/* osgEarth
 * Copyright 2025 Pelican Mapping
 * MIT License
 */

#ifndef OSGEARTH_MODEL_SOURCE_H
#define OSGEARTH_MODEL_SOURCE_H 1

#include <osgEarth/Common>
#include <osgEarth/Config>
#include <osgEarth/GeoData>
#include <osgEarth/NodeUtils>
#include <osgEarth/Revisioning>
#include <osgEarth/Threading>
#include <osgEarth/Status>
#include <osgEarth/SceneGraphCallback>
#include <osg/Referenced>

namespace osgEarth
{   
    class Map;
    class ProgressCallback;
    
    /**
     * Configuration options for a models source.
     */
    class OSGEARTH_EXPORT ModelSourceOptions : public DriverConfigOptions
    {
    public:
        ModelSourceOptions( const ConfigOptions& options =ConfigOptions() );

        /** dtor */
        virtual ~ModelSourceOptions();

    public: // properties

        /** minimum camera range at which the data is visible */
        optional<float>& minRange() { return _minRange; }
        const optional<float>& minRange() const { return _minRange; }

        /** maximum camera range at which the data is visible */
        optional<float>& maxRange() { return _maxRange; }
        const optional<float>& maxRange() const { return _maxRange; }

        /** render bin order */
        optional<int>& renderOrder() { return _renderOrder; }
        const optional<int>& renderOrder() const { return _renderOrder; }

        optional<std::string>& renderBin() { return _renderBin; }
        const optional<std::string>& renderBin() const { return _renderBin; }

        /** whether to read the depth buffer when rendering */
        optional<bool>& depthTestEnabled() { return _depthTestEnabled; }
        const optional<bool>& depthTestEnabled() const { return _depthTestEnabled; }

    public:
        virtual Config getConfig() const;

    protected:
        virtual void mergeConfig( const Config& conf );
        
    private:
        void fromConfig( const Config& conf );

        optional<float> _minRange, _maxRange;
        optional<int> _renderOrder;
        optional<std::string> _renderBin;
        optional<bool> _depthTestEnabled;
        optional<bool> _overlay;
    };


    /**
     * A ModelSource is a plugin object that generates OSG nodes.
     */
    class OSGEARTH_EXPORT ModelSource : public osg::Object, public Revisioned
    {
    public:
        ModelSource( const ModelSourceOptions& options =ModelSourceOptions() );

        /** dtor */
        virtual ~ModelSource();

        /**
         * Opens the model source and returns a status. 
         */
        const Status& open(const osgDB::Options* readOptions);

        /**
         * Status after calling open.
         */
        const Status& getStatus() const { return _status; }

        /**
         * Creates the top level node for this model source.
         */
        osg::Node* createNode(
            const Map*        map,
            ProgressCallback* progress );

        /**
         * Access to the scene graph callbacks
         */
        void setSceneGraphCallbacks(SceneGraphCallbacks* value) { _sgCallbacks = value; }
        SceneGraphCallbacks* getSceneGraphCallbacks() const { return _sgCallbacks.get(); }


    public: // META_Object specialization
        // these are neseccary to we can load ModelSource implementations as plugins
        virtual osg::Object* cloneType() const { return 0; } // cloneType() not appropriate
        virtual osg::Object* clone(const osg::CopyOp&) const { return 0; } // clone() not appropriate
        virtual bool isSameKindAs(const osg::Object* obj) const { return dynamic_cast<const ModelSource*>(obj)!=NULL; }
        virtual const char* className() const { return "ModelSource"; }
        virtual const char* libraryName() const { return "osgEarth"; }

    public:

        /** Get the options used to create this model source */
        const ModelSourceOptions& getOptions() const { return _options; }

        /**
         * Gets the list of areas with data for this ModelSource
         */
        const DataExtentList& getDataExtents() const { return _dataExtents; }
        DataExtentList& getDataExtents() { return _dataExtents; }

    protected:

        /**
         * Perform one-time initialization and return the initial status.
         * This is called internally by open().
         */
        virtual Status initialize(const osgDB::Options* readOptions) =0;

        /**
         * Subclass implements this method to create a scene graph within the
         * context of the provided Map.
         */
        virtual osg::Node* createNodeImplementation(
            const Map*        map,
            ProgressCallback* progress ) =0;

    protected:
        
        /** Subclass can set the status with this */
        void setStatus(const Status& value) { _status = value; }

    private:
        const ModelSourceOptions _options;
        optional<double> _minRange;
        optional<double> _maxRange;
        optional<int>    _renderOrder;
        DataExtentList   _dataExtents;
        Status _status;

        osg::ref_ptr<SceneGraphCallbacks> _sgCallbacks;        

        friend class Map;
        friend class ModelSourceFactory;

    };

    //--------------------------------------------------------------------

    class OSGEARTH_EXPORT ModelSourceDriver : public osgDB::ReaderWriter
    {
    protected:
        const ModelSourceOptions& getModelSourceOptions( const osgDB::ReaderWriter::Options* rwOpt ) const;

        virtual ~ModelSourceDriver();
    };

    //--------------------------------------------------------------------

    /**
     * Creates TileSource instances and chains them together to create
     * tile source "pipelines" for data access and processing.
     */
    class OSGEARTH_EXPORT ModelSourceFactory
    {   
    public:
        static ModelSource* create( const ModelSourceOptions& options );

        virtual ~ModelSourceFactory();
    };
}

#endif // OSGEARTH_MODEL_SOURCE_H
