// -------------------------------------------------------------------------
// @author Leonardo Florez-Valencia (florez-l@javeriana.edu.co)
// -------------------------------------------------------------------------

#ifndef __CPEXTENSIONS__ALGORITHMS__BEZIERCURVEFUNCTION__H__
#define __CPEXTENSIONS__ALGORITHMS__BEZIERCURVEFUNCTION__H__

#include <vector>
#include <itkFunctionBase.h>
#include <itkMatrix.h>

namespace cpExtensions
{
  namespace Algorithms
  {
    /**
     * Uses the De Casteljau's algorithm.
     */
    template< class V >
    class BezierCurveFunction
      : public itk::FunctionBase< typename V::ValueType, V >
    {
    public:
      typedef BezierCurveFunction                           Self;
      typedef itk::FunctionBase< typename V::ValueType, V > Superclass;
      typedef itk::SmartPointer< Self >                     Pointer;
      typedef itk::SmartPointer< const Self >               ConstPointer;

      typedef V                     TVector;
      typedef typename V::ValueType TScalar;

      typedef
      itk::Matrix< TScalar, TVector::Dimension, TVector::Dimension >
      TFrame;
      typedef std::vector< TVector > TVectorsContainer;

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

    public:
      virtual void AddPoint( const TVector& v );
      virtual unsigned int GetNumberOfPoints( ) const;

      virtual TVector Evaluate( const TScalar& u ) const ITK_OVERRIDE;
      virtual TFrame EvaluateFrenetFrame( const TScalar& u ) const;
      virtual TScalar EvaluateLength( ) const;

    protected:
      BezierCurveFunction( );
      virtual ~BezierCurveFunction( ) { }

      void _UpdateDerivative( ) const;

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

    protected:
      TVectorsContainer m_Vectors;
      mutable Pointer   m_Derivative;
      mutable bool      m_DerivativeUpdated;
    };

  } // ecapseman

} // ecapseman

#ifndef ITK_MANUAL_INSTANTIATION
#include <cpExtensions/Algorithms/BezierCurveFunction.hxx>
#endif // ITK_MANUAL_INSTANTIATION

#endif // __CPEXTENSIONS__ALGORITHMS__BEZIERCURVEFUNCTION__H__

// eof - $RCSfile$