<?php

declare(strict_types=1);

/**
 * Crypt module.
 *
 * This file is part of MadelineProto.
 * MadelineProto is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 * MadelineProto 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 Affero General Public License for more details.
 * You should have received a copy of the GNU General Public License along with MadelineProto.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * @author    Daniil Gentili <daniil@daniil.it>
 * @copyright 2016-2025 Daniil Gentili <daniil@daniil.it>
 * @license   https://opensource.org/licenses/AGPL-3.0 AGPLv3
 * @link https://docs.madelineproto.xyz MadelineProto documentation
 */

namespace danog\MadelineProto\MTProtoTools\Crypt;

use danog\MadelineProto\Magic;

/**
 * Continuous mode IGE implementation.
 *
 * @internal
 */
abstract class IGE
{
    /**
     * IV part 1.
     *
     */
    protected string $iv_part_1;
    /**
     * IV part 2.
     *
     */
    protected string $iv_part_2;
    /**
     * Instantiate appropriate handler.
     */
    public static function getInstance(string $key, string $iv): IGE
    {
        if (Magic::$hasOpenssl) {
            return new IGEOpenssl($key, $iv);
        }
        return new IGEPhpseclib($key, $iv);
    }

    abstract protected function __construct(string $key, string $iv);
    abstract public function encrypt(string $plaintext): string;
    abstract public function decrypt(string $ciphertext): string;
}