Improve hidden number detection

app/src/main/java/dummydomain/yetanothercallblocker/CallMonitoringService.java

@@ -27,7 +27,8 @@ public class CallMonitoringService extends Service {
     private static final Logger LOG = LoggerFactory.getLogger(CallMonitoringService.class);
 
     private final MyPhoneStateListener phoneStateListener = new MyPhoneStateListener();
-    private final CallReceiver callReceiver = new CallReceiver(true);
+    private final CallReceiver callReceiver = new CallReceiver(
+            PhoneStateHandler.Source.PHONE_STATE_BROADCAST_RECEIVER_MONITORING);
 
     private boolean monitoringStarted;
 
@@ -135,15 +136,17 @@ public class CallMonitoringService extends Service {
             }
 
             PhoneStateHandler phoneStateHandler = YacbHolder.getPhoneStateHandler();
+            PhoneStateHandler.Source source = PhoneStateHandler.Source.PHONE_STATE_LISTENER;
+
             switch (state) {
                 case TelephonyManager.CALL_STATE_IDLE:
-                    phoneStateHandler.onIdle(phoneNumber);
+                    phoneStateHandler.onIdle(source, phoneNumber);
                     break;
                 case TelephonyManager.CALL_STATE_RINGING:
-                    phoneStateHandler.onRinging(phoneNumber);
+                    phoneStateHandler.onRinging(source, phoneNumber);
                     break;
                 case TelephonyManager.CALL_STATE_OFFHOOK:
-                    phoneStateHandler.onOffHook(phoneNumber);
+                    phoneStateHandler.onOffHook(source, phoneNumber);
                     break;
             }
         }

app/src/main/java/dummydomain/yetanothercallblocker/CallReceiver.java

@@ -15,20 +15,20 @@ public class CallReceiver extends BroadcastReceiver {
 
     private static final Logger LOG = LoggerFactory.getLogger(CallReceiver.class);
 
-    private final boolean monitoringService;
+    private final PhoneStateHandler.Source source;
 
     @SuppressWarnings({"unused", "RedundantSuppression"}) // required for BroadcastReceivers
     public CallReceiver() {
-        this(false);
+        this(PhoneStateHandler.Source.PHONE_STATE_BROADCAST_RECEIVER);
     }
 
-    public CallReceiver(boolean monitoringService) {
+    public CallReceiver(PhoneStateHandler.Source source) {
-        this.monitoringService = monitoringService;
+        this.source = source;
     }
 
     @Override
     public void onReceive(Context context, Intent intent) {
-        LOG.debug("onReceive() invoked, monitoringService={}", monitoringService);
+        LOG.debug("onReceive() invoked, source={}", source);
 
         if (!TelephonyManager.ACTION_PHONE_STATE_CHANGED.equals(intent.getAction())
                 && !TelephonyManager.EXTRA_STATE_RINGING.equals(intent.getAction())) { // TODO: check
@@ -58,11 +58,11 @@ public class CallReceiver extends BroadcastReceiver {
 
         PhoneStateHandler phoneStateHandler = YacbHolder.getPhoneStateHandler();
         if (TelephonyManager.EXTRA_STATE_RINGING.equals(telephonyExtraState)) {
-            phoneStateHandler.onRinging(incomingNumber);
+            phoneStateHandler.onRinging(source, incomingNumber);
         } else if (TelephonyManager.EXTRA_STATE_OFFHOOK.equals(telephonyExtraState)) {
-            phoneStateHandler.onOffHook(incomingNumber);
+            phoneStateHandler.onOffHook(source, incomingNumber);
         } else if (TelephonyManager.EXTRA_STATE_IDLE.equals(telephonyExtraState)) {
-            phoneStateHandler.onIdle(incomingNumber);
+            phoneStateHandler.onIdle(source, incomingNumber);
         }
     }
 

app/src/main/java/dummydomain/yetanothercallblocker/PhoneStateHandler.java

@@ -3,6 +3,8 @@ package dummydomain.yetanothercallblocker;
 import android.content.Context;
 import android.text.TextUtils;
 
+import androidx.core.util.Predicate;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -21,6 +23,12 @@ import static dummydomain.yetanothercallblocker.EventUtils.postEvent;
 
 public class PhoneStateHandler {
 
+    public enum Source {
+        PHONE_STATE_LISTENER,
+        PHONE_STATE_BROADCAST_RECEIVER_MONITORING,
+        PHONE_STATE_BROADCAST_RECEIVER
+    }
+
     private static final Logger LOG = LoggerFactory.getLogger(PhoneStateHandler.class);
 
     private final Context context;
@@ -42,8 +50,8 @@ public class PhoneStateHandler {
         this.notificationService = notificationService;
     }
 
-    public void onRinging(String phoneNumber) {
+    public void onRinging(Source source, String phoneNumber) {
-        LOG.debug("onRinging({})", phoneNumber);
+        LOG.debug("onRinging({}, \"{}\")", source, phoneNumber);
 
         boolean ignore = false;
 
@@ -53,17 +61,30 @@ public class PhoneStateHandler {
                 return;
             }
 
-            // TODO: check
+            if (source == Source.PHONE_STATE_LISTENER) {
+                LOG.info("onRinging() treating null from PhoneStateListener as a hidden number");
+                phoneNumber = "";
+            } else if ((source == Source.PHONE_STATE_BROADCAST_RECEIVER_MONITORING
+                    || source == Source.PHONE_STATE_BROADCAST_RECEIVER)
+                    && isEventPresent(sameSourceAndNumber(source, null))
+                    && !isEventPresent(nonEmptyNumber())) {
+                LOG.info("onRinging() treating repeated null from PhoneStateBroadcastReceiver" +
+                        " as a hidden number");
+                phoneNumber = "";
+            }
+
+            if (phoneNumber == null) {
                 LOG.debug("onRinging() ignoring null");
                 ignore = true;
             }
+        }
 
