/*
 * 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 otbSarRadiometricCalibrationFunction_h
#define otbSarRadiometricCalibrationFunction_h

#include "otbSarParametricMapFunction.h"
#include "otbSarCalibrationLookupData.h"

#include "otbS1ThermalNoiseLookupData.h"

#include "otbMath.h"
namespace otb
{
/**
 * \class SarRadiometricCalibrationFunction
 * \brief Calculate the backscatter for the given pixel
 *
 * Calculate the backscatter for the given pixel
 *
 * If called with a ContinuousIndex or Point, the calculation is performed
 * at the nearest neighbor.
 *
 * This class is templated over the input image type and the
 * coordinate representation type (e.g. float or double ).
 *
 * \ingroup ImageFunctions
 *
 * \ingroup OTBSARCalibration
 */

template <class TInputImage, class TCoordRep = float>
class ITK_EXPORT SarRadiometricCalibrationFunction
    : public itk::ImageFunction<TInputImage, typename itk::NumericTraits<typename TInputImage::PixelType>::AbsType, TCoordRep>
{
public:
  /** Standard class typedefs. */
  typedef SarRadiometricCalibrationFunction Self;
  typedef itk::ImageFunction<TInputImage, typename itk::NumericTraits<typename TInputImage::PixelType>::AbsType, TCoordRep> Superclass;
  typedef itk::SmartPointer<Self>       Pointer;
  typedef itk::SmartPointer<const Self> ConstPointer;

  /** Run-time type information (and related methods). */
  itkTypeMacro(SarRadiometricCalibrationFunction, itk::ImageFunction);

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** InputImageType typedef support. */
  typedef TInputImage                              InputImageType;
  typedef typename InputImageType::PixelType       InputPixelType;
  typedef typename Superclass::OutputType          OutputType;
  typedef typename Superclass::IndexType           IndexType;
  typedef typename Superclass::ContinuousIndexType ContinuousIndexType;
  typedef typename Superclass::PointType           PointType;

  itkStaticConstMacro(ImageDimension, unsigned int, InputImageType::ImageDimension);

  /** Datatype used for the evaluation */
  typedef double RealType;
  //  typedef otb::Functor::SarRadiometricCalibrationFunctor<RealType, RealType>           FunctorType;
  //  typedef typename FunctorType::RealType                        FunctorRealType;

  typedef otb::SarParametricMapFunction<InputImageType> ParametricFunctionType;
  typedef typename ParametricFunctionType::Pointer      ParametricFunctionPointer;
  typedef typename ParametricFunctionType::ConstPointer ParametricFunctionConstPointer;
  
  using S1ThermalNoiseLookupType = otb::S1ThermalNoiseLookupData<double>;
  using S1ThermalNoiseLookupPointerType = typename S1ThermalNoiseLookupType::Pointer;

  /** Evalulate the function at specified index */
  OutputType EvaluateAtIndex(const IndexType& index) const override;

  /** Evaluate the function at non-integer positions */
  OutputType Evaluate(const PointType& point) const override
  {
    IndexType index;
    this->ConvertPointToNearestIndex(point, index);
    return this->EvaluateAtIndex(index);
  }

  OutputType EvaluateAtContinuousIndex(const ContinuousIndexType& cindex) const override
  {
    IndexType index;
    this->ConvertContinuousIndexToNearestIndex(cindex, index);
    return this->EvaluateAtIndex(index);
  }

  /** Set the input image.
   * \warning this method caches BufferedRegion information.
   * If the BufferedRegion has changed, user must call
   * SetInputImage again to update cached values. */
  void SetInputImage(const InputImageType* ptr) override;


  /** Get/Set the Scale value */
  itkSetMacro(Scale, RealType);
  itkGetMacro(Scale, RealType);

  /** Get/Set the Noise value */
  itkSetObjectMacro(Noise, ParametricFunctionType);
  itkGetConstObjectMacro(Noise, ParametricFunctionType);
  itkGetObjectMacro(Noise, ParametricFunctionType);

