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

// Software Guide : BeginLatex
//
// This example illustrates the use of the \doxygen{BSplineTransform}
// class for performing registration of two $3D$ images and for the case of
// multi-modality images. The image metric of choice in this case is the
// \doxygen{MattesMutualInformationImageToImageMetricv4}.
//
// \index{itk::BSplineTransform}
// \index{itk::BSplineTransform!DeformableRegistration}
// \index{itk::LBFGSBOptimizerv4}
//
// Software Guide : EndLatex

#include "itkImageRegistrationMethodv4.h"

#include "itkTimeProbesCollectorBase.h"
#include "itkMemoryProbesCollectorBase.h"


//  Software Guide : BeginLatex
//
//  The following are the most relevant headers to this example.
//
//  \index{itk::BSplineTransform!header}
//  \index{itk::LBFGSBOptimizerv4!header}
//
//  Software Guide : EndLatex

// Software Guide : BeginCodeSnippet
#include "itkBSplineTransform.h"
#include "itkLBFGSBOptimizerv4.h"
#include "itkMattesMutualInformationImageToImageMetricv4.h"
// Software Guide : EndCodeSnippet

#include "itkImageFileReader.h"
#include "itkImageFileWriter.h"

#include "itkResampleImageFilter.h"
#include "itkCastImageFilter.h"
#include "itkSquaredDifferenceImageFilter.h"

#include "itkTransformFileReader.h"

#include "itkBSplineTransformInitializer.h"
#include "itkTransformToDisplacementFieldFilter.h"

//  The following section of code implements a Command observer
//  used to monitor the evolution of the registration process.
//
#include "itkCommand.h"
class CommandIterationUpdate : public itk::Command
{
public:
  typedef  CommandIterationUpdate   Self;
  typedef  itk::Command             Superclass;
  typedef itk::SmartPointer<Self>   Pointer;
  itkNewMacro( Self );

protected:
  CommandIterationUpdate() {};

public:
  typedef itk::LBFGSBOptimizerv4    OptimizerType;
  typedef   const OptimizerType *   OptimizerPointer;

  void Execute(itk::Object *caller, const itk::EventObject & event) ITK_OVERRIDE
    {
    Execute( (const itk::Object *)caller, event);
    }

  void Execute(const itk::Object * object, const itk::EventObject & event) ITK_OVERRIDE
    {
    OptimizerPointer optimizer = static_cast< OptimizerPointer >( object );
    if( !(itk::IterationEvent().CheckEvent( &event )) )
      {
      return;
      }
    std::cout << optimizer->GetCurrentIteration() << "   ";
    std::cout << optimizer->GetCurrentMetricValue() << "   ";
    std::cout << optimizer->GetInfinityNormOfProjectedGradient() << std::endl;
    }
};


int main( int argc, char *argv[] )
{
  if( argc < 4 )
    {
    std::cerr << "Missing Parameters " << std::endl;
    std::cerr << "Usage: " << argv[0];
    std::cerr << " fixedImageFile  movingImageFile outputImagefile  ";
    std::cerr << " [differenceOutputfile] [differenceBeforeRegistration] ";
    std::cerr << " [deformationField] ";
    std::cerr << " [filenameForFinalTransformParameters] [numberOfGridNodesInOneDimension]";
    std::cerr << std::endl;
    return EXIT_FAILURE;
    }

  const    unsigned int    ImageDimension = 3;
  typedef  float           PixelType;

  typedef itk::Image< PixelType, ImageDimension >  FixedImageType;
  typedef itk::Image< PixelType, ImageDimension >  MovingImageType;


  //  Software Guide : BeginLatex
  //
  //  We instantiate now the type of the \code{BSplineTransform} using
  //  as template parameters the type for coordinates representation, the
  //  dimension of the space, and the order of the BSpline.
  //
  //  \index{BSplineTransform!New}
  //  \index{BSplineTransform!Instantiation}
  //
  //  Software Guide : EndLatex

