/* -*-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/>
 */
#pragma once
#include <osgEarth/Common>
#include <osgEarth/Profile>
#include <osgEarth/Geometry>
#include <osgEarth/Style>
#include <osgEarth/GeoCommon>
#include <osgEarth/SpatialReference>
#include <osg/Array>
#include <osg/Shape>
#include <map>
#include <list>
#include <vector>

namespace osgEarth
{
    namespace Util
    {
        class FilterContext;
        class Session;
    }

    /**
     * Metadata and schema information for feature data.
     */
    class OSGEARTH_EXPORT FeatureProfile : public osg::Referenced
    {
    public:
        //! Construct a non-tiled feature profile with an extent
        FeatureProfile(const GeoExtent& featuresExtent);

        //! Construct a TILED feature profile with a tiling schema
        FeatureProfile(const Profile* tilingProfile);

        //! Copy ctor
        FeatureProfile(const FeatureProfile& rhs);

        //! Spatial extents of the features data
        void setExtent(const GeoExtent& value) { _extent = value; }
        const GeoExtent& getExtent() const { return _extent; }

        //! Spatial reference system of feature data
        const SpatialReference* getSRS() const { return _extent.getSRS(); }

        //! Whether the feature data is pre-tiled
        bool isTiled() const;

        //! For tiled data, the tiling profile
        const osgEarth::Profile* getTilingProfile() const;
        void setTilingProfile( const osgEarth::Profile* profile );

        //! For tiled data, the first tiling level of detail
        int getFirstLevel() const;
        void setFirstLevel(int firstLevel );

        //! For tiled data, the last tiling level fo detail
        int getMaxLevel() const;
        void setMaxLevel(int maxLevel);

        //! Interpolation method for geodetic data
        optional<GeoInterpolation>& geoInterp() { return _geoInterp; }
        const optional<GeoInterpolation>& geoInterp() const { return _geoInterp; }

    protected:
        virtual ~FeatureProfile() { }

        osg::ref_ptr< const osgEarth::Profile > _tilingProfile;
        GeoExtent _extent;
        int _firstLevel;
        int _maxLevel;
        optional<GeoInterpolation> _geoInterp;
    };

    struct AttributeValueUnion
    {
        std::string stringValue;
        double doubleValue;
        long long intValue;
        bool boolValue;
        std::vector<double> doubleArrayValue;
        bool set = false;
    };

    enum AttributeType
    {
        ATTRTYPE_UNSPECIFIED,
        ATTRTYPE_STRING,
        ATTRTYPE_INT,
        ATTRTYPE_DOUBLE,
        ATTRTYPE_BOOL,
        ATTRTYPE_DOUBLEARRAY
    };

    struct OSGEARTH_EXPORT AttributeValue
    {
        AttributeType type;
        AttributeValueUnion value;
        std::string getString() const;
        double getDouble(double defaultValue = 0.0) const;
        long long getInt(long long defaultValue = 0) const;
        bool getBool(bool defaultValue = false) const;
        const std::vector<double>& getDoubleArrayValue() const;
    };

    using AttributeTable = vector_map<std::string, AttributeValue, ci_string_less>;

    using FeatureID = std::int64_t; // long long;

    using FeatureSchema = std::map<std::string, AttributeType>;

    class Feature;

    using FeatureList = std::vector<osg::ref_ptr<Feature>>;

    /**
     * Basic building block of vector feature data.
     */
    class OSGEARTH_EXPORT Feature : public osg::Referenced // : public osg::Object
    {
    public:

        //! Construct a feature
        Feature(Geometry* geom, const SpatialReference* srs, const Style& style =Style(), FeatureID fid =0LL );

        //! Construct a feature (copy)
        Feature(const Feature& rhs);

        //! Contruct a feature (move)
        Feature(Feature&& rhs);

    public:

        /**
         * The unique ID of this feature (unique relative to its provider)
         */
        FeatureID getFID() const;

        /**
         * Set the FID of this feature.
         */
        void setFID(FeatureID fid);

        /**
         * Gets the GeoExtent of this Feature
         */
        GeoExtent getExtent() const;

