// =========================================================================
// @author Leonardo Florez-Valencia (florez-l@javeriana.edu.co)
// =========================================================================
#ifndef __RandomWalkSegmentation__h__
#define __RandomWalkSegmentation__h__

#include <itkImageToImageFilter.h>
#include <fpa/Config.h>
#include <fpa/DataStructures/Image/Path.h>

/**
 */
template< class _TInputImage, class _TOutputImage >
class RandomWalkSegmentation
  : public itk::ImageToImageFilter< _TInputImage, _TOutputImage >
{
public:
  typedef _TInputImage  TInputImage;
  typedef _TOutputImage TOutputImage;

  typedef itk::ImageToImageFilter< TInputImage, TOutputImage > Superclass;
  typedef RandomWalkSegmentation        Self;
  typedef itk::SmartPointer< Self >       Pointer;
  typedef itk::SmartPointer< const Self > ConstPointer;

  typedef typename TInputImage::IndexType TIndex;
  typedef typename TInputImage::PointType TPoint;

  struct TSeed
  {
    TIndex Index;
    TPoint Point;
    bool IsPoint;
  };
  typedef fpa::DataStructures::Image::Path< TInputImage::ImageDimension > TPath;

public:
  itkNewMacro( Self );
  itkTypeMacro( RandomWalkSegmentation, itk::ImageToImageFilter );

  itkGetConstMacro( StartSeed, TSeed );
  itkGetConstMacro( EndSeed, TSeed );

  itkGetConstMacro( Beta, double );
  itkSetMacro( Beta, double );

  itkGetConstMacro( Sigma, double );
  itkSetMacro( Sigma, double );

  itkGetConstMacro( Radius, double );
  itkSetMacro( Radius, double );

  fpaFilterOutputMacro( OutputAxis, TPath );

public:
  void AddSeed( const TIndex& s );
  void AddSeed( const TPoint& s );
  void ClearSeeds( );
  unsigned long GetNumberOfSeeds( ) const;

  void SetStartSeed( const TIndex& s );
  void SetStartSeed( const TPoint& s );

  void SetEndSeed( const TIndex& s );
  void SetEndSeed( const TPoint& s );

protected:
  RandomWalkSegmentation( );
  virtual ~RandomWalkSegmentation( );

  virtual void GenerateData( ) override;

private:
  template< class _TImage >
  void _save( _TImage* image, const std::string& fname );

private:
  // Purposely not implemented
  RandomWalkSegmentation( const Self& other );
  Self& operator=( const Self& other );

protected:
  TSeed m_StartSeed;
  TSeed m_EndSeed;
  std::vector< TSeed > m_Seeds;

  double m_Beta;
  double m_Sigma;
  double m_Radius;
};

#ifndef ITK_MANUAL_INSTANTIATION
#  include "RandomWalkSegmentation.hxx"
#endif // ITK_MANUAL_INSTANTIATION

#endif // __RandomWalkSegmentation__h__

// eof - $RCSfile$