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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkBorderWidget.h,v $

  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.

=========================================================================*/
// .NAME vtkBorderWidget - place a border around a 2D rectangular region
// .SECTION Description
// This class is a superclass for 2D widgets that may require a rectangular
// border. Besides drawing a border, the widget provides methods for resizing
// and moving the rectangular region (and associated border). The widget
// provides methods and internal data members so that subclasses can take
// advantage of this widgets capabilities, requiring only that the subclass
// defines a "representation", i.e., some combination of props or actors
// that can be managed in the 2D rectangular region. 
//
// The class defines basic positioning functionality, including the ability
// to size the widget with locked x/y proportions. The area within the border
// may be made "selectable" as well, meaning that a selection event interior
// to the widget invokes a virtual SelectRegion() method, which can be used
// to pick objects or otherwise manipulate data interior to the widget.
//
// .SECTION Event Bindings
// By default, the widget responds to the following VTK events (i.e., it
// watches the vtkRenderWindowInteractor for these events):
// <pre>
// On the boundary of the widget:
//   LeftButtonPressEvent - select boundary
//   LeftButtonReleaseEvent - deselect boundary
//   MouseMoveEvent - move/resize widget depending on which portion of the
//                    boundary was selected.
// On the interior of the widget:
//   LeftButtonPressEvent - invoke SelectButton() callback (if the ivar
//                          Selectable is on)
// Anywhere on the widget:
//   MiddleButtonPressEvent - move the widget
// </pre>
//
// Note that the event bindings described above can be changed using this
// class's vtkWidgetEventTranslator. This class translates VTK events 
// into the vtkBorderWidget's widget events:
// <pre>
//   vtkWidgetEvent::Select -- some part of the widget has been selected
//   vtkWidgetEvent::EndSelect -- the selection process has completed
//   vtkWidgetEvent::Translate -- the widget is to be translated
//   vtkWidgetEvent::Move -- a request for slider motion has been invoked
// </pre>
//
// In turn, when these widget events are processed, this widget 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>

// .SECTION See Also
// vtkInteractorObserver vtkCameraInterpolator


#ifndef __vtkBorderWidget_h
#define __vtkBorderWidget_h

#include "vtkAbstractWidget.h"

class vtkBorderRepresentation;


class VTK_WIDGETS_EXPORT vtkBorderWidget : public vtkAbstractWidget
{
public:
  // Description:
  // Method to instantiate class.
  static vtkBorderWidget *New();

  // Description;
  // Standard methods for class.
  vtkTypeRevisionMacro(vtkBorderWidget,vtkAbstractWidget);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Indicate whether the interior region of the widget can be selected or
  // not. If not, then events (such as left mouse down) allow the user to
  // "move" the widget, and no selection is possible. Otherwise the
  // SelectRegion() method is invoked.
  vtkSetMacro(Selectable,int);
  vtkGetMacro(Selectable,int);
  vtkBooleanMacro(Selectable,int);


  // Description:
  // Indicate whether the boundary of the widget can be resized.
  // If not, the cursor will not change to "resize" type when mouse
  // over the boundary.
  vtkSetMacro(Resizable,int);
  vtkGetMacro(Resizable,int);
  vtkBooleanMacro(Resizable,int);


  // Description:
  // 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(vtkBorderRepresentation *r)
    {this->Superclass::SetWidgetRepresentation(reinterpret_cast<vtkWidgetRepresentation*>(r));}
  
  // Description:
  // Create the default widget representation if one is not set. 
  virtual void CreateDefaultRepresentation();

protected:
  vtkBorderWidget();
  ~vtkBorderWidget();

  // Description:
  // Subclasses generally implement this method. The SelectRegion() method
  // offers a subclass the chance to do something special if the interior
  // of the widget is selected.
  virtual void SelectRegion(double eventPos[2]);

  //enable the selection of the region interior to the widget
  int Selectable;
  int Resizable;

  //processes the registered events
  static void SelectAction(vtkAbstractWidget*);
  static void TranslateAction(vtkAbstractWidget*);
  static void EndSelectAction(vtkAbstractWidget*);
  static void MoveAction(vtkAbstractWidget*);

  // Special internal methods to support subclasses handling events.
  // If a non-zero value is returned, the subclass is handling the event.
  virtual int SubclassSelectAction() {return 0;}
  virtual int SubclassTranslateAction() {return 0;}
  virtual int SubclassEndSelectAction() {return 0;}
  virtual int SubclassMoveAction() {return 0;}
  
  // helper methods for cursoe management
  virtual void SetCursor(int State);

//BTX
  //widget state
  int WidgetState;
  enum _WidgetState{Start=0,Define,Manipulate,Selected};
//ETX

private:
  vtkBorderWidget(const vtkBorderWidget&);  //Not implemented
  void operator=(const vtkBorderWidget&);  //Not implemented
};

#endif
