package com.zy.nc.util;

import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

public class SHA256Util {

    public static String getSHA256(String str, String key) {
        //����
        byte[] salt = new byte[16];
        try {
            SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
            random.setSeed(key.getBytes());
            random.nextBytes(salt);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        String salt_string = Base64Util.encryptBASE64(salt);
        System.out.println("salt_String::" + salt_string);
        return getSHA256(str + salt_string.replaceAll("\r|\n", ""));
    }

    private static String getSHA256(String str) {
        MessageDigest messageDigest;
        String encodestr = "";
        try {
            messageDigest = MessageDigest.getInstance("SHA-256");
            messageDigest.update(str.getBytes(StandardCharsets.UTF_8));
            encodestr = byte2Hex(messageDigest.digest());
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
        return encodestr;
    }

    private static String byte2Hex(byte[] bytes) {
        StringBuffer stringBuffer = new StringBuffer();
        String temp = null;
        for (int i = 0; i < bytes.length; i++) {
            temp = Integer.toHexString(bytes[i] & 0xFF);
            if (temp.length() == 1) {
                // 1得到�?��的进行补0操作
                stringBuffer.append("0");
            }
            stringBuffer.append(temp);
        }
        return stringBuffer.toString();
    }

}