/**
 * Copyright 2015-2025 FLY的狐狸(email:jflyfox@sina.com qq:369191470).
 *
 * 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.
 * 
 */

package com.jflyfox.util.encrypt;

import java.security.Key;
import java.security.MessageDigest;
import java.util.Arrays;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 * DES加密
 */
public class DES3Utils {

	// 指定DES加密解密所用的密钥
	private static Key key;
	
	// 初始化向量
	private static byte[] iv = {1,2,3,4,5,6,7,8};

	/**
	 * 加密key为空
	 */
	public DES3Utils() {
		setkey("flyoffox");
	}

	/**
	 * 设置加密key
	 * 
	 * @param keyStr
	 *            加密key值
	 */
	public DES3Utils(String keyStr) {
		setkey(keyStr);
	}

	/**
	 * 设置加密的校验码
	 * 
	 * @Date:2012-10-16 下午04:25:13
	 * @ClassDescription:
	 */
	private void setkey(String keyStr) {
		try {
			final MessageDigest md = MessageDigest.getInstance("md5");
	    	final byte[] digestOfPassword = md.digest(keyStr
	    			.getBytes("utf-8"));
	    	final byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
	    	for (int j = 0, k = 16; j < 8;) {
	    		keyBytes[k++] = keyBytes[j++];
	    	}

	    	key = new SecretKeySpec(keyBytes, "DESede");

		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	// 对字符串进行DES加密，返回BASE64编码的加密字符串
	public final String encryptString(String str) {
		byte[] bytes = str.getBytes();
		try {
			Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
			//cipher.init(Cipher.ENCRYPT_MODE, key);
			IvParameterSpec zeroIv = new IvParameterSpec(iv);
			cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);
			byte[] encryptStrBytes = cipher.doFinal(bytes);
			return new String(Base64.encodeBase64(encryptStrBytes), "UTF-8");
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	// 对BASE64编码的加密字符串进行解密，返回解密后的字符串
	public final String decryptString(String str) {
		try {
			byte[] bytes = Base64.decodeBase64(str.getBytes("UTF-8"));
			Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
			
			IvParameterSpec zeroIv = new IvParameterSpec(iv);
			cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);
			bytes = cipher.doFinal(bytes);
			return new String(bytes);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}
	
	/**
	 * 测试
	 * 
	 * 2014年6月9日 下午12:37:59
	 * flyfox 330627517@qq.com
	 * @param args
	 */
	public static void main(String[] args) {
		DES3Utils des = new DES3Utils("2b7e151628aed2a6abf71589");
		String test = des.encryptString("你好123123asdasdasd阿三大声大声道，。，，。，");
		System.out.println(test);
		System.out.println(des.decryptString(test));
	}
}