  // Software Guide : BeginCodeSnippet
  const unsigned int SpaceDimension = ImageDimension;
  const unsigned int SplineOrder = 3;
  typedef double CoordinateRepType;

  typedef itk::BSplineTransform<
                            CoordinateRepType,
                            SpaceDimension,
                            SplineOrder >     TransformType;
  // Software Guide : EndCodeSnippet


  typedef itk::LBFGSBOptimizerv4       OptimizerType;


  typedef itk::MattesMutualInformationImageToImageMetricv4<
                                    FixedImageType,
                                    MovingImageType >    MetricType;

  typedef itk::ImageRegistrationMethodv4<
                                    FixedImageType,
                                    MovingImageType >    RegistrationType;

  MetricType::Pointer         metric        = MetricType::New();
  OptimizerType::Pointer      optimizer     = OptimizerType::New();
  RegistrationType::Pointer   registration  = RegistrationType::New();


  registration->SetMetric(        metric        );
  registration->SetOptimizer(     optimizer     );

  typedef itk::ImageFileReader< FixedImageType  > FixedImageReaderType;
  typedef itk::ImageFileReader< MovingImageType > MovingImageReaderType;

  FixedImageReaderType::Pointer  fixedImageReader  = FixedImageReaderType::New();
  MovingImageReaderType::Pointer movingImageReader = MovingImageReaderType::New();

  fixedImageReader->SetFileName(  argv[1] );
  movingImageReader->SetFileName( argv[2] );

  FixedImageType::ConstPointer fixedImage = fixedImageReader->GetOutput();

  registration->SetFixedImage(  fixedImage   );
  registration->SetMovingImage( movingImageReader->GetOutput()   );

  fixedImageReader->Update();

  //  Software Guide : BeginLatex
  //
  //  The transform object is constructed, initialized like previous example
  //  and passed to the registration method.
  //
  //  \index{itk::ImageRegistrationMethodv4!SetInitialTransform()}
  //  \index{itk::ImageRegistrationMethodv4!InPlaceOn()}
  //
  //  Software Guide : EndLatex

  // Software Guide : BeginCodeSnippet
  TransformType::Pointer  transform = TransformType::New();
  // Software Guide : EndCodeSnippet

  // Initialize the transform
  unsigned int numberOfGridNodesInOneDimension = 5;

  if( argc > 8 )
    {
    numberOfGridNodesInOneDimension = atoi( argv[8] );
    }

  typedef itk::BSplineTransformInitializer< TransformType,
                                            FixedImageType>      InitializerType;

  InitializerType::Pointer transformInitializer = InitializerType::New();

  TransformType::MeshSizeType             meshSize;
  meshSize.Fill( numberOfGridNodesInOneDimension - SplineOrder );

  transformInitializer->SetTransform( transform );
  transformInitializer->SetImage( fixedImage );
  transformInitializer->SetTransformDomainMeshSize( meshSize );
  transformInitializer->InitializeTransform();

  // Set transform to identity
  transform->SetIdentity();

  // Software Guide : BeginCodeSnippet
  registration->SetInitialTransform( transform );
  registration->InPlaceOn();
  // Software Guide : EndCodeSnippet


  //  Software Guide : BeginLatex
  //
  //  Next we set the parameters of the LBFGSB Optimizer.
  //
  //  Software Guide : EndLatex

  // Software Guide : BeginCodeSnippet
  const unsigned int numParameters = transform->GetNumberOfParameters();
  OptimizerType::BoundSelectionType boundSelect( numParameters );
  OptimizerType::BoundValueType upperBound( numParameters );
  OptimizerType::BoundValueType lowerBound( numParameters );

  boundSelect.Fill( OptimizerType::UNBOUNDED );
  upperBound.Fill( 0.0 );
  lowerBound.Fill( 0.0 );

  optimizer->SetBoundSelection( boundSelect );
  optimizer->SetUpperBound( upperBound );
  optimizer->SetLowerBound( lowerBound );

  optimizer->SetCostFunctionConvergenceFactor( 1.e7 );
  optimizer->SetGradientConvergenceTolerance( 1e-6 );
  optimizer->SetNumberOfIterations( 200 );
  optimizer->SetMaximumNumberOfFunctionEvaluations( 30 );
  optimizer->SetMaximumNumberOfCorrections( 5 );
  // Software Guide : EndCodeSnippet

