/* -*-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/Symbol>
#include <osgEarth/Expression>

namespace osgEarth
{
    using namespace osgEarth;

    /**
     * Symbol that directs the GeometryCompiler to create extruded 3D geometry
     * from 2D vector data.
     */
    class OSGEARTH_EXPORT ExtrusionSymbol : public Symbol
    {
    public:
        META_Object(osgEarth, ExtrusionSymbol);

        ExtrusionSymbol(const ExtrusionSymbol& rhs,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
        ExtrusionSymbol( const Config& conf =Config() );

        /** dtor */
        virtual ~ExtrusionSymbol() { }

        /** Height to which to extrude geometry above the footprint (for HEIGHT_REFERENCE_Z)
            or above MSL (for HEIGHT_REFERENCE_MSL) */
        optional<float>& height() { return _height; }
        const optional<float>& height() const { return _height; }

        /** Simple expression to evaluate to get height */
        optional<NumericExpression>& heightExpression() { return _heightExpr; }
        const optional<NumericExpression>& heightExpression() const { return _heightExpr; }

        /** Whether the top cap of the extruded geometry should be flat (default=true) */
        optional<bool>& flatten() { return _flatten; }
        const optional<bool>& flatten() const { return _flatten; }

        /** Name of a style describing how to symbolize the extruded walls */
        optional<std::string>& wallStyleName() { return _wallStyleName; }
        const optional<std::string>& wallStyleName() const { return _wallStyleName; }

        /** Name of a style describing how to symbolize the elevated rooftop */
        optional<std::string>& roofStyleName() { return _roofStyleName; }
        const optional<std::string>& roofStyleName() const { return _roofStyleName; }

        /** Percentage by which to darken the color of the bottom of the walls relative
            to the main wall color (default = 0.0, range = [0..1]) */
        optional<float>& wallGradientPercentage() { return _wallGradientPercentage; }
        const optional<float>& wallGradientPercentage() const { return _wallGradientPercentage; }

        /** Percentage by which to shade the wells to simulate lighting [0..1] */
        optional<float>& wallShadePercentage() { return _wallShadePercentage; }
        const optional<float>& wallShadePercentage() const { return _wallShadePercentage; }
        
    public:
        virtual Config getConfig() const;
        virtual void mergeConfig( const Config& conf );
        static void parseSLD(const Config& c, class Style& style);

    protected:
        optional<float>             _height;
        optional<bool>              _flatten;
        optional<NumericExpression> _heightExpr;
        optional<std::string>       _wallStyleName;
        optional<std::string>       _roofStyleName;
        optional<float>             _wallGradientPercentage;
        optional<float>             _wallShadePercentage;
    };
} // namespace osgEarth