/* -*-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 OSGEARTHSYMBOLOGY_SYMBOL_H
#define OSGEARTHSYMBOLOGY_SYMBOL_H 1

#include <osgEarthSymbology/Common>
#include <osgEarth/Config>
#include <osgEarth/URI>
#include <osg/Referenced>
#include <vector>

#define META_Symbol(name) \
    virtual bool isSameKindAs(const Symbol* rhs) const { return dynamic_cast<const name *>(rhs)!=NULL; } \
    virtual const char* className() const { return #name; }


namespace osgEarth { namespace Symbology
{
    class Style;
    
    /**
     * Abstract base class for all Symbol types.
     */
    class OSGEARTHSYMBOLOGY_EXPORT Symbol : public osg::Referenced
    {
    public:
        const URIContext& uriContext() const { return _uriContext; }

        virtual Config getConfig() const { return Config(); }

    public: // META_Symbol methods
        virtual bool isSameKindAs(const Symbol* sym) const =0;
        virtual const char* className() const =0;        

    protected:
        URIContext _uriContext;

        static bool match(const std::string& key, const char* pattern);

        Symbol( const Config& conf =Config() );

        virtual ~Symbol() { }
    };
    typedef std::vector<osg::ref_ptr<Symbol> > SymbolList;

    /**
     * A Factory that can create a Symbol from a Config
     */
    class OSGEARTHSYMBOLOGY_EXPORT SymbolFactory : public osg::Referenced
    {
    public:
        virtual Symbol* create( const Config& conf ) = 0;

        virtual void parseSLD(const Config& c, Style& style) const = 0;
    };    

    typedef std::list< osg::ref_ptr< SymbolFactory > > SymbolFactoryList;

    /**
     * A registry of Symbol plugins
     */
    class OSGEARTHSYMBOLOGY_EXPORT SymbolRegistry : public osg::Referenced
    {         
    public:
        /**
         * The singleton instance of the factory
         */
        static SymbolRegistry* instance();

        /*
         * Adds a new SymbolFactory to the list
         */
        void add( SymbolFactory* factory );

        /**
         * Creates a Symbol with the registered plugins from the given Config
         */
        Symbol* create( const Config& conf );

        /**
         * Parses the given SLD config into the given Style using all of the registered symbols
         */
        void parseSLD(const Config& c, Style& style) const;

    protected:
        SymbolRegistry();
        SymbolFactoryList _factories;
    };

    template<class T>
    struct SimpleSymbolFactory : public SymbolFactory
    {
        SimpleSymbolFactory(const std::string& key):_key(key){}

        virtual Symbol* create(const Config& conf)
        {
            if (conf.key() == _key) return new T(conf);            
            return 0;
        }
                
        virtual void parseSLD(const Config& c, class Style& style) const
        {
            T::parseSLD( c, style );
        }

        std::string _key;
    };

    template<class T>
    struct RegisterSymbolProxy
    {
        RegisterSymbolProxy( T* factory) { SymbolRegistry::instance()->add( factory ); }
        RegisterSymbolProxy() { SymbolRegistry::instance()->add( new T ); }
    };

#define OSGEARTH_REGISTER_SYMBOL( CLASSNAME )\
    static osgEarth::Symbology::RegisterSymbolProxy<CLASSNAME> s_osgEarthRegisterSymbolProxy_##CLASSNAME;

#define OSGEARTH_REGISTER_SIMPLE_SYMBOL( KEY, CLASSNAME)\
    static osgEarth::Symbology::RegisterSymbolProxy< osgEarth::Symbology::SimpleSymbolFactory<CLASSNAME> > s_osgEarthRegisterSymbolProxy_##CLASSNAME##KEY(new osgEarth::Symbology::SimpleSymbolFactory<CLASSNAME>(#KEY));


} } // namespace osgEarth::Symbology

#endif // OSGEARTH_SYMBOLOGY_SYMBOL_H
