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


int gl_texture_create(lua_State *L);
int gl_texture_bind(lua_State *L);
int gl_texture_image_2d(lua_State *L);
int gl_texture_generate_mipmaps(lua_State *L);
int gl_texture_set_active(lua_State *L);
int gl_tex_parameter_i(lua_State *L);


void setup_texture(lua_State *L, int gl_index)
{
	struct honey_tbl_t tbl[] = {
		/* functions */
		H_FUNC("GenTextures", gl_texture_create),
		H_FUNC("BindTexture", gl_texture_bind),
		H_FUNC("TexImage2D", gl_texture_image_2d),
		H_FUNC("GenerateMipmap", gl_texture_generate_mipmaps),
		H_FUNC("ActiveTexture", gl_texture_set_active),
		H_FUNC("TexParameteri", gl_tex_parameter_i),

		/******** enums ********/
		/* texture binding targets */
		H_INT("TEXTURE_2D", GL_TEXTURE_2D),

		/* texture data formats */
		H_INT("RGB", GL_RGB),
		H_INT("RGBA", GL_RGBA),

		/* texture parameters */
		H_INT("TEXTURE_WRAP_S", GL_TEXTURE_WRAP_S),
		H_INT("TEXTURE_WRAP_T", GL_TEXTURE_WRAP_T),
		H_INT("TEXTURE_MIN_FILTER", GL_TEXTURE_MIN_FILTER),
		H_INT("TEXTURE_MAG_FILTER", GL_TEXTURE_MAG_FILTER),
		H_INT("TEXTURE_SWIZZLE_R", GL_TEXTURE_SWIZZLE_R),
		H_INT("TEXTURE_SWIZZLE_G", GL_TEXTURE_SWIZZLE_G),
		H_INT("TEXTURE_SWIZZLE_B", GL_TEXTURE_SWIZZLE_B),
		H_INT("TEXTURE_SWIZZLE_A", GL_TEXTURE_SWIZZLE_A),

		/* wrapping types */
		H_INT("REPEAT", GL_REPEAT),

		/* filter types */
		H_INT("NEAREST", GL_NEAREST),
		H_INT("LINEAR", GL_LINEAR),

		/* swizzle targets */
		H_INT("RED", GL_RED),
		H_INT("GREEN", GL_GREEN),
		H_INT("BLUE", GL_BLUE),
		H_INT("ALPHA", GL_ALPHA),
		H_INT("ZERO", GL_ZERO),
		H_INT("ONE", GL_ONE),

		H_END
	};
	create_table(L, tbl);
	append_table(L, gl_index, lua_gettop(L));
	lua_pop(L, 1);
}


int gl_texture_create(lua_State *L)
{
	unsigned int texture;
	glGenTextures(1, &texture);
	lua_pushinteger(L, texture);
	return 1;
}


int gl_texture_bind(lua_State *L)
{
	lua_Integer target, texture;
	target = luaL_checkinteger(L, 1);
	texture = luaL_checkinteger(L, 2);
	glBindTexture(target, texture);
	return 0;
}


int gl_texture_image_2d(lua_State *L)
{
	lua_Integer target, mipmap_level,
	            internal_format,
	            width, height,
	            format, type;
	target = luaL_checkinteger(L, 1);
	mipmap_level = luaL_checkinteger(L, 2);
	internal_format = luaL_checkinteger(L, 3);
	width = luaL_checkinteger(L, 4);
	height = luaL_checkinteger(L, 5);
	format = luaL_checkinteger(L, 6);
	type = luaL_checkinteger(L, 7);
	void *data = lua_touserdata(L, 8);

	glTexImage2D(target, mipmap_level, internal_format, width, height, 0, format, type, data);
	return 0;
}


int gl_texture_generate_mipmaps(lua_State *L)
{
	lua_Integer target = luaL_checkinteger(L, 1);
	glGenerateMipmap(target);
	return 0;
}


int gl_texture_set_active(lua_State *L)
{
	lua_Integer unit = luaL_checkinteger(L, 1);
	glActiveTexture(GL_TEXTURE0 + unit);
	return 0;
}


int gl_tex_parameter_i(lua_State *L)
{
	lua_Integer target, pname, param;
	target = luaL_checkinteger(L, 1);
	pname = luaL_checkinteger(L, 2);
	param = luaL_checkinteger(L, 3);
	glTexParameteri(target, pname, param);
	return 0;
}