/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/
/*=========================================================================
 *
 *  Portions of this file are subject to the VTK Toolkit Version 3 copyright.
 *
 *  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
 *
 *  For complete copyright, license and disclaimer of warranty information
 *  please refer to the NOTICE file at the top of the ITK source tree.
 *
 *=========================================================================*/
#ifndef itkIntensityWindowingImageFilter_hxx
#define itkIntensityWindowingImageFilter_hxx

#include "itkMinimumMaximumImageCalculator.h"
#include <algorithm> // For min.

namespace itk
{

template <typename TInputImage, typename TOutputImage>
IntensityWindowingImageFilter<TInputImage, TOutputImage>::IntensityWindowingImageFilter()
  : m_Scale(1.0)
  , m_Shift(0.0)
  , m_WindowMinimum(NumericTraits<InputPixelType>::NonpositiveMin())
  , m_WindowMaximum(NumericTraits<InputPixelType>::max())
  , m_OutputMinimum(NumericTraits<OutputPixelType>::NonpositiveMin())
  , m_OutputMaximum(NumericTraits<OutputPixelType>::max())
{}

template <typename TInputImage, typename TOutputImage>
void
IntensityWindowingImageFilter<TInputImage, TOutputImage>::SetWindowLevel(const InputPixelType & window,
                                                                         const InputPixelType & level)
{
  using InputRealType = typename NumericTraits<InputPixelType>::RealType;

  InputRealType tmp1 = static_cast<InputRealType>(level) - (static_cast<InputRealType>(window) / 2.0);
  if (tmp1 < NumericTraits<InputPixelType>::NonpositiveMin())
  {
    tmp1 = 0.0;
  }

  InputRealType tmp2 = static_cast<InputRealType>(level) + (static_cast<InputRealType>(window) / 2.0);
  tmp2 = std::min<InputRealType>(tmp2, NumericTraits<InputPixelType>::max());

  this->m_WindowMinimum = static_cast<InputPixelType>(tmp1);
  this->m_WindowMaximum = static_cast<InputPixelType>(tmp2);
}

template <typename TInputImage, typename TOutputImage>
auto
IntensityWindowingImageFilter<TInputImage, TOutputImage>::GetWindow() const -> InputPixelType
{
  return this->m_WindowMaximum - this->m_WindowMinimum;
}

template <typename TInputImage, typename TOutputImage>
auto
IntensityWindowingImageFilter<TInputImage, TOutputImage>::GetLevel() const -> InputPixelType
{
  return (this->m_WindowMaximum + this->m_WindowMinimum) / 2;
}

template <typename TInputImage, typename TOutputImage>
void
IntensityWindowingImageFilter<TInputImage, TOutputImage>::BeforeThreadedGenerateData()
{
  this->m_Scale = (static_cast<RealType>(this->m_OutputMaximum) - static_cast<RealType>(this->m_OutputMinimum)) /
                  (static_cast<RealType>(this->m_WindowMaximum) - static_cast<RealType>(this->m_WindowMinimum));

  this->m_Shift =
    static_cast<RealType>(this->m_OutputMinimum) - static_cast<RealType>(this->m_WindowMinimum) * this->m_Scale;

  // set up the functor values
  this->GetFunctor().SetOutputMinimum(this->m_OutputMinimum);
  this->GetFunctor().SetOutputMaximum(this->m_OutputMaximum);

  this->GetFunctor().SetWindowMinimum(this->m_WindowMinimum);
  this->GetFunctor().SetWindowMaximum(this->m_WindowMaximum);

  this->GetFunctor().SetFactor(this->m_Scale);
  this->GetFunctor().SetOffset(this->m_Shift);
}


template <typename TInputImage, typename TOutputImage>
void
IntensityWindowingImageFilter<TInputImage, TOutputImage>::PrintSelf(std::ostream & os, Indent indent) const
{
  Superclass::PrintSelf(os, indent);

  os << indent
     << "Output Minimum: " << static_cast<typename NumericTraits<OutputPixelType>::PrintType>(this->m_OutputMinimum)
     << std::endl;
  os << indent
     << "Output Maximum: " << static_cast<typename NumericTraits<OutputPixelType>::PrintType>(this->m_OutputMaximum)
     << std::endl;
  os << indent
     << "Window Minimum: " << static_cast<typename NumericTraits<InputPixelType>::PrintType>(this->m_WindowMinimum)
     << std::endl;
  os << indent
     << "Window Maximum: " << static_cast<typename NumericTraits<InputPixelType>::PrintType>(this->m_WindowMaximum)
     << std::endl;
  os << indent << "Scale Factor: " << static_cast<typename NumericTraits<RealType>::PrintType>(this->m_Scale)
     << std::endl;
  os << indent << "Shift offset: " << static_cast<typename NumericTraits<RealType>::PrintType>(this->m_Shift)
     << std::endl;
}

} // end namespace itk

#endif
