Add retransmission handling

lib/providers/connection_provider.dart

@@ -249,7 +249,10 @@ class ConnectionProvider with ChangeNotifier {
         await Future.delayed(const Duration(milliseconds: 300));
 
         if (pendingOp.messageId != null) {
-          _messageDeliveryTracker.trackPendingMessage(pendingOp.messageId!);
+          _messageDeliveryTracker.trackPendingDirectMessage(
+            pendingOp.messageId!,
+            pendingOp.contactPublicKey,
+          );
         }
 
         await _activeService.sendTextMessage(
@@ -352,7 +355,11 @@ class ConnectionProvider with ChangeNotifier {
 
     service.onMessageSent =
         (expectedAckTag, suggestedTimeoutMs, isFloodMode, contactPublicKey) {
-          final messageId = _messageDeliveryTracker.popPendingMessageId();
+          final messageId = contactPublicKey != null
+              ? _messageDeliveryTracker.popPendingDirectMessageId(
+                  contactPublicKey,
+                )
+              : _messageDeliveryTracker.popPendingMessageId();
           if (messageId != null) {
             _messageDeliveryTracker.mapAckTagToMessageId(
               expectedAckTag,
@@ -1148,7 +1155,10 @@ class ConnectionProvider with ChangeNotifier {
       // The MessagesProvider now uses simple ACK tag → recipientPublicKey mapping.
       // We still track here for the SENT response callback to work.
       if (messageId != null) {
-        _messageDeliveryTracker.trackPendingMessage(messageId);
+        _messageDeliveryTracker.trackPendingDirectMessage(
+          messageId,
+          contactPublicKey,
+        );
         debugPrint('  📝 Tracked pending message: $messageId');
       }
 

lib/providers/helpers/message_delivery_tracker.dart

@@ -1,3 +1,5 @@
+import 'dart:typed_data';
+
 /// Message delivery tracking helper
 ///
 /// Manages message delivery tracking for sent messages, including:
@@ -16,6 +18,9 @@ class MessageDeliveryTracker {
   /// Messages tracked here before sending, popped when RESP_CODE_SENT arrives
   final List<String> _pendingMessageIds = [];
 
+  /// Contact-scoped FIFOs for matching direct-message SENT responses.
+  final Map<String, List<String>> _pendingMessageIdsByContact = {};
+
   /// Map of ACK tag to message ID for delivery confirmation
   final Map<int, String> _ackTagToMessageId = {};
 
@@ -33,6 +38,15 @@ class MessageDeliveryTracker {
     _pendingMessageIds.add(messageId);
   }
 
+  /// Track a pending direct message ID for a specific contact.
+  void trackPendingDirectMessage(String messageId, Uint8List contactPublicKey) {
+    trackPendingMessage(messageId);
+    final contactKey = _contactKey(contactPublicKey);
+    _pendingMessageIdsByContact
+        .putIfAbsent(contactKey, () => [])
+        .add(messageId);
+  }
+
   /// Pop the next pending message ID from FIFO queue
   ///
   /// Called when RESP_CODE_SENT arrives. Returns null if queue empty.
@@ -43,6 +57,24 @@ class MessageDeliveryTracker {
     return _pendingMessageIds.removeAt(0);
   }
 
+  /// Pop the next pending direct message ID for a specific contact.
+  ///
+  /// Falls back to the legacy global FIFO if the contact queue is empty.
+  String? popPendingDirectMessageId(Uint8List contactPublicKey) {
+    final contactKey = _contactKey(contactPublicKey);
+    final queue = _pendingMessageIdsByContact[contactKey];
+    if (queue == null || queue.isEmpty) {
+      return popPendingMessageId();
+    }
+
+    final messageId = queue.removeAt(0);
+    if (queue.isEmpty) {
+      _pendingMessageIdsByContact.remove(contactKey);
+    }
+    _pendingMessageIds.remove(messageId);
+    return messageId;
+  }
+
   /// Map ACK tag to message ID after RESP_CODE_SENT received
   ///
   /// Creates bidirectional mapping for efficient cleanup and tracking.
@@ -86,6 +118,17 @@ class MessageDeliveryTracker {
       _ackTagToMessageId.remove(ackTag);
       _ackTagTimestamps.remove(ackTag);
     }
+    _pendingMessageIds.remove(messageId);
+    final emptyKeys = <String>[];
+    for (final entry in _pendingMessageIdsByContact.entries) {
+      entry.value.remove(messageId);
+      if (entry.value.isEmpty) {
+        emptyKeys.add(entry.key);
+      }
+    }
+    for (final key in emptyKeys) {
+      _pendingMessageIdsByContact.remove(key);
+    }
   }
 
   /// Clean up stale ACK mappings
@@ -114,6 +157,7 @@ class MessageDeliveryTracker {
   /// Clear all tracking state
   void clearTracking() {
     _pendingMessageIds.clear();
+    _pendingMessageIdsByContact.clear();
     _ackTagToMessageId.clear();
     _messageIdToAckTag.clear();
     _ackTagTimestamps.clear();
@@ -133,9 +177,7 @@ class MessageDeliveryTracker {
   /// Get oldest pending ACK timestamp (for debugging)
   DateTime? get oldestPendingTimestamp {
     if (_ackTagTimestamps.isEmpty) return null;
-    return _ackTagTimestamps.values.reduce(
+    return _ackTagTimestamps.values.reduce((a, b) => a.isBefore(b) ? a : b);
-      (a, b) => a.isBefore(b) ? a : b,
-    );
   }
 
   /// Get diagnostic info for debugging
@@ -145,6 +187,15 @@ class MessageDeliveryTracker {
       'shouldRateLimit': shouldRateLimit,
       'oldestPending': oldestPendingTimestamp?.toIso8601String(),
       'ackTags': _ackTagToMessageId.keys.toList(),
+      'pendingByContact': _pendingMessageIdsByContact.map(
+        (key, value) => MapEntry(key, value.length),
+      ),
     };
   }
+
+  String _contactKey(Uint8List contactPublicKey) {
+    return contactPublicKey
+        .map((b) => b.toRadixString(16).padLeft(2, '0'))
+        .join();
+  }
 }

lib/providers/messages_provider.dart

@@ -28,6 +28,9 @@ class MessagesProvider with ChangeNotifier {
   // Key: message ID (not ACK tag, since multiple messages can share same ACK)
   final Map<String, Timer> _timeoutTimers = {};
 
+  // Recently completed ACKs are kept briefly to ignore duplicate confirms.
+  final Map<int, DateTime> _completedAckHistory = {};
+
   // Retry management
   final MessageRetryManager _retryManager = MessageRetryManager();
 
