/*=========================================================================
 *
 *  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 itkReinitializeLevelSetImageFilter_h
#define itkReinitializeLevelSetImageFilter_h

#include "itkLevelSetNeighborhoodExtractor.h"
#include "itkFastMarchingImageFilter.h"

namespace itk
{
/** \class ReinitializeLevelSetImageFilter
 *  \brief Reinitialize the level set to the signed distance function.
 *
 * ReinitializeLevelSetImageFilter reinitializes the input level set to
 * the approximated signed distance function from a particular
 * level set. The output is a level set of the same type as the input.
 *
 * For some level set algorithms, it is useful to periodically
 * reinitialize the level set function to prevent numerical accuracy
 * problems in computing derivatives and curvature values where level
 * sets are densely bunched together.
 *
 * This class is templated over the image type which represents
 * the level set.
 *
 * This class supports narrowbanding. If the input narrowband is provided,
 * the algorithm will only locate the level set within the input narrowband.
 * For the output, the reinitialize level set is only valid for a distance
 * of OutputNarrowBandwidth / 2 of either side of the level set of interest.
 *
 * 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.
 *
 * \ingroup LevelSetSegmentation
 *
 * \ingroup ITKLevelSets
 */
template< typename TLevelSet >
class ITK_TEMPLATE_EXPORT ReinitializeLevelSetImageFilter:
  public ImageToImageFilter< TLevelSet, TLevelSet >
{
public:
  ITK_DISALLOW_COPY_AND_ASSIGN(ReinitializeLevelSetImageFilter);

  /** Standard class type aliases. */
  using Self = ReinitializeLevelSetImageFilter;
  using Superclass = ImageToImageFilter< TLevelSet, TLevelSet >;
  using Pointer = SmartPointer< Self >;
  using ConstPointer = SmartPointer< const Self >;

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

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

  /** LevelSetType type alias support */
  using LevelSetType = LevelSetTypeDefault< TLevelSet >;
  using LevelSetImageType = typename LevelSetType::LevelSetImageType;
  using LevelSetPointer = typename LevelSetType::LevelSetPointer;
  using LevelSetConstPointer = typename LevelSetType::LevelSetConstPointer;
  using PixelType = typename LevelSetType::PixelType;
  using NodeType = typename LevelSetType::NodeType;
  using NodeContainer = typename LevelSetType::NodeContainer;
  using NodeContainerPointer = typename LevelSetType::NodeContainerPointer;

  /** SetDimension enumeration. */
  static constexpr unsigned int SetDimension = LevelSetType::SetDimension;

  /** Set/Get the value of the level set to be located. The default value is
   *  0. */
  itkSetMacro(LevelSetValue, double);
  itkGetConstMacro(LevelSetValue, double);

  /** Set/Get the narrowbanding flag. By default, narrowbanding is switched
   * off. */
  itkSetMacro(NarrowBanding, bool);
  itkGetConstMacro(NarrowBanding, bool);
  itkBooleanMacro(NarrowBanding);

  /** Set/Get the input narrow bandwidth. The default value is 12. */
  itkSetClampMacro( InputNarrowBandwidth, double, 0.0,
                    NumericTraits< double >::max() );
  itkGetConstMacro(InputNarrowBandwidth, double);

  /** Set/Get the output narrow bandwidth. The default value is 12. */
  itkSetClampMacro( OutputNarrowBandwidth, double, 0.0,
                    NumericTraits< double >::max() );
  itkGetConstMacro(OutputNarrowBandwidth, double);

  /** Set the bandwidth for both the input and output narrowband,
   * By default, both the input and output are set to 12. */
  void SetNarrowBandwidth(double value)
  {
    this->SetInputNarrowBandwidth(value);
    this->SetOutputNarrowBandwidth(value);
  }

  /** Set/Get the input narrowband. */
  void SetInputNarrowBand(NodeContainer *ptr);

  NodeContainerPointer GetInputNarrowBand() const
  { return m_InputNarrowBand; }

  /** Get the output narrowband. */
  NodeContainerPointer GetOutputNarrowBand() const
  { return m_OutputNarrowBand; }

#ifdef ITK_USE_CONCEPT_CHECKING
  // Begin concept checking
  itkConceptMacro( LevelSetDoubleAdditiveOperatorsCheck,
                   ( Concept::AdditiveOperators< PixelType, double > ) );
  itkConceptMacro( LevelSetOStreamWritableCheck,
                   ( Concept::OStreamWritable< PixelType > ) );
  // End concept checking
#endif

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

  /** Internal type alias. */
  using SpeedImageType = Image< float, Self::SetDimension >;
  using LocatorType = LevelSetNeighborhoodExtractor< TLevelSet >;
  using FastMarchingImageFilterType = FastMarchingImageFilter< TLevelSet, SpeedImageType >;

  void GenerateData() override;

  virtual void GenerateDataFull();

  virtual void GenerateDataNarrowBand();

  virtual void AllocateOutput();

  void GenerateInputRequestedRegion() override;

  void EnlargeOutputRequestedRegion(DataObject *) override;

  void SetOutputNarrowBand(NodeContainer *ptr)
  { m_OutputNarrowBand = ptr; }

private:
  double m_LevelSetValue;

  typename LocatorType::Pointer m_Locator;

  typename FastMarchingImageFilterType::Pointer m_Marcher;

  bool                 m_NarrowBanding;
  double               m_InputNarrowBandwidth;
  double               m_OutputNarrowBandwidth;
  NodeContainerPointer m_InputNarrowBand;
  NodeContainerPointer m_OutputNarrowBand;
};
} // namespace itk

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

#endif
