/* -*-c++-*- */
/* osgEarth - Dynamic map generation toolkit for OpenSceneGraph
 * Copyright 2008-2013 Pelican Mapping
 * http://osgearth.org
 *
 * osgEarth is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

#ifndef OSGEARTH_MODEL_SOURCE_H
#define OSGEARTH_MODEL_SOURCE_H 1

#include <osgEarth/Common>
#include <osgEarth/Config>
#include <osgEarth/NodeUtils>
#include <osgEarth/Progress>
#include <osgEarth/Revisioning>
#include <osgEarth/ThreadingUtils>
#include <osg/Referenced>

namespace osgEarth
{   
    class Map;
    
    /**
     * 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; }

        /** 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<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() { }

        osg::Node* createNode(
            const Map*            map,
            const osgDB::Options* dbOptions,
            ProgressCallback*     progress );

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

        /**
         * Add a post processing opeation - this will be called on any node
         * that enters the scene graph by the model source.
         */
        void addPostProcessor( NodeOperation* cb );
        
        /**
         * Remove a post processing operation
         */
        void removePostProcessor( NodeOperation* cb );

        /**
         * The vector of post processor callback operations
         */
        const NodeOperationVector& postProcessors() const { return _postProcessors; }


    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:

        /** Perform any one-time initialization */
        virtual void initialize( const osgDB::Options* dbOptions ) { }

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

    protected:
        /**
         * Fire the callbacks. The implementation class should call this whenever it adds
         * a new node.
         */
        void firePostProcessors( osg::Node* node );

    private:
        const ModelSourceOptions _options;
        optional<double> _minRange;
        optional<double> _maxRange;
        optional<int>    _renderOrder;

        NodeOperationVector       _postProcessors;
        mutable Threading::Mutex  _postProcessorsMutex;

        friend class Map;
        friend class MapEngine;
        friend class ModelSourceFactory;
    };

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

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

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

    /**
     * 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 );
    };
}

#endif // OSGEARTH_MODEL_SOURCE_H
