/*
 * 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 otbMultiChannelExtractROI_hxx
#define otbMultiChannelExtractROI_hxx

#include "otbMultiChannelExtractROI.h"

#include "itkImageRegionIterator.h"
#include "itkObjectFactory.h"
#include "itkExtractImageFilterRegionCopier.h"
#include "itkProgressReporter.h"

namespace otb
{

/**
 *
 */
template <class TInputPixelType, class TOutputPixelType>
MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::MultiChannelExtractROI()
  : ExtractROIBase<VectorImage<TInputPixelType, 2>, VectorImage<TOutputPixelType, 2>>(), m_FirstChannel(0), m_LastChannel(0), m_ChannelsKind(0)
{
  ClearChannels();
}

/**
 *
 */
template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::SetChannel(unsigned int channel)
{
  if (m_ChannelsKind == 1)
  {
    itkExceptionMacro(<< "m_Channels already set using channels interval.");
  }
  m_Channels.push_back(channel);
  if (m_ChannelsKind == 0)
  {
    m_ChannelsKind = 2;
  }
  this->Modified();
}

template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::SetFirstChannel(unsigned int id)
{
  if (m_ChannelsKind == 2)
  {
    itkExceptionMacro(<< "m_Channels already set using SetChannels method.");
  }
  m_FirstChannel = id;
  if (m_ChannelsKind == 0)
  {
    m_ChannelsKind = 1;
  }
  this->Modified();
}

template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::SetLastChannel(unsigned int id)
{
  if (m_ChannelsKind == 2)
  {
    itkExceptionMacro(<< "m_Channels already set using SetChannels method.");
  }
  m_LastChannel = id;
  if (m_ChannelsKind == 0)
  {
    m_ChannelsKind = 1;
  }
  this->Modified();
}

/**
 *
 */
template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::ClearChannels(void)
{
  m_FirstChannel = 0;
  m_LastChannel  = 0;
  m_Channels.clear();
  m_ChannelsKind = 0;
  m_ChannelsWorks.clear();
}

/**
 *
 */
template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::PrintSelf(std::ostream& os, itk::Indent indent) const
{
  Superclass::PrintSelf(os, indent);
}

template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::ChannelsReInitialization()
{
  // The following conditions can be gathered but we'd loose in comprehension
  m_ChannelsWorks.clear();
  // First passage in the method:
  if (m_Channels.empty() == true)
  {
    // - User SetFirst/LastChannel()
    if (m_ChannelsKind == 1)
    {
      this->SetChannelsWorkWithLimits();
    }
    else
    {
      // - User called SetChannels()
      if (m_Channels.empty() == true && m_ChannelsKind == 2)
      {
        m_ChannelsWorks = m_Channels;
      }
    }
  }
  // Second passage in the method: Update already donne
  else
  {
    // - User SetFirst/LastChannel()
    if (m_ChannelsKind == 1)
    {
      m_Channels.clear();
      this->SetChannelsWorkWithLimits();
    }
    else
    {
      // - User called SetChannels()
      if (m_ChannelsKind == 2)
      {
        m_ChannelsWorks = m_Channels;
      }
    }
  }
}

template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::SetChannelsWorkWithLimits()
{
  if ((m_FirstChannel == 0) || (m_LastChannel == 0))
  {
    itkExceptionMacro(<< "otb::ExtractImageFilter::GenerateOutputInformation "
                      << "Channels must reside into [1...] " << typeid(itk::ImageBase<InputImageDimension>*).name());
  }
  if (m_FirstChannel > m_LastChannel)
  {
    itkExceptionMacro(<< "otb::ExtractImageFilter::GenerateOutputInformation "
                      << "FirstChannel is greater than LastChannel" << typeid(itk::ImageBase<InputImageDimension>*).name());
  }

  for (unsigned int channel = m_FirstChannel; channel <= m_LastChannel; channel++)
  {
    m_ChannelsWorks.push_back(channel);
  }

  m_Channels = m_ChannelsWorks;
}

/**
 * ExtractImageFilter can produce an image which is a different resolution
 * than its input image.  As such, ExtractImageFilter needs to provide an
 * implementation for GenerateOutputInformation() in order to inform
 * the pipeline execution model.  The original documentation of this
 * method is below.
 *
 * \sa ProcessObject::GenerateOutputInformaton()
 */
template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::GenerateOutputInformation()
{
  // Call to the superclass implementation
  Superclass::GenerateOutputInformation();
  this->ChannelsReInitialization();

