remove voice code make optimizations. Fix channels race conditions. add reply function

lib/connector/meshcore_connector.dart

@@ -21,7 +21,6 @@ import '../services/path_history_service.dart';
 import '../services/app_settings_service.dart';
 import '../services/background_service.dart';
 import '../services/notification_service.dart';
-import '../services/voice_message_service.dart';
 import '../storage/channel_message_store.dart';
 import '../storage/channel_order_store.dart';
 import '../storage/channel_settings_store.dart';
@@ -46,6 +45,9 @@ enum MeshCoreConnectionState {
 }
 
 class MeshCoreConnector extends ChangeNotifier {
+  // Message windowing to limit memory usage
+  static const int _messageWindowSize = 200;
+
   MeshCoreConnectionState _state = MeshCoreConnectionState.disconnected;
   BluetoothDevice? _device;
   BluetoothCharacteristic? _rxCharacteristic;
@@ -113,9 +115,6 @@ class MeshCoreConnector extends ChangeNotifier {
   final ContactSettingsStore _contactSettingsStore = ContactSettingsStore();
   final ContactStore _contactStore = ContactStore();
   final UnreadStore _unreadStore = UnreadStore();
-  final VoiceMessageService _voiceMessageService = VoiceMessageService.instance;
-  final Map<String, _VoiceAssembly> _voiceAssemblies = {};
-  _VoiceSendSession? _voiceSendSession;
   final Map<int, bool> _channelSmazEnabled = {};
   final Map<String, bool> _contactSmazEnabled = {};
   final Set<String> _knownContactKeys = {};
@@ -124,23 +123,13 @@ class MeshCoreConnector extends ChangeNotifier {
   String? _activeContactKey;
   int? _activeChannelIndex;
   List<int> _channelOrder = [];
-  int _lastVoiceTimestampSeconds = 0;
 
   // Getters
   MeshCoreConnectionState get state => _state;
   BluetoothDevice? get device => _device;
   String? get deviceId => _deviceId;
   String get deviceIdLabel => _deviceId ?? 'Unknown';
-  bool get isVoiceSending => _voiceSendSession != null;
 
-  void cancelVoiceSend() {
-    final session = _voiceSendSession;
-    if (session == null) return;
-    session.cancel();
-    _voiceSendSession = null;
-    _updateVoiceMessageStatus(session.messageId, MessageStatus.failed);
-    notifyListeners();
-  }
   String get deviceDisplayName {
     if (_selfName != null && _selfName!.isNotEmpty) {
       return _selfName!;
@@ -227,12 +216,6 @@ class MeshCoreConnector extends ChangeNotifier {
     if (messages == null) return;
     final removed = messages.remove(message);
     if (!removed) return;
-    if (message.isVoice && message.voicePath != null) {
-      final file = File(message.voicePath!);
-      if (await file.exists()) {
-        await file.delete();
-      }
-    }
     await _messageStore.saveMessages(contactKeyHex, messages);
     notifyListeners();
   }
@@ -241,13 +224,43 @@ class MeshCoreConnector extends ChangeNotifier {
     if (_loadedConversationKeys.contains(contactKeyHex)) return;
     _loadedConversationKeys.add(contactKeyHex);
 
-    final messages = await _messageStore.loadMessages(contactKeyHex);
-    if (messages.isNotEmpty) {
-      _conversations[contactKeyHex] = messages;
+    final allMessages = await _messageStore.loadMessages(contactKeyHex);
+    if (allMessages.isNotEmpty) {
+      // Keep only the most recent N messages in memory to bound memory usage
+      final windowedMessages = allMessages.length > _messageWindowSize
+          ? allMessages.sublist(allMessages.length - _messageWindowSize)
+          : allMessages;
+
+      _conversations[contactKeyHex] = windowedMessages;
       notifyListeners();
     }
   }
 
+  /// Load older messages for a contact (pagination)
+  Future<List<Message>> loadOlderMessages(
+    String contactKeyHex, {
+    int count = 50,
+  }) async {
+    final allMessages = await _messageStore.loadMessages(contactKeyHex);
+    final currentMessages = _conversations[contactKeyHex] ?? [];
+
+    if (allMessages.length <= currentMessages.length) {
+      return []; // No more messages to load
+    }
+
+    final currentOffset = allMessages.length - currentMessages.length;
+    final fetchCount = count.clamp(0, currentOffset);
+    final startIndex = currentOffset - fetchCount;
+
+    final olderMessages = allMessages.sublist(startIndex, currentOffset);
+
+    // Prepend to current conversation
+    _conversations[contactKeyHex] = [...olderMessages, ...currentMessages];
+    notifyListeners();
+
+    return olderMessages;
+  }
+
   List<ChannelMessage> getChannelMessages(Channel channel) {
     return _channelMessages[channel.index] ?? [];
   }
@@ -376,13 +389,43 @@ class MeshCoreConnector extends ChangeNotifier {
 
   /// Load persisted channel messages for a specific channel
   Future<void> _loadChannelMessages(int channelIndex) async {
-    final messages = await _channelMessageStore.loadChannelMessages(channelIndex);
-    if (messages.isNotEmpty) {
-      _channelMessages[channelIndex] = messages;
+    final allMessages = await _channelMessageStore.loadChannelMessages(channelIndex);
+    if (allMessages.isNotEmpty) {
+      // Keep only the most recent N messages in memory to bound memory usage
+      final windowedMessages = allMessages.length > _messageWindowSize
+          ? allMessages.sublist(allMessages.length - _messageWindowSize)
+          : allMessages;
+
+      _channelMessages[channelIndex] = windowedMessages;
       notifyListeners();
     }
   }
 
