/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkImplicitPlaneWidget2.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkImplicitPlaneWidget2
 * @brief   3D widget for manipulating an infinite plane
 *
 * This 3D widget defines an infinite plane that can be interactively placed
 * in a scene. The widget is assumed to consist of four parts: 1) a plane
 * contained in a 2) bounding box, with a 3) plane normal, which is rooted
 * at a 4) point on the plane. (The representation paired with this widget
 * determines the actual geometry of the widget.)
 *
 * To use this widget, you generally pair it with a vtkImplicitPlaneRepresentation
 * (or a subclass). Variuos options are available for controlling how the
 * representation appears, and how the widget functions.
 *
 * @par Event Bindings:
 * By default, the widget responds to the following VTK events (i.e., it
 * watches the vtkRenderWindowInteractor for these events):
 * <pre>
 * If the mouse is over the plane normal:
 *   LeftButtonPressEvent - select normal
 *   LeftButtonReleaseEvent - release normal
 *   MouseMoveEvent - orient the normal vector
 * If the mouse is over the origin point (handle):
 *   LeftButtonPressEvent - select handle
 *   LeftButtonReleaseEvent - release handle (if selected)
 *   MouseMoveEvent - move the origin point (constrained to the plane)
 * If the mouse is over the plane:
 *   LeftButtonPressEvent - select plane
 *   LeftButtonReleaseEvent - release plane (if selected)
 *   MouseMoveEvent - move the plane
 * If the mouse is over the outline:
 *   LeftButtonPressEvent - select outline
 *   LeftButtonReleaseEvent - release outline (if selected)
 *   MouseMoveEvent - move the outline
 * If the keypress characters are used
 *   'Down/Left' Move plane down
 *   'Up/Right' Move plane up
 * In all the cases, independent of what is picked, the widget responds to the
 * following VTK events:
 *   MiddleButtonPressEvent - move the plane
 *   MiddleButtonReleaseEvent - release the plane
 *   RightButtonPressEvent - scale the widget's representation
 *   RightButtonReleaseEvent - stop scaling the widget
 *   MouseMoveEvent - scale (if right button) or move (if middle button) the widget
 * </pre>
 *
 * @par Event Bindings:
 * Note that the event bindings described above can be changed using this
 * class's vtkWidgetEventTranslator. This class translates VTK events
 * into the vtkImplicitPlaneWidget2's widget events:
 * <pre>
 *   vtkWidgetEvent::Select -- some part of the widget has been selected
 *   vtkWidgetEvent::EndSelect -- the selection process has completed
 *   vtkWidgetEvent::Move -- a request for widget motion has been invoked
 *   vtkWidgetEvent::Up and vtkWidgetEvent::Down -- MovePlaneAction
 * </pre>
 *
 * @par Event Bindings:
 * In turn, when these widget events are processed, the vtkImplicitPlaneWidget2
 * invokes the following VTK events on itself (which observers can listen for):
 * <pre>
 *   vtkCommand::StartInteractionEvent (on vtkWidgetEvent::Select)
 *   vtkCommand::EndInteractionEvent (on vtkWidgetEvent::EndSelect)
 *   vtkCommand::InteractionEvent (on vtkWidgetEvent::Move)
 * </pre>
 *
 *
 * @par Event Bindings:
 * This class, and vtkImplicitPlaneRepresentation, are next generation VTK
 * widgets. An earlier version of this functionality was defined in the class
 * vtkImplicitPlaneWidget.
 *
 * @sa
 * vtk3DWidget vtkBoxWidget vtkPlaneWidget vtkLineWidget vtkPointWidget
 * vtkSphereWidget vtkImagePlaneWidget vtkImplicitCylinderWidget
*/

#ifndef vtkImplicitPlaneWidget2_h
#define vtkImplicitPlaneWidget2_h

#include "vtkInteractionWidgetsModule.h" // For export macro
#include "vtkAbstractWidget.h"

class vtkImplicitPlaneRepresentation;
class vtkInteractionCallback;

class VTKINTERACTIONWIDGETS_EXPORT vtkImplicitPlaneWidget2 : public vtkAbstractWidget
{
  friend class vtkInteractionCallback;

public:
  /**
   * Instantiate the object.
   */
  static vtkImplicitPlaneWidget2 *New();

  //@{
  /**
   * Standard vtkObject methods
   */
  vtkTypeMacro(vtkImplicitPlaneWidget2,vtkAbstractWidget);
  void PrintSelf(ostream& os, vtkIndent indent) override;
  //@}

  /**
   * Specify an instance of vtkWidgetRepresentation used to represent this
   * widget in the scene. Note that the representation is a subclass of vtkProp
   * so it can be added to the renderer independent of the widget.
   */
  void SetRepresentation( vtkImplicitPlaneRepresentation *rep );

  // Descritpion:
  // Disable/Enable the widget if needed.
  // Unobserved the camera if the widget is disabled.
  void SetEnabled(int enabling) override;

  /**
   * Observe/Unobserve the camera if the widget is locked/unlocked to update the
   * vtkImplicitePlaneRepresentation's normal.
   */
  void SetLockNormalToCamera(int lock);

  /**
   * Return the representation as a vtkImplicitPlaneRepresentation.
   */
  vtkImplicitPlaneRepresentation *GetImplicitPlaneRepresentation()
    {return reinterpret_cast<vtkImplicitPlaneRepresentation*>(this->WidgetRep);}

  /**
   * Create the default widget representation if one is not set.
   */
  void CreateDefaultRepresentation() override;

protected:
  vtkImplicitPlaneWidget2();
  ~vtkImplicitPlaneWidget2() override;

  // Manage the state of the widget
  int WidgetState;
  enum _WidgetState {Start=0,Active};

  // These methods handle events
  static void SelectAction(vtkAbstractWidget*);
  static void TranslateAction(vtkAbstractWidget*);
  static void ScaleAction(vtkAbstractWidget*);
  static void EndSelectAction(vtkAbstractWidget*);
  static void MoveAction(vtkAbstractWidget*);
  static void MovePlaneAction(vtkAbstractWidget*);
  static void SelectAction3D(vtkAbstractWidget*);
  static void EndSelectAction3D(vtkAbstractWidget*);
  static void MoveAction3D(vtkAbstractWidget*);

  /**
   * Update the cursor shape based on the interaction state. Returns 1
   * if the cursor shape requested is different from the existing one.
   */
  int UpdateCursorShape( int interactionState );

  //@{
  /**
   * Handle the interaction callback that may come from the representation.
   */
  vtkInteractionCallback *InteractionCallback;
  void InvokeInteractionCallback();
  //@}

private:
  vtkImplicitPlaneWidget2(const vtkImplicitPlaneWidget2&) = delete;
  void operator=(const vtkImplicitPlaneWidget2&) = delete;
};

#endif
