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

#ifndef __fpa__Base__DijkstraBase__h__
#define __fpa__Base__DijkstraBase__h__

#include <vector>

#include <itkConceptChecking.h>
#include <fpa/Base/Functors/Dijkstra/Function.h>

namespace fpa
{
  namespace Base
  {
    /**
     */
    template< class _TAlgorithm >
    class DijkstraBase
      : public _TAlgorithm
    {
    public:
      typedef DijkstraBase                    Self;
      typedef _TAlgorithm                     Superclass;
      typedef itk::SmartPointer< Self >       Pointer;
      typedef itk::SmartPointer< const Self > ConstPointer;

      typedef typename _TAlgorithm::TNode        TNode;
      typedef typename _TAlgorithm::TInputValue  TInputValue;
      typedef typename _TAlgorithm::TOutputValue TOutputValue;
      typedef typename _TAlgorithm::TVertex      TVertex;

      typedef std::vector< TNode > TQueue;
      struct TQueueOrder
      {
        bool operator()( const TNode& a, const TNode& b ) const
          {
            return( b.Value < a.Value );
          }
      };
      typedef fpa::Base::Functors::Dijkstra::Function< TVertex, TOutputValue > TWeightFunction;

    public:
      itkConceptMacro(
        Check_TOutputValue,
        ( itk::Concept::IsFloatingPoint< TOutputValue > )
        );

    public:
      itkGetObjectMacro( WeightFunction, TWeightFunction );
      itkSetObjectMacro( WeightFunction, TWeightFunction );

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

    protected:
      DijkstraBase( );
      virtual ~DijkstraBase( );

      virtual TOutputValue _ComputeOutputValue( const TNode& n ) override;
      virtual void _QueueInit( ) override;
      virtual void _QueueClear( ) override;
      virtual TNode _QueuePop( ) override;
      virtual void _QueuePush( const TNode& node ) override;
      virtual unsigned long _QueueSize( ) const override;

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

    protected:
      typename TWeightFunction::Pointer m_WeightFunction;

      TQueue      m_Queue;
      TQueueOrder m_QueueOrder;
    };

  } // ecapseman

} // ecapseman

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

#endif // __fpa__Base__DijkstraBase__h__

// eof - $RCSfile$