package com.mp.android.apps.utils;

import android.text.TextUtils;


import com.mp.android.apps.book.utils.FileUtil;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.HashMap;
import java.util.Map;

/**
 * MD5工具类
 */
public class MD5Utils {
    /**
     * 获取单个文件的MD5值！
     *
     * @param file
     * @return
     */

    public static String getFileMD5(File file) {
        if (!file.isFile()) {
            return null;
        }
        MessageDigest digest = null;
        FileInputStream in = null;
        byte buffer[] = new byte[1024];
        int len;
        try {
            digest = MessageDigest.getInstance("MD5");
            in = new FileInputStream(file);
            while ((len = in.read(buffer, 0, 1024)) != -1) {
                digest.update(buffer, 0, len);
            }
            in.close();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        BigInteger bigInt = new BigInteger(1, digest.digest());
        return bigInt.toString(16);
    }

    /**
     * 获取文件夹中文件的MD5值
     *
     * @param file
     * @param listChild ;true递归子目录中的文件
     * @return
     */
    public static Map<String, String> getDirMD5(File file, boolean listChild) {
        if (!file.isDirectory()) {
            return null;
        }
        Map<String, String> map = new HashMap<String, String>();
        String md5;
        File files[] = file.listFiles();
        for (int i = 0; i < files.length; i++) {
            File f = files[i];
            if (f.isDirectory() && listChild) {
                map.putAll(getDirMD5(f, listChild));
            } else {
                md5 = getFileMD5(f);
                if (md5 != null) {
                    map.put(f.getPath(), md5);
                }
            }
        }
        return map;
    }

    public static boolean checkFileMd5(String path, String md5) {
        if (FileUtil.checkFileExist(path)) {
            String hexdigest = getFileMD5(new File(path));
            assert hexdigest != null;
            return !TextUtils.isEmpty(hexdigest) && hexdigest.equals(md5);
        } else {
            return false;
        }
    }
    public static String strToMd5By32(String str){
        String reStr = null;
        try {
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            byte[] bytes = md5.digest(str.getBytes());
            StringBuffer stringBuffer = new StringBuffer();
            for (byte b : bytes){
                int bt = b&0xff;
                if (bt < 16){
                    stringBuffer.append(0);
                }
                stringBuffer.append(Integer.toHexString(bt));
            }
            reStr = stringBuffer.toString();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return reStr;
    }

    public static String strToMd5By16(String str){
        String reStr = strToMd5By32(str);
        if (reStr != null){
            reStr = reStr.substring(8, 24);
        }
        return reStr;
    }
}
