/*****************************************************************************
 * 
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2006 Artem Pavlenko
 *
 * This library 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 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/

//$Id: datasource.hpp 43 2005-04-22 18:52:47Z pavlenko $

#ifndef DATASOURCE_HPP
#define DATASOURCE_HPP

#include <map>
#include <string>
#include "ctrans.hpp"
#include "params.hpp"
#include "feature.hpp"
#include "query.hpp"
#include "feature_layer_desc.hpp"

#include <boost/shared_ptr.hpp>

namespace mapnik
{    
    typedef MAPNIK_DECL shared_ptr<Feature> feature_ptr;
    struct MAPNIK_DECL Featureset
    {
        virtual feature_ptr next()=0;
        virtual ~Featureset() {};
    };
    
    typedef shared_ptr<Featureset> featureset_ptr;    
    class MAPNIK_DECL datasource_exception : public std::exception
    {
    private:
        const std::string message_;
    public:
        datasource_exception(const std::string& message=std::string())
            :message_(message) {}

        ~datasource_exception() throw() {}
        virtual const char* what() const throw()
        {
            return message_.c_str();
        }
    };
    
    class MAPNIK_DECL datasource : private boost::noncopyable
    {
        parameters params_;
    public:        
        enum {
            Vector,
            Raster
        };
        
        datasource (parameters const& params)
            : params_(params) {}

        parameters const& params() const
        {
            return params_;
        }
        
        virtual int type() const=0;
        virtual featureset_ptr features(const query& q) const=0;
        virtual Envelope<double> const& envelope() const=0;
        virtual layer_descriptor const& get_descriptor() const=0;
        virtual ~datasource() {};
    };
    
    typedef std::string datasource_name();
    typedef datasource* create_ds(const parameters& params);
    typedef void destroy_ds(datasource *ds);

    
    class datasource_deleter
    {
    public:
        void operator() (datasource* ds)
        {
            delete ds;
        }
    };

    typedef boost::shared_ptr<datasource> datasource_p;
    
    ///////////////////////////////////////////
#define DATASOURCE_PLUGIN(classname)                                    \
    extern "C" MAPNIK_DECL std::string datasource_name()                \
    {                                                                   \
        return classname::name();                                       \
    }                                                                   \
        extern "C"  MAPNIK_DECL datasource* create(const parameters &params) \
        {                                                               \
            return new classname(params);                               \
        }                                                               \
        extern "C" MAPNIK_DECL void destroy(datasource *ds)             \
        {                                                               \
            delete ds;                                                  \
        }                                                               \
        ///////////////////////////////////////////
}
#endif                                            //DATASOURCE_HPP