package org.wxportal.util;

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

public class SignUtil {  
    private static String token;  

    public static String getToken() {
		return token;
	}

	public static void setToken(String token) {
		SignUtil.token = token;
	}

	public static boolean checkSignature(String signature, String timestamp, String nonce) {  
        String[] arr = new String[] { token, timestamp, nonce };  
        Arrays.sort(arr);  
        StringBuilder content = new StringBuilder();  
        for (int i = 0; i < arr.length; i++) {  
            content.append(arr[i]);  
        }  
        MessageDigest md = null;  
        String tmpStr = null;  
  
        try {  
            md = MessageDigest.getInstance("SHA-1");  
            byte[] digest = md.digest(content.toString().getBytes());  
            tmpStr = byteToStr(digest);  
        } catch (NoSuchAlgorithmException e) {  
            e.printStackTrace();  
        }  
  
        content = null;  
        return tmpStr != null ? tmpStr.equals(signature.toUpperCase()) : false;  
    }  

    private static String byteToStr(byte[] byteArray) {  
        String strDigest = "";  
        for (int i = 0; i < byteArray.length; i++) {  
            strDigest += byteToHexStr(byteArray[i]);  
        }  
        return strDigest;  
    }  

    private static String byteToHexStr(byte mByte) {  
        char[] Digit = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };  
        char[] tempArr = new char[2];  
        tempArr[0] = Digit[(mByte >>> 4) & 0X0F];  
        tempArr[1] = Digit[mByte & 0X0F];  
  
        String s = new String(tempArr);  
        return s;  
    }  
}  