@@ -906,11 +909,13 @@ class MessagesProvider with ChangeNotifier {
       final (groupId, recipientPublicKey) = groupMapping;
       debugPrint('  ✅ This is part of a grouped message: $groupId');
 
-      // Update the recipient status to "sent" in the grouped message
+      // ACK-tracked recipients stay pending until the delivery confirm arrives.
       updateGroupedMessageRecipientStatus(
         groupId,
         recipientPublicKey,
-        MessageDeliveryStatus.sent,
+        expectedAckTag > 0
+            ? MessageDeliveryStatus.sending
+            : MessageDeliveryStatus.sent,
       );
 
       // Track the ACK for this specific recipient
@@ -1022,7 +1027,9 @@ class MessagesProvider with ChangeNotifier {
       );
 
       final updatedMessage = message.copyWith(
-        deliveryStatus: MessageDeliveryStatus.sent,
+        deliveryStatus: expectedAckTag > 0
+            ? MessageDeliveryStatus.sending
+            : MessageDeliveryStatus.sent,
         expectedAckTag: expectedAckTag > 0 ? expectedAckTag : null,
         suggestedTimeoutMs: suggestedTimeoutMs > 0 ? suggestedTimeoutMs : null,
       );
@@ -1245,6 +1252,7 @@ class MessagesProvider with ChangeNotifier {
 
   /// Update message status to delivered with RTT
   void markMessageDelivered(int ackCode, int roundTripTimeMs) {
+    _cleanupCompletedAckHistory();
     debugPrint(
       '🔍 [MessagesProvider] markMessageDelivered called with ACK: $ackCode, RTT: ${roundTripTimeMs}ms',
     );
@@ -1296,6 +1304,7 @@ class MessagesProvider with ChangeNotifier {
         );
         _ackTagToRecipients.remove(ackCode);
         _pendingSentMessages.remove(ackCode);
+        _rememberCompletedAck(ackCode);
       }
 
       debugPrint(
@@ -1339,6 +1348,7 @@ class MessagesProvider with ChangeNotifier {
 
         // Remove from pending
         _pendingSentMessages.remove(ackCode);
+        _rememberCompletedAck(ackCode);
 
         // Clear retry tracking on successful delivery
         _retryManager.clearRetry(message.id);
@@ -1362,6 +1372,12 @@ class MessagesProvider with ChangeNotifier {
         );
       }
     } else {
+      if (_completedAckHistory.containsKey(ackCode)) {
+        debugPrint(
+          'ℹ️ [MessagesProvider] Duplicate/late ACK $ackCode ignored (already completed)',
+        );
+        return;
+      }
       debugPrint(
         '⚠️ [MessagesProvider] No pending message found for ACK code: $ackCode',
       );
@@ -1482,18 +1498,31 @@ class MessagesProvider with ChangeNotifier {
         debugPrint(
           '⏰ [MessagesProvider] Executing retry $nextAttempt for message $messageId',
         );
+        final currentIndex = _messages.indexWhere((m) => m.id == messageId);
+        if (currentIndex == -1) {
+          return;
+        }
+        final currentMessage = _messages[currentIndex];
+        if (currentMessage.deliveryStatus == MessageDeliveryStatus.delivered) {
+          return;
+        }
+
         if (sendMessageCallback != null) {
-          await sendMessageCallback!(
+          final queued = await sendMessageCallback!(
             contactPublicKey: contact.publicKey,
             text: message.text,
             messageId: messageId,
             contact: contact,
             retryAttempt: nextAttempt,
           );
+          if (!queued) {
+            _markAsPermanentlyFailed(messageId, currentMessage);
+          }
         } else {
           debugPrint(
             '⚠️ [MessagesProvider] sendMessageCallback not set, cannot retry',
           );
+          _markAsPermanentlyFailed(messageId, currentMessage);
         }
       });
 
@@ -1529,17 +1558,21 @@ class MessagesProvider with ChangeNotifier {
 
       // Send with flood mode (no retry after this)
       if (sendMessageCallback != null) {
-        await sendMessageCallback!(
+        final queued = await sendMessageCallback!(
           contactPublicKey: contact.publicKey,
           text: message.text,
           messageId: messageId,
           contact: contact,
           retryAttempt: 0, // Reset attempt for flood
         );
+        if (!queued) {
+          _markAsPermanentlyFailed(messageId, _messages[index]);
+        }
       } else {
         debugPrint(
           '⚠️ [MessagesProvider] sendMessageCallback not set, cannot send flood',
         );
+        _markAsPermanentlyFailed(messageId, _messages[index]);
       }
 
       _persistMessages();
@@ -1608,17 +1641,21 @@ class MessagesProvider with ChangeNotifier {
 
     // Send again
     if (sendMessageCallback != null) {
-      await sendMessageCallback!(
+      final queued = await sendMessageCallback!(
         contactPublicKey: contact.publicKey,
         text: message.text,
         messageId: messageId,
         contact: contact,
         retryAttempt: 0,
       );
+      if (!queued) {
+        _markAsPermanentlyFailed(messageId, _messages[index]);
+      }
     } else {
       debugPrint(
         '⚠️ [MessagesProvider] sendMessageCallback not set, cannot resend',
       );
+      _markAsPermanentlyFailed(messageId, _messages[index]);
     }
 
     _persistMessages();
@@ -1631,10 +1668,29 @@ class MessagesProvider with ChangeNotifier {
       timer.cancel();
     }
     _timeoutTimers.clear();
+    _completedAckHistory.clear();
 
     // Clear retry manager
     _retryManager.clearAll();
 
     super.dispose();
   }
+
+  void _rememberCompletedAck(int ackCode) {
+    _completedAckHistory[ackCode] = DateTime.now();
+    _cleanupCompletedAckHistory();
+  }
+
+  void _cleanupCompletedAckHistory({
+    Duration maxAge = const Duration(minutes: 15),
+  }) {
+    final cutoff = DateTime.now().subtract(maxAge);
+    final staleAcks = _completedAckHistory.entries
+        .where((entry) => entry.value.isBefore(cutoff))
+        .map((entry) => entry.key)
+        .toList();
+    for (final ack in staleAcks) {
+      _completedAckHistory.remove(ack);
+    }
+  }
 }

lib/screens/home_screen.dart

@@ -46,9 +46,9 @@ class HomeScreen extends StatefulWidget {
   State<HomeScreen> createState() => _HomeScreenState();
 }
 
