//
//  Renderer.h
//
//  General rendering functions.
//

#pragma once
#ifndef ES_CORE_RENDERER_RENDERER_H
#define ES_CORE_RENDERER_RENDERER_H

#include "math/Vector2f.h"

class  Transform4x4f;
class  Vector2i;
struct SDL_Window;

namespace Renderer
{
    namespace Blend
    {
        enum Factor {
            ZERO = 0,
            ONE = 1,
            SRC_COLOR = 2,
            ONE_MINUS_SRC_COLOR = 3,
            SRC_ALPHA = 4,
            ONE_MINUS_SRC_ALPHA = 5,
            DST_COLOR = 6,
            ONE_MINUS_DST_COLOR = 7,
            DST_ALPHA = 8,
            ONE_MINUS_DST_ALPHA = 9
        };
    }

    namespace Texture
    {
        enum Type {
            RGBA  = 0,
            ALPHA = 1
        };
    }

    struct Rect {
        Rect(
                const int _x,
                const int _y,
                const int _w,
                const int _h)
                : x(_x),
                y(_y),
                w(_w),
                h(_h) {}
        int x;
        int y;
        int w;
        int h;
    };

    struct Vertex
    {
        Vertex() {}
        Vertex(
                const Vector2f& _pos,
                const Vector2f& _tex,
                const unsigned int _col)
                : pos(_pos),
                tex(_tex),
                col(_col) { }
        Vector2f pos;
        Vector2f tex;
        unsigned int col;
    };

    bool init();
    void deinit();
    void pushClipRect(const Vector2i& _pos, const Vector2i& _size);
    void popClipRect();
    void drawRect(
            const float _x,
            const float _y,
            const float _w,
            const float _h,
            const unsigned int _color,
            const unsigned int _colorEnd,
            bool horizontalGradient = false,
            const Blend::Factor _srcBlendFactor = Blend::SRC_ALPHA,
            const Blend::Factor _dstBlendFactor = Blend::ONE_MINUS_SRC_ALPHA);
    SDL_Window* getSDLWindow();
    int getWindowWidth();
    int getWindowHeight();
    int getScreenWidth();
    int getScreenHeight();
    int getScreenOffsetX();
    int getScreenOffsetY();
    int getScreenRotate();

    // API specific.
    unsigned int convertColor(const unsigned int _color);
    unsigned int getWindowFlags();
    void setupWindow();
    void createContext();
    void destroyContext();
    unsigned int createTexture(
            const Texture::Type _type,
            const bool _linear,
            const bool _repeat,
            const unsigned int _width,
            const unsigned int _height,
            void* _data);
    void destroyTexture(const unsigned int _texture);
    void updateTexture(
            const unsigned int _texture,
            const Texture::Type _type,
            const unsigned int _x,
            const unsigned _y,
            const unsigned int _width,
            const unsigned int _height,
            void* _data);
    void bindTexture(const unsigned int _texture);
    void drawLines(
            const Vertex* _vertices,
            const unsigned int _numVertices,
            const Blend::Factor _srcBlendFactor = Blend::SRC_ALPHA,
            const Blend::Factor _dstBlendFactor = Blend::ONE_MINUS_SRC_ALPHA);
    void drawTriangleStrips(
            const Vertex* _vertices,
            const unsigned int _numVertices,
            const Blend::Factor _srcBlendFactor = Blend::SRC_ALPHA,
            const Blend::Factor _dstBlendFactor = Blend::ONE_MINUS_SRC_ALPHA);
    void setProjection(const Transform4x4f& _projection);
    void setMatrix(const Transform4x4f& _matrix);
    void setViewport(const Rect& _viewport);
    void setScissor(const Rect& _scissor);
    void setSwapInterval();
    void swapBuffers();

}

#endif // ES_CORE_RENDERER_RENDERER_H