package com.zzwtec.wechat.util.security;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * Created by Xin.L on 9/10/15.
 */
public class EncoderHandler {

    /** HEX_DIGITS 16进制字符 */
    private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

    public static String MD5(String input) {
        return encrypt(input, "MD5", "UTF-8");
    }

    public static String SHA1(String input) {
        return encrypt(input, "SHA-1", "UTF-8");
    }

    public static String SHA512(String input) {
        return encrypt(input, "SHA-512", "UTF-8");
    }

    // 摘要算法加密
    private static String encrypt(String input, String algorithm, String encoding) {
        MessageDigest messageDigest = null;
        byte[] bytes = null;
        try {
            messageDigest = MessageDigest.getInstance(algorithm);
            bytes = messageDigest.digest(input.getBytes(encoding));
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e);
        }
        return bytesToHex(bytes);
    }

    // bytesToHex
	private static String bytesToHex(byte[] bytes) {
		StringBuilder buff = new StringBuilder();
		for (byte bt : bytes) {
			buff.append(HEX_DIGITS[(bt & 0xf0) >> 4] + "" + HEX_DIGITS[bt & 0xf]);
		}
		return buff.toString();
	}
}