/*=========================================================================

 Program:   Visualization Toolkit
 Module:    vtkExtentRCBPartitioner.h

 Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
 All rights reserved.
 See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

 This software is distributed WITHOUT ANY WARRANTY; without even
 the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 PURPOSE.  See the above copyright notice for more information.

 =========================================================================*/
/**
 * @class   vtkExtentRCBPartitioner
 *
 *
 *  This method partitions a global extent to N partitions where N is a user
 *  supplied parameter.
*/

#ifndef vtkExtentRCBPartitioner_h
#define vtkExtentRCBPartitioner_h

#include "vtkCommonExecutionModelModule.h" // For export macro
#include "vtkObject.h"
#include <vector> // For STL vector
#include <cassert>  // For assert
#include <string> // For std::string

class VTKCOMMONEXECUTIONMODEL_EXPORT vtkExtentRCBPartitioner : public vtkObject
{
  public:
    static vtkExtentRCBPartitioner *New();
    vtkTypeMacro(vtkExtentRCBPartitioner,vtkObject);
    void PrintSelf(ostream &oss, vtkIndent indent ) override;

    //@{
    /**
     * Set/Get the number of requested partitions
     */
    void SetNumberOfPartitions( const int N )
    {
      assert( "pre: Number of partitions requested must be > 0" && (N >= 0) );
      this->Reset();
      this->NumberOfPartitions = N;
    }
    //@}

    //@{
    /**
     * Set/Get the global extent array to be partitioned.
     * The global extent is packed as follows:
     * [imin,imax,jmin,jmax,kmin,kmax]
     */
    void SetGlobalExtent(int imin,int imax,int jmin,int jmax,int kmin,int kmax)
    {
      this->Reset();
      this->GlobalExtent[0] = imin;
      this->GlobalExtent[1] = imax;
      this->GlobalExtent[2] = jmin;
      this->GlobalExtent[3] = jmax;
      this->GlobalExtent[4] = kmin;
      this->GlobalExtent[5] = kmax;
    }
    void SetGlobalExtent( int ext[6] )
    {
      this->SetGlobalExtent( ext[0], ext[1], ext[2], ext[3], ext[4], ext[5] );
    }
    //@}

    //@{
    /**
     * On/Off DuplicateNodes between partitions. Default is On.
     */
    vtkSetMacro(DuplicateNodes,int);
    vtkGetMacro(DuplicateNodes,int);
    vtkBooleanMacro(DuplicateNodes,int);
    //@}

    //@{
    /**
     * Set/Get macro for the number of ghost layers.
     */
    vtkSetMacro(NumberOfGhostLayers,int);
    vtkGetMacro(NumberOfGhostLayers,int);
    //@}

    //@{
    /**
     * Returns the number of extents.
     */
    vtkGetMacro(NumExtents,int);
    //@}

    /**
     * Partitions the extent
     */
    void Partition();

    /**
     * Returns the extent of the partition corresponding to the given ID.
     */
    void GetPartitionExtent( const int idx, int ext[6] );

  protected:
    vtkExtentRCBPartitioner();
   ~vtkExtentRCBPartitioner() override;

    //@{
    /**
     * Resets the partitioner to the initial state, all previous partition
     * extents are cleared.
     */
    void Reset()
    {
     this->PartitionExtents.clear();
     this->NumExtents          = 0;
     this->ExtentIsPartitioned = false;
    }
    //@}

    /**
     * Given an extent, this method will create ghost layers on each side of
     * the boundary in each dimension. The ghost layers however will be
     * restricted to the given global extent.
     */
    void ExtendGhostLayers( int ext[6] );

    //@{
    /**
     * Givent an extent and the min/max of the dimension we are looking at, this
     * method will produce a ghosted extent which is clamped within the given
     * global extent
     */
    void GetGhostedExtent(
        int ext[6], const int minIdx, const int maxIdx )
    {
      ext[minIdx]-=this->NumberOfGhostLayers;
      ext[maxIdx]+=this->NumberOfGhostLayers;
      ext[minIdx] = (ext[minIdx] < this->GlobalExtent[minIdx])?
          this->GlobalExtent[minIdx] : ext[minIdx];
      ext[maxIdx] = (ext[maxIdx] > this->GlobalExtent[maxIdx])?
          this->GlobalExtent[maxIdx] : ext[maxIdx];
    }
    //@}

    /**
     * Gets the structured data-description based on the givenn global extent
     */
    void AcquireDataDescription();

     /**
      * Returns the extent at the position corresponding to idx.
      */
     void GetExtent( const int idx, int ext[6] );

     /**
      * Adds the extent to the end of the list of partitioned extents
      */
     void AddExtent(int ext[6]);

     /**
      * Replaces the extent at the position indicated by idx with the provided
      * extent.
      */
     void ReplaceExtent(const int idx, int ext[6]);

     /**
      * Splits the extent along the given dimension.
      */
     void SplitExtent(int parent[6],int s1[6],int s2[6],int splitDimension);

     /**
      * Returns the total number of extents. It's always the 2^N where
      * N is the number of subdivisions.
      */
     int GetNumberOfTotalExtents();

     /**
      * Computes the total number of nodes for the given structured grid extent
      */
     int GetNumberOfNodes( int ext[6] );

     /**
      * Computes the total number of cells for the given structured grid extent
      */
     int GetNumberOfCells( int ext[6] );

     /**
      * Returns the length of the longest dimension
      */
     int GetLongestDimensionLength( int ext[6] );

     /**
      * Returns the longest edge
      */
     int GetLongestDimension( int ext[6] );

     /**
      * A convenience method for debugging purposes.
      */
     void PrintExtent( const std::string& name, int ext[6] );

     int NumberOfGhostLayers;
     int DataDescription;
     int GlobalExtent[6];
     int NumberOfPartitions;
     int NumExtents;

     int DuplicateNodes; // indicates whether nodes are duplicated between
                         // partitions, so that they are abutting. This is
                         // set to true by default. If disabled, the resulting
                         // partitions will have gaps.

     bool ExtentIsPartitioned;

     std::vector<int> PartitionExtents;

  private:
    vtkExtentRCBPartitioner( const vtkExtentRCBPartitioner& ) = delete;
    void operator=( const vtkExtentRCBPartitioner& ) = delete;
};

#endif /* VTKEXTENTRCBPARTITIONER_H_ */