/*
 * 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.contacts.common.location;

import android.app.IntentService;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.preference.PreferenceManager;
import android.util.Log;
import java.io.IOException;
import java.util.List;

/**
 * Service used to perform asynchronous geocoding from within a broadcast receiver. Given a {@link
 * Location}, convert it into a country code, and save it in shared preferences.
 */
public class UpdateCountryService extends IntentService {

  private static final String TAG = UpdateCountryService.class.getSimpleName();

  private static final String ACTION_UPDATE_COUNTRY = "saveCountry";

  private static final String KEY_INTENT_LOCATION = "location";

  public UpdateCountryService() {
    super(TAG);
  }

  public static void updateCountry(Context context, Location location) {
    final Intent serviceIntent = new Intent(context, UpdateCountryService.class);
    serviceIntent.setAction(ACTION_UPDATE_COUNTRY);
    serviceIntent.putExtra(UpdateCountryService.KEY_INTENT_LOCATION, location);
    context.startService(serviceIntent);
  }

  @Override
  protected void onHandleIntent(Intent intent) {
    if (intent == null) {
      Log.d(TAG, "onHandleIntent: could not handle null intent");
      return;
    }
    if (ACTION_UPDATE_COUNTRY.equals(intent.getAction())) {
      final Location location = intent.getParcelableExtra(KEY_INTENT_LOCATION);
      final String country = getCountryFromLocation(getApplicationContext(), location);

      if (country == null) {
        return;
      }

      final SharedPreferences prefs =
          PreferenceManager.getDefaultSharedPreferences(getApplicationContext());

      final Editor editor = prefs.edit();
      editor.putLong(CountryDetector.KEY_PREFERENCE_TIME_UPDATED, System.currentTimeMillis());
      editor.putString(CountryDetector.KEY_PREFERENCE_CURRENT_COUNTRY, country);
      editor.commit();
    }
  }

  /**
   * Given a {@link Location}, return a country code.
   *
   * @return the ISO 3166-1 two letter country code
   */
  private String getCountryFromLocation(Context context, Location location) {
    final Geocoder geocoder = new Geocoder(context);
    String country = null;
    try {
      double latitude = location.getLatitude();
      // Latitude has to be between 90 and -90 (latitude of north and south poles wrt equator)
      if (latitude <= 90 && latitude >= -90) {
        final List<Address> addresses =
            geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
        if (addresses != null && addresses.size() > 0) {
          country = addresses.get(0).getCountryCode();
        }
      } else {
        Log.w(TAG, "Invalid latitude");
      }
    } catch (IOException e) {
      Log.w(TAG, "Exception occurred when getting geocoded country from location");
    }
    return country;
  }
}