/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.dialer.common;

import android.content.Context;
import android.content.pm.PackageManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.support.annotation.Nullable;
import android.support.annotation.RequiresPermission;
import android.support.annotation.StringDef;
import android.telephony.TelephonyManager;
import android.text.TextUtils;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Objects;

/** Utility class for dealing with network */
public class NetworkUtil {

  /* Returns the current network type. */
  @RequiresPermission("android.permission.ACCESS_NETWORK_STATE")
  @NetworkType
  public static String getCurrentNetworkType(@Nullable Context context) {
    if (context == null) {
      return NetworkType.NONE;
    }
    ConnectivityManager connectivityManager =
        (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    return getNetworkType(connectivityManager.getActiveNetworkInfo());
  }

  /* Returns the current network info. */
  @Nullable
  @RequiresPermission("android.permission.ACCESS_NETWORK_STATE")
  public static NetworkInfo getCurrentNetworkInfo(@Nullable Context context) {
    if (context == null) {
      return null;
    }
    ConnectivityManager connectivityManager =
        (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    return connectivityManager.getActiveNetworkInfo();
  }

  /**
   * Returns the current network type as a string. For mobile network types the subtype name of the
   * network is appended.
   */
  @RequiresPermission("android.permission.ACCESS_NETWORK_STATE")
  public static String getCurrentNetworkTypeName(@Nullable Context context) {
    if (context == null) {
      return NetworkType.NONE;
    }
    ConnectivityManager connectivityManager =
        (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo netInfo = connectivityManager.getActiveNetworkInfo();
    @NetworkType String networkType = getNetworkType(netInfo);
    if (isNetworkTypeMobile(networkType)) {
      return networkType + " (" + netInfo.getSubtypeName() + ")";
    }
    return networkType;
  }

  @NetworkType
  public static String getNetworkType(@Nullable NetworkInfo netInfo) {
    if (netInfo == null || !netInfo.isConnected()) {
      return NetworkType.NONE;
    }
    switch (netInfo.getType()) {
      case ConnectivityManager.TYPE_WIFI:
        return NetworkType.WIFI;
      case ConnectivityManager.TYPE_MOBILE:
        return getMobileNetworkType(netInfo.getSubtype());
      default:
        return NetworkType.UNKNOWN;
    }
  }

  public static boolean isNetworkTypeMobile(@NetworkType String networkType) {
    return Objects.equals(networkType, NetworkType.MOBILE_2G)
        || Objects.equals(networkType, NetworkType.MOBILE_3G)
        || Objects.equals(networkType, NetworkType.MOBILE_4G);
  }

  @RequiresPermission("android.permission.ACCESS_NETWORK_STATE")
  public static String getCurrentNetworkName(Context context) {
    @NetworkType String networkType = getCurrentNetworkType(context);
    switch (networkType) {
      case NetworkType.WIFI:
        return getWifiNetworkName(context);
      case NetworkType.MOBILE_2G:
      case NetworkType.MOBILE_3G:
      case NetworkType.MOBILE_4G:
      case NetworkType.MOBILE_UNKNOWN:
        return getMobileNetworkName(context);
      default:
        return "";
    }
  }

  private static String getWifiNetworkName(Context context) {
    WifiManager wifiMgr = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
    String name = null;
    if (context.checkSelfPermission("android.permission.ACCESS_WIFI_STATE")
        == PackageManager.PERMISSION_GRANTED) {
      //noinspection MissingPermission
      WifiInfo wifiInfo = wifiMgr.getConnectionInfo();
      if (wifiInfo == null) {
        return "";
      }
      name = wifiInfo.getSSID();
    }
    return TextUtils.isEmpty(name)
        ? context.getString(R.string.network_name_wifi)
        : name.replaceAll("\"", "");
  }

  private static String getMobileNetworkName(Context context) {
    TelephonyManager telephonyMgr =
        (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
    String name = telephonyMgr.getNetworkOperatorName();
    return TextUtils.isEmpty(name)
        ? context.getString(R.string.network_name_mobile)
        : name.replaceAll("\"", "");
  }

  @NetworkType
  private static String getMobileNetworkType(int networkSubtype) {
    switch (networkSubtype) {
      case TelephonyManager.NETWORK_TYPE_1xRTT:
      case TelephonyManager.NETWORK_TYPE_CDMA:
      case TelephonyManager.NETWORK_TYPE_EDGE:
      case TelephonyManager.NETWORK_TYPE_GPRS:
      case TelephonyManager.NETWORK_TYPE_IDEN:
        return NetworkType.MOBILE_2G;
      case TelephonyManager.NETWORK_TYPE_EHRPD:
      case TelephonyManager.NETWORK_TYPE_EVDO_0:
      case TelephonyManager.NETWORK_TYPE_EVDO_A:
      case TelephonyManager.NETWORK_TYPE_EVDO_B:
      case TelephonyManager.NETWORK_TYPE_HSDPA:
      case TelephonyManager.NETWORK_TYPE_HSPA:
      case TelephonyManager.NETWORK_TYPE_HSPAP:
      case TelephonyManager.NETWORK_TYPE_HSUPA:
      case TelephonyManager.NETWORK_TYPE_UMTS:
        return NetworkType.MOBILE_3G;
      case TelephonyManager.NETWORK_TYPE_LTE:
        return NetworkType.MOBILE_4G;
      default:
        return NetworkType.MOBILE_UNKNOWN;
    }
  }

  /** Network types. */
  @Retention(RetentionPolicy.SOURCE)
  @StringDef(
    value = {
      NetworkType.NONE,
      NetworkType.WIFI,
      NetworkType.MOBILE_2G,
      NetworkType.MOBILE_3G,
      NetworkType.MOBILE_4G,
      NetworkType.MOBILE_UNKNOWN,
      NetworkType.UNKNOWN
    }
  )
  public @interface NetworkType {

    String NONE = "NONE";
    String WIFI = "WIFI";
    String MOBILE_2G = "MOBILE_2G";
    String MOBILE_3G = "MOBILE_3G";
    String MOBILE_4G = "MOBILE_4G";
    String MOBILE_UNKNOWN = "MOBILE_UNKNOWN";
    String UNKNOWN = "UNKNOWN";
  }
}