/*=========================================================================
 *
 *  Copyright UMC Utrecht and contributors
 *
 *  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.
 *
 *=========================================================================*/
#ifndef itkDeformationFieldInterpolatingTransform_h
#define itkDeformationFieldInterpolatingTransform_h

#include <iostream>
#include "itkAdvancedTransform.h"
#include "itkMacro.h"
#include "itkImage.h"
#include "itkVectorInterpolateImageFunction.h"
#include "itkVectorNearestNeighborInterpolateImageFunction.h"

namespace itk
{

/** \brief Transform that interpolates a given deformation field
 *
 * A simple transform that allows the user to set a deformation field.
 * TransformPoint adds the displacement to the input point.
 * This transform does not support optimizers. Its Set/GetParameters
 * is not implemented. DO NOT USE IT FOR REGISTRATION.
 * You may set your own interpolator!
 *
 * \ingroup Transforms
 */

template <class TScalarType = double,   // Data type for scalars (float or double)
          unsigned int NDimensions = 3, // Number of input dimensions
          class TComponentType = double>
// ComponentType of the deformation field
class ITK_TEMPLATE_EXPORT DeformationFieldInterpolatingTransform
  : public AdvancedTransform<TScalarType, NDimensions, NDimensions>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(DeformationFieldInterpolatingTransform);

  /** Standard class typedefs. */
  using Self = DeformationFieldInterpolatingTransform;
  using Superclass = AdvancedTransform<TScalarType, NDimensions, NDimensions>;
  using Pointer = SmartPointer<Self>;
  using ConstPointer = SmartPointer<const Self>;

  /** New macro for creation of through the object factory.*/
  itkNewMacro(Self);

  /** Run-time type information (and related methods). */
  itkTypeMacro(DeformationFieldInterpolatingTransform, AdvancedTransform);

  /** Dimension of the domain spaces. */
  itkStaticConstMacro(InputSpaceDimension, unsigned int, Superclass::InputSpaceDimension);
  itkStaticConstMacro(OutputSpaceDimension, unsigned int, Superclass::OutputSpaceDimension);

  /** Superclass typedefs */
  using typename Superclass::ScalarType;
  using typename Superclass::ParametersType;
  using typename Superclass::NumberOfParametersType;
  using typename Superclass::JacobianType;
  using typename Superclass::InputVectorType;
  using typename Superclass::OutputVectorType;
  using typename Superclass::InputCovariantVectorType;
  using typename Superclass::OutputCovariantVectorType;
  using typename Superclass::InputVnlVectorType;
  using typename Superclass::OutputVnlVectorType;
  using typename Superclass::InputPointType;
  using typename Superclass::OutputPointType;
  using typename Superclass::NonZeroJacobianIndicesType;
  using typename Superclass::SpatialHessianType;
  using typename Superclass::SpatialJacobianType;
  using typename Superclass::JacobianOfSpatialHessianType;
  using typename Superclass::JacobianOfSpatialJacobianType;

  using typename Superclass::InternalMatrixType;

  using DeformationFieldComponentType = TComponentType;
  using DeformationFieldVectorType = Vector<DeformationFieldComponentType, Self::OutputSpaceDimension>;
  using DeformationFieldType = Image<DeformationFieldVectorType, Self::InputSpaceDimension>;
  using DeformationFieldPointer = typename DeformationFieldType::Pointer;

  using DeformationFieldInterpolatorType = VectorInterpolateImageFunction<DeformationFieldType, ScalarType>;
  using DeformationFieldInterpolatorPointer = typename DeformationFieldInterpolatorType::Pointer;
  using DefaultDeformationFieldInterpolatorType =
    VectorNearestNeighborInterpolateImageFunction<DeformationFieldType, ScalarType>;

  /** Set the transformation parameters is not supported.
   * Use SetDeformationField() instead
   */
  void
  SetParameters(const ParametersType &) override
  {
    itkExceptionMacro("ERROR: SetParameters() is not implemented for DeformationFieldInterpolatingTransform.\n"
                      << "Use SetDeformationField() instead.\n"
                      << "Note that this transform is NOT suited for image registration.\n"
                      << "Just use it as an (initial) fixed transform that is not optimized.");
  }


