package com.cirle.scientific.utils;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

/**
 * 
 * 
 * 
 * 使用强随机数生成密钥的DES加密方式
 * 
 * 
 */
public class DESUtil {
	Key key;
	private String keyString="c2n0-1h4e2a0l1t4h2c0a1r4e2.0c1o4mC!N@-#H$E%A^L|T~H`C,A;R'E.COM";
	public DESUtil() {
		setKey(keyString); // 生成密匙
	}

	public DESUtil(String str) {
		keyString = str;
		setKey(keyString); // 生成密匙
	}

	public Key getKey() {
		return key;
	}

	public void setKey(Key key) {
		this.key = key;
	}

	public void setKey(String strKey) {
		try {
			// 防止linux下 随机生成key
			SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
			secureRandom.setSeed(strKey.getBytes());
			// 为我们选择的DES算法生成一个KeyGenerator对象
			KeyGenerator kg = null;
			try {
				kg = KeyGenerator.getInstance("DES");
			} catch (NoSuchAlgorithmException e) {
				System.out.print("NoSuchAlgorithmException:"+e.getMessage());
			}
			kg.init(secureRandom);
			this.key = kg.generateKey();
			kg = null;
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		}
	}

	/**
	 * 加密 String 明文输入 ,String 密文输出
	 */
	public String encryptStr(String strMing) {
		byte[] byteMi = null;
		byte[] byteMing = null;
		String strMi = "";
		BASE64Encoder base64en = new BASE64Encoder();
		try {
			byteMing = strMing.getBytes("UTF8");
			byteMi = this.encryptByte(byteMing);
			strMi = base64en.encode(byteMi);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			base64en = null;
			byteMing = null;
			byteMi = null;
		}
		return strMi;
	}

	/**
	 * 加密 String 明文输入 ,String 密文输出
	 */
	public String encryptStrToken(String strMing) {
		byte[] byteMi = null;
		byte[] byteMing = null;
		String strMi = "";
		try {
			byteMing = strMing.getBytes("UTF8");
			byteMi = this.encryptByte(byteMing);
			strMi = Base64Util.byteArrayToBase64(byteMi);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			byteMing = null;
			byteMi = null;
		}
		return strMi;
	}
	
	
	/**
	 * 解密 以 String 密文输入 ,String 明文输出
	 * 
	 * @param strMi
	 * @return
	 */
	public String decryptStr(String strMi) {
		BASE64Decoder base64De = new BASE64Decoder();
		byte[] byteMing = null;
		byte[] byteMi = null;
		String strMing = "";
		try {
			byteMi = base64De.decodeBuffer(strMi);
			byteMing = this.decryptByte(byteMi);
			strMing = new String(byteMing, "UTF8");
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			base64De = null;
			byteMing = null;
			byteMi = null;
		}
		return strMing;
	}

	/**
	 * 加密以 byte[] 明文输入 ,byte[] 密文输出
	 * 
	 * @param byteS
	 * @return
	 */
	private byte[] encryptByte(byte[] byteS) {
		byte[] byteFina = null;
		Cipher cipher;
		try {
			cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
			cipher.init(Cipher.ENCRYPT_MODE, key);
			byteFina = cipher.doFinal(byteS);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			cipher = null;
		}
		return byteFina;
	}

	/**
	 * 解密以 byte[] 密文输入 , 以 byte[] 明文输出
	 * 
	 * @param byteD
	 * @return
	 */
	private byte[] decryptByte(byte[] byteD) {
		Cipher cipher;
		byte[] byteFina = null;
		try {
			cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
			cipher.init(Cipher.DECRYPT_MODE, key);
			byteFina = cipher.doFinal(byteD);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			cipher = null;
		}
		return byteFina;
	}

	public static void main(String[] args) throws Exception {
		DESUtil des = new DESUtil();
		// DES 加密文件
		// des.encryptFile("G:/test.doc", "G:/ 加密 test.doc");
		// DES 解密文件
		// des.decryptFile("G:/ 加密 test.doc", "G:/ 解密 test.doc");
		String str1 = "123456";
		// DES 加密字符串
		String str2 = des.encryptStr(str1);
		// DES 解密字符串
		String deStr = des.decryptStr("KaWPQANp6/A=");
		System.out.println(" 加密前： " + str1);
		System.out.println(" 加密后： " + str2);
		System.out.println(" 加密后长度： " + str2.length());
		System.out.println(" 解密后： " + deStr);
	}

	public String encode(String password) {
		byte[] byteMi = null;
		byte[] byteMing = null;
		String strMi = "";
		BASE64Encoder base64en = new BASE64Encoder();
		try {
			byteMing = password.getBytes("UTF8");
			byteMi = this.encryptByte(byteMing);
			strMi = base64en.encode(byteMi);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing SqlMap class. Cause: " + e);
		} finally {
			base64en = null;
			byteMing = null;
			byteMi = null;
		}
		return strMi;
	}
}