  typename Superclass::InputImageConstPointer inputPtr  = this->GetInput();
  typename Superclass::OutputImagePointer     outputPtr = this->GetOutput();

  unsigned int nbComponentsPerPixel = inputPtr->GetNumberOfComponentsPerPixel();
  if (m_ChannelsKind != 0)
  {
    // Test if the asked channels index exists in the input image
    ChannelsType m_BadChannels;
    m_BadChannels.clear();
    for (unsigned int i = 0; i < m_ChannelsWorks.size(); ++i)
    {
      if ((m_ChannelsWorks[i] < 1) || (m_ChannelsWorks[i] > nbComponentsPerPixel))
      {
        bool isInsideBadChannels = false;
        for (unsigned int j = 0; j < m_BadChannels.size(); ++j)
        {
          if (m_BadChannels[j] == m_ChannelsWorks[i])
            isInsideBadChannels = true;
        }
        if (!isInsideBadChannels)
          m_BadChannels.push_back(m_ChannelsWorks[i]);
      }
    }
    if (m_BadChannels.empty() == false)
    {
      std::ostringstream oss;
      oss << "otb::ExtractImageFilter::GenerateOutputInformation : ";
      oss << "Channel(s) [ ";
      for (unsigned int i = 0; i < m_BadChannels.size(); ++i)
      {
        oss << m_BadChannels[i] << " ";
      }
      oss << "] not authorized.";
      oss << " Each channel index has to be in [1," << nbComponentsPerPixel << "].";
      itkExceptionMacro(<< oss.str().c_str());
    }
    nbComponentsPerPixel = m_ChannelsWorks.size();
  }

  // initialize the number of channels of the output image
  outputPtr->SetNumberOfComponentsPerPixel(nbComponentsPerPixel);
}

template <class TInputPixelType, class TOutputPixelType>
void MultiChannelExtractROI<TInputPixelType, TOutputPixelType>::ThreadedGenerateData(const OutputImageRegionType& outputRegionForThread,
                                                                                     itk::ThreadIdType threadId)
{
  itkDebugMacro(<< "Actually executing");
  // Get the input and output pointers
  typename Superclass::InputImageConstPointer inputPtr  = this->GetInput();
  typename Superclass::OutputImagePointer     outputPtr = this->GetOutput();

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

  // Define the portion of the input to walk for this thread
  InputImageRegionType inputRegionForThread;
  this->CallCopyOutputRegionToInputRegion(inputRegionForThread, outputRegionForThread);

  // Define the iterators.
  typedef itk::ImageRegionIterator<OutputImageType>     OutputIterator;
  typedef itk::ImageRegionConstIterator<InputImageType> InputIterator;

  OutputIterator outIt(outputPtr, outputRegionForThread);
  InputIterator  inIt(inputPtr, inputRegionForThread);

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

  // if default behaviour
  if (m_ChannelsKind == 0)
  {
    // walk the output region, and sample the input image
    while (!outIt.IsAtEnd())
    {
      outIt.Set(inIt.Get());
      ++outIt;
      ++inIt;
      progress.CompletedPixel();
    }
  }
  // Specific behaviour
  else
  {
    // for each channel to process
    unsigned int channelIn(0);
    unsigned int channelOut(0);
    unsigned int nbChannels(0);

    InputImagePixelType pixelInput;
    while (!outIt.IsAtEnd())
    {
      OutputImagePixelType pixelOutput;
      pixelOutput.Reserve(outputPtr->GetVectorLength());
      pixelInput = inIt.Get();
      channelOut = 0;
      for (nbChannels = 0; nbChannels < m_ChannelsWorks.size(); ++nbChannels)
      {
        channelIn               = m_ChannelsWorks[nbChannels] - 1;
        pixelOutput[channelOut] = static_cast<OutputValueType>(pixelInput[channelIn]);
        channelOut++;
      }
      outIt.Set(pixelOutput);
      ++outIt;
      ++inIt;
      progress.CompletedPixel();
    }
  }
}

} // end namespace otb

#endif