-class _HomeScreenState extends State<HomeScreen>
+class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
-    with SingleTickerProviderStateMixin {
   late TabController _tabController;
+  late final AppProvider _appProvider;
   int _currentIndex = 0;
   bool _isMapFullscreen = false;
   bool _showRxTxIndicators = true;
@@ -74,9 +74,13 @@ class _HomeScreenState extends State<HomeScreen>
   @override
   void initState() {
     super.initState();
+    _appProvider = context.read<AppProvider>();
+    _isMapEnabled = _appProvider.isMapEnabled;
+    _isContactsEnabled = _appProvider.isContactsEnabled;
+    _appProvider.addListener(_handleAppProviderChanged);
+
     // Initialize synchronously so first build always has a valid controller.
     _initTabController();
-    _loadTabVisibilityAndInitTabs();
     _loadRxTxPreference();
 
     // Show permission dialog after the first frame if needed
@@ -87,19 +91,6 @@ class _HomeScreenState extends State<HomeScreen>
     }
   }
 
-  Future<void> _loadTabVisibilityAndInitTabs() async {
-    final prefs = await SharedPreferences.getInstance();
-    final mapEnabled = prefs.getBool('map_enabled') ?? true;
-    final contactsEnabled = prefs.getBool('contacts_enabled') ?? true;
-    if (!mounted) return;
-    if (_isMapEnabled != mapEnabled || _isContactsEnabled != contactsEnabled) {
-      _updateTabController(
-        mapEnabled: mapEnabled,
-        contactsEnabled: contactsEnabled,
-      );
-    }
-  }
-
   void _initTabController() {
     _tabController = TabController(length: _enabledTabs.length, vsync: this);
     _tabController.addListener(_onTabChanged);
@@ -110,6 +101,14 @@ class _HomeScreenState extends State<HomeScreen>
     });
   }
 
+  void _handleAppProviderChanged() {
+    if (!mounted) return;
+    _updateTabController(
+      mapEnabled: _appProvider.isMapEnabled,
+      contactsEnabled: _appProvider.isContactsEnabled,
+    );
+  }
+
   void _onTabChanged() {
     final previousTab = _currentTab;
     final nextIndex = _tabController.index;
@@ -136,15 +135,21 @@ class _HomeScreenState extends State<HomeScreen>
     }
 
     final oldTabs = _enabledTabs;
-    final oldIndex = _tabController.index;
+    final oldIndex = oldTabs.isEmpty
+        ? 0
+        : _tabController.index.clamp(0, oldTabs.length - 1);
     final oldTab = oldTabs[oldIndex];
 
     final oldController = _tabController;
     oldController.removeListener(_onTabChanged);
+    oldController.dispose();
 
     // Update state
     _isMapEnabled = mapEnabled;
     _isContactsEnabled = contactsEnabled;
+    if (!_isMapEnabled) {
+      _isMapFullscreen = false;
+    }
 
     final newTabs = _enabledTabs;
     final newIndex = newTabs.indexOf(oldTab);
@@ -157,11 +162,7 @@ class _HomeScreenState extends State<HomeScreen>
     _tabController.index = _currentIndex;
 
     setState(() {});
-
+    _handleTabActivated(_currentTab);
-    // Dispose old controller after widgets have rebound to the new controller.
-    WidgetsBinding.instance.addPostFrameCallback((_) {
-      oldController.dispose();
-    });
   }
 
   void _navigateToTab(_HomeTab tab) {
@@ -199,6 +200,7 @@ class _HomeScreenState extends State<HomeScreen>
 
   @override
   void dispose() {
+    _appProvider.removeListener(_handleAppProviderChanged);
     _tabController.removeListener(_onTabChanged);
     _tabController.dispose();
     super.dispose();
@@ -343,18 +345,7 @@ class _HomeScreenState extends State<HomeScreen>
       messagesProvider.setLocalizations(localizations);
     }
 
-    // Check if tab visibility settings changed and update tab controller
+    context.watch<AppProvider>();
-    final appProvider = context.watch<AppProvider>();
-    if (_isMapEnabled != appProvider.isMapEnabled ||
-        _isContactsEnabled != appProvider.isContactsEnabled) {
-      WidgetsBinding.instance.addPostFrameCallback((_) {
-        if (!mounted) return;
-        _updateTabController(
-          mapEnabled: appProvider.isMapEnabled,
-          contactsEnabled: appProvider.isContactsEnabled,
-        );
-      });
-    }
 
     final enabledTabs = _enabledTabs;
     final isMapTabActive = _currentTab == _HomeTab.map;

lib/screens/map_tab.dart

@@ -1349,9 +1349,6 @@ class _MapTabState extends State<MapTab> with AutomaticKeepAliveClientMixin {
           // SAR marker data is automatically added by SarMessageParser.enhanceMessage in MessagesProvider
         );
 
-        // Add to messages list with "sending" status
-        messagesProvider.addSentMessage(sentMessage);
-
         // Look up the room contact for path logging
         final contactsProvider = context.read<ContactsProvider>();
         final roomContact = contactsProvider.contacts.where((c) {
@@ -1359,6 +1356,9 @@ class _MapTabState extends State<MapTab> with AutomaticKeepAliveClientMixin {
               c.publicKey.matches(roomPublicKey);
         }).firstOrNull;
 
+        // Add to messages list with "sending" status
+        messagesProvider.addSentMessage(sentMessage, contact: roomContact);
+
         // Send SAR message to selected room (persisted and immutable)
         final sentSuccessfully = await connectionProvider.sendTextMessage(
           contactPublicKey: roomPublicKey!,

lib/screens/messages_tab.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:convert';
 import 'dart:io' show Platform;
 import 'package:flutter/foundation.dart' show kIsWeb;
 import 'dart:math' as math;
@@ -44,11 +45,13 @@ class MessagesTab extends StatefulWidget {
 }
 
 class _MessagesTabState extends State<MessagesTab> {
+  static const int _maxContactMessageBytes = 156;
+  static const int _maxChannelMessageBytes = 127;
+
   final TextEditingController _textController = TextEditingController();
   final FocusNode _focusNode = FocusNode();
   final ScrollController _scrollController = ScrollController();
-  int _characterCount = 0;
+  int _messageByteCount = 0;
-  static const int _maxCharacters = 160;
   String? _highlightedMessageId;
   Timer? _highlightTimer; // Timer for clearing message highlight
 
@@ -166,10 +169,44 @@ class _MessagesTabState extends State<MessagesTab> {
 
   void _updateCharacterCount() {
     setState(() {
-      _characterCount = _textController.text.length;
+      _messageByteCount = utf8.encode(_textController.text).length;
     });
   }
 
