package com.ppdai.infrastructure.ui.utils;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import java.security.SecureRandom;
import java.util.UUID;

/** 
 * Copyright 2007 GuangZhou Cotel Co. Ltd. 
 * All right reserved.     
 * DES加密解密类.      
 * @author <a href="mailto:[email protected]" mce_href="mailto:[email protected]">AmigoXie</a> 
 * @version 1.0  
 * Creation date: 2007-7-31 - 上午11:59:28 
 */  
public class DesUtil {  
    /** 加密、解密key. */  
    private static final String PASSWORD_CRYPT_KEY = "kEHrDooxWHCWtfeSxvDvgqZq";  
    /** 加密<a href="http://lib.csdn.net/base/datastructure" class='replace_word' title="算法与数据结构知识库" target='_blank' style='color:#df3434; font-weight:bold;'>算法</a>,可用 DES,DESede,Blowfish. */  
    private final static String ALGORITHM = "DES";     
      
    /** 
     * 对数据进行DES加密. 
     * @param data 待进行DES加密的数据 
     * @return 返回经过DES加密后的数据 
     * @throws Exception 
     * @author <a href="mailto:[email protected]" mce_href="mailto:[email protected]">AmigoXie</a> 
     * Creation date: 2007-7-31 - 下午12:06:24 
     */  
    public final static String decrypt(String data) throws Exception {  
        return new String(decrypt(hex2byte(data.getBytes()),  
                PASSWORD_CRYPT_KEY.getBytes()));  
    }  
    /** 
     * 对用DES加密过的数据进行解密. 
     * @param data DES加密数据 
     * @return 返回解密后的数据 
     * @throws Exception 
     * @author <a href="mailto:[email protected]" mce_href="mailto:[email protected]">AmigoXie</a> 
     * Creation date: 2007-7-31 - 下午12:07:54 
     */  
    public final static String encrypt(String data) throws Exception  {  
        return byte2hex(encrypt(data.getBytes(), PASSWORD_CRYPT_KEY  
                .getBytes()));  
    }  
      
    /** 
     * 用指定的key对数据进行DES加密. 
     * @param data 待加密的数据 
     * @param key DES加密的key 
     * @return 返回DES加密后的数据 
     * @throws Exception 
     * @author <a href="mailto:[email protected]" mce_href="mailto:[email protected]">AmigoXie</a> 
     * Creation date: 2007-7-31 - 下午12:09:03 
     */  
    private static byte[] encrypt(byte[] data, byte[] 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);  
        // 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(ALGORITHM);  
        SecretKey securekey = keyFactory.generateSecret(dks);  
        // Cipher对象实际完成加密操作  
        Cipher cipher = Cipher.getInstance(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  
        return cipher.doFinal(data);  
    }  
    /** 
     * 用指定的key对数据进行DES解密. 
     * @param data 待解密的数据 
     * @param key DES解密的key 
     * @return 返回DES解密后的数据 
     * @throws Exception 
     * @author <a href="mailto:[email protected]" mce_href="mailto:[email protected]">AmigoXie</a> 
     * Creation date: 2007-7-31 - 下午12:10:34 
     */  
    private static byte[] decrypt(byte[] data, byte[] 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);  
        // 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(ALGORITHM);  
        SecretKey securekey = keyFactory.generateSecret(dks);  
        // Cipher对象实际完成解密操作  
        Cipher cipher = Cipher.getInstance(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 cipher.doFinal(data);  
    }  
    public static byte[] hex2byte(byte[] b) {  
        if ((b.length % 2) != 0)  
            throw new IllegalArgumentException("长度不是偶数");  
        byte[] b2 = new byte[b.length / 2];  
        for (int n = 0; n < b.length; n += 2) {  
            String item = new String(b, n, 2);  
            b2[n / 2] = (byte) Integer.parseInt(item, 16);  
        }  
        return b2;  
    }  
    public static String byte2hex(byte[] b) {  
        String hs = "";  
        String stmp = "";  
        for (int n = 0; n < b.length; n++) {  
            stmp = (Integer.toHexString(b[n] & 0XFF));
            if (stmp.length() == 1)  
                hs = hs + "0" + stmp;  
            else  
                hs = hs + stmp;  
        }  
        return hs.toUpperCase();  
    }

    public static String getUuidToken()
    {
        return UUID.randomUUID().toString().replace("-", "");
    }
}