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

  Program:   Visualization Toolkit
  Module:    vtkExpandSelectedGraph.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.

=========================================================================*/
/*-------------------------------------------------------------------------
  Copyright 2008 Sandia Corporation.
  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
  the U.S. Government retains certain rights in this software.
-------------------------------------------------------------------------*/

// .NAME vtkExpandSelectedGraph - expands a selection set of a vtkGraph
//
// .SECTION Description
// The first input is a vtkSelection containing the selected vertices.
// The second input is a vtkGraph.
// This filter 'grows' the selection set in one of the following ways
// 1) SetBFSDistance controls how many 'hops' the selection is grown
//    from each seed point in the selection set (defaults to 1)
// 2) IncludeShortestPaths controls whether this filter tries to 
//    'connect' the vertices in the selection set by computing the
//    shortest path between the vertices (if such a path exists)
// Note: IncludeShortestPaths is currently non-functional


#ifndef __vtkExpandSelectedGraph_h
#define __vtkExpandSelectedGraph_h

#include "vtkSelectionAlgorithm.h"

class vtkGraph;
class vtkIdTypeArray;

class VTK_INFOVIS_EXPORT vtkExpandSelectedGraph : public vtkSelectionAlgorithm
{
public:
  static vtkExpandSelectedGraph* New();
  vtkTypeRevisionMacro(vtkExpandSelectedGraph,vtkSelectionAlgorithm);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // A convenience method for setting the second input (i.e. the graph).
  void SetGraphConnection(vtkAlgorithmOutput* in);
  
  // Description:
  // Specify the first vtkSelection input and the second vtkGraph input.
  int FillInputPortInformation(int port, vtkInformation* info);
  
  // Description:
  // Set/Get BFSDistance which controls how many 'hops' the selection 
  // is grown from each seed point in the selection set (defaults to 1)
  vtkSetMacro(BFSDistance, int);
  vtkGetMacro(BFSDistance, int);
  
  // Description:
  // Set/Get IncludeShortestPaths controls whether this filter tries to 
  // 'connect' the vertices in the selection set by computing the
  // shortest path between the vertices (if such a path exists)
  // Note: IncludeShortestPaths is currently non-functional
  vtkSetMacro(IncludeShortestPaths, bool);
  vtkGetMacro(IncludeShortestPaths, bool);
  vtkBooleanMacro(IncludeShortestPaths, bool);


protected:
  vtkExpandSelectedGraph();
  ~vtkExpandSelectedGraph();

  int RequestData(
    vtkInformation*, 
    vtkInformationVector**, 
    vtkInformationVector*);

  void Expand(vtkIdTypeArray*,vtkGraph*);
    
  int BFSDistance;
  bool IncludeShortestPaths;

private:
  vtkExpandSelectedGraph(const vtkExpandSelectedGraph&); // Not implemented
  void operator=(const vtkExpandSelectedGraph&);   // Not implemented
  
  void BFSExpandSelection(vtkIdTypeArray *selection, 
                          vtkGraph *graph);
};

#endif

