/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
 *
 * This library is open source and may be redistributed and/or modified under
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSGVIEWER_GRAPHICWINDOW
#define OSGVIEWER_GRAPHICWINDOW 1

#include <osg/GraphicsContext>
#include <osg/Notify>

#include <osgGA/EventQueue>
#include <osgGA/GUIActionAdapter>

#include <osgViewer/Export>

namespace osgViewer {

/** Base class for providing Windowing API agnostic access to creating and managing graphisc window and events.
  * Note, the GraphicsWindow is subclassed from osg::GraphicsContext, and to provide an implemention you'll need to implement its 
  * range of pure virtual functions, you'll find these all have naming convention methodNameImplemention(..).
  * GraphicsWindow adds the event queue ontop of the GraphicsContext, thereby adding a mechnism for adapting Windowing events
  * as well as basics graphics context work, you should wire up custom GraphicsWindowImplementation to push their events through
  * into the EventQueue. */
class OSGVIEWER_EXPORT GraphicsWindow : public osg::GraphicsContext, public osgGA::GUIActionAdapter
{
    public:
    
        GraphicsWindow() { _eventQueue = new osgGA::EventQueue; }


        void setEventQueue(osgGA::EventQueue* eventQueue) { _eventQueue = eventQueue; }
        osgGA::EventQueue* getEventQueue() { return _eventQueue.get(); }
        const osgGA::EventQueue* getEventQueue() const { return _eventQueue.get(); }

        virtual void checkEvents() {}

        /** Set Window decoration.*/
        virtual void setWindowDecoration(bool /*flag*/) {}

        /** Get focus.*/
        virtual void grabFocus() {}
        
        /** Get focus on if the pointer is in this window.*/
        virtual void grabFocusIfPointerInWindow() {}

        /** Switch on/off the cursor.*/
        virtual void useCursor(bool /*cursorOn*/) {}

    public:

        /** Return whether a valid and usable GraphicsContext has been created.*/
        virtual bool valid() const { osg::notify(osg::NOTICE)<<"GraphicsWindow::realizeImplementation() not implemented."<<std::endl; return false; }

        /** Realise the GraphicsContext implementation, 
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual bool realizeImplementation() { osg::notify(osg::NOTICE)<<"GraphicsWindow::realizeImplementation() not implemented."<<std::endl; return false; }

        /** Return true if the graphics context has been realised, and is ready to use, implementation.
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual bool isRealizedImplementation() const  { osg::notify(osg::NOTICE)<<"GraphicsWindow::isRealizedImplementation() not implemented."<<std::endl; return false; }

        /** Close the graphics context implementation.
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual void closeImplementation()  { osg::notify(osg::NOTICE)<<"GraphicsWindow::closeImplementation() not implemented."<<std::endl; }

        /** Make this graphics context current implementation.
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual bool makeCurrentImplementation()  { osg::notify(osg::NOTICE)<<"GraphicsWindow::makeCurrentImplementation() not implemented."<<std::endl; return false;}
        
        /** Make this graphics context current with specified read context implementation.
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual bool makeContextCurrentImplementation(GraphicsContext* /*readContext*/)  { osg::notify(osg::NOTICE)<<"GraphicsWindow::makeContextCurrentImplementation(..) not implemented."<<std::endl; return false;}

        /** Release the graphics context.*/
        virtual bool releaseContextImplementation() {  osg::notify(osg::NOTICE)<<"GraphicsWindow::releaseContextImplementation(..) not implemented."<<std::endl; return false; }

        /** Pure virtual, Bind the graphics context to associated texture implementation.
          * Pure virtual - must be implemented by concrate implementations of GraphicsContext. */
        virtual void bindPBufferToTextureImplementation(GLenum /*buffer*/)  { osg::notify(osg::NOTICE)<<"GraphicsWindow::bindPBufferToTextureImplementation(..) not implemented."<<std::endl; }

        /** Swap the front and back buffers implementation.
          * Pure virtual - must be implemented by Concrate implementations of GraphicsContext. */
        virtual void swapBuffersImplementation()  { osg::notify(osg::NOTICE)<<"GraphicsWindow:: swapBuffersImplementation() not implemented."<<std::endl; }

    public:

        // Override from GUIActionAdapter
        virtual void requestRedraw() {}

        // Override from GUIActionAdapter
        virtual void requestContinuousUpdate(bool /*needed*/=true) {}

        // Override from GUIActionAdapter
        virtual void requestWarpPointer(float /*x*/,float /*y*/) {}


    protected:
    
        osg::ref_ptr<osgGA::EventQueue> _eventQueue;
        
};


}

#endif