#ifndef __FPA__IMAGE__ALGORITHM__H__
#define __FPA__IMAGE__ALGORITHM__H__

#include <itkImage.h>
#include <itkFunctionBase.h>

namespace fpa
{
  namespace Image
  {
    namespace Functors
    {
      /**
       */
      template< class VV, class C >
      class CastVertexValueToCost
        : public itk::FunctionBase< VV, C >
      {
      public:
        // Type-related and pointers
        typedef CastVertexValueToCost           Self;
        typedef itk::FunctionBase< VV, C >      Superclass;
        typedef itk::SmartPointer< Self >       Pointer;
        typedef itk::SmartPointer< const Self > ConstPointer;

      public:
        itkNewMacro( Self );
        itkTypeMacro( CastVertexValueToCost, itkFunctionBase );

      public:
        virtual C Evaluate( const VV& v ) const
          { return( C( v ) ); }

      protected:
        CastVertexValueToCost( )
          : Superclass( )
          { }
        virtual ~CastVertexValueToCost( )
          { }

      private:
        // Purposely not implemented
        CastVertexValueToCost( const Self& );
        void operator=( const Self& );
      };

      /**
       */
      template< class VV, class C >
      class CastVertexValueToConstantCost
        : public itk::FunctionBase< VV, C >
      {
      public:
        // Type-related and pointers
        typedef CastVertexValueToConstantCost   Self;
        typedef itk::FunctionBase< VV, C >      Superclass;
        typedef itk::SmartPointer< Self >       Pointer;
        typedef itk::SmartPointer< const Self > ConstPointer;

      public:
        itkNewMacro( Self );
        itkTypeMacro( CastVertexValueToConstantCost, itkFunctionBase );

      public:
        virtual C Evaluate( const VV& v ) const
          { return( C( 1 ) ); }

      protected:
        CastVertexValueToConstantCost( )
          : Superclass( )
          { }
        virtual ~CastVertexValueToConstantCost( )
          { }

      private:
        // Purposely not implemented
        CastVertexValueToConstantCost( const Self& );
        void operator=( const Self& );
      };

    } // ecapseman

    /**
     * A generic front propagation algorithm were vertices are image pixels.
     *
     * @param I    Input image type
     * @param A    Base algorithm (RegionGrow, Dijkstra or FastMarching)
     */
    template< class I, class A, class CC >
    class Algorithm
      : public A
    {
    public:
      /// Standard class typdedefs
      typedef Algorithm                       Self;
      typedef A                               Superclass;
      typedef itk::SmartPointer< Self >       Pointer;
      typedef itk::SmartPointer< const Self > ConstPointer;

      /// Template input values
      typedef I  TInputImage;
      typedef A  TBaseAlgorithm;
      typedef CC TCostConversionFunction;

      typedef typename A::TTraits            TTraits;
      typedef typename TTraits::TCost        TCost;
      typedef typename TTraits::TResult      TResult;
      typedef typename TTraits::TVertex      TVertex;
      typedef typename TTraits::TVertexValue TVertexValue;

      typedef itk::Image< TResult, I::ImageDimension > TOutputImage;

    protected:
      typedef typename TTraits::TFrontId _TFrontId;
      typedef typename TTraits::TNode    _TNode;
      typedef typename TTraits::TNodes   _TNodes;

    private:
      typedef itk::Image< bool, I::ImageDimension >      _TMarks;
      typedef itk::Image< _TFrontId, I::ImageDimension > _TFrontsIds;
      typedef itk::Image< TVertex, I::ImageDimension >   _TParents;

    public:
      itkTypeMacro( Algorithm, TAlgorithm );

      /// Set/Get
      itkGetConstMacro( NeighborhoodOrder, unsigned int );
      itkGetConstObjectMacro( CostConversion, TCostConversionFunction );
      itkGetObjectMacro( CostConversion, TCostConversionFunction );

      itkSetMacro( NeighborhoodOrder, unsigned int );
      itkSetObjectMacro( CostConversion, TCostConversionFunction );

    protected:
      Algorithm( );
      virtual ~Algorithm( );

      /// Base interface
      virtual bool _UpdateResult( _TNode& n );

      /// Pure virtual interface: vertices
      virtual unsigned long _NumberOfVertices ( ) const;
      virtual  TVertexValue _Value            ( const TVertex& v ) const;
      virtual       TResult _Result           ( const TVertex& v ) const;

      /// Pure virtual interface: edges
      virtual double _Norm ( const TVertex& a, const TVertex& b ) const;
      virtual   bool _Edge ( const TVertex& a, const TVertex& b ) const;
      virtual  TCost _Cost ( const TVertex& a, const TVertex& b ) const;

      /// Pure virtual interface: neighborhood
      virtual void _Neighs      ( const _TNode& n, _TNodes& N ) const;
      virtual void _NeighsInDim ( const _TNode& n,
                                  const unsigned int& d,
                                  _TNodes& N );

      /// Pure virtual interface: results
      virtual void _InitializeResults ( );

    private:
      Algorithm( const Self& );      // Not impl.
      void operator=( const Self& ); // Not impl.

    protected:
      unsigned int                              m_NeighborhoodOrder;
      typename TCostConversionFunction::Pointer m_CostConversion;
    };

  } // ecapseman

} // ecapseman

#include <fpa/Image/Algorithm.hxx>

#endif // __FPA__IMAGE__ALGORITHM__H__

// eof - $RCSfile$