/* ----------------------------------------------------------------------------
 * imageloader.cpp
 *
 * Copyright (c) 2017 Yann Herklotz Grave <ymherklotz@gmail.com> -- MIT License
 * See file LICENSE for more details
 * ----------------------------------------------------------------------------
 */

#include "imageloader.hpp"
#include "iomanager.hpp"
#include "picopng.hpp"

#include <stdexcept>

namespace yage
{

Texture ImageLoader::loadPng(const std::string &file_path)
{
	Texture texture = {};

	std::vector<unsigned char> in;
	std::vector<unsigned char> out;
	unsigned long width, height;

	if(!IoManager::readFileToBuffer(file_path, in))
		throw std::runtime_error("Failed to load '"+file_path+"' to buffer");

	int error_code = decodePNG(out, width, height, &in[0], in.size());
	if(error_code != 0)
		throw std::runtime_error("Failed to load '"+file_path+"' to png with error code"+std::to_string(error_code));

	glGenTextures(1, &texture.id);
    
	glBindTexture(GL_TEXTURE_2D, texture.id);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, &out[0]);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);

	glGenerateMipmap(GL_TEXTURE_2D);

	glBindTexture(GL_TEXTURE_2D, 0);

	texture.width = (int)width;
	texture.height = (int)height;

	return texture;
}
    
} // yage