| /* |
| * Copyright 2019 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.internal.telephony.nitz; |
| |
| import static android.app.timezonedetector.TelephonyTimeZoneSuggestion.createEmptySuggestion; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.app.timezonedetector.TelephonyTimeZoneSuggestion; |
| import android.os.TimestampedValue; |
| import android.text.TextUtils; |
| import android.timezone.CountryTimeZones.OffsetResult; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.telephony.NitzData; |
| import com.android.internal.telephony.NitzStateMachine.DeviceState; |
| import com.android.internal.telephony.nitz.NitzStateMachineImpl.TimeZoneSuggester; |
| import com.android.internal.telephony.nitz.TimeZoneLookupHelper.CountryResult; |
| import com.android.telephony.Rlog; |
| |
| import java.util.Objects; |
| |
| /** |
| * The real implementation of {@link TimeZoneSuggester}. |
| */ |
| @VisibleForTesting |
| public class TimeZoneSuggesterImpl implements TimeZoneSuggester { |
| |
| private static final String LOG_TAG = NitzStateMachineImpl.LOG_TAG; |
| |
| private final DeviceState mDeviceState; |
| private final TimeZoneLookupHelper mTimeZoneLookupHelper; |
| |
| @VisibleForTesting |
| public TimeZoneSuggesterImpl( |
| @NonNull DeviceState deviceState, @NonNull TimeZoneLookupHelper timeZoneLookupHelper) { |
| mDeviceState = Objects.requireNonNull(deviceState); |
| mTimeZoneLookupHelper = Objects.requireNonNull(timeZoneLookupHelper); |
| } |
| |
| @Override |
| @NonNull |
| public TelephonyTimeZoneSuggestion getTimeZoneSuggestion(int slotIndex, |
| @Nullable String countryIsoCode, @Nullable TimestampedValue<NitzData> nitzSignal) { |
| try { |
| // Check for overriding NITZ-based signals from Android running in an emulator. |
| TelephonyTimeZoneSuggestion overridingSuggestion = null; |
| if (nitzSignal != null) { |
| NitzData nitzData = nitzSignal.getValue(); |
| if (nitzData.getEmulatorHostTimeZone() != null) { |
| TelephonyTimeZoneSuggestion.Builder builder = |
| new TelephonyTimeZoneSuggestion.Builder(slotIndex) |
| .setZoneId(nitzData.getEmulatorHostTimeZone().getID()) |
| .setMatchType(TelephonyTimeZoneSuggestion.MATCH_TYPE_EMULATOR_ZONE_ID) |
| .setQuality(TelephonyTimeZoneSuggestion.QUALITY_SINGLE_ZONE) |
| .addDebugInfo("Emulator time zone override: " + nitzData); |
| overridingSuggestion = builder.build(); |
| } |
| } |
| |
| TelephonyTimeZoneSuggestion suggestion; |
| if (overridingSuggestion != null) { |
| suggestion = overridingSuggestion; |
| } else if (countryIsoCode == null) { |
| if (nitzSignal == null) { |
| suggestion = createEmptySuggestion(slotIndex, |
| "getTimeZoneSuggestion: nitzSignal=null, countryIsoCode=null"); |
| } else { |
| // NITZ only - wait until we have a country. |
| suggestion = createEmptySuggestion(slotIndex, "getTimeZoneSuggestion:" |
| + " nitzSignal=" + nitzSignal + ", countryIsoCode=null"); |
| } |
| } else { // countryIsoCode != null |
| if (nitzSignal == null) { |
| if (countryIsoCode.isEmpty()) { |
| // This is assumed to be a test network with no NITZ data to go on. |
| suggestion = createEmptySuggestion(slotIndex, |
| "getTimeZoneSuggestion: nitzSignal=null, countryIsoCode=\"\""); |
| } else { |
| // Country only |
| suggestion = findTimeZoneFromNetworkCountryCode( |
| slotIndex, countryIsoCode, mDeviceState.currentTimeMillis()); |
| } |
| } else { // nitzSignal != null |
| if (countryIsoCode.isEmpty()) { |
| // We have been told we have a country code but it's empty. This is most |
| // likely because we're on a test network that's using a bogus MCC |
| // (eg, "001"). Obtain a TimeZone based only on the NITZ parameters: without |
| // a country it will be arbitrary, but it should at least have the correct |
| // offset. |
| suggestion = findTimeZoneForTestNetwork(slotIndex, nitzSignal); |
| } else { |
| // We have both NITZ and Country code. |
| suggestion = findTimeZoneFromCountryAndNitz( |
| slotIndex, countryIsoCode, nitzSignal); |
| } |
| } |
| } |
| |
| // Ensure the return value is never null. |
| Objects.requireNonNull(suggestion); |
| |
| return suggestion; |
| } catch (RuntimeException e) { |
