/**

 * ShaderShark

 * Copyright © 2023 František Kučera (Frantovo.cz, GlobalCode.info)

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, version 3 of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program. If not, see <http://www.gnu.org/licenses/>.

 */

#include <string>

#include <stdexcept>

#include "opengl.h"

#include "Texture.h"

class Texture::Impl {

public:

	GLuint id;

	std::string fileName;

	int width;

	int height;

	GLfloat scale = 1.;

};

Texture::Texture(

		int width,

		int height,

		const Buffer& img,

		const std::string& fileName) : impl(new Impl()) {

	impl->fileName = fileName;

	glGenTextures(1, &impl->id);

	update(width, height, img);

}

Texture::~Texture() {

	glDeleteTextures(1, &impl->id);

	delete impl;

}

GLuint Texture::getId() const {

	return impl->id;

}

const std::string Texture::getFileName() const {

	return impl->fileName;

}

int Texture::getWidth() const {

	return impl->width;

}

int Texture::getHeight() const {

	return impl->height;

}

GLfloat Texture::getRatio() const {

	return (GLfloat) impl->width / (GLfloat) impl->height;

}

GLfloat Texture::getScale() const {

	return impl->scale;

}

void Texture::setScale(GLfloat scale) {

	impl->scale = scale;

}

void Texture::update(int width, int height, const Buffer& img) {

	impl->width = width;

	impl->height = height;

	if (img.getSize() != impl->width * impl->height * 4)

		throw std::invalid_argument("invalid image size");

	glBindTexture(GL_TEXTURE_2D, impl->id);

	auto GLT2D = GL_TEXTURE_2D;

	glTexImage2D(GLT2D, 0, GL_RGBA,

			impl->width, impl->height,

			0, GL_RGBA, GL_UNSIGNED_BYTE,

			img.getData());

	glTexParameteri(GLT2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

	glTexParameteri(GLT2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

	glTexParameteri(GLT2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // blurry upscale

	glTexParameteri(GLT2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); // sharp upscale

	glTexParameteri(GLT2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);

	glGenerateMipmap(GLT2D);

	checkError(&std::cerr);

}

void Texture::bind() {

	glBindTexture(GL_TEXTURE_2D, impl->id);

}