#include "texture.h"
#include "sys.h"
#include <string.h>
#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"

gl_texture_t textures[MAX_TEXTURES] = {0};

void generate_texture(gl_texture_t *texture, u32 width, u32 height, void *data)
{
	texture->width = width;
	texture->height = height;
	glGenTextures(1, &texture->id);
	glBindTexture(GL_TEXTURE_2D, texture->id);
	glTexImage2D(GL_TEXTURE_2D, 0, texture->internal_format, width, height, 0, texture->image_format, GL_UNSIGNED_BYTE, data);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, texture->wrap_s);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, texture->wrap_t);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, texture->min_filter);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, texture->mag_filter);
	glBindTexture(GL_TEXTURE_2D, 0);
}

gl_texture_t load_texture(const char *dir, const char *filename, const char *name, i32 alpha)
{
	gl_texture_t texture = {0};
	if (get_texture_id(name)) {
		info("texture with name \"%s\" already exist", name);
		return texture;
	}
	texture = (gl_texture_t)DEFAULT_TEXTURE;
	texture.name = name;
	if (alpha) {
		texture.internal_format = GL_RGBA;
		texture.image_format = GL_RGBA;
	}
	char path[512] = {0};
	snprintf(path, 512, "%s/%s", (dir ? dir : "."), filename);
	i32 width, height;
	u8 *data = stbi_load(path, &width, &height, 0, 0); 
	if (!data) {
		info("failed to load \"%s\"", path);
		return texture;
	}
	generate_texture(&texture, width, height, data);
	stbi_image_free(data);
	for (u32 i = 0; i < MAX_TEXTURES; i++) {
		if (!textures[i].name) {
			textures[i] = texture;
			info("texture \"%s\" loaded successfully", path);
			return textures[i];
		}
	}
	return texture;
}

u32 get_texture_id(const char *name)
{
	for (i32 i = 0; i < MAX_TEXTURES; i++)
		if (textures[i].name && strstr(textures[i].name, name))
			return textures[i].id;
	return 0;
}

v2 get_texture_size(const char *name)
{
	for (i32 i = 0; i < MAX_TEXTURES; i++)
		if (textures[i].name && strstr(textures[i].name, name))
			return (v2){textures[i].width, textures[i].height};
	return (v2){0.0f, 0.0f};
}