#ifndef __CPEXTENSIONS__VISUALIZATION__BASEINTERACTORSTYLE__H__
#define __CPEXTENSIONS__VISUALIZATION__BASEINTERACTORSTYLE__H__

#include <cpExtensions/cpExtensions_Export.h>

#include <chrono>
#include <vtkInteractorStyle.h>

/*
 * Compile ITK and VTK with: cmake -DCMAKE_CXX_FLAGS="-std=c++11" /dir/to/source
 */

/* =========================================================================
 * Double click algorithm taken from:
 * http://www.autohotkey.com/board/topic/56493-easiest-way-to-detect-double-clicks/
 * =========================================================================
 */

// -------------------------------------------------------------------------
#define BaseInteractorStyle_DIFF_TIME                           \
  std::chrono::duration_cast< std::chrono::milliseconds >(      \
    std::chrono::system_clock::now( ).time_since_epoch( )       \
    ).count( )

namespace cpExtensions
{
  namespace Visualization
  {
    /**
     */
    class cpExtensions_EXPORT BaseInteractorStyle
      : public vtkInteractorStyle
    {
    public:
      typedef BaseInteractorStyle Self;
      vtkTypeMacro( BaseInteractorStyle, vtkInteractorStyle );

      enum ButtonID
      {
        ButtonID_None = 0,
        ButtonID_Left,
        ButtonID_Middle,
        ButtonID_Right
      };

    public:
      static Self* New( );

      void DelegateTDxEvent( unsigned long event, void* calldata );

      // Possible mouse motion events
      virtual void OnMouseMove( ) { }
      virtual void OnMouseWheelForward( ) { }
      virtual void OnMouseWheelBackward( ) { }

      // Possible mouse click-related events
      inline ButtonID GetButtonID( ) const
      { return( this->ActiveButton ); }
      virtual void OnLeftButtonDown( ) { }
      virtual void OnLeftButtonUp( ) { }
      virtual void OnLeftClick( ) { }
      virtual void OnLeftDoubleClick( ) { }
      virtual void OnMiddleButtonDown( ) { }
      virtual void OnMiddleButtonUp( ) { }
      virtual void OnMiddleClick( ) { }
      virtual void OnMiddleDoubleClick( ) { }
      virtual void OnRightButtonDown( ) { }
      virtual void OnRightButtonUp( ) { }
      virtual void OnRightClick( ) { }
      virtual void OnRightDoubleClick( ) { }

      // Keyboard-related events
      virtual void OnChar( ) { }
      virtual void OnKeyDown( ) { }
      virtual void OnKeyUp( ) { }
      virtual void OnKeyPress( ) { }
      virtual void OnKeyRelease( ) { }

      // Other events
      virtual void OnExpose( ) { }
      virtual void OnConfigure( ) { }
      virtual void OnEnter( ) { }
      virtual void OnLeave( ) { }

      // Unused methods
      inline void StartState( int newstate ) { }
      inline void StopState( ) { }
      inline void StartAnimate( ) { }
      inline void StopAnimate( ) { }
      inline void StartRotate( ) { }
      inline void EndRotate( ) { }
      inline void StartZoom( ) { }
      inline void EndZoom( ) { }
      inline void StartPan( ) { }
      inline void EndPan( ) { }
      inline void StartSpin( ) { }
      inline void EndSpin( ) { }
      inline void StartDolly( ) { }
      inline void EndDolly( ) { }
      inline void StartUniformScale( ) { }
      inline void EndUniformScale( ) { }
      inline void StartTimer( ) { }
      inline void EndTimer( ) { }
      inline void StartTwoPointer( ) { }
      inline void EndTwoPointer( ) { }
      inline void OnTimer( ) { }

    protected:
      BaseInteractorStyle( );
      virtual ~BaseInteractorStyle( );

      static void _ProcessEvents(
        vtkObject* object,
        unsigned long event,
        void* clientdata,
        void* calldata
        );

    private:
      // Purposely not implemented
      BaseInteractorStyle( const Self& );
      Self& operator=( const Self& );

    protected:

      /**
       * Button events
       */
      struct MouseButtonEvent
      {
        static const long MAX_DOUBLE_CLICK;
        long LastButtonUp;
        long LastButtonHeld;
        long LastButtonDown;

        inline MouseButtonEvent( )
          { this->Reset( ); }
        inline void Reset( )
          {
            this->LastButtonUp = 0;
            this->LastButtonHeld = 0;
            this->LastButtonDown = -1;
          }
        inline void Release( )
          {
            long c = BaseInteractorStyle_DIFF_TIME;
            this->LastButtonUp = c;
            this->LastButtonHeld = c - this->LastButtonDown;
            this->LastButtonDown = -1;
          }
        inline unsigned char Clicks( )
          {
            unsigned char n = 0;
            long c = BaseInteractorStyle_DIFF_TIME;
            if(
              this->LastButtonHeld < MAX_DOUBLE_CLICK &&
              ( c - this->LastButtonUp ) < MAX_DOUBLE_CLICK
              )
            {
              this->Reset( );
              n = 2;
            }
            else
              n = 1;
            if( this->LastButtonDown < 0 )
              this->LastButtonDown = c;
            return( n );
          }
      };
      MouseButtonEvent LeftButtonEvent;
      MouseButtonEvent MiddleButtonEvent;
      MouseButtonEvent RightButtonEvent;
      ButtonID ActiveButton;
    };

  } // ecapseman

} // ecapseman

#endif // __CPEXTENSIONS__VISUALIZATION__BASEINTERACTORSTYLE__H__

// eof - $RCSfile$