/*
 * Copyright (C) 2005-2020 Centre National d'Etudes Spatiales (CNES)
 *
 * This file is part of Orfeo Toolbox
 *
 *     https://www.orfeo-toolbox.org/
 *
 * 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
 *
 * 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 otbMatrixImageFilter_hxx
#define otbMatrixImageFilter_hxx

#include "otbMatrixImageFilter.h"
#include "itkImageRegionIterator.h"
#include "itkProgressReporter.h"

namespace otb
{

/**
 *
 */
template <class TInputImage, class TOutputImage, class TMatrix>
MatrixImageFilter<TInputImage, TOutputImage, TMatrix>::MatrixImageFilter() : m_MatrixByVector(false)
{
}

template <class TInputImage, class TOutputImage, class TMatrix>
void MatrixImageFilter<TInputImage, TOutputImage, TMatrix>::GenerateOutputInformation()
{
  // call the superclass' implementation of this method
  Superclass::GenerateOutputInformation();

  if (m_MatrixByVector)
  {
    if (this->GetInput()->GetNumberOfComponentsPerPixel() != m_Matrix.cols())
    {
      itkExceptionMacro("Invalid Matrix size. Number of columns must be the same as the image number of channels.");
    }

    if (m_Matrix.rows() == 0)
    {
      itkExceptionMacro("Invalid Matrix size. Number of rows can't be null.");
    }
    this->GetOutput()->SetNumberOfComponentsPerPixel(m_Matrix.rows());
  }

  if (!m_MatrixByVector)
  {
    if (this->GetInput()->GetNumberOfComponentsPerPixel() != m_Matrix.rows())
    {
      itkExceptionMacro("Invalid Matrix size. Number of rows must be the same as the image number of channels.");
    }

    if (m_Matrix.cols() == 0)
    {
      itkExceptionMacro("Invalid Matrix size. Number of columns can't be null.");
    }
    this->GetOutput()->SetNumberOfComponentsPerPixel(m_Matrix.cols());
  }
}

template <class TInputImage, class TOutputImage, class TMatrix>
void MatrixImageFilter<TInputImage, TOutputImage, TMatrix>::ThreadedGenerateData(const OutputImageRegionType& outputRegionForThread, itk::ThreadIdType threadId)
{
  // images pointer
  typename OutputImageType::Pointer     outputPtr = this->GetOutput();
  typename InputImageType::ConstPointer inputPtr  = this->GetInput();

  typename itk::ImageRegionConstIterator<InputImageType> inIt(inputPtr, outputRegionForThread);
  itk::ImageRegionIterator<OutputImageType>              outIt(outputPtr, outputRegionForThread);


  // support progress methods/callbacks
  itk::ProgressReporter progress(this, threadId, outputRegionForThread.GetNumberOfPixels());

  inIt.GoToBegin();
  outIt.GoToBegin();

  const unsigned int inSize  = m_MatrixByVector ? m_Matrix.cols() : m_Matrix.rows();
  const unsigned int outSize = m_MatrixByVector ? m_Matrix.rows() : m_Matrix.cols();

  VectorType inVect(inSize, InputRealType(0.));
  VectorType outVect(outSize, InputRealType(0.));

  while (!outIt.IsAtEnd())
  {
    const InputPixelType& inPix = inIt.Get();
    OutputPixelType       outPix;
    outPix.SetSize(outSize);

    for (unsigned int i = 0; i < inSize; ++i)
    {
      inVect[i] = static_cast<InputRealType>(inPix[i]);
    }

    outVect = m_MatrixByVector ? m_Matrix * inVect : inVect * m_Matrix;

    for (unsigned int i = 0; i < outSize; ++i)
    {
      outPix[i] = static_cast<OutputInternalPixelType>(outVect[i]);
    }
    outIt.Set(outPix);

    ++inIt;
    ++outIt;
    progress.CompletedPixel();
  }
}


/**
 * Standard "PrintSelf" method
 */
template <class TInputImage, class TOutputImage, class TMatrix>
void MatrixImageFilter<TInputImage, TOutputImage, TMatrix>::PrintSelf(std::ostream& os, itk::Indent indent) const
{
  Superclass::PrintSelf(os, indent);
  os << indent << "Matrix: " << m_Matrix << std::endl;
  os << indent << "MatrixByVector: " << m_MatrixByVector << std::endl;
}

} // end namespace otb

#endif
