Fallback detection for Huawei device if no HMS SDK

* We should still detect a real Huawei with HMS only as
device_type 13 even if there is no HMS library in the app.

Author: jkasten2

OneSignalSDK/onesignal/src/main/java/com/onesignal/OSUtils.java

@@ -243,26 +243,37 @@ && getTargetSdkVersion(context) >= Build.VERSION_CODES.O) {
       return null;
    }
 
-   // TODO: Maybe able to switch to GoogleApiAvailability.isGooglePlayServicesAvailable to simplify
-   // However before doing so we need to test with an old version of the "Google Play services"
-   //   on the device to make sure it would still be counted as "SUCCESS".
-   // Or if we get back "SERVICE_VERSION_UPDATE_REQUIRED" then we may want to count that as successful too.
-   static boolean isGMSInstalledAndEnabled() {
+   private static boolean packageInstalledAndEnabled(@NonNull String packageName) {
       try {
          PackageManager pm = OneSignal.appContext.getPackageManager();
-         PackageInfo info = pm.getPackageInfo(GoogleApiAvailability.GOOGLE_PLAY_SERVICES_PACKAGE, PackageManager.GET_META_DATA);
+         PackageInfo info = pm.getPackageInfo(packageName, PackageManager.GET_META_DATA);
          return info.applicationInfo.enabled;
       } catch (PackageManager.NameNotFoundException e) {
          return false;
       }
    }
 
+   // TODO: Maybe able to switch to GoogleApiAvailability.isGooglePlayServicesAvailable to simplify
+   // However before doing so we need to test with an old version of the "Google Play services"
+   //   on the device to make sure it would still be counted as "SUCCESS".
+   // Or if we get back "SERVICE_VERSION_UPDATE_REQUIRED" then we may want to count that as successful too.
+   static boolean isGMSInstalledAndEnabled() {
+      return packageInstalledAndEnabled(GoogleApiAvailability.GOOGLE_PLAY_SERVICES_PACKAGE);
+   }
+
    private static final int HMS_AVAILABLE_SUCCESSFUL = 0;
    private static boolean isHMSCoreInstalledAndEnabled() {
       HuaweiApiAvailability availability = HuaweiApiAvailability.getInstance();
       return availability.isHuaweiMobileServicesAvailable(OneSignal.appContext) == HMS_AVAILABLE_SUCCESSFUL;
    }
 
+   private static final String HMS_CORE_SERVICES_PACKAGE = "com.huawei.hwid"; // = HuaweiApiAvailability.SERVICES_PACKAGE
+   // HuaweiApiAvailability is the recommend way to detect if "HMS Core" is available but this fallback
+   //   works even if the app developer doesn't include any HMS libraries in their app.
+   private static boolean isHMSCoreInstalledAndEnabledFallback() {
+      return packageInstalledAndEnabled(HMS_CORE_SERVICES_PACKAGE);
+   }
+
    private boolean supportsADM() {
       try {
          // Class only available on the FireOS and only when the following is in the AndroidManifest.xml.
@@ -310,13 +321,22 @@ int getDeviceType() {
 
       if (supportsGooglePush())
          return UserState.DEVICE_TYPE_ANDROID;
-      else {
-         // If the Huawei device has both FCM & HMS support we prefer FCM (Google push)
-         // HMS will only be used if it is the only option.
-         if (supportsHMS())
-            return UserState.DEVICE_TYPE_HUAWEI;
-      }
 
+      // Some Huawei devices have both FCM & HMS support, but prefer FCM (Google push) over HMS
+      if (supportsHMS())
+         return UserState.DEVICE_TYPE_HUAWEI;
+
+      // Start - Fallback logic
+      //    Libraries in the app (Google:FCM, HMS:PushKit) + Device may not have a valid combo
+      // Example: App with only the FCM library in it and a Huawei device with only HMS Core
+
+      if (isGMSInstalledAndEnabled())
+         return UserState.DEVICE_TYPE_ANDROID;
+
+      if (isHMSCoreInstalledAndEnabledFallback())
+         return UserState.DEVICE_TYPE_HUAWEI;
+
+      // Last fallback
       // Fallback to device_type 1 (Android) if there are no supported push channels on the device
       return UserState.DEVICE_TYPE_ANDROID;
    }

OneSignalSDK/unittest/src/test/java/com/onesignal/ShadowOSUtils.java

@@ -43,6 +43,9 @@ public boolean hasHMSPushKitLibrary() {
    public static boolean isHMSCoreInstalledAndEnabled() {
       return isHMSCoreInstalledAndEnabled;
    }
+   public static boolean isHMSCoreInstalledAndEnabledFallback() {
+      return isHMSCoreInstalledAndEnabled;
+   }
 
    public static void supportsHMS(boolean value) {
       hasHMSPushKitLibrary = true;

OneSignalSDK/unittest/src/test/java/com/test/onesignal/DeviceTypeTestsRunner.java

@@ -115,6 +115,18 @@ public void hasFCMButNoGMSOnDeviceAndHasHMS_isHuawei() {
         assertEquals(DEVICE_TYPE_HUAWEI, getDeviceType());
     }
 
+    @Test
+    public void noPushSDKsAndOnlyHMSCoreInstalled_isHuawei() {
+        ShadowOSUtils.isHMSCoreInstalledAndEnabled = true;
+        assertEquals(DEVICE_TYPE_HUAWEI, getDeviceType());
+    }
+
+    @Test
+    public void noPushSDKsAndOnlyGoogleServicesInstalled_isAndroid() {
+        ShadowOSUtils.isGMSInstalledAndEnabled = true;
+        assertEquals(DEVICE_TYPE_ANDROID, getDeviceType());
+    }
+
     @Test
     public void supportsFCMAndADM_PreferADM() {
         ShadowOSUtils.isGMSInstalledAndEnabled = true;