Fix push device registration

android/app/build.gradle.kts

@@ -22,8 +22,8 @@ android {
         applicationId = "xyz.kusoft.qmax"
         minSdk = 26
         targetSdk = 36
-        versionCode = 48
+        versionCode = 49
-        versionName = "0.1.47"
+        versionName = "0.1.48"
 
         buildConfigField("String", "QMAX_DEFAULT_SERVER_URL", "\"https://qmax.kusoft.xyz\"")
         buildConfigField("String", "QMAX_DEFAULT_PAIRING_CODE", "\"qmax-MxRq4h2HQBEIFs6k\"")

android/app/src/main/java/xyz/kusoft/qmax/core/QMaxRepository.kt

@@ -6,6 +6,7 @@ import android.content.ClipData
 import android.content.ActivityNotFoundException
 import android.net.Uri
 import android.provider.OpenableColumns
+import android.util.Log
 import androidx.core.content.FileProvider
 import com.google.firebase.messaging.FirebaseMessaging
 import kotlinx.coroutines.flow.Flow
@@ -268,23 +269,27 @@ class QMaxRepository(
         return withFreshSession(session) { api.submitMaxCode(it.serverUrl, it.accessToken, code) }
     }
 
-    suspend fun registerCurrentPushDevice(session: QMaxSession) {
+    suspend fun registerCurrentPushDevice(session: QMaxSession): Boolean {
         if (!FirebaseBootstrap.ensureInitialized(context)) {
-            return
+            Log.w(PushLogTag, "Firebase is not initialized; push device registration skipped")
+            return false
         }
 
         val token = FirebaseMessaging.getInstance().token.await()
-        registerPushDevice(session, token)
+        return registerPushDevice(session, token)
     }
 
-    suspend fun registerPushDevice(session: QMaxSession, firebaseToken: String) {
+    suspend fun registerPushDevice(session: QMaxSession, firebaseToken: String): Boolean {
         if (firebaseToken.isBlank()) {
-            return
+            Log.w(PushLogTag, "Firebase returned a blank FCM token")
+            return false
         }
 
         withFreshSession(session) {
             api.registerPushDevice(it.serverUrl, it.accessToken, firebaseToken)
         }
+        Log.i(PushLogTag, "Push device token registered with QMAX API")
+        return true
     }
 
     private suspend fun sharePayload(session: QMaxSession, text: String?, attachments: List<AttachmentDto>) {
@@ -494,6 +499,8 @@ class QMaxRepository(
     }
 }
 
+private const val PushLogTag = "QMaxPush"
+
 private data class SharedAttachment(
     val attachment: AttachmentDto,
     val file: File,

android/app/src/main/java/xyz/kusoft/qmax/ui/QMaxViewModel.kt

@@ -70,6 +70,8 @@ class QMaxViewModel(private val repository: QMaxRepository) : ViewModel() {
     private var chatSearchJob: Job? = null
     private var autoLoginJob: Job? = null
     private var pushRegisteredForToken: String? = null
+    private var pushRegistrationJob: Job? = null
+    private var pushRegistrationInFlightForToken: String? = null
     private var autoLoginAttempted = false
     private var pendingOpenChatId: String? = null
     private val locallyReadChatFingerprints = mutableMapOf<String, String>()
@@ -97,6 +99,9 @@ class QMaxViewModel(private val repository: QMaxRepository) : ViewModel() {
                     realtimeConnectJob?.cancel()
                     messagePollJob?.cancel()
                     presencePollJob?.cancel()
+                    pushRegistrationJob?.cancel()
+                    pushRegistrationInFlightForToken = null
+                    pushRegisteredForToken = null
                     realtime.disconnect()
                     if (!autoLoginAttempted && state.value.pairingCode.isNotBlank()) {
                         autoLoginAttempted = true
@@ -843,11 +848,46 @@ class QMaxViewModel(private val repository: QMaxRepository) : ViewModel() {
         if (pushRegisteredForToken == registrationKey) {
             return
         }
+        if (pushRegistrationJob?.isActive == true && pushRegistrationInFlightForToken == registrationKey) {
+            return
+        }
 
-        pushRegisteredForToken = registrationKey
+        pushRegistrationJob?.cancel()
-        viewModelScope.launch {
+        pushRegistrationInFlightForToken = registrationKey
-            runCatching {
+        pushRegistrationJob = viewModelScope.launch {
+            try {
+                var retryDelayMs = 0L
+                for (attempt in 1..PushRegistrationAttempts) {
+                    if (retryDelayMs > 0) {
+                        delay(retryDelayMs)
+                    }
+
+                    val registered = try {
                         repository.registerCurrentPushDevice(session)
+                    } catch (error: CancellationException) {
+                        throw error
+                    } catch (error: Throwable) {
+                        Log.w(LogTag, "push registration failed, attempt=$attempt", error)
+                        false
+                    }
+
+                    if (registered) {
+                        pushRegisteredForToken = registrationKey
+                        Log.i(LogTag, "push registration completed")
+                        return@launch
+                    }
+
+                    Log.w(LogTag, "push registration was not completed, attempt=$attempt")
+                    retryDelayMs = if (retryDelayMs == 0L) {
+                        InitialPushRegistrationRetryMs
+                    } else {
+                        (retryDelayMs * 2).coerceAtMost(MaxPushRegistrationRetryMs)
+                    }
+                }
+            } finally {
+                if (pushRegistrationInFlightForToken == registrationKey) {
+                    pushRegistrationInFlightForToken = null
+                }
             }
         }
     }
@@ -1036,5 +1076,8 @@ class QMaxViewModel(private val repository: QMaxRepository) : ViewModel() {
         const val ChatListTimeoutMs = 45_000L
         const val MessageSyncTimeoutMs = 120_000L
         const val AutoLoginDelayMs = 1_000L
+        const val PushRegistrationAttempts = 6
+        const val InitialPushRegistrationRetryMs = 15_000L
+        const val MaxPushRegistrationRetryMs = 120_000L
     }
 }