+  int get _maxMessageBytes =>
+      _destinationType == MessageDestinationPreferences.destinationTypeChannel
+      ? _maxChannelMessageBytes
+      : _maxContactMessageBytes;
+
+  TextInputFormatter get _messageByteLimiter =>
+      TextInputFormatter.withFunction((oldValue, newValue) {
+        if (utf8.encode(newValue.text).length <= _maxMessageBytes) {
+          return newValue;
+        }
+        return oldValue;
+      });
+
+  void _enforceMessageByteLimit() {
+    final currentText = _textController.text;
+    if (utf8.encode(currentText).length <= _maxMessageBytes) {
+      _updateCharacterCount();
+      return;
+    }
+
+    var truncated = currentText;
+    while (truncated.isNotEmpty &&
+        utf8.encode(truncated).length > _maxMessageBytes) {
+      truncated = truncated.substring(0, truncated.length - 1);
+    }
+
+    _textController.value = _textController.value.copyWith(
+      text: truncated,
+      selection: TextSelection.collapsed(offset: truncated.length),
+      composing: TextRange.empty,
+    );
+    _updateCharacterCount();
+  }
+
   /// Load saved message destination from preferences
   Future<void> _loadSavedDestination() async {
     final savedDestination =
@@ -211,6 +248,8 @@ class _MessagesTabState extends State<MessagesTab> {
         await MessageDestinationPreferences.clearDestination();
       }
     }
+
+    _enforceMessageByteLimit();
   }
 
   /// Show recipient selector bottom sheet
@@ -250,6 +289,8 @@ class _MessagesTabState extends State<MessagesTab> {
       _selectedRecipient = recipient;
     });
 
+    _enforceMessageByteLimit();
+
     // Save to preferences
     await MessageDestinationPreferences.setDestination(
       type,
@@ -383,7 +424,7 @@ class _MessagesTabState extends State<MessagesTab> {
     );
 
     // Add to messages list with "sending" status
-    messagesProvider.addSentMessage(sentMessage);
+    messagesProvider.addSentMessage(sentMessage, contact: _selectedRecipient);
 
     // Send to selected channel
     await connectionProvider.sendChannelMessage(
@@ -616,7 +657,7 @@ class _MessagesTabState extends State<MessagesTab> {
         deliveryStatus: MessageDeliveryStatus.sending,
         recipientPublicKey: isChannel ? null : recipient?.publicKey,
       );
-      messagesProvider.addSentMessage(placeholder);
+      messagesProvider.addSentMessage(placeholder, contact: recipient);
 
       // Send IE1 envelope via normal message path.
       final envelopeText = envelope.encode();
@@ -921,7 +962,7 @@ class _MessagesTabState extends State<MessagesTab> {
       channelIdx: channelIdx,
       recipientPublicKey: isChannel ? null : recipient?.publicKey,
     );
-    messagesProvider.addSentMessage(sentMsg);
+    messagesProvider.addSentMessage(sentMsg, contact: recipient);
 
     try {
       if (isChannel) {
@@ -1327,9 +1368,6 @@ class _MessagesTabState extends State<MessagesTab> {
           // SAR marker data is automatically added by SarMessageParser.enhanceMessage in MessagesProvider
         );
 
-        // Add to messages list with "sending" status
-        messagesProvider.addSentMessage(sentMessage);
-
         // Look up the room contact for path logging
         final contactsProvider = context.read<ContactsProvider>();
         final roomContact = contactsProvider.contacts.where((c) {
@@ -1337,6 +1375,9 @@ class _MessagesTabState extends State<MessagesTab> {
               c.publicKey.matches(roomPublicKey);
         }).firstOrNull;
 
