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

#ifndef __fpa__Base__SingleSeedInterface__h__
#define __fpa__Base__SingleSeedInterface__h__

#include <functional>
#include <set>
#include <vector>

#include <itkConceptChecking.h>
#include <itkProcessObject.h>

namespace fpa
{
  namespace Base
  {
    /**
     */
    template< class _TVertex, class _TPoint, class _TInputValue, class _TOutputValue, class _TFrontId, class _TCompare = std::greater< _TVertex > >
    class SingleSeedInterface
    {
    public:
      itkConceptMacro(
        Check_TFrontId,
        ( itk::Concept::IsUnsignedInteger< _TFrontId > )
        );

    public:
      typedef _TVertex       TVertex;
      typedef _TPoint        TPoint;
      typedef _TInputValue   TInputValue;
      typedef _TOutputValue  TOutputValue;
      typedef _TFrontId      TFrontId;
      typedef _TCompare      TCompare;
      typedef SingleSeedInterface Self;

      struct TSeed
      {
        TVertex  Vertex;
        TPoint   Point;
        bool     IsPoint;
        bool     IsUnified;
        TFrontId FrontId;
        TSeed( )
          : IsUnified( false ),
            FrontId( TFrontId( 0 ) )
          { }
      };
      typedef std::vector< TSeed > TSeeds;

      struct TNode
      {
        TVertex  Vertex;
        TVertex  Parent;
        TFrontId FrontId;

        // Hack to hide the fact that seed values need to be initialized
        mutable TOutputValue Value;
      };
      struct TNodeCompare
      {
        bool operator()( const TNode& a, const TNode& b ) const
          {
            TCompare cmp;
            return( cmp( a.Vertex, b.Vertex ) );
          }
      };
      typedef std::set< TNode, TNodeCompare > TNodes;

    public:
      TSeeds& GetSeeds( );
      const TSeeds& GetSeeds( ) const;

      virtual void SetSeed( const TVertex& seed );
      virtual void SetSeed( const TPoint& seed );

    protected:
      SingleSeedInterface( itk::ProcessObject* filter );
      virtual ~SingleSeedInterface( );

      virtual TNodes _UnifySeeds( ) = 0;
      virtual void _PrepareSeeds( TNodes& nodes ) = 0;

    protected:
      TSeeds m_Seeds;
      itk::ProcessObject* m_Filter;
    };

  } // ecapseman

} // ecapseman

#ifndef ITK_MANUAL_INSTANTIATION
#  include <fpa/Base/SingleSeedInterface.hxx>
#endif // ITK_MANUAL_INSTANTIATION

#endif // __fpa__Base__SingleSeedInterface__h__

// eof - $RCSfile$