        /**
         * The geometry in this feature.
         */
        void setGeometry( Geometry* geom );
        Geometry* getGeometry() { dirty(); return _geom.get(); }
        const Geometry* getGeometry() const { return _geom.get(); }

        /**
         * The spatial reference of the geometry in this feature.
         */
        const SpatialReference* getSRS() const { return _srs.get(); }
        void setSRS( const SpatialReference* srs );

        /**
         * Computes the bound of this feature in the specified SRS.
         */
        bool getWorldBound( const SpatialReference* srs, osg::BoundingSphered& out_bound ) const;

        /**
         * Gets a polytope, in world coordinates (proj or ECEF) that bounds the
         * geographic extents covered by this feature. This is useful for roughly
         * intersecting the feature with the terrain graph.
         */
        bool getWorldBoundingPolytope( const SpatialReference* srs, osg::Polytope& out_polytope ) const;

        /**
         * Gets a polytope, in world coordinates (proj or ECEF) that bounds the
         * world coordinates covered by the given bounding sphere. This is useful for roughly
         * intersecting features with the terrain graph.
         */
        static bool getWorldBoundingPolytope( const osg::BoundingSphered& bs, const SpatialReference* srs, osg::Polytope& out_polytope );

        /**
         * Calculates the extent of this feature.
         */
        GeoExtent calculateExtent() const;


        const AttributeTable& getAttrs() const { return _attrs; }

        void set( const std::string& name, const std::string& value );
        void set( const std::string& name, double value );
        void set(const std::string& name, int value);
        void set( const std::string& name, long long value );
        void set( const std::string& name, bool value );
        void set( const std::string& name, const std::vector<double>& value );
        void setSwap( const std::string& name, std::vector<double>& value );
        void set( const std::string& name, const AttributeValue& value);

        /** Sets the attribute to NULL */
        void setNull( const std::string& name );
        void setNull( const std::string& name, AttributeType type );

        void removeAttribute(const std::string& name);

        bool hasAttr( const std::string& name ) const;

        std::string getString( const std::string& name ) const;
        double getDouble( const std::string& name, double defaultValue =0.0 ) const;
        long long getInt( const std::string& name, long long defaultValue =0 ) const;
        bool getBool( const std::string& name, bool defaultValue =false ) const;
        const std::vector<double>* getDoubleArray( const std::string& name ) const;

        /**
         * Gets whether the attribute is set, meaning it is non-NULL
         */
        bool isSet( const std::string& name ) const;

        /** Embedded style. */
        optional<Style>& style() { return _style; }
        const optional<Style>& style() const { return _style; }

        /** Geodetic interpolation method. */
        optional<GeoInterpolation>& geoInterp() { dirty(); return _geoInterp; }
        const optional<GeoInterpolation>& geoInterp() const { return _geoInterp; }

        /** populates the variables of an expression with attribute values and evals the expression. */
        double eval(NumericExpression& expr, const FilterContext* context) const;
        double eval(NumericExpression& expr, Session* session) const;

        /** populates the variables of an expression with attribute values and evals the expression. */
        const std::string& eval(StringExpression& expr, const FilterContext* context) const;
        const std::string& eval(StringExpression& expr, Session* session) const;

    public:
        /** Gets a GeoJSON representation of this Feature */
        std::string getGeoJSON() const;

        /** Gets a FeatureList as a GeoJSON FeatureCollection */
        static std::string featuresToGeoJSON(const FeatureList& features);

    public:
        /**
         * Transforms this Feature to the given SpatialReference
         */
        void transform( const SpatialReference* srs );

        /**
         * Splits this feature into multiple features if it is a geodetic feature and cross the date line.
         */
        void splitAcrossDateLine(FeatureList& splitFeatures);

    protected:

        Feature();
        Feature( FeatureID fid );

        virtual ~Feature();

        FeatureID                            _fid;
        osg::ref_ptr<Geometry>               _geom;
        osg::ref_ptr<const SpatialReference> _srs;
        AttributeTable                       _attrs;
        optional<Style>                      _style;
        optional<GeoInterpolation>           _geoInterp;
        GeoExtent                            _cachedExtent;

        void dirty();
    };

} // namespace osgEarth