+  /// Load older channel messages (pagination)
+  Future<List<ChannelMessage>> loadOlderChannelMessages(
+    int channelIndex, {
+    int count = 50,
+  }) async {
+    final allMessages = await _channelMessageStore.loadChannelMessages(channelIndex);
+    final currentMessages = _channelMessages[channelIndex] ?? [];
+
+    if (allMessages.length <= currentMessages.length) {
+      return []; // No more messages to load
+    }
+
+    final currentOffset = allMessages.length - currentMessages.length;
+    final fetchCount = count.clamp(0, currentOffset);
+    final startIndex = currentOffset - fetchCount;
+
+    final olderMessages = allMessages.sublist(startIndex, currentOffset);
+
+    // Prepend to current conversation
+    _channelMessages[channelIndex] = [...olderMessages, ...currentMessages];
+    notifyListeners();
+
+    return olderMessages;
+  }
+
   /// Load all persisted channel messages on startup
   Future<void> loadAllChannelMessages({int? maxChannels}) async {
     final channelCount = maxChannels ?? _maxChannels;
@@ -876,16 +919,10 @@ class MeshCoreConnector extends ChangeNotifier {
     int? customPathLen,
   }) async {
     if (!isConnected || text.isEmpty) return;
-    if (_voiceSendSession != null) {
-      debugPrint('Voice send in progress, skipping text send.');
-      return;
-    }
 
     // If custom path is provided, temporarily update the contact's path
     if (customPath != null && customPathLen != null && customPathLen >= 0) {
       await setContactPath(contact, customPath, customPathLen);
-      // Small delay to ensure the path update is processed
-      await Future.delayed(const Duration(milliseconds: 50));
     }
 
     PathSelection? autoSelection;
@@ -901,7 +938,6 @@ class MeshCoreConnector extends ChangeNotifier {
             Uint8List.fromList(autoSelection.pathBytes),
             autoSelection.pathBytes.length,
           );
-          await Future.delayed(const Duration(milliseconds: 50));
         }
       }
     }
@@ -943,143 +979,11 @@ class MeshCoreConnector extends ChangeNotifier {
     }
   }
 
-  Future<void> sendVoiceMessage({
-    required Contact contact,
-    required Uint8List codec2Bytes,
-    required String voicePath,
-    required int durationMs,
-    int? timestampSeconds,
-  }) async {
-    if (!isConnected || codec2Bytes.isEmpty) return;
-    if (_voiceSendSession != null) return;
-
-    final voiceTimestampSeconds = timestampSeconds ?? _nextVoiceTimestampSeconds();
-    final chunks = _voiceMessageService.buildVoiceChunks(codec2Bytes);
-    if (chunks.isEmpty) return;
-
-    final messageId = const Uuid().v4();
-    final message = Message(
-      senderKey: contact.publicKey,
-      text: 'Voice message',
-      timestamp: DateTime.fromMillisecondsSinceEpoch(voiceTimestampSeconds * 1000),
-      isOutgoing: true,
-      isCli: false,
-      status: MessageStatus.pending,
-      messageId: messageId,
-      forceFlood: false,
-      isVoice: true,
-      voicePath: voicePath,
-      voiceDurationMs: durationMs,
-      voiceCodec: VoiceMessageService.codecName,
-    );
-
-    _addMessage(contact.publicKeyHex, message);
-    notifyListeners();
-
-    final session = _VoiceSendSession(
-      contact: contact,
-      messageId: messageId,
-      chunks: chunks,
-      timestampSeconds: voiceTimestampSeconds,
-    );
-    _voiceSendSession = session;
-    notifyListeners();
-
-    unawaited(_sendVoiceChunks(session));
-  }
-
-  int reserveVoiceTimestampSeconds() {
-    return _nextVoiceTimestampSeconds();
-  }
-
-  int _nextVoiceTimestampSeconds() {
-    final nowSeconds = DateTime.now().millisecondsSinceEpoch ~/ 1000;
-    if (nowSeconds <= _lastVoiceTimestampSeconds) {
-      _lastVoiceTimestampSeconds += 1;
-    } else {
-      _lastVoiceTimestampSeconds = nowSeconds;
-    }
-    return _lastVoiceTimestampSeconds;
-  }
-
-  Future<void> _sendVoiceChunks(_VoiceSendSession session) async {
-    for (var i = 0; i < session.chunks.length; i++) {
-      if (session.isCancelled) return;
-      final ok = await _sendVoiceChunk(session, i);
-      if (!ok) {
-        if (session.isCancelled) return;
-        _updateVoiceMessageStatus(session.messageId, MessageStatus.failed);
-        _voiceSendSession = null;
-        notifyListeners();
-        return;
-      }
-    }
-    if (session.isCancelled) return;
-    _updateVoiceMessageStatus(session.messageId, MessageStatus.delivered);
-    _voiceSendSession = null;
-    notifyListeners();
-  }
-
-  Future<bool> _sendVoiceChunk(_VoiceSendSession session, int index) async {
-    if (session.isCancelled) return false;
-    session.beginChunk(index);
-    await sendFrame(
-      buildSendTextMsgFrame(
-        session.contact.publicKey,
-        session.chunks[index],
-        forceFlood: false,
-        attempt: 0,
-        timestampSeconds: session.timestampSeconds,
-      ),
-    );
-
-    try {
-      await session.sentCompleter!.future.timeout(const Duration(seconds: 10));
-    } catch (_) {
-      return false;
-    }
-
-    final timeoutMs = session.expectedTimeoutMs;
-    final confirmTimeout = timeoutMs != null && timeoutMs > 0
-        ? Duration(milliseconds: timeoutMs)
-        : const Duration(seconds: 30);
-
-    try {
-      await session.confirmCompleter!.future.timeout(confirmTimeout);
-    } catch (_) {
-      return false;
-    }
-    return true;
-  }
-
-  void _updateVoiceMessageStatus(String messageId, MessageStatus status) {
-    for (final entry in _conversations.entries) {
-      final messages = entry.value;
-      final index = messages.indexWhere((m) => m.messageId == messageId);
-      if (index == -1) continue;
-      messages[index] = messages[index].copyWith(status: status);
-      _messageStore.saveMessages(entry.key, messages);
-      break;
-    }
-  }
-
-  void _handleVoiceMessageSent(Uint8List ackHash, int timeoutMs, {required bool isFlood}) {
-    final session = _voiceSendSession;
-    if (session == null) return;
-    session.handleSent(ackHash, timeoutMs);
-    if (isFlood) {
-      // Flooded sends may not emit send-confirmed; unblock voice chunking.
-      session.handleConfirmed(ackHash);
-    }
-  }
-
-  void _handleVoiceSendConfirmed(Uint8List ackHash) {
-    final session = _voiceSendSession;
-    if (session == null) return;
-    session.handleConfirmed(ackHash);
-  }
-
-  Future<void> setContactPath(Contact contact, Uint8List customPath, int pathLen) async {
+  Future<void> setContactPath(
+    Contact contact,
+    Uint8List customPath,
+    int pathLen,
+  ) async {
     if (!isConnected) return;
 
