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

  Program:   Visualization Toolkit
  Module:    vtkExtractBlock.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   vtkExtractBlock
 * @brief   extracts blocks from a multiblock dataset.
 *
 * vtkExtractBlock is a filter that extracts blocks from a multiblock dataset.
 * Each node in the multi-block tree is identified by an \c index. The index can
 * be obtained by performing a preorder traversal of the tree (including empty
 * nodes). eg. A(B (D, E), C(F, G)).
 * Inorder traversal yields: A, B, D, E, C, F, G
 * Index of A is 0, while index of C is 4.
*/

#ifndef vtkExtractBlock_h
#define vtkExtractBlock_h

#include "vtkFiltersExtractionModule.h" // For export macro
#include "vtkMultiBlockDataSetAlgorithm.h"

class vtkDataObjectTreeIterator;
class vtkMultiPieceDataSet;

class VTKFILTERSEXTRACTION_EXPORT vtkExtractBlock : public vtkMultiBlockDataSetAlgorithm
{
public:
  static vtkExtractBlock* New();
  vtkTypeMacro(vtkExtractBlock, vtkMultiBlockDataSetAlgorithm);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  //@{
  /**
   * Select the block indices to extract.
   * Each node in the multi-block tree is identified by an \c index. The index can
   * be obtained by performing a preorder traversal of the tree (including empty
   * nodes). eg. A(B (D, E), C(F, G)).
   * Inorder traversal yields: A, B, D, E, C, F, G
   * Index of A is 0, while index of C is 4.
   */
  void AddIndex(unsigned int index);
  void RemoveIndex(unsigned int index);
  void RemoveAllIndices();
  //@}

  //@{
  /**
   * When set, the output multiblock dataset will be pruned to remove empty
   * nodes. On by default.
   */
  vtkSetMacro(PruneOutput, vtkTypeBool);
  vtkGetMacro(PruneOutput, vtkTypeBool);
  vtkBooleanMacro(PruneOutput, vtkTypeBool);
  //@}

  //@{
  /**
   * This is used only when PruneOutput is ON. By default, when pruning the
   * output i.e. remove empty blocks, if node has only 1 non-null child block,
   * then that node is removed. To preserve these parent nodes, set this flag to
   * true. Off by default.
   */
  vtkSetMacro(MaintainStructure, vtkTypeBool);
  vtkGetMacro(MaintainStructure, vtkTypeBool);
  vtkBooleanMacro(MaintainStructure, vtkTypeBool);
  //@}

protected:
  vtkExtractBlock();
  ~vtkExtractBlock() override;

  /**
   * Internal key, used to avoid pruning of a branch.
   */
  static vtkInformationIntegerKey* DONT_PRUNE();

  /// Implementation of the algorithm.
  int RequestData(vtkInformation *,
                          vtkInformationVector **,
                          vtkInformationVector *) override;


  /// Extract subtree
  void CopySubTree(vtkDataObjectTreeIterator* loc,
    vtkMultiBlockDataSet* output, vtkMultiBlockDataSet* input);
  bool Prune(vtkMultiBlockDataSet* mblock);
  bool Prune(vtkMultiPieceDataSet* mblock);
  bool Prune(vtkDataObject* mblock);

  vtkTypeBool PruneOutput;
  vtkTypeBool MaintainStructure;
private:
  vtkExtractBlock(const vtkExtractBlock&) = delete;
  void operator=(const vtkExtractBlock&) = delete;

  class vtkSet;
  vtkSet *Indices;
  vtkSet *ActiveIndices;

};

#endif


