package com.winsun.smsUtils;

import lombok.extern.slf4j.Slf4j;

/**
 * XXTea加解密实�?
 */
@Slf4j
public class XXTea {

	/**
	 * 加密
	 * @param plain 明文
	 * @param charset 明文字符编码
	 * @param hexKey 十六进制字符串形式密�?
	 * @return 十六进制字符串形式密�?
	 * @throws Exception
	 */
	public static
	String encrypt(String plain, String charset, String hexKey) 
			throws Exception {
		if (plain == null || charset == null || hexKey == null) {
				return null;
		}
		
		return ByteFormat.toHex(
					encrypt(plain.getBytes(charset), ByteFormat.hexToBytes(hexKey)));
	}
	
	/**
	 * 解密
	 * @param cipherHex 十六进制字符串形式密�?
	 * @param charset 明文字符编码
	 * @param hexKey 十六进制字符串形式密�?
	 * @return 明文
	 * @throws Exception
	 */
	public static
	String decrypt(String cipherHex, String charset, String hexKey) throws Exception{
		if (cipherHex == null || charset == null || hexKey == null) {
			return null;
		}
		return new String(
				decrypt(ByteFormat.hexToBytes(cipherHex), ByteFormat.hexToBytes(hexKey)),
				charset);
	
	}
	
	/**
	 * 加密
	 * @param plainData 明文
	 * @param key 密钥
	 * @return
	 */
	public static
	byte[] encrypt(byte[] plainData, byte[] key) {
		if (plainData == null || plainData.length == 0 || key == null) {
			return null;
		}
		return toByteArray(
					encrypt(toIntArray(plainData, true), toIntArray(key, false)),
					false);
	}

	/**
	 * 解密
	 * @param cipherData 密文
	 * @param key 密钥
	 * @return 明文
	 */
	public static
	byte[] decrypt(byte[] cipherData, byte[] key) {
		if (cipherData == null || cipherData.length == 0 || key == null) {
			return null;
		}
		return toByteArray(
					decrypt(toIntArray(cipherData, false), toIntArray(key, false)),
					true);
	}

	/**
	 * Encrypt data with key.
	 * 
	 * @param v
	 * @param k
	 * @return
	 */
	private static
	int[] encrypt(int[] v, int[] k) {
		int n = v.length - 1;

		if (n < 1) {
			return v;
		}
		if (k.length < 4) {
			int[] key = new int[4];

			System.arraycopy(k, 0, key, 0, k.length);
			k = key;
		}
		int z = v[n], y = v[0], delta = 0x9E3779B9, sum = 0, e;
		int p, q = 6 + 52 / (n + 1);

		while (q-- > 0) {
			sum = sum + delta;
			e = sum >>> 2 & 3;
			for (p = 0; p < n; p++) {
				y = v[p + 1];
				z = v[p] += (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y)
						+ (k[p & 3 ^ e] ^ z);
			}
			y = v[0];
			z = v[n] += (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y)
					+ (k[p & 3 ^ e] ^ z);
		}
		return v;
	}

	/**
	 * Decrypt data with key.
	 * 
	 * @param v
	 * @param k
	 * @return
	 */
	private static
	int[] decrypt(int[] v, int[] k) {
		int n = v.length - 1;

		if (n < 1) {
			return v;
		}
		if (k.length < 4) {
			int[] key = new int[4];

			System.arraycopy(k, 0, key, 0, k.length);
			k = key;
		}
		int z = v[n], y = v[0], delta = 0x9E3779B9, sum, e;
		int p, q = 6 + 52 / (n + 1);

		sum = q * delta;
		while (sum != 0) {
			e = sum >>> 2 & 3;
			for (p = n; p > 0; p--) {
				z = v[p - 1];
				y = v[p] -= (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y)
						+ (k[p & 3 ^ e] ^ z);
			}
			z = v[n];
			y = v[0] -= (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y)
					+ (k[p & 3 ^ e] ^ z);
			sum = sum - delta;
		}
		return v;
	}

	/**
	 * Convert byte array to int array.
	 * 
	 * @param data
	 * @param includeLength
	 * @return
	 */
	private static
	int[] toIntArray(byte[] data, boolean includeLength) {
		int n = (((data.length & 3) == 0) ? (data.length >>> 2)
				: ((data.length >>> 2) + 1));
		int[] result;

		if (includeLength) {
			result = new int[n + 1];
			result[n] = data.length;
		} else {
			result = new int[n];
		}
		n = data.length;
		for (int i = 0; i < n; i++) {
			result[i >>> 2] |= (0x000000ff & data[i]) << ((i & 3) << 3);
		}
		return result;
	}

	/**
	 * Convert int array to byte array.
	 * 
	 * @param data
	 * @param includeLength
	 * @return
	 */
	private static
	byte[] toByteArray(int[] data, boolean includeLength) {
		int n = data.length << 2;
		if (includeLength) {
			int m = data[data.length - 1];

			if (m > n || m <= 0) {
				return null;
			} else {
				n = m;
			}
		}
		byte[] result = new byte[n];

		for (int i = 0; i < n; i++) {
			result[i] = (byte) ((data[i >>> 2] >>> ((i & 3) << 3)) & 0xff);
		}
		return result;
	}

	public static void main(String args[]){
		String plainText = "dffrrereeeeeeeeeeeeeeeeeeeeeeeerererefffrererefffddfdfdfdfdfdfdf343434343434343ffffrerererere;l;l;ll;;l;l;lffffffffff4343434343434343434343ffffffffffffffffffffffffabcdefgddddddddddddddddddddsdssddssdsdsssddsddddddddddddsdsjj111gfgfgfffffff;llklklklklkkhghghghghgkkkkkkkkkkkkkkkkkkhghjffffffffffffffgao";
		byte key[] = "GdWb5dnxhUxFKcE4GqdhL23TndZFYXPy".getBytes();
		try{
			 long t1 = System.currentTimeMillis();
			String cipherText = 
			XXTea.encrypt(plainText,"UTF-8",ByteFormat.toHex(key));
			log.info(cipherText);
			
			String pText = XXTea.decrypt(cipherText,"UTF-8",ByteFormat.toHex(key));
			log.info(pText);
			long t2 = System.currentTimeMillis();
			log.info((t2-t1) + "");
		}catch(Exception ex){
			ex.printStackTrace();
		}

	}

}