     await sendFrame(buildUpdateContactPathFrame(
@@ -1091,12 +995,8 @@ class MeshCoreConnector extends ChangeNotifier {
     ));
   }
 
-  Future<void> sendChannelMessage(Channel channel, String text) async {
+  Future<void> sendChannelMessage(Channel channel, String text) async{
     if (!isConnected || text.isEmpty) return;
-    if (_voiceSendSession != null) {
-      debugPrint('Voice send in progress, skipping channel send.');
-      return;
-    }
 
     final message = ChannelMessage.outgoing(text, _selfName ?? 'Me', channel.index);
     _addChannelMessage(channel.index, message);
@@ -1120,9 +1020,9 @@ class MeshCoreConnector extends ChangeNotifier {
     _conversations.remove(contact.publicKeyHex);
     _loadedConversationKeys.remove(contact.publicKeyHex);
     _contactLastReadMs.remove(contact.publicKeyHex);
-    unawaited(_unreadStore.saveContactLastRead(
+    _unreadStore.saveContactLastRead(
       Map<String, int>.from(_contactLastReadMs),
-    ));
+    );
     _messageStore.clearMessages(contact.publicKeyHex);
     notifyListeners();
   }
@@ -1250,9 +1150,9 @@ class MeshCoreConnector extends ChangeNotifier {
     // Delete by setting empty name and zero PSK
     await sendFrame(buildSetChannelFrame(index, '', Uint8List(16)));
     _channelLastReadMs.remove(index);
-    unawaited(_unreadStore.saveChannelLastRead(
+    _unreadStore.saveChannelLastRead(
       Map<int, int>.from(_channelLastReadMs),
-    ));
+    );
     // Refresh channels after deleting
     await getChannels();
   }
@@ -1505,9 +1405,9 @@ class MeshCoreConnector extends ChangeNotifier {
     if (contact != null) {
       if (contact.type == advTypeRepeater) {
         _contactLastReadMs.remove(contact.publicKeyHex);
-        unawaited(_unreadStore.saveContactLastRead(
+        _unreadStore.saveContactLastRead(
           Map<String, int>.from(_contactLastReadMs),
-        ));
+        );
       }
       // Check if this is a new contact
       final isNewContact = !_knownContactKeys.contains(contact.publicKeyHex);
@@ -1656,9 +1556,6 @@ class MeshCoreConnector extends ChangeNotifier {
           pathBytes: contact.pathLength < 0 ? Uint8List(0) : contact.path,
         );
       }
-      if (_tryHandleVoiceChunk(message)) {
-        return;
-      }
       if (contact != null) {
         _updateContactLastMessageAt(contact.publicKeyHex, message.timestamp);
       }
@@ -1784,124 +1681,9 @@ class MeshCoreConnector extends ChangeNotifier {
     return text;
   }
 
-  bool _tryHandleVoiceChunk(Message message) {
-    if (message.isOutgoing || message.isCli) return false;
-    final chunk = _voiceMessageService.tryParseChunk(message.text);
-    if (chunk == null) return false;
-    _updateContactLastMessageAt(
-      message.senderKeyHex,
-      message.timestamp,
-      notify: true,
-    );
-    final timestampSeconds = message.timestamp.millisecondsSinceEpoch ~/ 1000;
-    final key = _voiceAssemblyKey(message.senderKeyHex, timestampSeconds);
-    final assembly = _voiceAssemblies.putIfAbsent(
-      key,
-      () => _VoiceAssembly(
-        senderKey: message.senderKey,
-        senderKeyHex: message.senderKeyHex,
-        timestampSeconds: timestampSeconds,
-        totalChunks: chunk.count,
-      ),
-    );
-    if (assembly.totalChunks != chunk.count) {
-      _voiceAssemblies.remove(key);
-      return true;
-    }
-    assembly.addChunk(chunk);
-    if (assembly.isComplete) {
-      _voiceAssemblies.remove(key);
-      unawaited(_finalizeVoiceAssembly(assembly, message));
-    }
-    _cleanupVoiceAssemblies();
-    if (_isSyncingQueuedMessages) {
-      _handleQueuedMessageReceived();
-    }
-    return true;
-  }
 