  /** Set the fixed parameters. */
  void
  SetFixedParameters(const ParametersType &) override
  {
    // This transform has no fixed parameters.
  }


  /** Get the Fixed Parameters. */
  const ParametersType &
  GetFixedParameters() const override
  {
    // This transform has no fixed parameters.
    return this->m_FixedParameters;
  }


  /** Transform a point. This method adds a displacement to a given point,
   * returning the transformed point.
   */
  OutputPointType
  TransformPoint(const InputPointType & point) const override;

  /** These vector transforms are not implemented for this transform. */
  OutputVectorType
  TransformVector(const InputVectorType &) const override
  {
    itkExceptionMacro(
      "TransformVector(const InputVectorType &) is not implemented for DeformationFieldInterpolatingTransform");
  }


  OutputVnlVectorType
  TransformVector(const InputVnlVectorType &) const override
  {
    itkExceptionMacro(
      "TransformVector(const InputVnlVectorType &) is not implemented for DeformationFieldInterpolatingTransform");
  }


  OutputCovariantVectorType
  TransformCovariantVector(const InputCovariantVectorType &) const override
  {
    itkExceptionMacro("TransformCovariantVector(const InputCovariantVectorType &) is not implemented for "
                      "DeformationFieldInterpolatingTransform");
  }


  /** Make this an identity transform ( the deformation field is replaced
   * by a zero deformation field */
  void
  SetIdentity();

  /** Set/Get the deformation field that defines the displacements */
  virtual void
  SetDeformationField(DeformationFieldType * _arg);

  itkGetModifiableObjectMacro(DeformationField, DeformationFieldType);

  /** Set/Get the deformation field interpolator */
  virtual void
  SetDeformationFieldInterpolator(DeformationFieldInterpolatorType * _arg);

  itkGetModifiableObjectMacro(DeformationFieldInterpolator, DeformationFieldInterpolatorType);

  bool
  IsLinear() const override
  {
    return false;
  }

  /** Must be provided. */
  void
  GetJacobian(const InputPointType &, JacobianType &, NonZeroJacobianIndicesType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetSpatialJacobian(const InputPointType &, SpatialJacobianType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetSpatialHessian(const InputPointType &, SpatialHessianType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetJacobianOfSpatialJacobian(const InputPointType &,
                               JacobianOfSpatialJacobianType &,
                               NonZeroJacobianIndicesType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetJacobianOfSpatialJacobian(const InputPointType &,
                               SpatialJacobianType &,
                               JacobianOfSpatialJacobianType &,
                               NonZeroJacobianIndicesType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetJacobianOfSpatialHessian(const InputPointType &,
                              JacobianOfSpatialHessianType &,
                              NonZeroJacobianIndicesType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


  void
  GetJacobianOfSpatialHessian(const InputPointType &,
                              SpatialHessianType &,
                              JacobianOfSpatialHessianType &,
                              NonZeroJacobianIndicesType &) const override
  {
    itkExceptionMacro("Not implemented for DeformationFieldInterpolatingTransform");
  }


protected:
  DeformationFieldInterpolatingTransform();
  ~DeformationFieldInterpolatingTransform() override = default;

  /** Typedef which is used internally */
  using InputContinuousIndexType = typename DeformationFieldInterpolatorType::ContinuousIndexType;
  using InterpolatorOutputType = typename DeformationFieldInterpolatorType::OutputType;

  /** Print contents of an DeformationFieldInterpolatingTransform. */
  void
  PrintSelf(std::ostream & os, Indent indent) const override;

  DeformationFieldPointer             m_DeformationField{};
  DeformationFieldPointer             m_ZeroDeformationField{};
  DeformationFieldInterpolatorPointer m_DeformationFieldInterpolator{};

private:
  // Private using-declarations, to avoid `-Woverloaded-virtual` warnings from GCC (GCC 11.4).
  using Superclass::TransformCovariantVector;
  using Superclass::TransformVector;
};

} // namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#  include "itkDeformationFieldInterpolatingTransform.hxx"
#endif

#endif /* itkDeformationFieldInterpolatingTransform_h */