// =========================================================================
// @author Leonardo Florez Valencia
// @email florez-l@javeriana.edu.co
// =========================================================================

#ifndef __fpa__Image__SkeletonFilter__h__
#define __fpa__Image__SkeletonFilter__h__

#include <map>

#include <itkProcessObject.h>
#include <itkSignedMaurerDistanceMapImageFilter.h>

#include <fpa/Image/Dijkstra.h>
#include <fpa/Image/Skeleton.h>

namespace fpa
{
  namespace Image
  {
    /**
     */
    template< class _TInputImage, class _TDistanceMap = itk::SignedMaurerDistanceMapImageFilter< _TInputImage, itk::Image< double, _TInputImage::ImageDimension > > >
    class SkeletonFilter
      : public itk::ProcessObject
    {
    public:
      typedef SkeletonFilter                  Self;
      typedef itk::ProcessObject              Superclass;
      typedef itk::SmartPointer< Self >       Pointer;
      typedef itk::SmartPointer< const Self > ConstPointer;

      typedef _TInputImage  TInputImage;
      typedef _TDistanceMap TDistanceMap;
      itkStaticConstMacro(
        Dimension,
        unsigned int,
        TInputImage::ImageDimension
        );

      typedef typename TDistanceMap::OutputImageType TOutputImage;
      typedef typename TInputImage::IndexType        TIndex;
      typedef typename TOutputImage::PixelType       TScalar;

      typedef fpa::Image::Skeleton< Self::Dimension > TSkeleton;

    protected:
      typedef std::multimap< TScalar, TIndex > _TSkeletonQueue;

      /**
       */
      class _TDijkstra
        : public fpa::Image::Dijkstra< TOutputImage, TOutputImage >
      {
      public:
        typedef _TDijkstra                                         Self;
        typedef fpa::Image::Dijkstra< TOutputImage, TOutputImage > Superclass;
        typedef itk::SmartPointer< Self >                          Pointer;
        typedef itk::SmartPointer< const Self >                    ConstPointer;

        typedef typename Superclass::TNode TNode;
        typedef typename Superclass::TMST  TMST;

      public:
        itkNewMacro( Self );
        itkTypeMacro( _TDijkstra, fpa::Image::Dijkstra );

        itkGetConstReferenceMacro( SkeletonQueue, _TSkeletonQueue );

      protected:
        _TDijkstra( );
        virtual ~_TDijkstra( );

        virtual void _BeforeGenerateData( ) override;
        virtual void _UpdateOutputValue( TNode& n ) override;

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

      protected:
        _TSkeletonQueue m_SkeletonQueue;
      };
      typedef typename _TDijkstra::TMST _TMST;

    public:
      itkNewMacro( Self );
      itkTypeMacro( fpa::Image::SkeletonFilter, fpa::Image::Dijkstra );

      itkBooleanMacro( SeedFromMaximumDistance );
      itkGetConstMacro( SeedFromMaximumDistance, bool );
      itkSetMacro( SeedFromMaximumDistance, bool );

      itkGetConstObjectMacro( DistanceMap, TDistanceMap );
      itkGetObjectMacro( DistanceMap, TDistanceMap );

      itkGetConstMacro( Seed, TIndex );
      itkSetMacro( Seed, TIndex );

    public:
      virtual itk::ModifiedTimeType GetMTime( ) const override;

      void SetInput( TInputImage* input );
      TInputImage* GetInput( );
      const TInputImage* GetInput( ) const;

      TSkeleton* GetOutput( );
      const TSkeleton* GetOutput( ) const;

    protected:
      SkeletonFilter( );
      virtual ~SkeletonFilter( );

      virtual void GenerateData( ) override;

      template< class _TMarksPointer >
      void _MarkSphere(
        _TMarksPointer& marks,
        const TOutputImage* dmap,
        const TIndex& center
        );

      void _EndPoints(
        std::vector< TIndex >& end_points,
        const TOutputImage* dmap,
        const _TMST* mst,
        const _TSkeletonQueue& queue
        );

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

    protected:
      typename TDistanceMap::Pointer m_DistanceMap;
      bool   m_SeedFromMaximumDistance;
      TIndex m_Seed;
    };

  } // ecapseman

} // ecapseman

#ifndef ITK_MANUAL_INSTANTIATION
#  include <fpa/Image/SkeletonFilter.hxx>
#endif // ITK_MANUAL_INSTANTIATION

#endif // __fpa__Image__SkeletonFilter__h__

// eof - $RCSfile$