-  String _voiceAssemblyKey(String senderKeyHex, int timestampSeconds) {
-    return '$senderKeyHex:$timestampSeconds';
-  }
 
-  Future<void> _finalizeVoiceAssembly(_VoiceAssembly assembly, Message chunkMessage) async {
-    final codec2Bytes = assembly.assemble();
-    if (codec2Bytes.isEmpty) return;
-    final existing = _conversations[assembly.senderKeyHex];
-    if (existing != null) {
-      final alreadyAdded = existing.any((message) {
-        if (!message.isVoice) return false;
-        final tsSeconds = message.timestamp.millisecondsSinceEpoch ~/ 1000;
-        return tsSeconds == assembly.timestampSeconds;
-      });
-      if (alreadyAdded) return;
-    }
-    String? filePath;
-    int durationMs = 0;
-    try {
-      final pcmBytes = _voiceMessageService.decodeCodec2ToPcm(codec2Bytes);
-      durationMs = _voiceMessageService.durationMsForCodec2Bytes(codec2Bytes);
-      final fileName = _voiceMessageService.buildVoiceFileName(
-        senderKeyHex: assembly.senderKeyHex,
-        timestampSeconds: assembly.timestampSeconds,
-      );
-      filePath = await _voiceMessageService.writeWavFile(
-        pcmBytes: pcmBytes,
-        fileName: fileName,
-      );
-    } catch (e) {
-      debugPrint('Voice decode failed: $e');
-      return;
-    }
 
-    final message = Message(
-      senderKey: assembly.senderKey,
-      text: 'Voice message',
-      timestamp: DateTime.fromMillisecondsSinceEpoch(assembly.timestampSeconds * 1000),
-      isOutgoing: false,
-      isCli: false,
-      status: MessageStatus.delivered,
-      isVoice: true,
-      voicePath: filePath,
-      voiceDurationMs: durationMs,
-      voiceCodec: VoiceMessageService.codecName,
-      pathLength: chunkMessage.pathLength,
-      pathBytes: chunkMessage.pathBytes,
-    );
-
-    _addMessage(assembly.senderKeyHex, message);
-    _maybeMarkActiveContactRead(message);
-    notifyListeners();
-
-    if (_appSettingsService != null) {
-      final settings = _appSettingsService!.settings;
-      if (settings.notificationsEnabled && settings.notifyOnNewMessage) {
-        final contact = _contacts.cast<Contact?>().firstWhere(
-          (c) => c != null && c.publicKeyHex == assembly.senderKeyHex,
-          orElse: () => null,
-        );
-        _notificationService.showMessageNotification(
-          contactName: contact?.name ?? 'Unknown',
-          message: 'Voice message',
-          contactId: assembly.senderKeyHex,
-        );
-      }
-    }
-  }
-
-  void _cleanupVoiceAssemblies() {
-    if (_voiceAssemblies.isEmpty) return;
-    final cutoff = DateTime.now().subtract(const Duration(minutes: 3));
-    final expiredKeys = <String>[];
-    for (final entry in _voiceAssemblies.entries) {
-      if (entry.value.startedAt.isBefore(cutoff)) {
-        expiredKeys.add(entry.key);
-      }
-    }
-    for (final key in expiredKeys) {
-      _voiceAssemblies.remove(key);
-    }
-  }
 
   String _channelDisplayName(int channelIndex) {
     for (final channel in _channels) {
@@ -2030,7 +1812,6 @@ class MeshCoreConnector extends ChangeNotifier {
       if (_retryService != null) {
         _retryService!.updateMessageFromSent(ackHash, timeoutMs);
       }
-      _handleVoiceMessageSent(ackHash, timeoutMs, isFlood: isFlood);
     } else {
       // Fallback to old behavior
       for (var messages in _conversations.values) {
@@ -2059,7 +1840,6 @@ class MeshCoreConnector extends ChangeNotifier {
       if (_retryService != null) {
         _retryService!.handleAckReceived(ackHash, tripTimeMs);
       }
-      _handleVoiceSendConfirmed(ackHash);
     } else {
       // Fallback to old behavior
       for (var messages in _conversations.values) {
@@ -2138,9 +1918,9 @@ class MeshCoreConnector extends ChangeNotifier {
     final existing = _contactLastReadMs[contactKeyHex] ?? 0;
     if (timestampMs <= existing) return;
     _contactLastReadMs[contactKeyHex] = timestampMs;
-    unawaited(_unreadStore.saveContactLastRead(
+    _unreadStore.saveContactLastRead(
       Map<String, int>.from(_contactLastReadMs),
-    ));
+    );
     if (notify) {
       notifyListeners();
     }
@@ -2150,9 +1930,9 @@ class MeshCoreConnector extends ChangeNotifier {
     final existing = _channelLastReadMs[channelIndex] ?? 0;
     if (timestampMs <= existing) return;
     _channelLastReadMs[channelIndex] = timestampMs;
-    unawaited(_unreadStore.saveChannelLastRead(
+    _unreadStore.saveChannelLastRead(
       Map<int, int>.from(_channelLastReadMs),
-    ));
+    );
     if (notify) {
       notifyListeners();
     }
@@ -2306,16 +2086,48 @@ class MeshCoreConnector extends ChangeNotifier {
   bool _addChannelMessage(int channelIndex, ChannelMessage message) {
     _channelMessages.putIfAbsent(channelIndex, () => []);
     final messages = _channelMessages[channelIndex]!;
-    final existingIndex = _findChannelRepeatIndex(messages, message);
+
+    // Parse reply info from message text
+    final replyInfo = ChannelMessage.parseReplyMention(message.text);
+    ChannelMessage processedMessage = message;
+
+    if (replyInfo != null) {
+      // Find original message by sender name (most recent match)
+      final originalMessage = _findMessageBySender(messages, replyInfo.mentionedNode);
+
+      if (originalMessage != null) {
+        // Create new message with reply metadata
+        processedMessage = ChannelMessage(
+          senderKey: message.senderKey,
+          senderName: message.senderName,
+          text: replyInfo.actualMessage,
+          timestamp: message.timestamp,
+          isOutgoing: message.isOutgoing,
+          status: message.status,
+          repeats: message.repeats,
+          repeatCount: message.repeatCount,
+          pathLength: message.pathLength,
+          pathBytes: message.pathBytes,
+          pathVariants: message.pathVariants,
+          channelIndex: message.channelIndex,
+          messageId: message.messageId,
+          replyToMessageId: originalMessage.messageId,
+          replyToSenderName: originalMessage.senderName,
+          replyToText: originalMessage.text,
+        );
+      }
+    }
+
+    final existingIndex = _findChannelRepeatIndex(messages, processedMessage);
     var isNew = true;
     if (existingIndex >= 0) {
       isNew = false;
       final existing = messages[existingIndex];
-      final mergedPathBytes = _selectPreferredPathBytes(existing.pathBytes, message.pathBytes);
-      final mergedPathVariants = _mergePathVariants(existing.pathVariants, message.pathVariants);
+      final mergedPathBytes = _selectPreferredPathBytes(existing.pathBytes, processedMessage.pathBytes);
+      final mergedPathVariants = _mergePathVariants(existing.pathVariants, processedMessage.pathVariants);
       final mergedPathLength = _mergePathLength(
         existing.pathLength,
-        message.pathLength,
+        processedMessage.pathLength,
         mergedPathBytes.length,
       );
       messages[existingIndex] = existing.copyWith(
@@ -2325,7 +2137,7 @@ class MeshCoreConnector extends ChangeNotifier {
         pathVariants: mergedPathVariants,
       );
     } else {
-      messages.add(message);
+      messages.add(processedMessage);
     }
 
