/*****************************************************************************************
 *                                                                                       *
 * OpenSpace                                                                             *
 *                                                                                       *
 * Copyright (c) 2014-2023                                                               *
 *                                                                                       *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
 * software and associated documentation files (the "Software"), to deal in the Software *
 * without restriction, including without limitation the rights to use, copy, modify,    *
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
 * permit persons to whom the Software is furnished to do so, subject to the following   *
 * conditions:                                                                           *
 *                                                                                       *
 * The above copyright notice and this permission notice shall be included in all copies *
 * or substantial portions of the Software.                                              *
 *                                                                                       *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
 * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
 ****************************************************************************************/

#ifndef __OPENSPACE_MODULE_SPACE___RENDERABLETRAVELSPEED___H__
#define __OPENSPACE_MODULE_SPACE___RENDERABLETRAVELSPEED___H__

#include <openspace/rendering/renderable.h>

#include <openspace/properties/scalar/intproperty.h>
#include <openspace/properties/scalar/floatproperty.h>
#include <openspace/properties/vector/vec3property.h>
#include <ghoul/opengl/uniformcache.h>

namespace openspace {

class SceneGraphNode;

namespace documentation { struct Documentation; }

class RenderableTravelSpeed : public Renderable {
public:
    RenderableTravelSpeed(const ghoul::Dictionary& dictionary);

    static documentation::Documentation Documentation();
    void initializeGL() override;
    void initialize() override;
    void deinitializeGL() override;

    bool isReady() const override;

    void render(const RenderData& data, RendererTasks& rendererTask) override;
    void update(const UpdateData& data) override;

private:
    double calculateLightTravelTime(glm::dvec3 startPosition, glm::dvec3 targetPosition);
    void calculateVerticesPositions();
    void calculateDirectionVector();
    void updateVertexData();
    void reinitiateTravel();
    UniformCache(lineColor, opacity) _uniformCache;

    properties::StringProperty _targetName;
    SceneGraphNode* _targetNode = nullptr;
    properties::DoubleProperty _travelSpeed;
    properties::FloatProperty _indicatorLength;
    properties::FloatProperty _fadeLength;
    properties::FloatProperty _lineWidth;
    properties::Vec3Property _lineColor;

    struct VertexPositions {
        glm::vec3 endOfFade;
        glm::vec3 betweenLightAndFade;
        glm::vec3 headOfLight;
    };
    VertexPositions _vertexPositions;

    glm::dvec3 _sourcePosition;
    glm::dvec3 _targetPosition;
    double _lightTravelTime;
    glm::dvec3 _directionVector;
    double _initiationTime = -1.0;
    double _arrivalTime;
    double _timeSinceStart = -1.0;

    ghoul::opengl::ProgramObject* _shaderProgram = nullptr;
    // The vertex attribute location for position
    // must correlate to layout location in vertex shader
    GLuint _vaoId = 0;
    GLuint _vBufferId = 0;
};

} // namespace openspace

#endif // __OPENSPACE_MODULE_SPACE___RENDERABLETRAVELSPEED___H__
