fix: show new-mail notifications when the app is open in the background but not on screen #94

android/app/src/main/java/com/anonymous/bulwarkmobile/BulwarkMessagingService.kt

@@ -33,14 +33,7 @@ class BulwarkMessagingService : FirebaseMessagingService() {
         // they feed (device sync, #34); only mail needs the push task.
         val mail = DeviceSyncPushRouter.route(applicationContext, data)
 
-        // Hand off to JS via a headless task only when the app isn't already
-        // running in the foreground - HeadlessJsTaskContext throws if started
-        // while foreground. When the app is open, the main JS instance already
-        // receives JMAP push directly, so the fcm:message event below is
-        // sufficient for it to refresh state.
-        if (mail && !isAppInForeground()) {
-            startHeadlessTask(applicationContext, data)
-        }
+        startTaskUnlessInForeground(applicationContext, data, mail)
 
         val params = Arguments.createMap().apply {
             val dataMap = Arguments.createMap()
@@ -58,13 +51,29 @@ class BulwarkMessagingService : FirebaseMessagingService() {
         private const val TAG = "BulwarkPush"
         private const val START_WAKE_LOCK_MS = 10_000L
 
-        // Shared with BulwarkUnifiedPushService - a push arriving over either
-        // transport is dispatched the same way.
-        fun isAppInForeground(): Boolean {
+        /**
+         * Runs the push task for a mail push unless the app's screen is
+         * resumed: then the user is looking at the app, which syncs over its
+         * own event stream, and HeadlessJsTaskContext would refuse the task.
+         * Shared with BulwarkUnifiedPushService, so a push arriving over
+         * either transport is dispatched the same way.
+         *
+         * The process importance is no measure of that (#94): an app paused
+         * under a translucent screen, or kept important by anything bound to
+         * it, counts as foreground, and its pushes ended without a
+         * notification.
+         */
+        fun startTaskUnlessInForeground(context: Context, data: Map<String, String>, mail: Boolean) {
+            val foreground = MainActivity.isInForeground
+            Log.i(TAG, "Push: mail=$mail foreground=$foreground importance=${processImportance()}")
+            if (mail && !foreground) startHeadlessTask(context, data)
+        }
+
+        /** For the log only. */
+        private fun processImportance(): Int {
             val info = ActivityManager.RunningAppProcessInfo()
             ActivityManager.getMyMemoryState(info)
-            return info.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND ||
-                info.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_VISIBLE
+            return info.importance
         }
 
         fun startHeadlessTask(context: Context, data: Map<String, String>) {

android/app/src/main/java/com/anonymous/bulwarkmobile/BulwarkUnifiedPushService.kt

@@ -35,9 +35,7 @@ class BulwarkUnifiedPushService : PushService() {
         // Same routing as FCM: contact and calendar changes request device
         // syncs, and only mail starts the push task.
         val mail = DeviceSyncPushRouter.route(applicationContext, data)
-        if (mail && !BulwarkMessagingService.isAppInForeground()) {
-            BulwarkMessagingService.startHeadlessTask(applicationContext, data)
-        }
+        BulwarkMessagingService.startTaskUnlessInForeground(applicationContext, data, mail)
 
         // Same event name and shape as the FCM path so the foreground JS
         // handler (App.tsx addMessageListener) works transport-agnostically.

android/app/src/main/java/com/anonymous/bulwarkmobile/MainActivity.kt

@@ -23,6 +23,16 @@ class MainActivity : ReactActivity() {
     ShareIntentStore.captureFromIntent(intent, contentResolver)
   }
 
+  override fun onResume() {
+    super.onResume()
+    isInForeground = true
+  }
+
+  override fun onPause() {
+    isInForeground = false
+    super.onPause()
+  }
+
   override fun onNewIntent(intent: Intent) {
     ShareIntentStore.rewriteSendToAsView(intent)
     super.onNewIntent(intent)
@@ -73,4 +83,16 @@ class MainActivity : ReactActivity() {
       // because it's doing more than [Activity.moveTaskToBack] in fact.
       super.invokeDefaultOnBackPressed()
   }
+
+  companion object {
+    /**
+     * Whether the app's screen is resumed, the state in which React Native
+     * refuses to start a headless task (HeadlessJsTaskContext). Pushes read
+     * it to decide whether the push task runs (BulwarkMessagingService).
+     */
+    @Volatile
+    @JvmStatic
+    var isInForeground = false
+      private set
+  }
 }