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

  Program:   Visualization Toolkit
  Module:    vtkBoxWidget.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   vtkBoxWidget
 * @brief   orthogonal hexahedron 3D widget
 *
 * This 3D widget defines a region of interest that is represented by an
 * arbitrarily oriented hexahedron with interior face angles of 90 degrees
 * (orthogonal faces). The object creates 7 handles that can be moused on and
 * manipulated. The first six correspond to the six faces, the seventh is in
 * the center of the hexahedron. In addition, a bounding box outline is shown,
 * the "faces" of which can be selected for object rotation or scaling. A
 * nice feature of the object is that the vtkBoxWidget, like any 3D widget,
 * will work with the current interactor style. That is, if vtkBoxWidget does
 * not handle an event, then all other registered observers (including the
 * interactor style) have an opportunity to process the event. Otherwise, the
 * vtkBoxWidget will terminate the processing of the event that it handles.
 *
 * To use this object, just invoke SetInteractor() with the argument of the
 * method a vtkRenderWindowInteractor.  You may also wish to invoke
 * "PlaceWidget()" to initially position the widget. The interactor will act
 * normally until the "i" key (for "interactor") is pressed, at which point the
 * vtkBoxWidget will appear. (See superclass documentation for information
 * about changing this behavior.) By grabbing the six face handles (use the
 * left mouse button), faces can be moved. By grabbing the center handle
 * (with the left mouse button), the entire hexahedron can be
 * translated. (Translation can also be employed by using the
 * "shift-left-mouse-button" combination inside of the widget.) Scaling is
 * achieved by using the right mouse button "up" the render window (makes the
 * widget bigger) or "down" the render window (makes the widget smaller). To
 * rotate vtkBoxWidget, pick a face (but not a face handle) and move the left
 * mouse. (Note: the mouse button must be held down during manipulation.)
 * Events that occur outside of the widget (i.e., no part of the widget is
 * picked) are propagated to any other registered obsevers (such as the
 * interaction style).  Turn off the widget by pressing the "i" key again.
 * (See the superclass documentation on key press activiation.)
 *
 * The vtkBoxWidget is very flexible. It can be used to select, cut, clip, or
 * perform any other operation that depends on an implicit function (use the
 * GetPlanes() method); or it can be used to transform objects using a linear
 * transformation (use the GetTransform() method). Typical usage of the
 * widget is to make use of the StartInteractionEvent, InteractionEvent, and
 * EndInteractionEvent events. The InteractionEvent is called on mouse
 * motion; the other two events are called on button down and button up
 * (either left or right button).
 *
 * Some additional features of this class include the ability to control the
 * rendered properties of the widget. You can set the properties of the
 * selected and unselected representations of the parts of the widget. For
 * example, you can set the property for the handles, faces, and outline in
 * their normal and selected states.
 *
 * The box widget can be oriented by specifying a transformation matrix.
 * This transformation is applied to the initial bounding box as defined by
 * the PlaceWidget() method. DO NOT ASSUME that the transformation is applied
 * to a unit box centered at the origin; this is wrong!
 *
 * @sa
 * vtk3DWidget vtkPointWidget vtkLineWidget vtkPlaneWidget
 * vtkImplicitPlaneWidget vtkImagePlaneWidget
*/

#ifndef vtkBoxWidget_h
#define vtkBoxWidget_h

#include "vtkInteractionWidgetsModule.h" // For export macro
#include "vtk3DWidget.h"

class vtkActor;
class vtkCellPicker;
class vtkPlanes;
class vtkPoints;
class vtkPolyData;
class vtkPolyDataMapper;
class vtkProp;
class vtkProperty;
class vtkSphereSource;
class vtkTransform;

class VTKINTERACTIONWIDGETS_EXPORT vtkBoxWidget : public vtk3DWidget
{
public:
  /**
   * Instantiate the object.
   */
  static vtkBoxWidget *New();

  vtkTypeMacro(vtkBoxWidget,vtk3DWidget);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  //@{
  /**
   * Methods that satisfy the superclass' API.
   */
  void SetEnabled(int) override;
  void PlaceWidget(double bounds[6]) override;
  void PlaceWidget() override
    {this->Superclass::PlaceWidget();}
  void PlaceWidget(double xmin, double xmax, double ymin, double ymax,
                   double zmin, double zmax) override
    {this->Superclass::PlaceWidget(xmin,xmax,ymin,ymax,zmin,zmax);}
  //@}