     // Save to persistent storage
@@ -2336,6 +2148,16 @@ class MeshCoreConnector extends ChangeNotifier {
     return isNew;
   }
 
+  ChannelMessage? _findMessageBySender(List<ChannelMessage> messages, String mentionedNode) {
+    // Search backwards for most recent message from this sender
+    for (int i = messages.length - 1; i >= 0; i--) {
+      if (messages[i].senderName == mentionedNode && !messages[i].isOutgoing) {
+        return messages[i];
+      }
+    }
+    return null;
+  }
+
   int _findChannelRepeatIndex(List<ChannelMessage> messages, ChannelMessage incoming) {
     for (int i = messages.length - 1; i >= 0; i--) {
       final existing = messages[i];
@@ -2456,8 +2278,6 @@ class MeshCoreConnector extends ChangeNotifier {
     _maxChannels = _defaultMaxChannels;
     _isSyncingQueuedMessages = false;
     _queuedMessageSyncInFlight = false;
-    _voiceAssemblies.clear();
-    _voiceSendSession = null;
 
     _setState(MeshCoreConnectionState.disconnected);
     _scheduleReconnect();
@@ -2477,6 +2297,10 @@ class MeshCoreConnector extends ChangeNotifier {
     _notifySubscription?.cancel();
     _reconnectTimer?.cancel();
     _receivedFramesController.close();
+
+    // Flush pending unread writes before disposal
+    _unreadStore.flush();
+
     super.dispose();
   }
 }
@@ -2525,92 +2349,4 @@ class _ParsedText {
   });
 }
 
-class _VoiceAssembly {
-  _VoiceAssembly({
-    required this.senderKey,
-    required this.senderKeyHex,
-    required this.timestampSeconds,
-    required this.totalChunks,
-  });
 
-  final Uint8List senderKey;
-  final String senderKeyHex;
-  final int timestampSeconds;
-  final int totalChunks;
-  final DateTime startedAt = DateTime.now();
-  final Map<int, Uint8List> _chunks = {};
-
-  bool get isComplete => _chunks.length == totalChunks;
-
-  void addChunk(VoiceChunk chunk) {
-    _chunks.putIfAbsent(chunk.index, () => chunk.bytes);
-  }
-
-  Uint8List assemble() {
-    if (!isComplete) return Uint8List(0);
-    final builder = BytesBuilder(copy: false);
-    for (var i = 0; i < totalChunks; i++) {
-      final part = _chunks[i];
-      if (part == null) return Uint8List(0);
-      builder.add(part);
-    }
-    return builder.takeBytes();
-  }
-}
-
-class _VoiceSendSession {
-  _VoiceSendSession({
-    required this.contact,
-    required this.messageId,
-    required this.chunks,
-    required this.timestampSeconds,
-  });
-
-  final Contact contact;
-  final String messageId;
-  final List<String> chunks;
-  final int timestampSeconds;
-
-  int currentChunkIndex = -1;
-  Uint8List? expectedAckHash;
-  int? expectedTimeoutMs;
-  Completer<void>? sentCompleter;
-  Completer<void>? confirmCompleter;
-  bool _cancelled = false;
-
-  bool get isCancelled => _cancelled;
-
-  void beginChunk(int index) {
-    currentChunkIndex = index;
-    expectedAckHash = null;
-    expectedTimeoutMs = null;
-    sentCompleter = Completer<void>();
-    confirmCompleter = Completer<void>();
-  }
-
-  void handleSent(Uint8List ackHash, int timeoutMs) {
-    if (sentCompleter == null || sentCompleter!.isCompleted) return;
-    expectedAckHash = Uint8List.fromList(ackHash);
-    expectedTimeoutMs = timeoutMs > 0 ? timeoutMs : null;
-    sentCompleter!.complete();
-  }
-
-  void handleConfirmed(Uint8List ackHash) {
-    if (confirmCompleter == null || confirmCompleter!.isCompleted) return;
-    final expected = expectedAckHash;
-    if (expected == null) return;
-    if (!listEquals(expected, ackHash)) return;
-    confirmCompleter!.complete();
-  }
-
-  void cancel() {
-    if (_cancelled) return;
-    _cancelled = true;
-    if (sentCompleter != null && !sentCompleter!.isCompleted) {
-      sentCompleter!.completeError(StateError('cancelled'));
-    }
-    if (confirmCompleter != null && !confirmCompleter!.isCompleted) {
-      confirmCompleter!.completeError(StateError('cancelled'));
-    }
-  }
-}

