#ifndef OSGUTIL_SCENEVIEW
#define OSGUTIL_SCENEVIEW 1

#include <osg/Node>
#include <osg/GeoState>
#include <osg/Light>
#include <osg/Camera>

#include <osgUtil/RenderVisitor>

#include <osgUtil/Export>

namespace osgUtil {

/**
 * SceneView is literaly a view of a scene, encapsulating the
 * camera, global state, lights and the scene itself.  Provides
 * methods for setting up the view and rendering it.
*/
class OSGUTIL_EXPORT SceneView : public osg::Referenced
{
    public:

        /** Constrcut a default scene view.*/
        SceneView();

        /** Set the data which to view. The data will typically be
         *  an osg::Scene but can be any osg::Node type.
         */
        void setSceneData(osg::Node* node) { _sceneData = node; _need_compile = true;}
        /** Get the scene data which to view. The data will typically be
         *  an osg::Scene but can be any osg::Node type.
         */
        osg::Node* getSceneData() { return _sceneData.get(); }

        /** Set the viewport of the scene view. */
        void setViewport(int x,int y,int width,int height)
        {
            _view[0] = x;
            _view[1] = y;
            _view[2] = width;
            _view[3] = height;
        }
        
        /** Get the viewport of the scene view. */
        void getViewport(int& x,int& y,int& width,int& height)
        {
            x = _view[0];
            y = _view[1];
            width = _view[2];
            height = _view[3];
        }

        /** Set scene view to use default global state, light, camera
         *  and render visitor.
        */
        void setDefaults();

        /** Set the background color used in glClearColor().
            Defaults to an off blue color.*/
        void setBackgroundColor(const osg::Vec4& color) { _backgroundColor=color; }
        /** Get the background color.*/
        const osg::Vec4& getBackgroundColor() const { return _backgroundColor; }

        void setGlobalState(osg::GeoState* state) { _globalState = state; }
        osg::GeoState* getGlobalState() const { return _globalState.get(); }

        enum LightingMode {
            HEADLIGHT, // default
            SKY_LIGHT,
            NO_SCENEVIEW_LIGHT
        };

        void setLightingMode(LightingMode mode) { _lightingMode=mode; }
        LightingMode getLightingMode() const { return _lightingMode; }

        void setLight(osg::Light* light) { _light = light; }
        osg::Light* getLight() const { return _light.get(); }
        
        void setCamera(osg::Camera* camera) { _camera = camera; }
        osg::Camera* getCamera() const { return _camera.get(); }
        
        void setRenderVisitor(osgUtil::RenderVisitor* rv) { _renderVisitor = rv; }
        osgUtil::RenderVisitor* getRenderVisitor() const { return _renderVisitor.get(); }

        void setLODBias(float bias) { _lodBias = bias; }
        float getLODBias() const { return _lodBias; }

        /** Set to true if you want SceneView to automatically calculate values
           for the near/far clipping planes, each frame, set false to use camera's
           internal near and far planes.  Default value is true.
        */
	void setCalcNearFar(bool calc) { _calc_nearfar = calc; }
        /** return true if SceneView automatically caclculates near and 
            far clipping planes for each frame.
        */
        bool getCalcNearFar() { return _calc_nearfar; }

        /** Calculate, via glUnProject, the object coordinates of a window point.
            Note, current implementation requires that SceneView::draw() has been previously called
            for projectWindowIntoObject to produce valid values.  Consistent with OpenGL
            windows coordinates are calculated relative to the bottom left of the window.
            Returns true on successful projection.
        */
        bool projectWindowIntoObject(const osg::Vec3& window,osg::Vec3& object) const;

        /** Calculate, via glUnProject, the object coordinates of a window x,y
            when projected onto the near and far planes.
            Note, current implementation requires that SceneView::draw() has been previously called
            for projectWindowIntoObject to produce valid values.  Consistent with OpenGL
            windows coordinates are calculated relative to the bottom left of the window.
            Returns true on successful projection.
        */
        bool projectWindowXYIntoObject(int x,int y,osg::Vec3& near_point,osg::Vec3& far_point) const;

        /** Calculate, via glProject, the object coordinates of a window.
            Note, current implementation requires that SceneView::draw() has been previously called
            for projectWindowIntoObject to produce valid values.  Consistent with OpenGL
            windows coordinates are calculated relative to the bottom left of the window,
            whereas as window API's normally have the top left as the origin,
            so you may need to pass in (mouseX,window_height-mouseY,...).
            Returns true on successful projection.
        */
        bool projectObjectIntoWindow(const osg::Vec3& object,osg::Vec3& window) const;


        virtual void cull();
        virtual void draw();
        
    protected:

        virtual ~SceneView();

        osg::ref_ptr<osg::Node>                     _sceneData;
        osg::ref_ptr<osg::GeoState>                 _globalState;
        osg::ref_ptr<osg::Light>                    _light;
        osg::ref_ptr<osg::Camera>                   _camera;
        osg::ref_ptr<osgUtil::RenderVisitor>        _renderVisitor;
        
        bool _need_compile;
        bool _calc_nearfar;

        osg::Vec4 _backgroundColor;

        double _near_plane;
        double _far_plane;
        
        float _lodBias;

        // viewport x,y,width,height respectiveyly.
        GLint _view[4];

        // model and project matices, used by glUnproject to get
        // to generate rays form the eyepoint through the mouse x,y.
        GLdouble _model[16];
        GLdouble _proj[16];

        LightingMode _lightingMode;

};

};

#endif