package com.mm.util;

import org.bouncycastle.crypto.digests.SM3Digest;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.pqc.math.linearalgebra.ByteUtils;

import java.io.UnsupportedEncodingException;
import java.security.Security;
import java.util.Arrays;

/**
 * @author clown
 * * @date 2023/11/23
 */
public class SM3Util {
    /**
     * 编码格式
     */
    private static final String ENCODING = "UTF-8";

    static{
        Security.addProvider(new BouncyCastleProvider());
    }

    /**
     *
     * @param paramStr 要sm3加密的内容
     * @return sm3加密后密文
     */
    public static String encrypt(String paramStr){
        String resultHexString = "";
        try {
            byte[] srcData = paramStr.getBytes(ENCODING);
            byte[] hash = hash(srcData);
            resultHexString = ByteUtils.toHexString(hash);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return resultHexString;
    }

    public static byte[] hash(byte[] srcData){
        SM3Digest sm3Digest = new SM3Digest();
        sm3Digest.update(srcData,0,srcData.length);
        byte[] bytes = new byte[sm3Digest.getDigestSize()];
        sm3Digest.doFinal(bytes,0);
        return bytes;
    }

    /**
     *
     * @param str 明文
     * @param hexString 密文
     * @return 明文密文对比结果
     */
    public static boolean verify(String str,String hexString){
        boolean flag = false;
        try {
            byte[] srcData = str.getBytes(ENCODING);
            byte[] sm3Hash = ByteUtils.fromHexString(hexString);
            byte[] hash = hash(srcData);
            if (Arrays.equals(hash,sm3Hash)){
                flag = true;
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return flag;
    }

}