+        // Add to messages list with "sending" status
+        messagesProvider.addSentMessage(sentMessage, contact: roomContact);
+
         // Send SAR message to selected room (persisted and immutable)
         final sentSuccessfully = await connectionProvider.sendTextMessage(
           contactPublicKey: roomPublicKey!,
@@ -1563,12 +1604,6 @@ class _MessagesTabState extends State<MessagesTab> {
             Container(
               decoration: BoxDecoration(
                 color: Theme.of(context).colorScheme.surface,
-                border: Border(
-                  top: BorderSide(
-                    color: Theme.of(context).dividerColor,
-                    width: 1,
-                  ),
-                ),
               ),
               child: Column(
                 mainAxisSize: MainAxisSize.min,
@@ -1576,7 +1611,28 @@ class _MessagesTabState extends State<MessagesTab> {
                   SafeArea(
                     top: false,
                     child: Padding(
-                      padding: const EdgeInsets.fromLTRB(12, 12, 12, 12),
+                      padding: const EdgeInsets.fromLTRB(10, 10, 10, 10),
+                      child: Container(
+                        decoration: BoxDecoration(
+                          color: Theme.of(
+                            context,
+                          ).colorScheme.surfaceContainerLow,
+                          borderRadius: BorderRadius.circular(28),
+                          border: Border.all(
+                            color: Theme.of(
+                              context,
+                            ).dividerColor.withValues(alpha: 0.35),
+                          ),
+                          boxShadow: [
+                            BoxShadow(
+                              color: Colors.black.withValues(alpha: 0.05),
+                              blurRadius: 18,
+                              offset: const Offset(0, 6),
+                            ),
+                          ],
+                        ),
+                        child: Padding(
+                          padding: const EdgeInsets.fromLTRB(10, 10, 10, 8),
                           child: Column(
                             mainAxisSize: MainAxisSize.min,
                             crossAxisAlignment: CrossAxisAlignment.stretch,
@@ -1584,18 +1640,23 @@ class _MessagesTabState extends State<MessagesTab> {
                               Row(
                                 children: [
                                   Container(
-                                width: 46,
+                                    width: 42,
-                                height: 46,
+                                    height: 42,
                                     decoration: BoxDecoration(
-                                  color: Theme.of(context)
+                                      color: Theme.of(
-                                      .colorScheme
+                                        context,
-                                      .primaryContainer
+                                      ).colorScheme.surface,
-                                      .withValues(alpha: 0.95),
                                       shape: BoxShape.circle,
+                                      border: Border.all(
+                                        color: Theme.of(
+                                          context,
+                                        ).dividerColor.withValues(alpha: 0.35),
+                                      ),
                                     ),
                                     child: IconButton(
                                       icon: Icon(
                                         _isRecording ? Icons.stop : Icons.add,
+                                        size: 22,
                                       ),
                                       tooltip: _isRecording
                                           ? 'Stop recording'
@@ -1607,34 +1668,29 @@ class _MessagesTabState extends State<MessagesTab> {
                                           ? Colors.red
                                           : Theme.of(
                                               context,
-                                        ).colorScheme.onPrimaryContainer,
+                                            ).colorScheme.primary,
                                     ),
                                   ),
-                              const SizedBox(width: 10),
+                                  const SizedBox(width: 8),
                                   Expanded(
                                     child: Material(
                                       color: Colors.transparent,
                                       child: InkWell(
-                                    borderRadius: BorderRadius.circular(22),
+                                        borderRadius: BorderRadius.circular(20),
                                         onTap: _showRecipientSelector,
                                         child: Ink(
-                                      height: 46,
+                                          height: 42,
                                           decoration: BoxDecoration(
-                                        color:
-                                            _destinationType ==
-                                                MessageDestinationPreferences
-                                                    .destinationTypeChannel
-                                            ? Theme.of(context)
-                                                  .colorScheme
-                                                  .surfaceContainerHighest
-                                            : Theme.of(
-                                                context,
-                                              ).colorScheme.secondaryContainer,
-                                        borderRadius: BorderRadius.circular(22),
-                                        border: Border.all(
                                             color: Theme.of(
                                               context,
-                                          ).dividerColor.withValues(alpha: 0.7),
+                                            ).colorScheme.surface,
+                                            borderRadius: BorderRadius.circular(
+                                              20,
+                                            ),
+                                            border: Border.all(
+                                              color: Theme.of(context)
+                                                  .dividerColor
+                                                  .withValues(alpha: 0.35),
                                             ),
                                           ),
                                           child: Padding(
@@ -1645,35 +1701,33 @@ class _MessagesTabState extends State<MessagesTab> {
                                               children: [
                                                 Icon(
                                                   _getDestinationIcon(),
-                                              size: 18,
+                                                  size: 17,
+                                                  color: Theme.of(context)
+                                                      .colorScheme
+                                                      .onSurfaceVariant,
                                                 ),
                                                 const SizedBox(width: 10),
                                                 Expanded(
                                                   child: Text(
                                                     _getDestinationLabel(),
-                                                overflow: TextOverflow.ellipsis,
+                                                    overflow:
+                                                        TextOverflow.ellipsis,
                                                     style: TextStyle(
                                                       fontSize: 15,
-                                                  fontWeight: FontWeight.w600,
+                                                      fontWeight:
-                                                  color:
+                                                          FontWeight.w600,
-                                                      _destinationType ==
+                                                      color: Theme.of(
-                                                          MessageDestinationPreferences
-                                                              .destinationTypeChannel
-                                                      ? Theme.of(
                                                         context,
-                                                        ).colorScheme.onSurface
+                                                      ).colorScheme.onSurface,
-                                                      : Theme.of(context)
-                                                            .colorScheme
-                                                            .onSecondaryContainer,
                                                     ),
                                                   ),
                                                 ),
                                                 Icon(
                                                   Icons.expand_more_rounded,
                                                   size: 20,
-                                              color: Theme.of(
+                                                  color: Theme.of(context)
-                                                context,
+                                                      .colorScheme
-                                              ).colorScheme.onSurfaceVariant,
+                                                      .onSurfaceVariant,
                                                 ),
                                               ],
                                             ),
@@ -1684,35 +1738,49 @@ class _MessagesTabState extends State<MessagesTab> {
                                   ),
                                 ],
                               ),
-                          const SizedBox(height: 12),
+                              const SizedBox(height: 8),
                               Row(
                                 crossAxisAlignment: CrossAxisAlignment.center,
                                 children: [
                                   Expanded(
                                     child: AnimatedContainer(
-                                  duration: const Duration(milliseconds: 180),
+                                      duration: const Duration(
+                                        milliseconds: 180,
+                                      ),
                                       constraints: const BoxConstraints(
-                                    minHeight: 48,
+                                        minHeight: 46,
-                                    maxHeight: 140,
+                                        maxHeight: 132,
                                       ),
                                       decoration: BoxDecoration(
                                         color: Theme.of(
                                           context,
-                                    ).colorScheme.surfaceContainerHigh,
+                                        ).colorScheme.surface,
-                                    borderRadius: BorderRadius.circular(28),
+                                        borderRadius: BorderRadius.circular(24),
                                         border: Border.all(
                                           color: _focusNode.hasFocus
                                               ? Theme.of(
                                                   context,
                                                 ).colorScheme.primary
                                               : Theme.of(context).dividerColor
-                                                .withValues(alpha: 0.6),
+                                                    .withValues(alpha: 0.35),
-                                      width: _focusNode.hasFocus ? 1.5 : 1,
+                                          width: _focusNode.hasFocus ? 1.4 : 1,
                                         ),
+                                        boxShadow: _focusNode.hasFocus
+                                            ? [
+                                                BoxShadow(
+                                                  color: Theme.of(context)
+                                                      .colorScheme
+                                                      .primary
+                                                      .withValues(alpha: 0.10),
+                                                  blurRadius: 12,
+                                                  offset: const Offset(0, 4),
+                                                ),
+                                              ]
+                                            : null,
                                       ),
                                       child: Padding(
                                         padding: const EdgeInsets.symmetric(
-                                      horizontal: 18,
+                                          horizontal: 16,
                                           vertical: 12,
                                         ),
                                         child: TextField(
@@ -1722,9 +1790,7 @@ class _MessagesTabState extends State<MessagesTab> {
                                           maxLines: 4,
                                           keyboardType: TextInputType.multiline,
                                           inputFormatters: [
-                                        LengthLimitingTextInputFormatter(
+                                            _messageByteLimiter,
-                                          _maxCharacters,
