<?php
/**
 *  +----------------------------------------------------------------------
 *  | CRMEB [ CRMEB赋能开发者，助力企业发展 ]
 *  +----------------------------------------------------------------------
 *  | Copyright (c) 2016~2022 https://www.crmeb.com All rights reserved.
 *  +----------------------------------------------------------------------
 *  | Licensed CRMEB并不是自由软件，未经许可不能去掉CRMEB相关版权
 *  +----------------------------------------------------------------------
 *  | Author: CRMEB Team <admin@crmeb.com>
 *  +----------------------------------------------------------------------
 */

namespace crmeb\services\wechat\util;


use InvalidArgumentException;

/**
 * AES 加密解密
 * Class AES
 * @author 等风来
 * @email 136327134@qq.com
 * @date 2023/9/18
 * @package crmeb\services\wechat\util
 */
class AES
{
    /**
     * 加密
     * @param string $text
     * @param string $key
     * @param string $iv
     * @param int $option
     *
     * @return string
     */
    public static function encrypt(string $text, string $key, string $iv, int $option = OPENSSL_RAW_DATA): string
    {
        self::validateKey($key);
        self::validateIv($iv);

        return openssl_encrypt($text, self::getMode($key), $key, $option, $iv);
    }

    /**
     * 解密
     * @param string $cipherText
     * @param string $key
     * @param string $iv
     * @param int $option
     * @param string|null $method
     *
     * @return string
     */
    public static function decrypt(string $cipherText, string $key, string $iv, int $option = OPENSSL_RAW_DATA, $method = null): string
    {
        self::validateKey($key);
        self::validateIv($iv);

        return openssl_decrypt($cipherText, $method ?: self::getMode($key), $key, $option, $iv);
    }

    /**
     * @param string $key
     *
     * @return string
     */
    public static function getMode(string $key)
    {
        return 'aes-' . (8 * strlen($key)) . '-cbc';
    }

    /**
     * @param string $key
     */
    public static function validateKey(string $key)
    {
        if (!in_array(strlen($key), [16, 24, 32], true)) {
            throw new InvalidArgumentException(sprintf('Key length must be 16, 24, or 32 bytes; got key len (%s).', strlen($key)));
        }
    }

    /**
     * @param string $iv
     *
     * @throws InvalidArgumentException
     */
    public static function validateIv(string $iv)
    {
        if (!empty($iv) && 16 !== strlen($iv)) {
            throw new InvalidArgumentException('IV length must be 16 bytes.');
        }
    }
}