  // Create the Command observer and register it with the optimizer.
  //
  CommandIterationUpdate::Pointer observer = CommandIterationUpdate::New();
  optimizer->AddObserver( itk::IterationEvent(), observer );

  //  A single level registration process is run using
  //  the shrink factor 1 and smoothing sigma 0.
  //
  const unsigned int numberOfLevels = 1;

  RegistrationType::ShrinkFactorsArrayType shrinkFactorsPerLevel;
  shrinkFactorsPerLevel.SetSize( numberOfLevels );
  shrinkFactorsPerLevel[0] = 1;

  RegistrationType::SmoothingSigmasArrayType smoothingSigmasPerLevel;
  smoothingSigmasPerLevel.SetSize( numberOfLevels );
  smoothingSigmasPerLevel[0] = 0;

  registration->SetNumberOfLevels( numberOfLevels );
  registration->SetSmoothingSigmasPerLevel( smoothingSigmasPerLevel );
  registration->SetShrinkFactorsPerLevel( shrinkFactorsPerLevel );

  //  Software Guide : BeginLatex
  //
  //  Next we set the parameters of the Mattes Mutual Information Metric.
  //
  //  Software Guide : EndLatex

  // Software Guide : BeginCodeSnippet
  metric->SetNumberOfHistogramBins( 50 );
  // Software Guide : EndCodeSnippet

  // Add time and memory probes
  itk::TimeProbesCollectorBase chronometer;
  itk::MemoryProbesCollectorBase memorymeter;

  std::cout << std::endl << "Starting Registration" << std::endl;

  try
    {
    memorymeter.Start( "Registration" );
    chronometer.Start( "Registration" );

    registration->Update();

    chronometer.Stop( "Registration" );
    memorymeter.Stop( "Registration" );

    std::cout << "Optimizer stop condition = "
              << registration->GetOptimizer()->GetStopConditionDescription()
              << std::endl;
    }
  catch( itk::ExceptionObject & err )
    {
    std::cerr << "ExceptionObject caught !" << std::endl;
    std::cerr << err << std::endl;
    return EXIT_FAILURE;
    }

  // Report the time and memory taken by the registration
  chronometer.Report( std::cout );
  memorymeter.Report( std::cout );

  OptimizerType::ParametersType finalParameters =
                                      transform->GetParameters();

  std::cout << "Last Transform Parameters" << std::endl;
  std::cout << finalParameters << std::endl;

  // Finally we use the last transform in order to resample the image.
  //
  typedef itk::ResampleImageFilter<
                            MovingImageType,
                            FixedImageType >    ResampleFilterType;

  ResampleFilterType::Pointer resample = ResampleFilterType::New();

  resample->SetTransform( transform );
  resample->SetInput( movingImageReader->GetOutput() );

  resample->SetSize(    fixedImage->GetLargestPossibleRegion().GetSize() );
  resample->SetOutputOrigin(  fixedImage->GetOrigin() );
  resample->SetOutputSpacing( fixedImage->GetSpacing() );
  resample->SetOutputDirection( fixedImage->GetDirection() );

  // This value is set to zero in order to make easier to perform
  // regression testing in this example. However, for didactic
  // exercise it will be better to set it to a medium gray value
  // such as 100 or 128.
  resample->SetDefaultPixelValue( 0 );

  typedef  signed short  OutputPixelType;

  typedef itk::Image< OutputPixelType, ImageDimension > OutputImageType;

  typedef itk::CastImageFilter<
                        FixedImageType,
                        OutputImageType > CastFilterType;

  typedef itk::ImageFileWriter< OutputImageType >  WriterType;


