package com.hxzk.util;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;

public class DESUtil {
    //算法名称 
    public static final String KEY_ALGORITHM = "DES";
    //算法名称/加密模式/填充方式 
    //DES共有四种工作模式-->>ECB：电子密码本模式、CBC：加密分组链接模式、CFB：加密反馈模式、OFB：输出反馈模式
    public static final String CIPHER_ALGORITHM = "DESede/CBC/PKCS5Padding";
    
   public static String key = "FHGT4KHVJKVKV2KHCTBM";
    /**
     * 生成密钥key对象
     * @param KeyStr 密钥字符串 
     * @return 密钥对象 
     * @throws InvalidKeyException   
     * @throws NoSuchAlgorithmException   
     * @throws InvalidKeySpecException   
     * @throws Exception 
     */
    private static SecretKey keyGenerator(String keyStr) throws Exception {
        byte input[] = HexString2Bytes(keyStr);
        DESKeySpec desKey = new DESKeySpec(input);
        //创建一个密匙工厂，然后用它把DESKeySpec转换成
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        SecretKey securekey = keyFactory.generateSecret(desKey);
        return securekey;
    }

    private static int parse(char c) {
        if (c >= 'a') return (c - 'a' + 10) & 0x0f;
        if (c >= 'A') return (c - 'A' + 10) & 0x0f;
        return (c - '0') & 0x0f;
    }

    // 从十六进制字符串到字节数组转换 
    public static byte[] HexString2Bytes(String hexstr) {
        byte[] b = new byte[hexstr.length() / 2];
        int j = 0;
        for (int i = 0; i < b.length; i++) {
            char c0 = hexstr.charAt(j++);
            char c1 = hexstr.charAt(j++);
            b[i] = (byte) ((parse(c0) << 4) | parse(c1));
        }
        return b;
    }

    /** 
     * 加密数据
     * @param data 待加密数据
     * @param key 密钥
     * @return 加密后的数据 
     */
    public static String encrypt(String data, String key) throws Exception {
      //DES算法要求有一个可信任的随机数源
        SecureRandom sr = new SecureRandom();
        // 从原始密匙数据创建DESKeySpec对象
        DESKeySpec dks = new DESKeySpec(key.getBytes());
        // 创建一个密匙工厂，然后用它把DESKeySpec转换成
        // 一个SecretKey对象
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(KEY_ALGORITHM);
        SecretKey securekey = keyFactory.generateSecret(dks);
        // Cipher对象实际完成加密操作
        Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
        // 用密匙初始化Cipher对象
        cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
        // 现在，获取数据并加密
        // 正式执行加密操作
        byte[] results= cipher.doFinal(data.getBytes());
        return Base64.encodeBase64String(results);
    }

    /** 
     * 解密数据 
     * @param data 待解密数据 
     * @param key 密钥 
     * @return 解密后的数据 
     */
    public static String decrypt(String data, String key) throws Exception {
        
        // DES算法要求有一个可信任的随机数源
        SecureRandom sr = new SecureRandom();
        // 从原始密匙数据创建一个DESKeySpec对象
        DESKeySpec dks = new DESKeySpec(key.getBytes());
        // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成
        // 一个SecretKey对象
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(KEY_ALGORITHM);
        SecretKey securekey = keyFactory.generateSecret(dks);
        // Cipher对象实际完成解密操作
        Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
        // 用密匙初始化Cipher对象
        cipher.init(Cipher.DECRYPT_MODE, securekey, sr);
        // 现在，获取数据并解密
        // 正式执行解密操作
        return new String(cipher.doFinal(Base64.decodeBase64(data)));
    }

    public static void main(String[] args) throws Exception {
//        String url = "jdbc:mysql://127.0.0.1:3306/hxzkoa?useUnicode=true&characterEncoding=UTF-8&useSSL=false&autoReconnect=true";
//        String username = "hxzkoa";
//        String password = "XXX";
//        System.out.println("url: " + url);
//        System.out.println("username: " + username);
//        System.out.println("password: " + password);
//        String e_url = encrypt(url, key);
//        String e_username = encrypt(username, key);
//        String e_password = encrypt(password, key);
//        System.out.println("加密后url: " + e_url);
//        System.out.println("加密后username: " + e_username);
//        System.out.println("加密后password: " + e_password);
    	
        String url = "jdbc:mysql://localhost:3306/hxzkuwb?useUnicode=true&characterEncoding=UTF-8&useSSL=false&autoReconnect=true";
        String username = "root";
        String password = "123456";
        System.out.println("url: " + url);
        System.out.println("username: " + username);
        System.out.println("password: " + password);
        String e_url = encrypt(url, key);
        String e_username = encrypt(username, key);
        String e_password = encrypt(password,key);
        System.out.println("加密后url: " + e_url);
        System.out.println("加密后username: " + e_username);
        System.out.println("加密后password: " + e_password);
    }
}