feat: warn if UP is disabled on FDroid variant

Displays a warning in the notifications settings fragment, if
UnifiedPush is disabled (or cannot be enabled). The warning will be only
displayed on the FDroid build variant, since other versions use FCM by
default.

mastodon/src/main/java/org/joinmastodon/android/fragments/settings/SettingsNotificationsFragment.java

@@ -1,7 +1,5 @@
 package org.joinmastodon.android.fragments.settings;
 
-import static org.unifiedpush.android.connector.UnifiedPush.getDistributor;
-
 import android.app.AlertDialog;
 import android.app.NotificationManager;
 import android.content.Intent;
@@ -15,6 +13,7 @@
 import android.widget.RelativeLayout;
 import android.widget.TextView;
 
+import org.joinmastodon.android.BuildConfig;
 import org.joinmastodon.android.GlobalUserPreferences;
 import org.joinmastodon.android.R;
 import org.joinmastodon.android.api.PushSubscriptionManager;
@@ -48,6 +47,7 @@ public class SettingsNotificationsFragment extends BaseSettingsFragment<Void>{
 	private HideableSingleViewRecyclerAdapter bannerAdapter;
 	private ImageView bannerIcon;
 	private TextView bannerText;
+	private TextView bannerTitle;
 	private Button bannerButton;
 
 	private CheckableListItem<Void> mentionsItem, boostsItem, favoritesItem, followersItem, pollsItem;
@@ -72,7 +72,7 @@ public void onCreate(Bundle savedInstanceState){
 		lp=AccountSessionManager.get(accountID).getLocalPreferences();
 
 		getPushSubscription();
-		useUnifiedPush=!getDistributor(getContext()).isEmpty();
+		useUnifiedPush=!UnifiedPush.getDistributor(getContext()).isEmpty();
 
 		onDataLoaded(List.of(
 				pauseItem=new CheckableListItem<>(getString(R.string.pause_all_notifications), getPauseItemSubtitle(), CheckableListItem.Style.SWITCH, false, R.drawable.ic_fluent_alert_snooze_24_regular, i->onPauseNotificationsClick(false)),
@@ -158,6 +158,7 @@ protected void onShown(){
 	@Override
 	protected RecyclerView.Adapter<?> getAdapter(){
 		View banner=getActivity().getLayoutInflater().inflate(R.layout.item_settings_banner, list, false);
+		bannerTitle=banner.findViewById(R.id.title);
 		bannerText=banner.findViewById(R.id.text);
 		bannerIcon=banner.findViewById(R.id.icon);
 		bannerButton=banner.findViewById(R.id.button);
@@ -315,6 +316,20 @@ private void updateBanner(){
 			bannerText.setText(R.string.notifications_disabled_in_system);
 			bannerButton.setText(R.string.open_system_notification_settings);
 			bannerButton.setOnClickListener(v->openSystemNotificationSettings());
+		}else if(BuildConfig.BUILD_TYPE.equals("fdroidRelease") && UnifiedPush.getDistributor(getContext()).isEmpty()){
+			bannerAdapter.setVisible(true);
+			bannerIcon.setImageResource(R.drawable.ic_fluent_warning_24_filled);
+			bannerTitle.setVisibility(View.VISIBLE);
+			bannerTitle.setText(R.string.mo_settings_unifiedpush_warning);
+			if(UnifiedPush.getDistributors(getContext(), new ArrayList<>()).isEmpty()) {
+				bannerText.setText(R.string.mo_settings_unifiedpush_warning_no_distributors);
+				bannerButton.setText(R.string.info);
+				bannerButton.setOnClickListener(v->UiUtils.launchWebBrowser(getContext(), "https://unifiedpush.org/"));
+			} else {
+				bannerText.setText(R.string.mo_settings_unifiedpush_warning_disabled);
+				bannerButton.setText(R.string.mo_settings_unifiedpush_enable);
+				bannerButton.setOnClickListener(v->onUnifiedPushClick());
+			}
 		}else if(pauseTime>System.currentTimeMillis()){
 			bannerAdapter.setVisible(true);
 			bannerIcon.setImageResource(R.drawable.ic_fluent_alert_snooze_24_regular);
@@ -327,7 +342,7 @@ private void updateBanner(){
 	}
 
 	private void onUnifiedPushClick(){
-		if(getDistributor(getContext()).isEmpty()){
+		if(UnifiedPush.getDistributor(getContext()).isEmpty()){
 			List<String> distributors = UnifiedPush.getDistributors(getContext(), new ArrayList<>());
 			showUnifiedPushRegisterDialog(distributors);
 			return;

mastodon/src/main/res/values/strings_mo.xml

@@ -113,6 +113,10 @@
 	<string name="mo_recent_emoji_cleared">Recent emoji cleared</string>
 	<string name="mo_show_media_preview">Show media preview in timelines</string>
 	<string name="mo_notification_filter_reset">Reset to default</string>
+	<string name="mo_settings_unifiedpush_warning">UnifiedPush not enabled</string>
+	<string name="mo_settings_unifiedpush_warning_no_distributors">No UnifiedPush Distributors installed. You will not receive any notifications.</string>
+	<string name="mo_settings_unifiedpush_warning_disabled">UnifiedPush is not enabled. You will not receive any notifications.</string>
+	<string name="mo_settings_unifiedpush_enable">Enable</string>
 
 	<!--	Temporary Strings. They exist in strings_sk.xml, but are not available on Megalodon's weblate-->
 	<string name="mo_muted_accounts">Muted accounts</string>