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

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    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::localPointRegion

Description
    Takes mesh with 'baffles' (= boundary faces sharing points).
    Determines for selected points on boundary faces the 'point region' it is
    connected to. Each region can be visited by a cell-face-cell walk.
    Used in duplicating points after splitting baffles.

    Regions are not consecutive per processor. They will be -1..nRegions_.

    Note: coupled boundaries (cyclics, parallel) not fully tested.

SourceFiles
    localPointRegion.C

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

#ifndef localPointRegion_H
#define localPointRegion_H

#include "typeInfo.H"
#include "Map.H"
#include "labelList.H"
#include "HashSet.H"
#include "faceList.H"
#include "boolList.H"
#include "labelPair.H"

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

namespace Foam
{

// Forward declaration of classes
class primitiveMesh;
class polyMesh;
class face;
class polyTopoChangeMap;

/*---------------------------------------------------------------------------*\
                      Class localPointRegion Declaration
\*---------------------------------------------------------------------------*/

class localPointRegion
{
    // Private Data

        ////- (global) number of regions
        // label nRegions_;

        //- Per point that is to duplicated to the local index
        Map<label> meshPointMap_;

        //- Per local point the regions it is in
        labelListList pointRegions_;

        //- Per face that uses a duplicated point the local index
        Map<label> meshFaceMap_;

        //- Per face the region of its points
        faceList faceRegions_;


    // Private Member Functions

        //- Given minimum cell the points on a face are connected to
        //  determine the points to be duplicated.
        void countPointRegions
        (
            const polyMesh& mesh,
            const boolList& candidatePoint,
            const Map<label>& candidateFace,
            faceList& minRegion
        );

        //- Do all: calculate points that need to be duplicated.
        void calcPointRegions
        (
            const polyMesh& mesh,
            boolList& candidatePoint
        );


        //- Check if two faces are equal. If forward = false checks f1 in
        //  reverse order.
        static bool isDuplicate
        (
            const face& f0,
            const face& f1,
            const bool forward
        );

public:

    //- Runtime type information
    ClassName("localPointRegion");


    // Constructors

        //- Construct from mesh. Assumes all non-coupled boundary points
        //  are candidates for duplication
        localPointRegion(const polyMesh& mesh);

        //- Construct from mesh and candidate points for duplication
        localPointRegion
        (
            const polyMesh& mesh,
            const labelList& candidatePoints
        );


    // Member Functions

        // Static Member Functions

            //- Helper routine to find baffles (two boundary faces using the
            //  same points but in reverse order)
            //  Gets list of (boundary!) faces to check. Returns labelList
            //  of same size as the input list
            //  with -1 or index of other face in the input list.
            //  Does not handle duplicate faces on both sides of processor patch
            static labelList findDuplicateFaces
            (
                const primitiveMesh&,
                const labelList&
            );

            //- Helper routine to find all baffles (two boundary faces
            //  using the same points but in reverse order)
            static labelPairList findDuplicateFacePairs(const polyMesh&);

        // Access

            ////- Global number of regions. TBD. regions not compacted yet.
            // label nRegions() const
            //{
            //    return nRegions_;
            //}

            //- Per point that is to be duplicated the local index
            const Map<label>& meshPointMap() const
            {
                return meshPointMap_;
            }

            //- Per local point the regions it is in
            const labelListList& pointRegions() const
            {
                return pointRegions_;
            }

            //- Per face that uses a duplicated point the local index
            const Map<label>& meshFaceMap() const
            {
                return meshFaceMap_;
            }

            //- Per face the region of its points
            const faceList& faceRegions() const
            {
                return faceRegions_;
            }


        // Edit

            //- Force recalculation of locally stored data on topological change
            void topoChange(const polyTopoChangeMap&);
};


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

} // End namespace Foam

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

#endif

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