  WriterType::Pointer      writer =  WriterType::New();
  CastFilterType::Pointer  caster =  CastFilterType::New();


  writer->SetFileName( argv[3] );


  caster->SetInput( resample->GetOutput() );
  writer->SetInput( caster->GetOutput()   );


  try
    {
    writer->Update();
    }
  catch( itk::ExceptionObject & err )
    {
    std::cerr << "ExceptionObject caught !" << std::endl;
    std::cerr << err << std::endl;
    return EXIT_FAILURE;
    }

  typedef itk::SquaredDifferenceImageFilter<
                                  FixedImageType,
                                  FixedImageType,
                                  OutputImageType > DifferenceFilterType;

  DifferenceFilterType::Pointer difference = DifferenceFilterType::New();

  WriterType::Pointer writer2 = WriterType::New();
  writer2->SetInput( difference->GetOutput() );


  // Compute the difference image between the
  // fixed and resampled moving image.
  if( argc > 4 )
    {
    difference->SetInput1( fixedImageReader->GetOutput() );
    difference->SetInput2( resample->GetOutput() );
    writer2->SetFileName( argv[4] );
    try
      {
      writer2->Update();
      }
    catch( itk::ExceptionObject & err )
      {
      std::cerr << "ExceptionObject caught !" << std::endl;
      std::cerr << err << std::endl;
      return EXIT_FAILURE;
      }
    }


  // Compute the difference image between the
  // fixed and moving image before registration.
  if( argc > 5 )
    {
    writer2->SetFileName( argv[5] );
    difference->SetInput1( fixedImageReader->GetOutput() );
    difference->SetInput2( movingImageReader->GetOutput() );
    try
      {
      writer2->Update();
      }
    catch( itk::ExceptionObject & err )
      {
      std::cerr << "ExceptionObject caught !" << std::endl;
      std::cerr << err << std::endl;
      return EXIT_FAILURE;
      }
    }

  // Generate the explicit deformation field resulting from
  // the registration.
  if( argc > 6 )
    {
    typedef itk::Vector< float, ImageDimension >          VectorPixelType;
    typedef itk::Image< VectorPixelType, ImageDimension > DisplacementFieldImageType;

    typedef itk::TransformToDisplacementFieldFilter<
                          DisplacementFieldImageType,
                          CoordinateRepType >             DisplacementFieldGeneratorType;

    /** Create an setup displacement field generator. */
    DisplacementFieldGeneratorType::Pointer dispfieldGenerator =
                                                    DisplacementFieldGeneratorType::New();
    dispfieldGenerator->UseReferenceImageOn();
    dispfieldGenerator->SetReferenceImage( fixedImage );
    dispfieldGenerator->SetTransform( transform );
    try
      {
      dispfieldGenerator->Update();
      }
    catch ( itk::ExceptionObject & err )
      {
      std::cerr << "Exception detected while generating deformation field";
      std::cerr << " : "  << err << std::endl;
      return EXIT_FAILURE;
      }

    typedef itk::ImageFileWriter< DisplacementFieldImageType >  FieldWriterType;
    FieldWriterType::Pointer fieldWriter = FieldWriterType::New();

    fieldWriter->SetInput( dispfieldGenerator->GetOutput() );

    fieldWriter->SetFileName( argv[6] );
    try
      {
      fieldWriter->Update();
      }
    catch( itk::ExceptionObject & excp )
      {
      std::cerr << "Exception thrown " << std::endl;
      std::cerr << excp << std::endl;
      return EXIT_FAILURE;
      }
    }

  // Optionally, save the transform parameters in a file
  if( argc > 7 )
    {
    std::ofstream parametersFile;
    parametersFile.open( argv[7] );
    parametersFile << finalParameters << std::endl;
    parametersFile.close();
    }

  return EXIT_SUCCESS;
}