server/QMax.Api/Controllers/PushController.cs

@@ -10,7 +10,7 @@ namespace QMax.Api.Controllers;
 [ApiController]
 [Authorize]
 [Route("api/push")]
-public sealed class PushController(QMaxDbContext db) : ControllerBase
+public sealed class PushController(QMaxDbContext db, ILogger<PushController> logger) : ControllerBase
 {
     public sealed record RegisterPushDeviceRequest(string FirebaseToken, string Platform);
 
@@ -22,7 +22,12 @@ public sealed class PushController(QMaxDbContext db) : ControllerBase
             return BadRequest("firebaseToken is required.");
         }
 
-        var userId = User.GetUserId();
+        var userId = await ResolvePushUserIdAsync(User.GetUserId(), cancellationToken);
+        if (userId is null)
+        {
+            return Unauthorized();
+        }
+
         var device = await db.PushDevices.FirstOrDefaultAsync(x => x.FirebaseToken == request.FirebaseToken, cancellationToken);
         if (device is null)
         {
@@ -30,7 +35,7 @@ public sealed class PushController(QMaxDbContext db) : ControllerBase
             db.PushDevices.Add(device);
         }
 
-        device.UserId = userId;
+        device.UserId = userId.Value;
         device.Platform = string.IsNullOrWhiteSpace(request.Platform) ? "android" : request.Platform;
         device.UpdatedAt = DateTimeOffset.UtcNow;
         await db.SaveChangesAsync(cancellationToken);
@@ -51,4 +56,43 @@ public sealed class PushController(QMaxDbContext db) : ControllerBase
         await db.SaveChangesAsync(cancellationToken);
         return NoContent();
     }
+
+    private async Task<Guid?> ResolvePushUserIdAsync(Guid authenticatedUserId, CancellationToken cancellationToken)
+    {
+        if (await db.Users.AnyAsync(x => x.Id == authenticatedUserId, cancellationToken))
+        {
+            return authenticatedUserId;
+        }
+
+        var existingUserIds = await db.Users
+            .Select(x => x.Id)
+            .Take(2)
+            .ToArrayAsync(cancellationToken);
+
+        if (existingUserIds.Length == 1)
+        {
+            logger.LogWarning(
+                "Push registration used stale user {AuthenticatedUserId}; attaching device to single existing user {UserId}.",
+                authenticatedUserId,
+                existingUserIds[0]);
+            return existingUserIds[0];
+        }
+
+        if (existingUserIds.Length > 1)
+        {
+            logger.LogWarning(
+                "Push registration used missing user {AuthenticatedUserId}, but database has multiple users.",
+                authenticatedUserId);
+            return null;
+        }
+
+        db.Users.Add(new User
+        {
+            Id = authenticatedUserId,
+            DisplayName = User.Identity?.Name?.Trim() is { Length: > 0 } displayName
+                ? displayName
+                : "QMAX Owner"
+        });
+        return authenticatedUserId;
+    }
 }

tests/QMax.Tests/ApiSmokeTests.cs

@@ -158,6 +158,45 @@ public sealed class ApiSmokeTests : IDisposable
         Assert.Contains(chats, x => x.Title == "\u0410\u043d\u044e\u0442\u0430");
     }
 
+    [Fact]
+    public async Task PushRegistrationUsesSingleExistingUserWhenTokenUserIsStale()
+    {
+        using var factory = _factory.WithWebHostBuilder(builder =>
+        {
+            builder.ConfigureTestServices(services =>
+            {
+                services.RemoveAll<IHostedService>();
+            });
+        });
+        using var client = factory.CreateClient();
+        await LoginAsync(client);
+
+        Guid currentUserId;
+        using (var scope = factory.Services.CreateScope())
+        {
+            var db = scope.ServiceProvider.GetRequiredService<QMaxDbContext>();
+            db.UserSessions.RemoveRange(db.UserSessions);
+            db.Users.RemoveRange(db.Users);
+            var currentUser = new User { DisplayName = "QMAX Owner" };
+            db.Users.Add(currentUser);
+            await db.SaveChangesAsync();
+            currentUserId = currentUser.Id;
+        }
+
+        var response = await client.PostAsJsonAsync(
+            "/api/push/devices",
+            new { FirebaseToken = "stale-token-user-fcm-token", Platform = "android" });
+
+        await AssertStatusAsync(HttpStatusCode.NoContent, response);
+        using (var scope = factory.Services.CreateScope())
+        {
+            var db = scope.ServiceProvider.GetRequiredService<QMaxDbContext>();
+            var device = await db.PushDevices.SingleAsync();
+            Assert.Equal(currentUserId, device.UserId);
+            Assert.Equal("stale-token-user-fcm-token", device.FirebaseToken);
+        }
+    }
+
     [Fact]
     public async Task SyncMergesLateDiscoveredAttachmentsIntoExistingMessage()
     {