  /**
   * Get the planes describing the implicit function defined by the box
   * widget. The user must provide the instance of the class vtkPlanes. Note
   * that vtkPlanes is a subclass of vtkImplicitFunction, meaning that it can
   * be used by a variety of filters to perform clipping, cutting, and
   * selection of data.  (The direction of the normals of the planes can be
   * reversed enabling the InsideOut flag.)
   */
  void GetPlanes(vtkPlanes *planes);

  //@{
  /**
   * Set/Get the InsideOut flag. When off, the normals point out of the
   * box. When on, the normals point into the hexahedron.  InsideOut
   * is off by default.
   */
  vtkSetMacro(InsideOut,int);
  vtkGetMacro(InsideOut,int);
  vtkBooleanMacro(InsideOut,int);
  //@}

  /**
   * Retrieve a linear transform characterizing the transformation of the
   * box. Note that the transformation is relative to where PlaceWidget
   * was initially called. This method modifies the transform provided. The
   * transform can be used to control the position of vtkProp3D's, as well as
   * other transformation operations (e.g., vtkTranformPolyData).
   */
  virtual void GetTransform(vtkTransform *t);

  /**
   * Set the position, scale and orientation of the box widget using the
   * transform specified. Note that the transformation is relative to
   * where PlaceWidget was initially called (i.e., the original bounding
   * box).
   */
  virtual void SetTransform(vtkTransform* t);

  /**
   * Grab the polydata (including points) that define the box widget. The
   * polydata consists of 6 quadrilateral faces and 15 points. The first
   * eight points define the eight corner vertices; the next six define the
   * -x,+x, -y,+y, -z,+z face points; and the final point (the 15th out of 15
   * points) defines the center of the hexahedron. These point values are
   * guaranteed to be up-to-date when either the InteractionEvent or
   * EndInteractionEvent events are invoked. The user provides the
   * vtkPolyData and the points and cells are added to it.
   */
  void GetPolyData(vtkPolyData *pd);

  //@{
  /**
   * Get the handle properties (the little balls are the handles). The
   * properties of the handles when selected and normal can be
   * set.
   */
  vtkGetObjectMacro(HandleProperty,vtkProperty);
  vtkGetObjectMacro(SelectedHandleProperty,vtkProperty);
  //@}

  //@{
  /**
   * Switches handles (the spheres) on or off by manipulating the actor
   * visibility.
   */
  void HandlesOn();
  void HandlesOff();
  //@}

  //@{
  /**
   * Get the face properties (the faces of the box). The
   * properties of the face when selected and normal can be
   * set.
   */
  vtkGetObjectMacro(FaceProperty,vtkProperty);
  vtkGetObjectMacro(SelectedFaceProperty,vtkProperty);
  //@}

  //@{
  /**
   * Get the outline properties (the outline of the box). The
   * properties of the outline when selected and normal can be
   * set.
   */
  vtkGetObjectMacro(OutlineProperty,vtkProperty);
  vtkGetObjectMacro(SelectedOutlineProperty,vtkProperty);
  //@}

  //@{
  /**
   * Control the representation of the outline. This flag enables
   * face wires. By default face wires are off.
   */
  void SetOutlineFaceWires(int);
  vtkGetMacro(OutlineFaceWires,int);
  void OutlineFaceWiresOn() {this->SetOutlineFaceWires(1);}
  void OutlineFaceWiresOff() {this->SetOutlineFaceWires(0);}
  //@}

  //@{
  /**
   * Control the representation of the outline. This flag enables
   * the cursor lines running between the handles. By default cursor
   * wires are on.
   */
  void SetOutlineCursorWires(int);
  vtkGetMacro(OutlineCursorWires,int);
  void OutlineCursorWiresOn() {this->SetOutlineCursorWires(1);}
  void OutlineCursorWiresOff() {this->SetOutlineCursorWires(0);}
  //@}