  /** Get/Set the flag which indicate if we use the Offset value */
  itkSetMacro(EnableNoise, bool);
  itkGetMacro(EnableNoise, bool);

  /** Get/Set the AntennaPatternNewGain value */
  itkSetObjectMacro(AntennaPatternNewGain, ParametricFunctionType);
  itkGetConstObjectMacro(AntennaPatternNewGain, ParametricFunctionType);
  itkGetObjectMacro(AntennaPatternNewGain, ParametricFunctionType);

  /** Get/Set the AntennaPatternOldGain value */
  itkSetObjectMacro(AntennaPatternOldGain, ParametricFunctionType);
  itkGetObjectMacro(AntennaPatternOldGain, ParametricFunctionType);
  itkGetConstObjectMacro(AntennaPatternOldGain, ParametricFunctionType);

  /** Get/Set the IncidenceAngle value */
  itkSetObjectMacro(IncidenceAngle, ParametricFunctionType);
  itkGetConstObjectMacro(IncidenceAngle, ParametricFunctionType);
  itkGetObjectMacro(IncidenceAngle, ParametricFunctionType);

  /** Get/Set the RangeSpreadLoss value */
  itkSetObjectMacro(RangeSpreadLoss, ParametricFunctionType);
  itkGetConstObjectMacro(RangeSpreadLoss, ParametricFunctionType);
  itkGetObjectMacro(RangeSpreadLoss, ParametricFunctionType);

  /** Set the RescalingFactor value */
  itkSetMacro(RescalingFactor, RealType);

  /** Get/Set flag to indicate if these are used */
  itkSetMacro(ApplyAntennaPatternGain, bool);
  itkGetMacro(ApplyAntennaPatternGain, bool);

  itkSetMacro(ApplyIncidenceAngleCorrection, bool);
  itkGetMacro(ApplyIncidenceAngleCorrection, bool);

  itkSetMacro(ApplyRangeSpreadLossCorrection, bool);
  itkGetMacro(ApplyRangeSpreadLossCorrection, bool);

  itkSetMacro(ApplyLookupDataCorrection, bool);
  itkGetMacro(ApplyLookupDataCorrection, bool);

  itkSetMacro(ApplyRescalingFactor, bool);
  itkGetMacro(ApplyRescalingFactor, bool);

  typedef SarCalibrationLookupData::Pointer LookupDataPointer;

  /** Set SetCalibrationLookupData instance */
  void SetCalibrationLookupData(LookupDataPointer lut)
  {
    m_Lut = lut;
  }

protected:
  /** ctor */
  SarRadiometricCalibrationFunction();

  /** default, empty, virtual dtor */
  ~SarRadiometricCalibrationFunction() override
  {
  }

  /** print method */
  void PrintSelf(std::ostream& os, itk::Indent indent) const override;

  /** Flags to indicate if these values needs to be applied in calibration*/

private:
  SarRadiometricCalibrationFunction(const Self&) = delete;
  void operator=(const Self&) = delete;

  RealType                  m_Scale;
  bool                      m_EnableNoise;
  RealType                  m_RescalingFactor;
  bool                      m_ApplyAntennaPatternGain;
  bool                      m_ApplyIncidenceAngleCorrection;
  bool                      m_ApplyRangeSpreadLossCorrection;
  bool                      m_ApplyLookupDataCorrection;
  bool                      m_ApplyRescalingFactor;
  ParametricFunctionPointer m_Noise;
  ParametricFunctionPointer m_AntennaPatternNewGain;
  ParametricFunctionPointer m_AntennaPatternOldGain;
  ParametricFunctionPointer m_IncidenceAngle;
  ParametricFunctionPointer m_RangeSpreadLoss;
  LookupDataPointer         m_Lut;
  bool                      m_RemoveS1ThermalNoise;
  S1ThermalNoiseLookupPointerType m_S1ThermaNoise;
};

} // end namespace otb

#ifndef OTB_MANUAL_INSTANTIATION
#include "otbSarRadiometricCalibrationFunction.hxx"
#endif

#endif
