//==============================================================================
// Copyright 2019-2020 Kitware, Inc., Kitware SAS
// Authors: Laurenson Nick (Kitware SAS)
// Creation date: 2019-02-08
//
// 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 VTK_SLAM_MANAGER_H
#define VTK_SLAM_MANAGER_H

#include "vtkSlam.h"
#include <vtkSetGet.h>

// This custom macro is needed to make the SlamManager time agnostic
// The SlamManager needs to know when RequestData is called and if it's due
// to a new timestep being requested or due to Slam parameters being changed.
// By keeping track of the last time the parameters were modified there is
// no ambiguty anymore. This mecanimsm is similar to the one used by the ParaView filter
// PlotDataOverTime
#undef vtkCustomSetMacro
#define vtkCustomSetMacro(name, type)                                                            \
virtual void Set##name(type _arg)                                                                \
{                                                                                                \
  vtkDebugMacro(<< this->GetClassName() << " (" << this << "): setting " #name " to " << _arg);  \
  if (this->name != _arg)                                                                        \
  {                                                                                              \
    this->name = _arg;                                                                           \
    this->ParametersModificationTime.Modified();                                                 \
  }                                                                                              \
}

class VTK_EXPORT vtkSlamManager : public vtkSlam
{
public:
  static vtkSlamManager* New();
  vtkTypeMacro(vtkSlamManager, vtkSlam)
  void PrintSelf(ostream& os, vtkIndent indent) override;

  //! @{ @copydoc FirstFrame
  vtkGetMacro(FirstFrame, int)
  vtkCustomSetMacro(FirstFrame, int)
  //! @}

  //! @{ @copydoc LastFrame
  vtkGetMacro(LastFrame, int)
  vtkCustomSetMacro(LastFrame, int)
  //! @}

  //! @{ @copydoc StepSize
  vtkGetMacro(StepSize, int)
  vtkCustomSetMacro(StepSize, int)
  //! @}

  //! @{ @copydoc AllFrames
  vtkGetMacro(AllFrames, bool)
  vtkCustomSetMacro(AllFrames, bool)
  //! @}

protected:
  vtkSlamManager();
  int RequestUpdateExtent(vtkInformation*,
                          vtkInformationVector**,
                          vtkInformationVector*) override;
  int RequestData(vtkInformation* request,
                  vtkInformationVector** inputVector,
                  vtkInformationVector* outputVector) override;

  //! Overwrite FirstFrame and LastFrame to process all the frame
  bool AllFrames = true;

  //! First frame to be process
  int FirstFrame = 0;

  //! No frame after this frame will be processed. In case StepSize is not 1 it corresponds to
  //! the last frame processed
  int LastFrame = 0;

  //! Process one frame every StepSize frames (ex: every frame, every 2 frames, 3 frames, ...)
  int StepSize = 1;

private:
  vtkSlamManager(const vtkSlamManager&) = delete;
  void operator=(const vtkSlamManager&) = delete;

  bool FirstIteration = true;
  int CurrentFrame = 0;
  unsigned long LastModifyTime = 0;
  std::vector<vtkSmartPointer<vtkPolyData>> Cache;
};

#endif // VTK_SLAM_MANAGER_H