/*=========================================================================
 *
 *  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 itkFloodFilledSpatialFunctionConditionalConstIterator_h
#define itkFloodFilledSpatialFunctionConditionalConstIterator_h

#include "itkFloodFilledFunctionConditionalConstIterator.h"

namespace itk
{
/**
 * \class FloodFilledSpatialFunctionConditionalConstIterator
 * \brief Iterates over a flood-filled spatial function with read-only access
 *        to pixels.
 *
 * \ingroup ImageIterators
 *
 * \ingroup ITKCommon
 */
template< typename TImage, typename TFunction >
class ITK_TEMPLATE_EXPORT FloodFilledSpatialFunctionConditionalConstIterator:public FloodFilledFunctionConditionalConstIterator<
    TImage, TFunction >
{
public:
  /** Standard class type aliases. */
  using Self = FloodFilledSpatialFunctionConditionalConstIterator;
  using Superclass = FloodFilledFunctionConditionalConstIterator< TImage, TFunction >;

  /** Type of function */
  using FunctionType = typename Superclass::FunctionType;

  /** Type of vector used to store location info in the spatial function */
  using FunctionInputType = typename Superclass::FunctionInputType;

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

  /** Index ContainerType. */
  using SeedsContainerType = typename Superclass::SeedsContainerType;

  /** Size type alias support */
  using SizeType = typename Superclass::SizeType;

  /** Region type alias support */
  using RegionType = typename Superclass::RegionType;

  /** Image type alias support */
  using ImageType = typename Superclass::ImageType;

  /** Internal Pixel Type */
  using InternalPixelType = typename Superclass::InternalPixelType;

  /** External Pixel Type */
  using PixelType = typename Superclass::PixelType;

  /** Constructor establishes an iterator to walk a particular image and a
   * particular region of that image. This version of the constructor uses
   * an explicit seed pixel for the flood fill, the "startIndex" */
  FloodFilledSpatialFunctionConditionalConstIterator(const ImageType *imagePtr,
                                                     FunctionType *fnPtr,
                                                     IndexType startIndex);

  /** Constructor establishes an iterator to walk a particular image and a
   * particular region of that image. This version of the constructor
   * should be used when the seed pixel is unknown. */
  FloodFilledSpatialFunctionConditionalConstIterator(const ImageType *imagePtr,
                                                     FunctionType *fnPtr);
  /** Default Destructor. */
  ~FloodFilledSpatialFunctionConditionalConstIterator() override = default;

  /** Compute whether the index of interest should be included in the flood */
  bool IsPixelIncluded(const IndexType & index) const override;

  /** Set the inclusion strategy to origin */
  void SetOriginInclusionStrategy() { m_InclusionStrategy = 0; }

  /** Set the inclusion strategy to center */
  void SetCenterInclusionStrategy() { m_InclusionStrategy = 1; }

  /** Set the inclusion strategy to complete */
  void SetCompleteInclusionStrategy() { m_InclusionStrategy = 2; }

  /** Set the inclusion strategy to intersect */
  void SetIntersectInclusionStrategy() { m_InclusionStrategy = 3; }

protected: //made protected so other iterators can access

  /** How the pixel (index) is examined in order to decide whether or not
 * it's included. The strategies are:
 * 0) Origin: if the origin of the pixel in physical space is inside the function,
 * then the pixel is inside the function
 * 1) Center: if the center of a pixel, in physical space, is inside the function,
 * then the pixel is inside the function
 * 2) Complete: if all of the corners of the pixel in physical space are inside the function,
 * then the pixel is inside the function
 * 3) Intersect: if any of the corners of the pixel in physical space are inside the function,
 * then the pixel is inside the function */

  unsigned char m_InclusionStrategy;
};
} // end namespace itk

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

#endif