-                                        ),
                                           ],
                                           style: const TextStyle(fontSize: 15),
                                           textAlignVertical:
@@ -1735,25 +1801,31 @@ class _MessagesTabState extends State<MessagesTab> {
                                             )!.typeYourMessage,
                                             hintStyle: TextStyle(
                                               fontSize: 15,
-                                          color: Theme.of(
+                                              color: Theme.of(context)
-                                            context,
+                                                  .colorScheme
-                                          ).colorScheme.onSurfaceVariant,
+                                                  .onSurfaceVariant
+                                                  .withValues(alpha: 0.9),
                                             ),
+                                            filled: false,
+                                            fillColor: Colors.transparent,
                                             border: InputBorder.none,
                                             isCollapsed: true,
                                           ),
-                                      textInputAction: TextInputAction.newline,
+                                          textInputAction:
+                                              TextInputAction.newline,
                                         ),
                                       ),
                                     ),
                                   ),
-                              const SizedBox(width: 10),
+                                  const SizedBox(width: 8),
                                   Builder(
                                     builder: (context) {
                                       final canSendText =
                                           !_isRecording &&
                                           !_isSendingVoice &&
-                                      _textController.text.trim().isNotEmpty;
+                                          _textController.text
+                                              .trim()
+                                              .isNotEmpty;
                                       final semanticsLabel = _isRecording
                                           ? 'Recording... release to send voice'
                                           : (_isSendingVoice
@@ -1766,11 +1838,15 @@ class _MessagesTabState extends State<MessagesTab> {
                                         button: true,
                                         enabled:
                                             canSendText ||
-                                        (_voiceSupported && !_isSendingVoice),
+                                            (_voiceSupported &&
+                                                !_isSendingVoice),
                                         label: semanticsLabel,
-                                    onTap: canSendText ? _sendMessage : null,
+                                        onTap: canSendText
+                                            ? _sendMessage
+                                            : null,
                                         onLongPress:
-                                        (_voiceSupported && !_isSendingVoice)
+                                            (_voiceSupported &&
+                                                !_isSendingVoice)
                                             ? () {
                                                 if (_isRecording) {
                                                   _stopAndSendVoice();
@@ -1790,11 +1866,13 @@ class _MessagesTabState extends State<MessagesTab> {
                                                 ? (_) => _startVoiceRecording()
                                                 : null,
                                             onLongPressEnd:
-                                            (_voiceSupported && _isRecording)
+                                                (_voiceSupported &&
+                                                    _isRecording)
                                                 ? (_) => _stopAndSendVoice()
                                                 : null,
                                             onLongPressCancel:
-                                            (_voiceSupported && _isRecording)
+                                                (_voiceSupported &&
+                                                    _isRecording)
                                                 ? () => _stopAndSendVoice()
                                                 : null,
                                             child: Column(
@@ -1804,31 +1882,48 @@ class _MessagesTabState extends State<MessagesTab> {
                                                   duration: const Duration(
                                                     milliseconds: 180,
                                                   ),
-                                              width: 48,
+                                                  width: 46,
-                                              height: 48,
+                                                  height: 46,
                                                   decoration: BoxDecoration(
                                                     color:
-                                                    canSendText || _isRecording
+                                                        canSendText ||
+                                                            _isRecording
                                                         ? Theme.of(
                                                             context,
                                                           ).colorScheme.primary
-                                                    : Theme.of(context)
+                                                        : Theme.of(
-                                                          .colorScheme
+                                                            context,
-                                                          .surfaceContainerHighest,
+                                                          ).colorScheme.surface,
                                                     shape: BoxShape.circle,
+                                                    border: Border.all(
+                                                      color:
+                                                          canSendText ||
+                                                              _isRecording
+                                                          ? Colors.transparent
+                                                          : Theme.of(context)
+                                                                .dividerColor
+                                                                .withValues(
+                                                                  alpha: 0.35,
+                                                                ),
+                                                    ),
                                                     boxShadow:
-                                                    canSendText || _isRecording
+                                                        canSendText ||
+                                                            _isRecording
                                                         ? [
                                                             BoxShadow(
                                                               color:
-                                                              Theme.of(context)
+                                                                  Theme.of(
+                                                                        context,
+                                                                      )
                                                                       .colorScheme
                                                                       .primary
                                                                       .withValues(
-                                                                    alpha: 0.28,
+                                                                        alpha:
+                                                                            0.22,
                                                                       ),
-                                                          blurRadius: 16,
+                                                              blurRadius: 14,
-                                                          offset: const Offset(
+                                                              offset:
+                                                                  const Offset(
                                                                     0,
                                                                     6,
                                                                   ),
@@ -1838,8 +1933,7 @@ class _MessagesTabState extends State<MessagesTab> {
                                                   ),
                                                   child: _isSendingVoice
                                                       ? Center(
-                                                      child:
+                                                          child: CircularProgressIndicator(
-                                                          CircularProgressIndicator(
                                                             strokeWidth: 2,
                                                             color:
                                                                 Theme.of(
@@ -1851,32 +1945,43 @@ class _MessagesTabState extends State<MessagesTab> {
                                                         )
                                                       : Icon(
                                                           _isRecording
-                                                          ? Icons.mic_rounded
+                                                              ? Icons
-                                                          : Icons.send_rounded,
+                                                                    .mic_rounded
+                                                              : Icons
+                                                                    .send_rounded,
+                                                          size: 22,
                                                           color:
                                                               canSendText ||
                                                                   _isRecording
-                                                          ? Theme.of(context)
+                                                              ? Theme.of(
+                                                                      context,
+                                                                    )
                                                                     .colorScheme
                                                                     .onPrimary
-                                                          : Theme.of(context)
+                                                              : Theme.of(
+                                                                      context,
+                                                                    )
                                                                     .colorScheme
                                                                     .onSurfaceVariant,
                                                         ),
                                                 ),
-                                            const SizedBox(height: 6),
+                                                const SizedBox(height: 4),
                                                 Text(
-                                              '$_characterCount/$_maxCharacters',
+                                                  '$_messageByteCount/$_maxMessageBytes',
                                                   style: TextStyle(
-                                                fontSize: 12,
+                                                    fontSize: 11,
-                                                fontWeight: FontWeight.w600,
+                                                    fontWeight: FontWeight.w500,
                                                     color:
-                                                    _characterCount >
+                                                        _messageByteCount >
-                                                        _maxCharacters * 0.9
+                                                            _maxMessageBytes *
+                                                                0.9
                                                         ? Colors.orange.shade800
                                                         : Theme.of(context)
                                                               .colorScheme
-                                                          .onSurfaceVariant,
+                                                              .onSurfaceVariant
+                                                              .withValues(
+                                                                alpha: 0.9,
+                                                              ),
                                                   ),
                                                 ),
                                               ],
@@ -1892,6 +1997,8 @@ class _MessagesTabState extends State<MessagesTab> {
                           ),
                         ),
                       ),
+                    ),
+                  ),
                 ],
               ),
             ),

