const word& name,
            const label size,
            const label start,
            const label index,
            const polyBoundaryMesh& bm
        );

        //- Return a pointer to a new patch created on freestore from
        //  dictionary
        static autoPtr<polyPatch> New
        (
            const word& name,
            const dictionary& dict,
            const label index,
            const polyBoundaryMesh& bm
        );

        //- Return a pointer to a new patch created on freestore from
        //  dictionary
        static autoPtr<polyPatch> New
        (
            const word& patchType,
            const word& name,
            const dictionary& dict,
            const label index,
            const polyBoundaryMesh& bm
        );


    //- Destructor
    virtual ~polyPatch();


    // Member Functions

        //- Return start label of this patch in the polyMesh face list
        label start() const
        {
            return start_;
        }

        //- Return boundaryMesh reference
        const polyBoundaryMesh& boundaryMesh() const;

        //- Return mesh reference
        const polyMesh& mesh() const;

        //- Return false as this patch is not a constraint type
        virtual bool constraint() const
        {
            return false;
        }

        //- Return true if this patch is geometrically coupled (i.e. faces and
        //  points correspondence)
        virtual bool coupled() const
        {
            return false;
        }

        //- Extract face cell data
        template<class T>
        const UIndirectList<T> patchInternalList
        (
            const UList<T>& internalValues
        ) const
        {
            return UIndirectList<T>(internalValues, faceCells());
        }

        //- Slice list to patch
        template<class T>
        const typename List<T>::subList patchSlice(const UList<T>& l) const
        {
            return typename List<T>::subList(l, this->size(), start_);
        }

        //- Slice Field to patch
        template<class T>
        const typename Field<T>::subField patchSlice(const Field<T>& l) const
        {
            return typename Field<T>::subField(l, this->size(), start_);
        }


        //- Write the polyPatch data as a dictionary
        virtual void write(Ostream&) const;


        // Geometric data; point list required

            //- Return face centres
            const vectorField::subField faceCentres() const;

            //- Return face areas
            const vectorField::subField faceAreas() const;

            //- Return face area magnitudes
            const scalarField::subField magFaceAreas() const;

            //- Return face cell centres
            tmp<vectorField> faceCellCentres() const;


        // Addressing into mesh

            //- Return face-cell addressing
            const labelUList& faceCells() const;

            //- Return global edge index for local edges
            const labelList& meshEdges() const;

            //- Clear addressing
            virtual void clearAddressing();


        // Other patch operations

            //- Return label of face in patch from global face label
            inline label whichFace(const label l) const
            {
                return l - start_;
            }


        //- Initialise ordering for primitivePatch. Does not
        //  refer to *this (except for name() and type() etc.)
        virtual void initOrder(PstreamBuffers&, const primitivePatch&) const;

        //- Return new ordering for primitivePatch.
        //  Ordering is -faceMap: for every face
        //  index of the new face -rotation:for every new face the clockwise
        //  shift of the original face. Return false if nothing changes
        //  (faceMap is identity, rotation is 0), true otherwise.
        virtual bool order
        (
            PstreamBuffers&,
            const primitivePatch&,
            labelList& faceMap,
            labelList& rotation
        ) const;

        //- Reset the size and start of the patch
        void reset(const label size, const label start);


    // Member Operators

        //- Assignment
        void operator=(const polyPatch&);


    // Ostream Operator

        friend Ostream& operator<<(Ostream&, const polyPatch&);
};


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

} // End namespace Foam

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

#endif

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