/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  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
 *
 *         https://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.
 *
 *=========================================================================*/

#include <iostream>

// Native ITK stuff
#include "itkImageRegionIterator.h"

// Spatial function stuff
#include "itkSphereSpatialFunction.h"
#include "itkFloodFilledSpatialFunctionConditionalIterator.h"

int
itkFloodFillIteratorTest(int, char *[])
{
  constexpr unsigned int dim{ 3 };

  // Image type alias
  using TImageType = itk::Image<int, dim>;

  //-----------------Create a new input image--------------------
  // Image size and spacing parameters
  TImageType::SizeValueType    sourceImageSize[] = { 20, 20, 20 };
  TImageType::SpacingValueType sourceImageSpacing[] = { 1.0, 1.0, 1.0 };
  TImageType::PointValueType   sourceImageOrigin[] = { 0, 0, 0 };

  // Creates the sourceImage (but doesn't set the size or allocate memory)
  auto sourceImage = TImageType::New();
  sourceImage->SetOrigin(sourceImageOrigin);
  sourceImage->SetSpacing(sourceImageSpacing);

  std::cout << "New sourceImage created" << std::endl;

  //-----The following block allocates the sourceImage-----

  // Create a size object native to the sourceImage type
  TImageType::SizeType sourceImageSizeObject;
  // Set the size object to the array defined earlier
  sourceImageSizeObject.SetSize(sourceImageSize);
  // Create a region object native to the sourceImage type
  TImageType::RegionType largestPossibleRegion;
  // Resize the region
  largestPossibleRegion.SetSize(sourceImageSizeObject);
  // Set the largest legal region size (i.e. the size of the whole sourceImage), the buffered, and
  // the requested region to what we just defined.
  sourceImage->SetRegions(largestPossibleRegion);
  // Now allocate memory for the sourceImage
  sourceImage->AllocateInitialized();

  std::cout << "New sourceImage allocated" << std::endl;

  //---------Create and initialize a spatial function-----------

  using TFunctionType = itk::SphereSpatialFunction<dim>;
  using TFunctionPositionType = TFunctionType::InputType;

  // Create and initialize a new sphere function

  auto spatialFunc = TFunctionType::New();
  spatialFunc->SetRadius(5);

  TFunctionPositionType center;
  center[0] = 10;
  center[1] = 10;
  center[2] = 10;
  spatialFunc->SetCenter(center);

  std::cout << "Sphere spatial function created" << std::endl;

  //---------Create and initialize a spatial function iterator-----------
  TImageType::IndexType                seedPos;
  constexpr TImageType::IndexValueType pos[]{ 10, 10, 10 };
  seedPos.SetIndex(pos);

  using TItType = itk::FloodFilledSpatialFunctionConditionalIterator<TImageType, TFunctionType>;
  TItType sfi(sourceImage, spatialFunc, seedPos);

  // Iterate through the entire image and set interior pixels to 255
  for (; !(sfi.IsAtEnd()); ++sfi)
  {

    std::cout << sfi.GetIndex() << ": " << sfi.Get() << std::endl;
    sfi.Set(255);
  }

  std::cout << "Spatial function iterator created, sphere drawn" << std::endl;

  return EXIT_SUCCESS;
}
