//
//  Drawer.h
//  OSXGLEssentials
//
//  Created by Joshua Moerman on 10/03/14.
//
//

#pragma once

#include <Box2D/Box2D.h>

#include <moggle/core/gl.hpp>
#include <moggle/math/matrix.hpp>
#include <moggle/core/shader.hpp>

#include <vector>

struct Vertex {
    using Position = moggle::vector3<float>;
    using Color = moggle::vector3<float>;
    
    Position position;
    Color color;
};

inline moggle::vector3<float> convert(b2Vec2 const & p){ return {p.x, p.y, 0.0f}; }
inline moggle::vector3<float> convert(b2Color const & p){ return {p.r, p.g, p.b}; }

struct Drawer : b2Draw {
    // camera position
    Vertex::Position camera = {0, 0};
    
    // print debugging info
    bool verbose = false;
    
    // bundle needed to load shaders
    Drawer(std::string const & bundle);
    
    // draw buffer
    void draw();
    
    // clear buffer
    void clear();
    
    // resize any stuff
    void resize(float width, float height);
    
    // Box 2D drawing interface
    // Implementation will fill its buffers
	virtual void DrawPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color) override;
	virtual void DrawSolidPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color) override;
	virtual void DrawCircle(const b2Vec2& center, float32 radius, const b2Color& color) override;
	virtual void DrawSolidCircle(const b2Vec2& center, float32 radius, const b2Vec2& axis, const b2Color& color) override;
	virtual void DrawSegment(const b2Vec2& p1, const b2Vec2& p2, const b2Color& color) override;
	virtual void DrawTransform(const b2Transform& xf) override;

private:
    moggle::shader_program program;
    moggle::matrix4<float> projection;
    std::vector<Vertex> segments;
    std::vector<GLuint> sizes;
    GLuint vao, buf;
};