/*=========================================================================
 *
 *  Copyright Insight Software Consortium
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#ifndef itkFastMarchingExtensionImageFilterBase_h
#define itkFastMarchingExtensionImageFilterBase_h

#include "itkFastMarchingImageFilterBase.h"
#include "itkVectorContainer.h"

namespace itk
{
/** \class FastMarchingExtensionImageFilterBase
 * \brief Extend auxiliary variables smoothly using Fast Marching.
 *
 * Fast marching can be used to extend auxiliary variables smoothly
 * from the zero level set. Starting from an initial position on the
 * front, this class simultaneously calculate the signed distance and
 * extend a set of auxiliary values.
 *
 * This class is templated over the level set image type, the auxiliary
 * variable type and the number of auxiliary variables to extended. The initial
 * front is specified by two containers: one containing the known points
 * and one containing the trial points. The auxiliary variables on the front
 * are represented by two auxiliary variable containers: one containing
 * the value of the variables at the know points and on containing the
 * value of the variables at the trail points.
 *
 * Implementation of this class is based on Chapter 11 of
 * "Level Set Methods and Fast Marching Methods", J.A. Sethian,
 * Cambridge Press, Second edition, 1999.
 *
 * For an alternative implementation, see itk::FastMarchingExtensionImageFilter.
 *
 * \sa FastMarchingExtensionImageFilter
 * \sa FastMarchingImageFilter
 * \sa LevelSetTypeDefault
 * \sa AuxVarTypeDefault
 *
 * \ingroup LevelSetSegmentation
 * \ingroup ITKFastMarching
 */
template< typename TInput, typename TOutput,
         typename TAuxValue,
         unsigned int VAuxDimension >
class ITK_TEMPLATE_EXPORT FastMarchingExtensionImageFilterBase:
  public FastMarchingImageFilterBase< TInput, TOutput >
{
public:
  ITK_DISALLOW_COPY_AND_ASSIGN(FastMarchingExtensionImageFilterBase);

  /** Standard class typdedefs. */
  using Self = FastMarchingExtensionImageFilterBase;
  using Superclass = FastMarchingImageFilterBase< TInput, TOutput >;
  using Pointer = SmartPointer< Self >;
  using ConstPointer = SmartPointer< const Self >;
  using Traits = typename Superclass::Traits;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** Run-time type information (and related methods). */
  itkTypeMacro(FastMarchingExtensionImageFilterBase,
               FastMarchingImageFilterBase);

  /** The dimension of the level set. */
  static constexpr unsigned int ImageDimension = Superclass::ImageDimension;

  /** Number of auxiliary variables to be extended. */
  static constexpr unsigned int AuxDimension = VAuxDimension;

  /** AuxVarType type alias support */
  using AuxValueType = TAuxValue;
  using AuxValueVectorType = Vector< AuxValueType, AuxDimension >;
  using AuxValueContainerType = VectorContainer< IdentifierType, AuxValueVectorType >;

  using AuxValueContainerPointer = typename AuxValueContainerType::Pointer;
  using AuxValueContainerConstIterator = typename AuxValueContainerType::ConstIterator;

  using AuxImageType = Image< AuxValueType, ImageDimension >;
  using AuxImagePointer = typename AuxImageType::Pointer;


  /** Index type alias support */
  using NodeType = typename Superclass::NodeType;
  using NodePairType = typename Superclass::NodePairType;

//  using NodeContainerType = typename Superclass::NodeContainerType;
//  using NodeContainerPointer = typename Superclass::NodeContainerPointer;
//  using NodeContainerConstIterator = typename Superclass::NodeContainerConstIterator;

  using NodePairContainerType = typename Superclass::NodePairContainerType;
  using NodePairContainerPointer = typename Superclass::NodePairContainerPointer;
  using NodePairContainerConstIterator = typename Superclass::NodePairContainerConstIterator;

  using OutputImageType = typename Superclass::OutputImageType;
  using OutputPixelType = typename Superclass::OutputPixelType;
  using InternalNodeStructure = typename Superclass::InternalNodeStructure;

  /** Get one of the extended auxiliary variable image. */
  AuxImageType * GetAuxiliaryImage( const unsigned int& idx );

  /** Set the container auxiliary values at the initial alive points. */
  itkSetObjectMacro(AuxiliaryAliveValues, AuxValueContainerType );
  itkGetModifiableObjectMacro(AuxiliaryAliveValues, AuxValueContainerType );

  /** Set the container of auxiliary values at the initial trial points. */
  itkSetObjectMacro(AuxiliaryTrialValues, AuxValueContainerType );
  itkGetModifiableObjectMacro(AuxiliaryTrialValues, AuxValueContainerType );

#ifdef ITK_USE_CONCEPT_CHECKING
  // Begin concept checking
  itkConceptMacro( AuxValueHasNumericTraitsCheck,
                   ( Concept::HasNumericTraits< TAuxValue > ) );
  // End concept checking
#endif

protected:
  FastMarchingExtensionImageFilterBase();
  ~FastMarchingExtensionImageFilterBase() override = default;
  void PrintSelf(std::ostream & os, Indent indent) const override;

  void InitializeOutput(OutputImageType *) override;

  void UpdateValue( OutputImageType* oImage, const NodeType& iValue ) override;

  /** Generate the output image meta information */
  void GenerateOutputInformation() override;

  void EnlargeOutputRequestedRegion(DataObject *output) override;

  AuxValueContainerPointer m_AuxiliaryAliveValues;
  AuxValueContainerPointer m_AuxiliaryTrialValues;

private:
  AuxImageType * m_AuxImages[VAuxDimension];
};
} // namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#include "itkFastMarchingExtensionImageFilterBase.hxx"
#endif

#endif
