package com.aranea_apps.android.libs.commons;

import android.content.Context;
import android.net.wifi.WifiManager;
import android.os.Build;
import android.provider.Settings.Secure;
import android.telephony.TelephonyManager;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class UDIDGenerator {

  public static String getDeviceInfo() {
    return Build.MANUFACTURER + " " + Build.MODEL + " " + Build.VERSION.RELEASE;
  }

  public static String generateUDID(Context context) {
    //1 compute IMEI
    TelephonyManager TelephonyMgr = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
    String m_szImei = TelephonyMgr.getDeviceId(); // Requires READ_PHONE_STATE

    //2 compute DEVICE ID
    String m_szDevIDShort = "35" + //we make this look like a valid IMEI
        Build.BOARD.length() % 10 + Build.BRAND.length() % 10 +
        Build.CPU_ABI.length() % 10 + Build.DEVICE.length() % 10 +
        Build.DISPLAY.length() % 10 + Build.HOST.length() % 10 +
        Build.ID.length() % 10 + Build.MANUFACTURER.length() % 10 +
        Build.MODEL.length() % 10 + Build.PRODUCT.length() % 10 +
        Build.TAGS.length() % 10 + Build.TYPE.length() % 10 +
        Build.USER.length() % 10; //13 digits
    //3 android ID - unreliable
    String m_szAndroidID = Secure.getString(context.getContentResolver(), Secure.ANDROID_ID);

    //4 wifi manager, read MAC address - requires  android.permission.ACCESS_WIFI_STATE or comes as null
    WifiManager wm = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
    String m_szWLANMAC = wm.getConnectionInfo().getMacAddress();


    //6 SUM THE IDs
    String m_szLongID = m_szImei + m_szDevIDShort + m_szAndroidID + m_szWLANMAC;
    MessageDigest m = null;
    try {
      m = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException e) {
      e.printStackTrace();
    }
    m.update(m_szLongID.getBytes(), 0, m_szLongID.length());
    byte p_md5Data[] = m.digest();

    String m_szUniqueID = new String();
    for (int i = 0; i < p_md5Data.length; i++) {
      int b = (0xFF & p_md5Data[i]);
      // if it is a single digit, make sure it have 0 in front (proper padding)
      if (b <= 0xF) m_szUniqueID += "0";
      // add number to string
      m_szUniqueID += Integer.toHexString(b);
    }
    m_szUniqueID = m_szUniqueID.toUpperCase();
    return m_szUniqueID;
  }
}