/*
 * Copyright 2020-2030 码匠君<herodotus@aliyun.com>
 *
 * Dante Engine licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Dante Engine 是 Dante Cloud 系统核心组件库，采用 APACHE LICENSE 2.0 开源协议，您在使用过程中，需要注意以下几点：
 *
 * 1. 请不要删除和修改根目录下的LICENSE文件。
 * 2. 请不要删除和修改 Dante Engine 源码头部的版权声明。
 * 3. 请保留源码和相关描述文件的项目出处，作者声明等。
 * 4. 分发源码时候，请注明软件出处 <https://gitee.com/dromara/dante-cloud>
 * 5. 在修改包名，模块名称，项目代码等时，请注明软件出处 <https://gitee.com/dromara/dante-cloud>
 * 6. 若您的项目无法满足以上几点，可申请商业授权
 */

package org.dromara.dante.web.autoconfigure.envelope;

import cn.hutool.v7.core.codec.binary.HexUtil;
import cn.hutool.v7.crypto.bc.SmUtil;
import cn.hutool.v7.crypto.symmetric.SM4;
import org.dromara.dante.web.support.crypto.SymmetricCryptoProcessor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.crypto.SecretKey;

/**
 * <p>Description: 国密对称算法 SM4 处理器 </p>
 *
 * @author : gengwei.zheng
 * @date : 2022/5/2 16:56
 */
class SM4CryptoProcessor implements SymmetricCryptoProcessor {

    private static final Logger log = LoggerFactory.getLogger(SM4CryptoProcessor.class);

    @Override
    public String createKey() {
        SM4 sm4 = SmUtil.sm4();
        SecretKey secretKey = sm4.getSecretKey();
        byte[] encoded = secretKey.getEncoded();
        String result = HexUtil.encodeStr(encoded);
        log.trace("[Herodotus] |- SM4 crypto create hex key, value is : [{}]", result);
        return result;
    }

    @Override
    public String decrypt(String data, String key) {
        // TODO: 2022-05-08 这里主要有一个诡异问题：大多数情况都没有问题，但是相关代码已放到 DecryptRequestBodyAdvice 里面就无法解密
        SM4 sm4 = SmUtil.sm4(HexUtil.decode(key));
        log.trace("[Herodotus] |- SM4 crypto decrypt data [{}] with key : [{}]", data, key);
        String result = sm4.decryptStr(data);
        log.trace("[Herodotus] |- SM4 crypto decrypt result is : [{}]", result);
        return result;
    }

    @Override
    public String encrypt(String data, String key) {
        SM4 sm4 = SmUtil.sm4(HexUtil.decode(key));
        log.trace("[Herodotus] |- SM4 crypto encrypt data [{}] with key : [{}]", data, key);
        String result = sm4.encryptHex(data);
        log.trace("[Herodotus] |- SM4 crypto encrypt result is : [{}]", result);
        return result;
    }
}