lib/utils/message_extensions.dart

@@ -24,6 +24,9 @@ extension MessageLocalization on Message {
 
     switch (deliveryStatus) {
       case MessageDeliveryStatus.sending:
+        if (isContactMessage) {
+          return l10n.pending;
+        }
         return l10n.sending;
       case MessageDeliveryStatus.sent:
         return l10n.sent;

lib/widgets/map/drawing_toolbar.dart

@@ -849,6 +849,7 @@ class DrawingToolbar extends StatelessWidget {
           contactPublicKey: room.publicKey,
           text: message,
           messageId: messageId,
+          contact: room,
         );
         debugPrint('  ✅ Sent successfully');
 

lib/widgets/messages/message_bubble.dart

@@ -118,7 +118,26 @@ class _MessageBubbleState extends State<MessageBubble> {
       );
 
       // Add retry message to provider
-      messagesProvider.addSentMessage(retryMessage);
+      Contact? roomContact;
+      if (failedMessage.messageType == MessageType.contact) {
+        if (failedMessage.recipientPublicKey == null) {
+          messagesProvider.markMessageFailed(retryMessageId);
+          ToastLogger.error(
+            context,
+            AppLocalizations.of(context)!.cannotRetryMissingRecipient,
+          );
+          return;
+        }
+
+        final contactsProvider = context.read<ContactsProvider>();
+        roomContact = contactsProvider.contacts.where((c) {
+          return c.publicKey.length >=
+                  failedMessage.recipientPublicKey!.length &&
+              c.publicKey.matches(failedMessage.recipientPublicKey!);
+        }).firstOrNull;
+      }
+
+      messagesProvider.addSentMessage(retryMessage, contact: roomContact);
 
       // Resend the message
       if (failedMessage.messageType == MessageType.contact) {
@@ -132,14 +151,6 @@ class _MessageBubbleState extends State<MessageBubble> {
           return;
         }
 
-        // Look up the room contact for path logging
-        final contactsProvider = context.read<ContactsProvider>();
-        final roomContact = contactsProvider.contacts.where((c) {
-          return c.publicKey.length >=
-                  failedMessage.recipientPublicKey!.length &&
-              c.publicKey.matches(failedMessage.recipientPublicKey!);
-        }).firstOrNull;
-
         // Resend to the same room
         final sentSuccessfully = await connectionProvider.sendTextMessage(
           contactPublicKey: failedMessage.recipientPublicKey!,
@@ -1805,7 +1816,7 @@ class _MessageBubbleState extends State<MessageBubble> {
         ? '${l10n.channel}: $channelDisplayName'
         : null;
 
-    final shouldFloatBubble = message.isChannelMessage || widget.isCompact;
+    final shouldFloatBubble = widget.isCompact;
     final bubble = ConstrainedBox(
       constraints: BoxConstraints(
         maxWidth: shouldFloatBubble
@@ -1946,7 +1957,11 @@ class _MessageBubbleState extends State<MessageBubble> {
                         child: Row(
                           mainAxisSize: MainAxisSize.min,
                           children: [
-                          const Icon(Icons.draw, size: 16, color: Colors.white),
+                            const Icon(
+                              Icons.draw,
+                              size: 16,
+                              color: Colors.white,
+                            ),
                             const SizedBox(width: 4),
                             Text(
                               AppLocalizations.of(context)!.mapDrawing,
@@ -2075,7 +2090,9 @@ class _MessageBubbleState extends State<MessageBubble> {
                       ),
                       const SizedBox(width: 2),
                       Text(
-                      message.pathLen == 0 ? 'direct' : '${message.pathLen}hop',
+                        message.pathLen == 0
+                            ? 'direct'
+                            : '${message.pathLen}hop',
                         style: Theme.of(context).textTheme.labelSmall?.copyWith(
                           color: Theme.of(
                             context,
@@ -2101,7 +2118,8 @@ class _MessageBubbleState extends State<MessageBubble> {
                     Row(
                       children: [
                         Text(
-                        message.sarCustomEmoji ?? message.sarMarkerType!.emoji,
+                          message.sarCustomEmoji ??
+                              message.sarMarkerType!.emoji,
                           style: const TextStyle(fontSize: 32),
                         ),
                         const SizedBox(width: 10),
@@ -2129,9 +2147,8 @@ class _MessageBubbleState extends State<MessageBubble> {
                       const SizedBox(height: 6),
                       Text(
                         '${message.sarGpsCoordinates!.latitude.toStringAsFixed(5)}, ${message.sarGpsCoordinates!.longitude.toStringAsFixed(5)}',
-                      style: Theme.of(context).textTheme.labelMedium?.copyWith(
+                        style: Theme.of(context).textTheme.labelMedium
-                        fontFamily: 'monospace',
+                            ?.copyWith(fontFamily: 'monospace'),
-                      ),
                       ),
                     ],
                   ],
@@ -2201,7 +2218,9 @@ class _MessageBubbleState extends State<MessageBubble> {
                                   const SizedBox(width: 6),
                                   Text(
                                     colorName,
-                                  style: Theme.of(context).textTheme.labelSmall,
+                                    style: Theme.of(
+                                      context,
+                                    ).textTheme.labelSmall,
                                   ),
                                 ],
                               ),
@@ -2229,10 +2248,16 @@ class _MessageBubbleState extends State<MessageBubble> {
               // Tic-Tac-Toe control message content
               else if (ticTacToeEvent?.type == TicTacToeEventType.start &&
                   !widget.isCompact)
-              TicTacToeMessageBubble(message: message, isSentByMe: isOwnMessage)
+                TicTacToeMessageBubble(
+                  message: message,
+                  isSentByMe: isOwnMessage,
+                )
               // Regular message content
               else if (!message.isDrawing || widget.isCompact)
-              Text(message.text, style: Theme.of(context).textTheme.bodyMedium),
+                Text(
+                  message.text,
+                  style: Theme.of(context).textTheme.bodyMedium,
+                ),
 
               if (!widget.isCompact &&
                   !isSarMarker &&
@@ -2319,7 +2344,9 @@ class _MessageBubbleState extends State<MessageBubble> {
                             ),
                             const SizedBox(width: 4),
                             Icon(
-                            _isExpanded ? Icons.expand_less : Icons.expand_more,
+                              _isExpanded
+                                  ? Icons.expand_less
+                                  : Icons.expand_more,
                               size: 14,
                               color: Theme.of(
                                 context,
@@ -2343,7 +2370,9 @@ class _MessageBubbleState extends State<MessageBubble> {
                               crossAxisAlignment: CrossAxisAlignment.start,
                               children: [
                                 Text(
-                                AppLocalizations.of(context)!.recipientDetails,
+                                  AppLocalizations.of(
+                                    context,
+                                  )!.recipientDetails,
                                   style: Theme.of(context).textTheme.labelSmall
                                       ?.copyWith(fontWeight: FontWeight.bold),
                                 ),
@@ -2469,7 +2498,10 @@ class _MessageBubbleState extends State<MessageBubble> {
                             decoration: BoxDecoration(
                               color: Colors.orange.withValues(alpha: 0.2),
                               borderRadius: BorderRadius.circular(4),
-                            border: Border.all(color: Colors.orange, width: 1),
+                              border: Border.all(
+                                color: Colors.orange,
+                                width: 1,
+                              ),
                             ),
                             child: Row(
                               mainAxisSize: MainAxisSize.min,

lib/widgets/messages/tictactoe_message_bubble.dart

@@ -97,9 +97,7 @@ class TicTacToeMessageBubble extends StatelessWidget {
         children: [
           Text(
             'Tic-Tac-Toe · Game ${state.gameId}',
-            style: Theme.of(
+            style: Theme.of(context).textTheme.labelMedium?.copyWith(
-              context,
-            ).textTheme.labelMedium?.copyWith(
               fontWeight: FontWeight.bold,
               color: titleColor,
             ),
@@ -167,7 +165,7 @@ class TicTacToeMessageBubble extends StatelessWidget {
       deliveryStatus: MessageDeliveryStatus.sending,
       recipientPublicKey: opponent.publicKey,
     );
-    messagesProvider.addSentMessage(sentMessage);
+    messagesProvider.addSentMessage(sentMessage, contact: opponent);
 