-        if (!ignore && !shouldProcess(phoneNumber)) {
+        if (!ignore && isEventPresent(sameNumber(phoneNumber))) {
             LOG.debug("onRinging() ignoring repeated event");
             ignore = true;
         }
 
-        recordEvent(phoneNumber);
+        recordEvent(source, phoneNumber);
 
         if (ignore) return;
 
@@ -95,16 +116,16 @@ public class PhoneStateHandler {
         }
     }
 
-    public void onOffHook(String phoneNumber) {
+    public void onOffHook(Source source, String phoneNumber) {
-        LOG.debug("onOffHook({})", phoneNumber);
+        LOG.debug("onOffHook({}, \"{}\")", source, phoneNumber);
 
         isOffHook = true;
 
         postEvent(new CallOngoingEvent());
     }
 
-    public void onIdle(String phoneNumber) {
+    public void onIdle(Source source, String phoneNumber) {
-        LOG.debug("onIdle({})", phoneNumber);
+        LOG.debug("onIdle({}, \"{}\")", source, phoneNumber);
 
         isOffHook = false;
 
@@ -113,38 +134,56 @@ public class PhoneStateHandler {
         postEvent(new CallEndedEvent());
     }
 
-    private boolean shouldProcess(String phoneNumber) {
+    private static Predicate<CallEvent> sameNumber(String number) {
+        return event -> TextUtils.equals(event.number, number);
+    }
+
+    private static Predicate<CallEvent> sameSourceAndNumber(Source source, String number) {
+        return event -> event.source == source && TextUtils.equals(event.number, number);
+    }
+
+    private static Predicate<CallEvent> nonEmptyNumber() {
+        return event -> !TextUtils.isEmpty(event.number);
+    }
+
+    private boolean isEventPresent(Predicate<CallEvent> predicate) {
+        return findEvent(predicate) != null;
+    }
+
+    private CallEvent findEvent(Predicate<CallEvent> predicate) {
         // using 1 second ago as the cutoff point - consider everything older as unrelated events
         long cutoff = System.nanoTime() - TimeUnit.SECONDS.toNanos(1);
 
         if (lastEventTimestamp - cutoff < 0) { // no events in the last second
             lastEvents.clear();
-            return true;
+            return null;
         }
 
         for (ListIterator<CallEvent> it = lastEvents.listIterator(); it.hasNext(); ) {
             CallEvent event = it.next();
             if (event.timestamp - cutoff < 0) { // event is older than the cutoff point
                 it.remove();
-            } else if (TextUtils.equals(event.number, phoneNumber)) {
+            } else if (predicate.test(event)) {
-                return false; // don't process same event
+                return event;
             }
         }
 
-        return true;
+        return null;
     }
 
-    private void recordEvent(String phoneNumber) {
+    private void recordEvent(Source source, String phoneNumber) {
         long currentTimestamp = System.nanoTime();
-        lastEvents.add(new CallEvent(phoneNumber, currentTimestamp));
+        lastEvents.add(new CallEvent(source, phoneNumber, currentTimestamp));
         lastEventTimestamp = currentTimestamp;
     }
 
     private static class CallEvent {
+        final Source source;
         final String number;
         final long timestamp;
 
-        public CallEvent(String number, long timestamp) {
+        public CallEvent(Source source, String number, long timestamp) {
+            this.source = source;
             this.number = number;
             this.timestamp = timestamp;
         }

app/src/main/res/values-ru/strings.xml

@@ -24,7 +24,7 @@
     <string name="block_negative_sia">Блокировать по отзывам</string>
     <string name="block_negative_sia_numbers_summary">Блокировать звонки c номеров с отрицательным рейтингом</string>
     <string name="block_hidden_number">Блокировать скрытые номера</string>
-    <string name="block_hidden_number_summary">(Экспериментальная функция.) Блокировать звонки со скрытых номеров. Вероятно, работает лучше в \"Продвинутом режиме блокирования вызовов\". Пожалуйста, сообщите о своём опыте использования в репозитории на GitLab</string>
+    <string name="block_hidden_number_summary">Блокировать звонки со скрытых номеров. Может работать по-другому (лучше или хуже) в \"Продвинутом режиме блокирования вызовов\"</string>
     <string name="block_blacklisted_short">Блокировать из ЧС</string>
     <string name="block_blacklisted">Блокировать из чёрного списка</string>
     <string name="block_blacklisted_summary">Блокировать звонки с номеров добавленных в чёрный список</string>

app/src/main/res/values/strings.xml

@@ -97,7 +97,7 @@
     <string name="block_negative_sia">Block based on rating</string>
     <string name="block_negative_sia_numbers_summary">Block calls from numbers with negative rating (based on a community database)</string>
     <string name="block_hidden_number">Block hidden numbers</string>
-    <string name="block_hidden_number_summary">(Experimental.) Block calls from hidden numbers. Probably works better in \"Advanced call blocking mode\". Please report your experience on GitLab</string>
+    <string name="block_hidden_number_summary">Block calls from hidden numbers. May work differently (better or worse) in \"Advanced call blocking mode\"</string>
     <string name="block_blacklisted_short">Block blacklisted</string>
     <string name="block_blacklisted">Block blacklisted numbers</string>
     <string name="block_blacklisted_summary">Block calls from numbers added to the blacklist</string>