  //@{
  /**
   * Control the behavior of the widget. Translation, rotation, and
   * scaling can all be enabled and disabled.
   */
  vtkSetMacro(TranslationEnabled,int);
  vtkGetMacro(TranslationEnabled,int);
  vtkBooleanMacro(TranslationEnabled,int);
  vtkSetMacro(ScalingEnabled,int);
  vtkGetMacro(ScalingEnabled,int);
  vtkBooleanMacro(ScalingEnabled,int);
  vtkSetMacro(RotationEnabled,int);
  vtkGetMacro(RotationEnabled,int);
  vtkBooleanMacro(RotationEnabled,int);
  //@}

protected:
  vtkBoxWidget();
  ~vtkBoxWidget() override;

  // Manage the state of the widget
  int State;
  enum WidgetState
  {
    Start=0,
    Moving,
    Scaling,
    Outside
  };

  // Handles the events
  static void ProcessEvents(vtkObject* object,
                            unsigned long event,
                            void* clientdata,
                            void* calldata);

  // ProcessEvents() dispatches to these methods.
  virtual void OnMouseMove();
  virtual void OnLeftButtonDown();
  virtual void OnLeftButtonUp();
  virtual void OnMiddleButtonDown();
  virtual void OnMiddleButtonUp();
  virtual void OnRightButtonDown();
  virtual void OnRightButtonUp();

  // the hexahedron (6 faces)
  vtkActor          *HexActor;
  vtkPolyDataMapper *HexMapper;
  vtkPolyData       *HexPolyData;
  vtkPoints         *Points;  //used by others as well
  double             N[6][3]; //the normals of the faces

  // A face of the hexahedron
  vtkActor          *HexFace;
  vtkPolyDataMapper *HexFaceMapper;
  vtkPolyData       *HexFacePolyData;

  // glyphs representing hot spots (e.g., handles)
  vtkActor          **Handle;
  vtkPolyDataMapper **HandleMapper;
  vtkSphereSource   **HandleGeometry;
  virtual void PositionHandles();
  int HighlightHandle(vtkProp *prop); //returns cell id
  void HighlightFace(int cellId);
  void HighlightOutline(int highlight);
  void ComputeNormals();
  void SizeHandles() override;

  // wireframe outline
  vtkActor          *HexOutline;
  vtkPolyDataMapper *OutlineMapper;
  vtkPolyData       *OutlinePolyData;

  // Do the picking
  vtkCellPicker *HandlePicker;
  vtkCellPicker *HexPicker;
  vtkActor *CurrentHandle;
  int      CurrentHexFace;

  // Register internal Pickers within PickingManager
  void RegisterPickers() override;

  // Methods to manipulate the hexahedron.
  virtual void Translate(double *p1, double *p2);
  virtual void Scale(double *p1, double *p2, int X, int Y);
  virtual void Rotate(int X, int Y, double *p1, double *p2, double *vpn);
  void MovePlusXFace(double *p1, double *p2);
  void MoveMinusXFace(double *p1, double *p2);
  void MovePlusYFace(double *p1, double *p2);
  void MoveMinusYFace(double *p1, double *p2);
  void MovePlusZFace(double *p1, double *p2);
  void MoveMinusZFace(double *p1, double *p2);

  //"dir" is the direction in which the face can be moved i.e. the axis passing
  //through the center
  void MoveFace(double *p1, double *p2, double *dir,
                double *x1, double *x2, double *x3, double *x4,
                double *x5);
  //Helper method to obtain the direction in which the face is to be moved.
  //Handles special cases where some of the scale factors are 0.
  void GetDirection(const double Nx[3],const double Ny[3],
                    const double Nz[3], double dir[3]);

  // Transform the hexahedral points (used for rotations)
  vtkTransform *Transform;

  // Properties used to control the appearance of selected objects and
  // the manipulator in general.
  vtkProperty *HandleProperty;
  vtkProperty *SelectedHandleProperty;
  vtkProperty *FaceProperty;
  vtkProperty *SelectedFaceProperty;
  vtkProperty *OutlineProperty;
  vtkProperty *SelectedOutlineProperty;
  void CreateDefaultProperties();

  // Control the orientation of the normals
  int InsideOut;
  int OutlineFaceWires;
  int OutlineCursorWires;
  void GenerateOutline();

  // Control whether scaling, rotation, and translation are supported
  int TranslationEnabled;
  int ScalingEnabled;
  int RotationEnabled;

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

#endif
