/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/

#include "itkLabelVotingImageFilter.h"
#include "itkTestingMacros.h"


int itkLabelVotingImageFilterTest( int, char* [] )
{

  // Define the dimension of the images
  const unsigned int Dimension = 3;

  // Declare the pixel types of the images
  typedef unsigned int PixelType;

  // Declare the types of the images
  typedef itk::Image< PixelType, Dimension > ImageType;

  // Input data arrays for test images
  const unsigned int dataImageA[8] =
    { 0, 1, 3, 3, 4, 6, 6, 0 };
  const unsigned int dataImageB[8] =
    { 1, 1, 2, 4, 4, 5, 7, 1 };
  const unsigned int dataImageC[8] =
    { 0, 2, 2, 3, 5, 5, 6, 8 };

  // Correct combinations of input images
  const unsigned int combinationABC[8] =
    { 0, 1, 2, 3, 4, 5, 6, 9 };
  const unsigned int combinationAB[8] =
    { 8, 1, 8, 8, 4, 8, 8, 8 };
  const unsigned int combinationABundecided255[8] =
    { 255, 1, 255, 255, 4, 255, 255, 255 };

  // Declare the type of the index to access images
  typedef itk::Index< Dimension >                   IndexType;

  // Declare the type of the size
  typedef itk::Size< Dimension >                    SizeType;

  // Declare the type of the Region
  typedef itk::ImageRegion< Dimension >             RegionType;

  // Declare appropriate Iterator type for the images
  typedef itk::ImageRegionIterator< ImageType >     IteratorType;

  // Declare the type for the filter
  typedef itk::LabelVotingImageFilter< ImageType >
    LabelVotingImageFilterType;

  // Create the input images
  ImageType::Pointer inputImageA = ImageType::New();
  ImageType::Pointer inputImageB = ImageType::New();
  ImageType::Pointer inputImageC = ImageType::New();

  // Define their size, and start index
  SizeType size;
  size[0] = 2;
  size[1] = 2;
  size[2] = 2;

  IndexType start;
  start[0] = 0;
  start[1] = 0;
  start[2] = 0;

  RegionType region;
  region.SetIndex( start );
  region.SetSize( size );

  // Initialize Image A
  inputImageA->SetLargestPossibleRegion( region );
  inputImageA->SetBufferedRegion( region );
  inputImageA->SetRequestedRegion( region );
  inputImageA->Allocate();

  IteratorType it =
    IteratorType( inputImageA, inputImageA->GetBufferedRegion() );

  for( int i = 0; i < 8; ++i, ++it )
    {
    it.Set( dataImageA[i] );
    }

  // Initialize Image B
  inputImageB->SetLargestPossibleRegion( region );
  inputImageB->SetBufferedRegion( region );
  inputImageB->SetRequestedRegion( region );
  inputImageB->Allocate();

  it = IteratorType( inputImageB, inputImageB->GetBufferedRegion() );
  for( int i = 0; i < 8; ++i, ++it )
    {
    it.Set( dataImageB[i] );
    }

  // Initialize Image C
  inputImageC->SetLargestPossibleRegion( region );
  inputImageC->SetBufferedRegion( region );
  inputImageC->SetRequestedRegion( region );
  inputImageC->Allocate();

  it = IteratorType( inputImageC, inputImageC->GetBufferedRegion() );
  for( int i = 0; i < 8; ++i, ++it )
    {
    it.Set( dataImageC[i] );
    }

  // Create the LabelVoting Filter
  LabelVotingImageFilterType::Pointer labelVotingFilter =
    LabelVotingImageFilterType::New();

  EXERCISE_BASIC_OBJECT_METHODS( labelVotingFilter, LabelVotingImageFilter,
    ImageToImageFilter );


  // Test with first two input images with undecided label set to 255
  //

  // Set the first two input images
  labelVotingFilter->SetInput( 0, inputImageA );
  labelVotingFilter->SetInput( 1, inputImageB );

  // Set label for undecided pixels
  labelVotingFilter->SetLabelForUndecidedPixels( 255 );

  // Execute the filter
  labelVotingFilter->Update();

  // Get the filter output
  ImageType::Pointer outputImage = labelVotingFilter->GetOutput();

  // Compare to correct results
  it = IteratorType( outputImage, outputImage->GetBufferedRegion() );
  for( unsigned int i = 0; i < 8; ++i, ++it )
    {
    if( combinationABundecided255[i] != it.Get() )
      {
      std::cout << "Incorrect result using images A,B and undecided=255: "
                << "i = " << i
                << ", Expected = " << combinationABundecided255[i]
                << ", Received = " << it.Get() << "\n";
      return EXIT_FAILURE;
      }
    }


  // Test with first two input images
  //

  // unset undecided pixel label; reinstate automatic selection
  labelVotingFilter->UnsetLabelForUndecidedPixels();

  // Execute the filter
  labelVotingFilter->Update();

  // Get the filter output
  outputImage = labelVotingFilter->GetOutput();

  // Compare to correct results
  it = IteratorType( outputImage, outputImage->GetBufferedRegion() );
  for(unsigned int i = 0; i < 8; ++i, ++it )
    {
    if( combinationAB[i] != it.Get() )
      {
      std::cout << "Incorrect result using images A,B: i = " << i
                << ", Expected = " << combinationAB[i]
                << ", Received = " << it.Get() << "\n";
      return EXIT_FAILURE;
      }
    }


  // Test with all three input images
  //

  // Set the third input image
  labelVotingFilter->SetInput( 2, inputImageC );

  // Execute the filter
  labelVotingFilter->Update();

  // Get the filter output
  outputImage = labelVotingFilter->GetOutput();

  // Compare to correct results
  it = IteratorType( outputImage, outputImage->GetBufferedRegion() );
  for( unsigned int i = 0; i < 8; ++i, ++it )
    {
    if( combinationABC[i] != it.Get() )
      {
      std::cout << "Incorrect result using images A,B,C: i = " << i
                << ", Expected = " << combinationABC[i]
                << ", Received = " << it.Get() << "\n";
      return EXIT_FAILURE;
      }
    }

  std::cout << "Test succeeded." << std::endl;

  // All objects should be automatically destroyed at this point
  return EXIT_SUCCESS;
}