lib/main.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
-import 'package:media_kit_fork/media_kit_fork.dart';
 
 import 'connector/meshcore_connector.dart';
 import 'screens/scanner_screen.dart';
@@ -12,10 +11,13 @@ import 'services/notification_service.dart';
 import 'services/ble_debug_log_service.dart';
 import 'services/background_service.dart';
 import 'services/map_tile_cache_service.dart';
+import 'storage/prefs_manager.dart';
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
-  MediaKit.ensureInitialized();
+
+  // Initialize SharedPreferences cache
+  await PrefsManager.initialize();
 
   // Initialize services
   final storage = StorageService();

lib/models/channel_message.dart

@@ -34,6 +34,10 @@ class ChannelMessage {
   final Uint8List pathBytes;
   final List<Uint8List> pathVariants;
   final int? channelIndex;
+  final String messageId;
+  final String? replyToMessageId;
+  final String? replyToSenderName;
+  final String? replyToText;
 
   ChannelMessage({
     this.senderKey,
@@ -48,7 +52,12 @@ class ChannelMessage {
     Uint8List? pathBytes,
     List<Uint8List>? pathVariants,
     this.channelIndex,
-  })  : pathBytes = pathBytes ?? Uint8List(0),
+    String? messageId,
+    this.replyToMessageId,
+    this.replyToSenderName,
+    this.replyToText,
+  })  : messageId = messageId ?? '${timestamp.millisecondsSinceEpoch}_${senderName.hashCode}_${text.hashCode}',
+        pathBytes = pathBytes ?? Uint8List(0),
         pathVariants = _mergePathVariants(
           pathBytes ?? Uint8List(0),
           pathVariants,
@@ -63,6 +72,9 @@ class ChannelMessage {
     int? pathLength,
     Uint8List? pathBytes,
     List<Uint8List>? pathVariants,
+    String? replyToMessageId,
+    String? replyToSenderName,
+    String? replyToText,
   }) {
     return ChannelMessage(
       senderKey: senderKey,
@@ -77,6 +89,10 @@ class ChannelMessage {
       pathBytes: pathBytes ?? this.pathBytes,
       pathVariants: pathVariants ?? this.pathVariants,
       channelIndex: channelIndex,
+      messageId: messageId,
+      replyToMessageId: replyToMessageId ?? this.replyToMessageId,
+      replyToSenderName: replyToSenderName ?? this.replyToSenderName,
+      replyToText: replyToText ?? this.replyToText,
     );
   }
 
@@ -207,4 +223,24 @@ class ChannelMessage {
     }
     return true;
   }
+
+  static ReplyInfo? parseReplyMention(String text) {
+    final regex = RegExp(r'^@\[([^\]]+)\]\s+(.+)$', dotAll: true);
+    final match = regex.firstMatch(text);
+    if (match == null) return null;
+    return ReplyInfo(
+      mentionedNode: match.group(1)!,
+      actualMessage: match.group(2)!,
+    );
+  }
+}
+
+class ReplyInfo {
+  final String mentionedNode;
+  final String actualMessage;
+
+  ReplyInfo({
+    required this.mentionedNode,
+    required this.actualMessage,
+  });
 }

lib/models/message.dart

@@ -10,10 +10,6 @@ class Message {
   final bool isOutgoing;
   final bool isCli;
   final MessageStatus status;
-  final bool isVoice;
-  final String? voicePath;
-  final int? voiceDurationMs;
-  final String? voiceCodec;
 
   // NEW: Retry logic fields
   final String? messageId;
@@ -34,10 +30,6 @@ class Message {
     required this.isOutgoing,
     this.isCli = false,
     this.status = MessageStatus.pending,
-    this.isVoice = false,
-    this.voicePath,
-    this.voiceDurationMs,
-    this.voiceCodec,
     this.messageId,
     this.retryCount = 0,
     this.estimatedTimeoutMs,
@@ -63,10 +55,6 @@ class Message {
     int? pathLength,
     Uint8List? pathBytes,
     bool? isCli,
-    bool? isVoice,
-    String? voicePath,
-    int? voiceDurationMs,
-    String? voiceCodec,
   }) {
     return Message(
       senderKey: senderKey,
@@ -75,10 +63,6 @@ class Message {
       isOutgoing: isOutgoing,
       isCli: isCli ?? this.isCli,
       status: status ?? this.status,
-      isVoice: isVoice ?? this.isVoice,
-      voicePath: voicePath ?? this.voicePath,
-      voiceDurationMs: voiceDurationMs ?? this.voiceDurationMs,
-      voiceCodec: voiceCodec ?? this.voiceCodec,
       messageId: messageId,
       retryCount: retryCount ?? this.retryCount,
       estimatedTimeoutMs: estimatedTimeoutMs ?? this.estimatedTimeoutMs,
@@ -117,7 +101,6 @@ class Message {
       isOutgoing: false,
       isCli: false,
       status: MessageStatus.delivered,
-      isVoice: false,
       pathBytes: Uint8List(0),
     );
   }
@@ -135,7 +118,6 @@ class Message {
       isOutgoing: true,
       isCli: false,
       status: MessageStatus.pending,
-      isVoice: false,
       pathLength: pathLength,
       pathBytes: pathBytes,
     );

