/*=========================================================================
 *
 *  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>
#include "itkExtractImageFilter.h"
#include "itkRandomImageSource.h"
#include "itkMath.h"

int
itkExtractImage3Dto2DTest(int, char *[])
{
  using Image3DType = itk::Image<unsigned char, 3>;
  using Image2DType = itk::Image<unsigned char, 2>;
  using ExtractType = itk::ExtractImageFilter<Image3DType, Image2DType>;
  using RandomImageSourceType = itk::RandomImageSource<Image3DType>;

  auto src = RandomImageSourceType::New();
  src->SetMin(0);
  src->SetMax(255);
  Image3DType::SizeType size = { { 16, 16, 16 } };
  src->SetSize(size);
  src->Update();
  Image3DType::Pointer       im3d(src->GetOutput());
  Image3DType::DirectionType dir = im3d->GetDirection();
  dir[1][1] = 0.0;
  dir[1][2] = 1.0;
  dir[2][1] = 1.0;
  dir[2][2] = 0.0;
  // change directions to
  // 1 0 0
  // 0 0 1
  // 0 1 0

  im3d->SetDirection(dir);

  auto extract = ExtractType::New();
  extract->SetDirectionCollapseToIdentity();
  Image3DType::RegionType extractRegion = im3d->GetLargestPossibleRegion();
  Image3DType::SizeType   extractSize = extractRegion.GetSize();

  extractSize[2] = 0;
  Image3DType::IndexType extractIndex;
  extractIndex[2] = extractIndex[1] = extractIndex[0] = 0;

  extract->SetInput(im3d);
  extractRegion.SetSize(extractSize);
  extractRegion.SetIndex(extractIndex);
  extract->SetExtractionRegion(extractRegion);
  extract->Update();

  Image2DType::Pointer       extractedImage = extract->GetOutput();
  Image2DType::DirectionType identity;
  identity.SetIdentity();
  if (extractedImage->GetDirection() != identity)
  {
    return EXIT_FAILURE;
  }

  // check CollapseToSubmatrix
  extract = ExtractType::New();
  extract->SetDirectionCollapseToSubmatrix();
  extractRegion = im3d->GetLargestPossibleRegion();
  extractSize = extractRegion.GetSize();

  extractSize[0] = 0;
  extractIndex[2] = extractIndex[1] = extractIndex[0] = 0;

  extract->SetInput(im3d);
  extractRegion.SetSize(extractSize);
  extractRegion.SetIndex(extractIndex);
  extract->SetExtractionRegion(extractRegion);
  extract->Update();
  // remove first column/row, should obtain :
  // 0 1
  // 1 0
  if (itk::Math::NotExactlyEquals(extract->GetOutput()->GetDirection()[0][0], 0) ||
      itk::Math::NotExactlyEquals(extract->GetOutput()->GetDirection()[1][1], 0) ||
      itk::Math::NotExactlyEquals(extract->GetOutput()->GetDirection()[0][1], 1) ||
      itk::Math::NotExactlyEquals(extract->GetOutput()->GetDirection()[1][0], 1))
  {
    return EXIT_FAILURE;
  }

  return EXIT_SUCCESS;
}