| // This would suggest a coding error. Log at a high level and try to avoid leaving the |
| // device in a bad state by making an "empty" suggestion. |
| String message = "getTimeZoneSuggestion: Error during lookup: " |
| + " countryIsoCode=" + countryIsoCode |
| + ", nitzSignal=" + nitzSignal |
| + ", e=" + e.getMessage(); |
| TelephonyTimeZoneSuggestion errorSuggestion = createEmptySuggestion(slotIndex, message); |
| Rlog.w(LOG_TAG, message, e); |
| return errorSuggestion; |
| } |
| } |
| |
| /** |
| * Creates a {@link TelephonyTimeZoneSuggestion} using only NITZ. This happens when the device |
| * is attached to a test cell with an unrecognized MCC. In these cases we try to return a |
| * suggestion for an arbitrary time zone that matches the NITZ offset information. |
| */ |
| @NonNull |
| private TelephonyTimeZoneSuggestion findTimeZoneForTestNetwork( |
| int slotIndex, @NonNull TimestampedValue<NitzData> nitzSignal) { |
| Objects.requireNonNull(nitzSignal); |
| NitzData nitzData = Objects.requireNonNull(nitzSignal.getValue()); |
| |
| TelephonyTimeZoneSuggestion.Builder suggestionBuilder = |
| new TelephonyTimeZoneSuggestion.Builder(slotIndex); |
| suggestionBuilder.addDebugInfo("findTimeZoneForTestNetwork: nitzSignal=" + nitzSignal); |
| OffsetResult lookupResult = |
| mTimeZoneLookupHelper.lookupByNitz(nitzData); |
| if (lookupResult == null) { |
| suggestionBuilder.addDebugInfo("findTimeZoneForTestNetwork: No zone found"); |
| } else { |
| suggestionBuilder.setZoneId(lookupResult.getTimeZone().getID()); |
| suggestionBuilder.setMatchType( |
| TelephonyTimeZoneSuggestion.MATCH_TYPE_TEST_NETWORK_OFFSET_ONLY); |
| int quality = lookupResult.isOnlyMatch() |
| ? TelephonyTimeZoneSuggestion.QUALITY_SINGLE_ZONE |
| : TelephonyTimeZoneSuggestion.QUALITY_MULTIPLE_ZONES_WITH_SAME_OFFSET; |
| suggestionBuilder.setQuality(quality); |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneForTestNetwork: lookupResult=" + lookupResult); |
| } |
| return suggestionBuilder.build(); |
| } |
| |
| /** |
| * Creates a {@link TelephonyTimeZoneSuggestion} using network country code and NITZ. |
| */ |
| @NonNull |
| private TelephonyTimeZoneSuggestion findTimeZoneFromCountryAndNitz( |
| int slotIndex, @NonNull String countryIsoCode, |
| @NonNull TimestampedValue<NitzData> nitzSignal) { |
| Objects.requireNonNull(countryIsoCode); |
| Objects.requireNonNull(nitzSignal); |
| |
| TelephonyTimeZoneSuggestion.Builder suggestionBuilder = |
| new TelephonyTimeZoneSuggestion.Builder(slotIndex); |
| suggestionBuilder.addDebugInfo("findTimeZoneFromCountryAndNitz:" |
| + " countryIsoCode=" + countryIsoCode |
| + ", nitzSignal=" + nitzSignal); |
| NitzData nitzData = Objects.requireNonNull(nitzSignal.getValue()); |
| if (isNitzSignalOffsetInfoBogus(countryIsoCode, nitzData)) { |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneFromCountryAndNitz: NITZ signal looks bogus"); |
| return suggestionBuilder.build(); |
| } |
| |
| // Try to find a match using both country + NITZ signal. |
| OffsetResult lookupResult = |
| mTimeZoneLookupHelper.lookupByNitzCountry(nitzData, countryIsoCode); |
| if (lookupResult != null) { |
| suggestionBuilder.setZoneId(lookupResult.getTimeZone().getID()); |
| suggestionBuilder.setMatchType( |
| TelephonyTimeZoneSuggestion.MATCH_TYPE_NETWORK_COUNTRY_AND_OFFSET); |
| int quality = lookupResult.isOnlyMatch() |
| ? TelephonyTimeZoneSuggestion.QUALITY_SINGLE_ZONE |
| : TelephonyTimeZoneSuggestion.QUALITY_MULTIPLE_ZONES_WITH_SAME_OFFSET; |
| suggestionBuilder.setQuality(quality); |
| suggestionBuilder.addDebugInfo("findTimeZoneFromCountryAndNitz:" |
| + " lookupResult=" + lookupResult); |
| return suggestionBuilder.build(); |
| } |
| |
| // The country + offset provided no match, so see if the country by itself would be enough. |
| CountryResult countryResult = mTimeZoneLookupHelper.lookupByCountry( |
| countryIsoCode, nitzData.getCurrentTimeInMillis()); |
| if (countryResult == null) { |
| // Country not recognized. |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneFromCountryAndNitz: lookupByCountry() country not recognized"); |