lib/screens/channel_chat_screen.dart

@@ -32,6 +32,8 @@ class ChannelChatScreen extends StatefulWidget {
 class _ChannelChatScreenState extends State<ChannelChatScreen> {
   final TextEditingController _textController = TextEditingController();
   final ScrollController _scrollController = ScrollController();
+  ChannelMessage? _replyingToMessage;
+  final Map<String, GlobalKey> _messageKeys = {};
 
   @override
   void initState() {
@@ -60,6 +62,41 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
     }
   }
 
+  void _setReplyingTo(ChannelMessage message) {
+    setState(() {
+      _replyingToMessage = message;
+    });
+  }
+
+  void _cancelReply() {
+    setState(() {
+      _replyingToMessage = null;
+    });
+  }
+
+  Future<void> _scrollToMessage(String messageId) async {
+    final key = _messageKeys[messageId];
+    if (key == null) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(
+          content: Text('Original message not found'),
+          duration: Duration(seconds: 2),
+        ),
+      );
+      return;
+    }
+
+    final targetContext = key.currentContext;
+    if (targetContext == null) return;
+
+    await Scrollable.ensureVisible(
+      targetContext,
+      duration: const Duration(milliseconds: 300),
+      curve: Curves.easeInOut,
+      alignment: 0.3,
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -149,12 +186,16 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
                   return ListView.builder(
                     controller: _scrollController,
                     padding: const EdgeInsets.all(8),
-                    cacheExtent: 0,
-                    addAutomaticKeepAlives: false,
                     itemCount: messages.length,
                     itemBuilder: (context, index) {
                       final message = messages[index];
-                      return _buildMessageBubble(message);
+                      if (!_messageKeys.containsKey(message.messageId)) {
+                        _messageKeys[message.messageId] = GlobalKey();
+                      }
+                      return Container(
+                        key: _messageKeys[message.messageId]!,
+                        child: _buildMessageBubble(message),
+                      );
                     },
                   );
                 },
@@ -214,6 +255,10 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
                       ),
                       const SizedBox(height: 4),
                     ],
+                    if (message.replyToMessageId != null) ...[
+                      _buildReplyPreview(message),
+                      const SizedBox(height: 8),
+                    ],
                     if (poi != null)
                       _buildPoiMessage(context, poi, isOutgoing)
                     else if (gifId != null)
@@ -282,6 +327,79 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
     );
   }
 
+  Widget _buildReplyPreview(ChannelMessage message) {
+    final connector = context.read<MeshCoreConnector>();
+    final isOwnNode = message.replyToSenderName == connector.selfName;
+    final replyText = message.replyToText ?? '';
+
+    final gifId = _parseGifId(replyText);
+    final poi = _parsePoiMessage(replyText);
+
+    Widget contentPreview;
+    if (gifId != null) {
+      contentPreview = Row(
+        children: [
+          Icon(Icons.gif_box, size: 14, color: Colors.grey[600]),
+          const SizedBox(width: 4),
+          Text('GIF', style: TextStyle(fontSize: 12, color: Colors.grey[700])),
+        ],
+      );
+    } else if (poi != null) {
+      contentPreview = Row(
+        children: [
+          Icon(Icons.location_on_outlined, size: 14, color: Colors.grey[600]),
+          const SizedBox(width: 4),
+          Text('Location', style: TextStyle(fontSize: 12, color: Colors.grey[700])),
+        ],
+      );
+    } else {
+      contentPreview = Text(
+        replyText,
+        maxLines: 2,
+        overflow: TextOverflow.ellipsis,
+        style: TextStyle(
+          fontSize: 12,
+          color: Colors.grey[700],
+          fontStyle: FontStyle.italic,
+        ),
+      );
+    }
+
+    return GestureDetector(
+      onTap: () => _scrollToMessage(message.replyToMessageId!),
+      child: Container(
+        padding: const EdgeInsets.all(8),
+        decoration: BoxDecoration(
+          color: Colors.black.withValues(alpha: 0.05),
+          borderRadius: BorderRadius.circular(8),
+          border: Border(
+            left: BorderSide(
+              color: Theme.of(context).colorScheme.primary,
+              width: 3,
+            ),
+          ),
+        ),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              'Reply to ${message.replyToSenderName}',
+              style: TextStyle(
+                fontSize: 11,
+                fontWeight: FontWeight.bold,
+                color: isOwnNode
+                    ? Theme.of(context).colorScheme.primary
+                    : Theme.of(context).colorScheme.onSurface,
+              ),
+            ),
+            const SizedBox(height: 2),
+            contentPreview,
+          ],
+        ),
+      ),
+    );
+  }
+
   String? _parseGifId(String text) {
     final trimmed = text.trim();
     final match = RegExp(r'^g:([A-Za-z0-9_-]+)$').firstMatch(trimmed);
@@ -412,22 +530,84 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
     return colors[hash.abs() % colors.length];
   }
 
