#ifndef __CPEXTENSIONS__INTERACTION__BASEINTERACTORSTYLE__H__
#define __CPEXTENSIONS__INTERACTION__BASEINTERACTORSTYLE__H__

#include <cpExtensions/cpExtensions_Export.h>

#include <chrono>
#include <map>
#include <utility>

#include <vtkInteractorStyle.h>

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

// -------------------------------------------------------------------------
#define cpExtensions_BaseInteractorStyle_Commands( C )                  \
  protected:                                                            \
  std::map< T##C##Command, void* > m_##C##Commands;                     \
public:                                                                 \
  inline void Add##C##Command( T##C##Command c, void* d )               \
  {                                                                     \
    if( c != NULL )                                                     \
    {                                                                   \
      this->m_##C##Commands[ c ] = d;                                   \
      this->Modified( );                                                \
    }                                                                   \
  }                                                                     \
  inline void Remove##C##Command( T##C##Command c )                     \
  {                                                                     \
    std::map< T##C##Command, void* >::iterator i =                      \
      this->m_##C##Commands.find( c );                                  \
    if( i != this->m_##C##Commands.end( ) )                             \
    {                                                                   \
      this->m_##C##Commands.erase( i );                                 \
      this->Modified( );                                                \
    }                                                                   \
  }

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

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

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

      // Callbacks types
      typedef void ( *TMouseCommand )(
        void*, const ButtonID&, int*, double*, bool, bool, bool
        );
      typedef void ( *TMouseWheelCommand )( void*, const int&, bool, bool, bool );
      typedef void ( *TKeyCommand )( void*, const char& );
      typedef void ( *TVoidCommand )( void* );
      typedef TMouseCommand TMouseMoveCommand;
      typedef TMouseCommand TMouseClickCommand;
      typedef TMouseCommand TMouseDoubleClickCommand;
      typedef TVoidCommand  TExposeCommand;
      typedef TVoidCommand  TConfigureCommand;
      typedef TVoidCommand  TEnterCommand;
      typedef TVoidCommand  TLeaveCommand;

      // Associate callbacks for each event
      cpExtensions_BaseInteractorStyle_Commands( MouseMove );
      cpExtensions_BaseInteractorStyle_Commands( MouseClick );
      cpExtensions_BaseInteractorStyle_Commands( MouseDoubleClick );
      cpExtensions_BaseInteractorStyle_Commands( MouseWheel );
      cpExtensions_BaseInteractorStyle_Commands( Key );
      cpExtensions_BaseInteractorStyle_Commands( Expose );
      cpExtensions_BaseInteractorStyle_Commands( Configure );
      cpExtensions_BaseInteractorStyle_Commands( Enter );
      cpExtensions_BaseInteractorStyle_Commands( Leave );

    public:
      vtkObject* GetAssociatedObject( );
      const vtkObject* GetAssociatedObject( ) const;
      void SetAssociatedObject( vtkObject* obj );

      static void SetSetDoubleClickDelay( long delay );
      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->m_ActiveButton );
      }

      virtual void OnLeftButtonDown( );
      virtual void OnLeftButtonUp( );
      virtual void OnMiddleButtonDown( );
      virtual void OnMiddleButtonUp( );
      virtual void OnRightButtonDown( );
      virtual void OnRightButtonUp( );

      virtual void OnLeftClick( );
      virtual void OnLeftDoubleClick( );
      virtual void OnMiddleClick( );
      virtual void OnMiddleDoubleClick( );
      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( );

      virtual void Dolly( );
      virtual void Pan( );

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

      virtual void _Dolly( double factor );

      // Extension interface
      virtual bool _PickPosition( int idx[ 2 ], double pos[ 3 ] ) = 0;

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

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

    protected:
      vtkObject* m_AssociatedObject;
      double m_MotionFactor;

      /**
       * Button events
       */
      struct _TMouseButtonEvent
      {
        static long MaxDoubleClick;
        long m_LastButtonUp;
        long m_LastButtonHeld;
        long m_LastButtonDown;

        inline _TMouseButtonEvent( )
          { this->Reset( ); }
        inline void Reset( )
          {
            this->m_LastButtonUp = 0;
            this->m_LastButtonHeld = 0;
            this->m_LastButtonDown = -1;
          }
        inline void Release( )
          {
            long c = BaseInteractorStyle_DIFF_TIME;
            this->m_LastButtonUp = c;
            this->m_LastButtonHeld = c - this->m_LastButtonDown;
            this->m_LastButtonDown = -1;
          }
        inline unsigned char Clicks( )
          {
            unsigned char n = 0;
            long c = BaseInteractorStyle_DIFF_TIME;
            if(
              this->m_LastButtonHeld < MaxDoubleClick &&
              ( c - this->m_LastButtonUp ) < MaxDoubleClick
              )
            {
              this->Reset( );
              n = 2;
            }
            else
              n = 1;
            if( this->m_LastButtonDown < 0 )
              this->m_LastButtonDown = c;
            return( n );
          }
      };
      _TMouseButtonEvent m_LeftButtonEvent;
      _TMouseButtonEvent m_MiddleButtonEvent;
      _TMouseButtonEvent m_RightButtonEvent;
      ButtonID           m_ActiveButton;
    };

  } // ecapseman

} // ecapseman

#endif // __CPEXTENSIONS__INTERACTION__BASEINTERACTORSTYLE__H__

// eof - $RCSfile$