/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/
#ifndef itkAttributeRelabelLabelMapFilter_hxx
#define itkAttributeRelabelLabelMapFilter_hxx

#include "itkProgressReporter.h"


namespace itk
{

template <typename TImage, typename TAttributeAccessor>
AttributeRelabelLabelMapFilter<TImage, TAttributeAccessor>::AttributeRelabelLabelMapFilter()
{
  m_ReverseOrdering = false;
}


template <typename TImage, typename TAttributeAccessor>
void
AttributeRelabelLabelMapFilter<TImage, TAttributeAccessor>::GenerateData()
{
  // Allocate the output
  this->AllocateOutputs();

  ImageType * output = this->GetOutput();

  using VectorType = typename std::vector<typename LabelObjectType::Pointer>;

  ProgressReporter progress(this, 0, 2 * output->GetNumberOfLabelObjects());

  // get the label objects in a vector, so they can be sorted
  VectorType labelObjects;
  labelObjects.reserve(output->GetNumberOfLabelObjects());
  for (typename ImageType::Iterator it(output); !it.IsAtEnd(); ++it)
  {
    labelObjects.push_back(it.GetLabelObject());
    progress.CompletedPixel();
  }

  // instantiate the comparator and sort the vector
  if (m_ReverseOrdering)
  {
    ReverseComparator comparator;
    std::sort(labelObjects.begin(), labelObjects.end(), comparator);
  }
  else
  {
    Comparator comparator;
    std::sort(labelObjects.begin(), labelObjects.end(), comparator);
  }
  //   progress.CompletedPixel();

  // and put back the objects in the map
  output->ClearLabels();
  unsigned int label = 0;
  for (typename VectorType::const_iterator it = labelObjects.begin(); it != labelObjects.end(); ++it)
  {
    // avoid the background label if it is used
    if (label == output->GetBackgroundValue())
    {
      ++label;
    }
    (*it)->SetLabel(label);
    output->AddLabelObject(*it);

    // go to the nex label
    ++label;
    progress.CompletedPixel();
  }
}


template <typename TImage, typename TAttributeAccessor>
void
AttributeRelabelLabelMapFilter<TImage, TAttributeAccessor>::PrintSelf(std::ostream & os, Indent indent) const
{
  Superclass::PrintSelf(os, indent);

  os << indent << "ReverseOrdering: " << m_ReverseOrdering << std::endl;
}

} // end namespace itk
#endif