     final sent = await connectionProvider.sendTextMessage(
       contactPublicKey: opponent.publicKey,

pubspec.lock

@@ -235,7 +235,7 @@ packages:
     source: hosted
     version: "3.3.0"
   fake_async:
-    dependency: transitive
+    dependency: "direct dev"
     description:
       name: fake_async
       sha256: "5368f224a74523e8d2e7399ea1638b37aecfca824a3cc4dfdf77bf1fa905ac44"

pubspec.yaml

@@ -144,6 +144,7 @@ dev_dependencies:
   # rules and activating additional ones.
   flutter_lints: ^6.0.0
   flutter_launcher_icons: "^0.14.4"
+  fake_async: ^1.3.3
 
 dependency_overrides:
   meshcore_client:

test/providers/helpers/message_delivery_tracker_test.dart

@@ -0,0 +1,37 @@
+import 'dart:typed_data';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:meshcore_sar_app/providers/helpers/message_delivery_tracker.dart';
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  group('MessageDeliveryTracker', () {
+    test('matches pending direct messages by contact', () {
+      final tracker = MessageDeliveryTracker();
+      final alice = Uint8List.fromList(List<int>.filled(32, 0xAA));
+      final bob = Uint8List.fromList(List<int>.filled(32, 0xBB));
+
+      tracker.trackPendingDirectMessage('alice-1', alice);
+      tracker.trackPendingDirectMessage('bob-1', bob);
+      tracker.trackPendingDirectMessage('alice-2', alice);
+
+      expect(tracker.popPendingDirectMessageId(alice), 'alice-1');
+      expect(tracker.popPendingDirectMessageId(bob), 'bob-1');
+      expect(tracker.popPendingDirectMessageId(alice), 'alice-2');
+    });
+
+    test('removeByMessageId clears pending queue state', () {
+      final tracker = MessageDeliveryTracker();
+      final alice = Uint8List.fromList(List<int>.filled(32, 0xAA));
+
+      tracker.trackPendingDirectMessage('alice-1', alice);
+      tracker.mapAckTagToMessageId(42, 'alice-1');
+
+      tracker.removeByMessageId('alice-1');
+
+      expect(tracker.getMessageIdForAck(42), isNull);
+      expect(tracker.popPendingDirectMessageId(alice), isNull);
+    });
+  });
+}

test/providers/messages_provider_retransmission_test.dart

@@ -0,0 +1,131 @@
+import 'dart:typed_data';
+
+import 'package:fake_async/fake_async.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:meshcore_sar_app/models/contact.dart';
+import 'package:meshcore_sar_app/models/message.dart';
+import 'package:meshcore_sar_app/providers/messages_provider.dart';
+
+Contact _buildContact() {
+  return Contact(
+    publicKey: Uint8List.fromList(List<int>.generate(32, (i) => i)),
+    type: ContactType.chat,
+    flags: 0,
+    outPathLen: 1,
+    outPath: Uint8List.fromList([1, 2, 3, 4]),
+    advName: 'Teammate',
+    lastAdvert: 1700000000,
+    advLat: 0,
+    advLon: 0,
+    lastMod: 1700000000,
+  );
+}
+
+Message _buildDirectMessage(String id) {
+  return Message(
+    id: id,
+    messageType: MessageType.contact,
+    senderPublicKeyPrefix: Uint8List.fromList([0, 1, 2, 3, 4, 5]),
+    pathLen: 0,
+    textType: MessageTextType.plain,
+    senderTimestamp: 1700000000,
+    text: 'hello',
+    receivedAt: DateTime.now(),
+    deliveryStatus: MessageDeliveryStatus.sending,
+    recipientPublicKey: Uint8List.fromList(List<int>.generate(32, (i) => i)),
+  );
+}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  group('MessagesProvider retransmission', () {
+    test('direct messages stay pending until delivery ACK arrives', () {
+      final provider = MessagesProvider();
+      provider.addSentMessage(
+        _buildDirectMessage('m1'),
+        contact: _buildContact(),
+      );
+
+      provider.markMessageSent('m1', 77, 250);
+
+      expect(
+        provider.messages.single.deliveryStatus,
+        MessageDeliveryStatus.sending,
+      );
+      expect(provider.messages.single.expectedAckTag, 77);
+
+      provider.markMessageDelivered(77, 180);
+
+      expect(
+        provider.messages.single.deliveryStatus,
+        MessageDeliveryStatus.delivered,
+      );
+      expect(provider.messages.single.roundTripTimeMs, 180);
+    });
+
+    test('channel messages are marked sent immediately', () {
+      final provider = MessagesProvider();
+      provider.addSentMessage(
+        Message(
+          id: 'c1',
+          messageType: MessageType.channel,
+          senderPublicKeyPrefix: Uint8List.fromList([0, 1, 2, 3, 4, 5]),
+          channelIdx: 0,
+          pathLen: 0,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000000,
+          text: 'broadcast',
+          receivedAt: DateTime.now(),
+          deliveryStatus: MessageDeliveryStatus.sending,
+        ),
+      );
+
+      provider.markMessageSent('c1', 0, 0);
+
+      expect(
+        provider.messages.single.deliveryStatus,
+        MessageDeliveryStatus.sent,
+      );
+    });
+
+    test('missing ACK schedules a delayed retransmission', () {
+      fakeAsync((async) {
+        final provider = MessagesProvider();
+        var retryCalls = 0;
+        provider.sendMessageCallback =
+            ({
+              required contactPublicKey,
+              required text,
+              required messageId,
+              required contact,
+              retryAttempt = 0,
+            }) async {
+              retryCalls += 1;
+              return true;
+            };
+
+        provider.addSentMessage(
+          _buildDirectMessage('m2'),
+          contact: _buildContact(),
+        );
+        provider.markMessageSent('m2', 88, 10);
+
+        async.elapse(const Duration(milliseconds: 11));
+        async.flushMicrotasks();
+
+        expect(provider.messages.single.retryAttempt, 1);
+        expect(
+          provider.messages.single.deliveryStatus,
+          MessageDeliveryStatus.sending,
+        );
+        expect(retryCalls, 0);
+
+        async.elapse(const Duration(seconds: 4));
+        async.flushMicrotasks();
+
+        expect(retryCalls, 1);
+      });
+    });
+  });
+}