#include <stdlib.h>
#include <stdbool.h>
#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <lua.h>
#include <lauxlib.h>
#include "util/util.h"
#include "gl.h"

/* needs to be here because glad uses macros to define glBufferData */
#ifdef HONEY_TEST_H
#undef glBufferData
#define glBufferData mock_glBufferData_
#endif


int gl_init(lua_State *L);
int glad_init(lua_State *L);
int gl_terminate(lua_State *L);
int gl_get_error(lua_State *L);
int gl_enable(lua_State *L);
int gl_disable(lua_State *L);

void setup_gl(lua_State *L, int honey_index)
{
	struct honey_tbl_t tbl[] = {
		/* functions */
		H_FUNC("Init", gl_init),
		H_FUNC("InitGlad", glad_init),
		H_FUNC("Terminate", gl_terminate),
		H_FUNC("GetError", gl_get_error),
		H_FUNC("Enable", gl_enable),
		H_FUNC("Disable", gl_disable),

		/******** enums ********/
		/* data types */
		H_INT("UNSIGNED_BYTE", GL_UNSIGNED_BYTE),
		H_INT("UNSIGNED_INT", GL_UNSIGNED_INT),
		H_INT("INT", GL_INT),
		H_INT("FLOAT", GL_FLOAT),

		/* error types */
		H_INT("NO_ERROR", GL_NO_ERROR),
		H_INT("INVALID_ENUM", GL_INVALID_ENUM),
		H_INT("INVALID_VALUE", GL_INVALID_VALUE),
		H_INT("INVALID_OPERATION", GL_INVALID_OPERATION),
		H_INT("INVALID_FRAMEBUFFER_OPERATION", GL_INVALID_FRAMEBUFFER_OPERATION),
		H_INT("OUT_OF_MEMORY", GL_OUT_OF_MEMORY),

		/* opengl capabilities */
		H_INT("DEPTH_TEST", GL_DEPTH_TEST),
		H_INT("CULL_FACE", GL_CULL_FACE),

		H_END
	};
	create_table(L, tbl);
	int gl_index = lua_gettop(L);

	setup_shader(L, gl_index);
	setup_drawing(L, gl_index);
	setup_data(L, gl_index);
	setup_texture(L, gl_index);

	lua_setfield(L, honey_index, "gl");
}


int gl_init(lua_State *L)
{
	if (!glfwInit()) {
		luaL_error(L, "failed to initialize GLFW");
	}
	return 0;
}


int glad_init(lua_State *L)
{
	if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
		luaL_error(L, "failed to initialize GLAD");
	}
}


int gl_terminate(lua_State *L)
{
	glfwTerminate();
	return 0;
}


int gl_get_error(lua_State *L)
{
	lua_pushinteger(L, glGetError());
	return 1;
}


int gl_enable(lua_State *L)
{
	lua_Integer cap = luaL_checkinteger(L, 1);
	glEnable(cap);
	return 0;
}


int gl_disable(lua_State *L)
{
	lua_Integer cap = luaL_checkinteger(L, 1);
	glDisable(cap);
	return 0;
}