/**
 * OHP3D
 * 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 "Shader.h"

class Shader::Impl {
public:
	Shader::Type type;
	GLuint id;
	std::string fileName;
};

Shader::Shader(
		const Type type,
		const Buffer& source,
		const std::string& fileName) : impl(new Impl()) {
	impl->type = type;
	impl->fileName = fileName;
	impl->id = glCreateShader((GLenum) impl->type);
	update(source);
}

Shader::~Shader() {
	glDeleteShader(impl->id);
	delete impl;
}

GLuint Shader::getId() const {
	return impl->id;
}

const std::string Shader::getFileName() const {
	return impl->fileName;
}

void Shader::update(const Buffer& source) {
	auto fileData = source.getData();
	GLint fileSize = source.getSize();
	glShaderSource(impl->id, 1, &fileData, &fileSize);
	glCompileShader(impl->id);

	GLint compileStatus;
	glGetShaderiv(impl->id, GL_COMPILE_STATUS, &compileStatus);

	if (compileStatus != GL_TRUE) {
		char error[512];
		glGetShaderInfoLog(impl->id, sizeof (error), NULL, error);
		throw std::logic_error(
				std::string("GLSL: shader failed to compile: ") + error);
	}
}