| return suggestionBuilder.build(); |
| } |
| |
| // If the country has a single zone, or it has multiple zones but the default zone is |
| // "boosted" (i.e. the country default is considered a good suggestion in most cases) then |
| // use it. |
| if (countryResult.quality == CountryResult.QUALITY_SINGLE_ZONE |
| || countryResult.quality == CountryResult.QUALITY_DEFAULT_BOOSTED) { |
| suggestionBuilder.setZoneId(countryResult.zoneId); |
| suggestionBuilder.setMatchType( |
| TelephonyTimeZoneSuggestion.MATCH_TYPE_NETWORK_COUNTRY_ONLY); |
| suggestionBuilder.setQuality(TelephonyTimeZoneSuggestion.QUALITY_SINGLE_ZONE); |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneFromCountryAndNitz: high quality country-only suggestion:" |
| + " countryResult=" + countryResult); |
| return suggestionBuilder.build(); |
| } |
| |
| // Quality is not high enough to set the zone using country only. |
| suggestionBuilder.addDebugInfo("findTimeZoneFromCountryAndNitz: country-only suggestion" |
| + " quality not high enough. countryResult=" + countryResult); |
| return suggestionBuilder.build(); |
| } |
| |
| /** |
| * Creates a {@link TelephonyTimeZoneSuggestion} using only network country code; works well on |
| * countries which only have one time zone or multiple zones with the same offset. |
| * |
| * @param countryIsoCode country code from network MCC |
| * @param whenMillis the time to use when looking at time zone rules data |
| */ |
| @NonNull |
| private TelephonyTimeZoneSuggestion findTimeZoneFromNetworkCountryCode( |
| int slotIndex, @NonNull String countryIsoCode, long whenMillis) { |
| Objects.requireNonNull(countryIsoCode); |
| if (TextUtils.isEmpty(countryIsoCode)) { |
| throw new IllegalArgumentException("countryIsoCode must not be empty"); |
| } |
| |
| TelephonyTimeZoneSuggestion.Builder suggestionBuilder = |
| new TelephonyTimeZoneSuggestion.Builder(slotIndex); |
| suggestionBuilder.addDebugInfo("findTimeZoneFromNetworkCountryCode:" |
| + " whenMillis=" + whenMillis + ", countryIsoCode=" + countryIsoCode); |
| CountryResult lookupResult = mTimeZoneLookupHelper.lookupByCountry( |
| countryIsoCode, whenMillis); |
| if (lookupResult != null) { |
| suggestionBuilder.setZoneId(lookupResult.zoneId); |
| suggestionBuilder.setMatchType( |
| TelephonyTimeZoneSuggestion.MATCH_TYPE_NETWORK_COUNTRY_ONLY); |
| |
| int quality; |
| if (lookupResult.quality == CountryResult.QUALITY_SINGLE_ZONE |
| || lookupResult.quality == CountryResult.QUALITY_DEFAULT_BOOSTED) { |
| quality = TelephonyTimeZoneSuggestion.QUALITY_SINGLE_ZONE; |
| } else if (lookupResult.quality == CountryResult.QUALITY_MULTIPLE_ZONES_SAME_OFFSET) { |
| quality = TelephonyTimeZoneSuggestion.QUALITY_MULTIPLE_ZONES_WITH_SAME_OFFSET; |
| } else if (lookupResult.quality |
| == CountryResult.QUALITY_MULTIPLE_ZONES_DIFFERENT_OFFSETS) { |
| quality = TelephonyTimeZoneSuggestion.QUALITY_MULTIPLE_ZONES_WITH_DIFFERENT_OFFSETS; |
| } else { |
| // This should never happen. |
| throw new IllegalArgumentException( |
| "lookupResult.quality not recognized: countryIsoCode=" + countryIsoCode |
| + ", whenMillis=" + whenMillis + ", lookupResult=" + lookupResult); |
| } |
| suggestionBuilder.setQuality(quality); |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneFromNetworkCountryCode: lookupResult=" + lookupResult); |
| } else { |
| suggestionBuilder.addDebugInfo( |
| "findTimeZoneFromNetworkCountryCode: Country not recognized?"); |
| } |
| return suggestionBuilder.build(); |
| } |
| |
| /** |
| * Returns true if the NITZ signal is definitely bogus, assuming that the country is correct. |
| */ |
| private boolean isNitzSignalOffsetInfoBogus(String countryIsoCode, NitzData nitzData) { |
| if (TextUtils.isEmpty(countryIsoCode)) { |
| // We cannot say for sure. |
| return false; |
| } |
| |
| boolean zeroOffsetNitz = nitzData.getLocalOffsetMillis() == 0; |
| return zeroOffsetNitz && !countryUsesUtc(countryIsoCode, nitzData); |
| } |
| |
| private boolean countryUsesUtc(String countryIsoCode, NitzData nitzData) { |
| return mTimeZoneLookupHelper.countryUsesUtc( |
| countryIsoCode, nitzData.getCurrentTimeInMillis()); |
| } |
| } |
