#pragma once

#include "resources.h"

#define CANVAS_ZOOM_MIN 1.0f
#define CANVAS_ZOOM_MAX 2000.0f
#define CANVAS_ZOOM_DEFAULT 100.0f
#define CANVAS_ZOOM_STEP 100.0f
#define CANVAS_GRID_MIN 1
#define CANVAS_GRID_MAX 1000
#define CANVAS_GRID_DEFAULT 32

const inline vec2 CANVAS_PIVOT_SIZE = {4, 4};
const inline vec2 CANVAS_SCALE_DEFAULT = {1.0f, 1.0f};

const inline f32 CANVAS_AXIS_VERTICES[] = {-1.0f, 1.0f};

const inline f32 CANVAS_GRID_VERTICES[] =
{
   -1.0f, -1.0f,
    3.0f, -1.0f,
   -1.0f,  3.0f
};

const inline f32 CANVAS_RECT_VERTICES[] =
{
    0, 0,  
    1, 0,  
    1, 1,  
    0, 1  
};

const inline f32 CANVAS_TEXTURE_VERTICES[] = 
{
    0, 0, 0.0f, 0.0f,
    1, 0, 1.0f, 0.0f,
    1, 1, 1.0f, 1.0f,
    0, 1, 0.0f, 1.0f
};

struct Canvas
{
    GLuint fbo{};
    GLuint rbo{};
    GLuint axisVAO{};
    GLuint axisVBO{};
    GLuint rectVAO{};
    GLuint rectVBO{};
    GLuint gridVAO{};
    GLuint gridVBO{};
    GLuint framebuffer{};
    GLuint textureVAO{};
    GLuint textureVBO{};
    GLuint textureEBO{};
    ivec2 size{};
    ivec2 previousSize{};
    bool isInit = false;
};

#define UV_VERTICES(uvMin, uvMax) \
{ \
  0, 0, uvMin.x, uvMin.y, \
  1, 0, uvMax.x, uvMin.y, \
  1, 1, uvMax.x, uvMax.y, \
  0, 1, uvMin.x, uvMax.y  \
}

#define ATLAS_UV_MIN(type) (ATLAS_POSITION(type) / TEXTURE_ATLAS_SIZE)
#define ATLAS_UV_MAX(type) ((ATLAS_POSITION(type) + ATLAS_SIZE(type)) / TEXTURE_ATLAS_SIZE)
#define ATLAS_UV_ARGS(type) ATLAS_UV_MIN(type), ATLAS_UV_MAX(type)
#define ATLAS_UV_VERTICES(type) UV_VERTICES(ATLAS_UV_MIN(type), ATLAS_UV_MAX(type))

mat4 canvas_transform_get(Canvas* self, vec2 pan, f32 zoom, OriginType origin);
void canvas_axes_draw(Canvas* self, GLuint& shader, mat4& transform, vec4& color);
void canvas_bind(Canvas* self);
void canvas_clear(vec4& color);
void canvas_draw(Canvas* self);
void canvas_free(Canvas* self);
void canvas_grid_draw(Canvas* self, GLuint& shader, mat4& transform, ivec2& size, ivec2& offset, vec4& color);
void canvas_init(Canvas* self, const ivec2& size);
void canvas_rect_draw(Canvas* self, const GLuint& shader, const mat4& transform, const vec4& color);
void canvas_framebuffer_resize_check(Canvas* self);
void canvas_unbind(void);
void canvas_viewport_set(Canvas* self);

void canvas_texture_draw
(
    Canvas* self, 
    GLuint& shader, 
    GLuint& texture, 
    mat4& transform, 
    const f32* vertices = CANVAS_TEXTURE_VERTICES, 
    vec4 tint = COLOR_OPAQUE, 
    vec3 colorOffset = COLOR_OFFSET_NONE
);