/* -*-c++-*- */
/* osgEarth - Geospatial SDK for OpenSceneGraph
 * Copyright 2020 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_TILECACHE_H
#define OSGEARTH_TILECACHE_H

#include <osgEarth/Common>
#include <osgEarth/ImageLayer>
#include <osgEarth/ElevationLayer>
#include <osgEarth/URI>

/**
 * TileCache - an implementation of a WMS-C compliant server
 * made available under the BSD license by MetaCarta.
 * http://tilecache.org/
 */

//! TMS namespace contains TMS support classes used to the Layers
namespace osgEarth { namespace TileCache
{
    /**
     * Underlying TMS driver that does the actual TMS I/O
     */
    class OSGEARTH_EXPORT Driver
    {
    public:
        Status open(
            const URI& uri,
            const osgDB::Options* readOptions);

        ReadResult read(
            const URI& uri,
            const TileKey& key,
            const std::string& layer,
            const std::string& format,
            ProgressCallback* progress,
            const osgDB::Options* readOptions) const;
    };

    /**
     * Serialization TileCache shared options
     */
    class OSGEARTH_EXPORT Options
    {
    public:
        OE_OPTION(URI, url);
        OE_OPTION(std::string, layer);
        OE_OPTION(std::string, format);
        void writeTo(Config& conf) const;
        void readFrom(const Config& conf);
    };
} }

//........................................................................

namespace osgEarth
{
    /**
     * Image layer connected to a TMS (Tile Map Service) facility
     */
    class OSGEARTH_EXPORT TileCacheImageLayer : public ImageLayer
    {
    public: // serialization
        class OSGEARTH_EXPORT Options : public ImageLayer::Options, public TileCache::Options {
        public:
            META_LayerOptions(osgEarth, Options, ImageLayer::Options);
            virtual Config getConfig() const;
        private:
            void fromConfig(const Config& conf);
        };

    public:
        META_Layer(osgEarth, TileCacheImageLayer, Options, ImageLayer, TileCacheImage);

    public:
        //! Base URL of TileCache endpoint
        void setURL(const URI& value);
        const URI& getURL() const;

        //! Data format to request from the service
        void setLayer(const std::string& value);
        const std::string& getLayer() const;

        //! Data format to request from the service
        void setFormat(const std::string& value);
        const std::string& getFormat() const;

    public: // Layer
        
        //! Establishes a connection to the TMS repository
        virtual Status openImplementation();

        //! Creates a raster image for the given tile key
        virtual GeoImage createImageImplementation(const TileKey& key, ProgressCallback* progress) const;

    protected: // Layer

        //! Called by constructors
        virtual void init();

    protected:

        //! Destructor
        virtual ~TileCacheImageLayer() { }

    private:
        TileCache::Driver _driver;
    };


    /**
     * Elevation layer connected to a TMS (Tile Map Service) facility
     */
    class OSGEARTH_EXPORT TileCacheElevationLayer : public ElevationLayer
    {
    public: // serialization
        class OSGEARTH_EXPORT Options : public ElevationLayer::Options, public TileCache::Options {
        public:
            META_LayerOptions(osgEarth, Options, ElevationLayer::Options);
            virtual Config getConfig() const;
        private:
            void fromConfig(const Config& conf);
        };

    public:
        META_Layer(osgEarth, TileCacheElevationLayer, Options, ElevationLayer, TileCacheElevation);
        
        //! Base URL of TileCache endpoint
        void setURL(const URI& value);
        const URI& getURL() const;

        //! Data format to request from the service
        void setLayer(const std::string& value);
        const std::string& getLayer() const;

        //! Data format to request from the service
        void setFormat(const std::string& value);
        const std::string& getFormat() const;

    public: // Layer
        
        //! Establishes a connection to the TMS repository
        virtual Status openImplementation();

        //! Creates a heightfield for the given tile key
        virtual GeoHeightField createHeightFieldImplementation(const TileKey& key, ProgressCallback* progress) const;

    protected: // Layer

        //! Called by constructors
        virtual void init();

    protected:

        //! Destructor
        virtual ~TileCacheElevationLayer() { }

    private:
        osg::ref_ptr<TileCacheImageLayer> _imageLayer;
    };
} // namespace osgEarth

OSGEARTH_SPECIALIZE_CONFIG(osgEarth::TileCacheImageLayer::Options);
OSGEARTH_SPECIALIZE_CONFIG(osgEarth::TileCacheElevationLayer::Options);

#endif // OSGEARTH_TMS_H