package com.ibeetl.admin.core.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.math.BigInteger;
import java.security.MessageDigest;

public class MD5Util {

    static Logger log = LoggerFactory.getLogger(MD5Util.class);
    /**
     * 字符串的MD5
     * @param plainText
     * @return
     */
    public static String encode(String plainText) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(plainText.getBytes());
            byte b[] = md.digest();

            int i;

            StringBuffer buf = new StringBuffer("");
            for (int offset = 0; offset < b.length; offset++) {
                i = b[offset];
                if (i < 0){
                    i += 256;
                }
                if (i < 16){
                    buf.append("0");
                }
                buf.append(Integer.toHexString(i));
            }
            return buf.toString();
            //System.out.println("result: " + buf.toString());// 32位的加密
            //System.out.println("result: " + buf.toString().substring(8, 24));// 16位的加密

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "";
    }

    /**
     * 文件的MD5
     * @param filePath
     * @return
     */
    public static String getFileMD5(String filePath){
        String value = null;
        FileInputStream in = null;
        try {
            File file = new File(filePath);
            in = new FileInputStream(file);
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            byte[] buffer = new byte[8192];
            int c;
            while ((c = in.read(buffer)) != -1) {
                md5.update(buffer, 0, c);
            }
            BigInteger bi = new BigInteger(1, md5.digest());
            value = bi.toString(16).toUpperCase();
        } catch (Exception e) {
            log.error("{}", e);
        } finally {
            if (null != in) {
                try {
                    in.close();
                } catch (IOException e) {
                    log.error("{}", e);
                }
            }
        }
        return value;
    }


    public static String wxPaySign(String origin, String charsetname) {
        String resultString = null;
        try {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if (charsetname == null || "".equals(charsetname)) {
                resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
            }else {
                resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
            }
        } catch (Exception exception) {
            exception.printStackTrace();
        }
        return resultString;
    }

    private static String byteArrayToHexString(byte b[]) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++)
            resultSb.append(byteToHexString(b[i]));

        return resultSb.toString();
    }

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0) {
            n += 256;
        }
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }
    private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

    public static void main(String args[]) {
        String str = "abc";
        Long b1 = System.currentTimeMillis();

        for(int i =0;i<1;i++){
            //MD5.encode(str);
            System.out.println(MD5Util.encode(str)); //900150983cd24fb0d6963f7d28e17f72

//          Md5PasswordEncoder md5 = new Md5PasswordEncoder();
//          //md5.setEncodeHashAsBase64(false);
//          //md5.encodePassword(str, "");
//          System.out.println(md5.encodePassword(str, ""));
        }
        Long e1 = System.currentTimeMillis();
        System.out.println("MD5.encode耗时:"+(e1-b1));
    }

}