/* -*-c++-*- */
/* osgEarth - Dynamic map generation toolkit for OpenSceneGraph
 * Copyright 2008-2010 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 OSGEARTHSYMBOLOGY_RESOURCE_LIBRARY_H
#define OSGEARTHSYMBOLOGY_RESOURCE_LIBRARY_H 1

#include <osgEarthSymbology/Common>
#include <osgEarthSymbology/Skins>
#include <osgEarth/ThreadingUtils>
#include <osgEarth/Random>
#include <map>

namespace osgEarth { namespace Symbology
{
    /** 
     * ResourceLibrary manages a collection of external resources that a
     * build system can use the construct geometries.
     *
     * TODO: This class PROBABLY NEEDS the ability to share a mutex with
     * whatever session is using it... like in osgGIS...
     */
    class OSGEARTHSYMBOLOGY_EXPORT ResourceLibrary : public osg::Referenced
    {
    public:
        /**
         * Attempts to create and load a resource library from an XML
         * resource catalog residing at the specified URL.
         */         
        static ResourceLibrary* create( const URI& uri );

    public:
        /**
         * Creates a new resource library
         */
        ResourceLibrary( const Config& conf =Config() );

        /**
         * Adds a resoure to the library.
         */
        void addResource( Resource* resource );

        /**
         * Removes a resource from the library.
         */
        void removeResource( Resource* resource );


    public: // Skin resource functions

        /**
         * Finds and returns a Skin resource by name.
         */
        SkinResource* getSkin( const std::string& name ) const;

        /**
         * Returns a list of all Skin resources.
         */
        void getSkins( SkinResourceVector& output ) const;

        /**
         * Returns a list of all Skin resources that match the criteria specified
         * in the symbol.
         */
        void getSkins( const SkinSymbol* symbol, SkinResourceVector& output ) const;

        /**
         * Returns a skin that matches the criteria specified in the symbol. The method
         * will randomly select a suitable skin if there are more than one match. If the
         * symbol contains a random seed, it will use that to seed the selection in order
         * to provide consistency.
         */
        SkinResource* getSkin( const SkinSymbol* symbol, Random& prng ) const;


    public: // Model resource functions

        //TODO

    public: // serialization functions

        void mergeConfig( const Config& conf );

    protected:
        typedef std::map< const Symbol*, Random > RandomMap;

        Threading::ReadWriteMutex _mutex;
        SkinResourceMap           _skins;

        bool matches( const SkinSymbol* symbol, SkinResource* skin ) const;
    };


    typedef std::map< std::string, osg::ref_ptr<ResourceLibrary> > ResourceLibraryMap;


} } // namespace osgEarth::Symbology

#endif // OSGEARTHSYMBOLOGY_RESOURCE_LIBRARY_H