-  Widget _buildMessageComposer() {
-    final connector = context.watch<MeshCoreConnector>();
-    final maxBytes = maxChannelMessageBytes(connector.selfName);
+  Widget _buildReplyBanner() {
+    final message = _replyingToMessage!;
     return Container(
-      padding: const EdgeInsets.all(8),
+      width: double.infinity,
+      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
       decoration: BoxDecoration(
-        color: Theme.of(context).colorScheme.surface,
-        boxShadow: [
-          BoxShadow(
-            color: Colors.black.withValues(alpha: 0.1),
-            blurRadius: 4,
-            offset: const Offset(0, -2),
+        color: Theme.of(context).colorScheme.secondaryContainer,
+        border: Border(
+          bottom: BorderSide(
+            color: Theme.of(context).dividerColor,
+            width: 1,
+          ),
+        ),
+      ),
+      child: Row(
+        children: [
+          Icon(
+            Icons.reply,
+            size: 18,
+            color: Theme.of(context).colorScheme.onSecondaryContainer,
+          ),
+          const SizedBox(width: 8),
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  'Replying to ${message.senderName}',
+                  style: TextStyle(
+                    fontSize: 12,
+                    fontWeight: FontWeight.bold,
+                    color: Theme.of(context).colorScheme.onSecondaryContainer,
+                  ),
+                ),
+                Text(
+                  message.text,
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                  style: TextStyle(
+                    fontSize: 11,
+                    color: Theme.of(context).colorScheme.onSecondaryContainer.withValues(alpha: 0.7),
+                  ),
+                ),
+              ],
+            ),
+          ),
+          IconButton(
+            icon: const Icon(Icons.close, size: 18),
+            onPressed: _cancelReply,
+            color: Theme.of(context).colorScheme.onSecondaryContainer,
+            padding: EdgeInsets.zero,
+            constraints: const BoxConstraints(),
           ),
         ],
       ),
-      child: Row(
+    );
+  }
+
+  Widget _buildMessageComposer() {
+    final connector = context.watch<MeshCoreConnector>();
+    final maxBytes = maxChannelMessageBytes(connector.selfName);
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        if (_replyingToMessage != null) _buildReplyBanner(),
+        Container(
+          padding: const EdgeInsets.all(8),
+          decoration: BoxDecoration(
+            color: Theme.of(context).colorScheme.surface,
+            boxShadow: [
+              BoxShadow(
+                color: Colors.black.withValues(alpha: 0.1),
+                blurRadius: 4,
+                offset: const Offset(0, -2),
+              ),
+            ],
+          ),
+          child: Row(
         children: [
           IconButton(
             icon: const Icon(Icons.gif_box),
@@ -491,7 +671,9 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
             color: Theme.of(context).colorScheme.primary,
           ),
         ],
-      ),
+          ),
+        ),
+      ],
     );
   }
 
@@ -500,16 +682,23 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
     if (text.isEmpty) return;
 
     final connector = context.read<MeshCoreConnector>();
+
+    String messageText = text;
+    if (_replyingToMessage != null) {
+      messageText = '@[${_replyingToMessage!.senderName}] $text';
+    }
+
     final maxBytes = maxChannelMessageBytes(connector.selfName);
-    if (utf8.encode(text).length > maxBytes) {
+    if (utf8.encode(messageText).length > maxBytes) {
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(content: Text('Message too long (max $maxBytes bytes).')),
       );
       return;
     }
 
-    connector.sendChannelMessage(widget.channel, text);
+    connector.sendChannelMessage(widget.channel, messageText);
     _textController.clear();
+    _cancelReply();
   }
 
   String _formatTime(DateTime time) {
@@ -539,6 +728,14 @@ class _ChannelChatScreenState extends State<ChannelChatScreen> {
         child: Column(
           mainAxisSize: MainAxisSize.min,
           children: [
+            ListTile(
+              leading: const Icon(Icons.reply),
+              title: const Text('Reply'),
+              onTap: () {
+                Navigator.pop(sheetContext);
+                _setReplyingTo(message);
+              },
+            ),
             ListTile(
               leading: const Icon(Icons.copy),
               title: const Text('Copy'),

lib/screens/channels_screen.dart

@@ -7,7 +7,10 @@ import 'package:provider/provider.dart';
 
 import '../connector/meshcore_connector.dart';
 import '../models/channel.dart';
+import '../utils/dialog_utils.dart';
+import '../utils/disconnect_navigation_mixin.dart';
 import '../utils/route_transitions.dart';
+import '../widgets/empty_state.dart';
 import '../widgets/quick_switch_bar.dart';
 import '../widgets/unread_badge.dart';
 import 'channel_chat_screen.dart';
@@ -27,7 +30,8 @@ class ChannelsScreen extends StatefulWidget {
   State<ChannelsScreen> createState() => _ChannelsScreenState();
 }
 
-class _ChannelsScreenState extends State<ChannelsScreen> {
+class _ChannelsScreenState extends State<ChannelsScreen>
+    with DisconnectNavigationMixin {
   @override
   void initState() {
     super.initState();
@@ -39,6 +43,12 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
   @override
   Widget build(BuildContext context) {
     final connector = context.watch<MeshCoreConnector>();
+
+    // Auto-navigate back to scanner if disconnected
+    if (!checkConnectionAndNavigate(connector)) {
+      return const SizedBox.shrink();
+    }
+
     final allowBack = !connector.isConnected;
 
     return PopScope(
@@ -77,23 +87,13 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
             final channels = connector.channels;
 
             if (channels.isEmpty) {
-              return Center(
-                child: Column(
-                  mainAxisAlignment: MainAxisAlignment.center,
-                  children: [
-                    Icon(Icons.tag, size: 64, color: Colors.grey[400]),
-                    const SizedBox(height: 16),
-                    Text(
-                      'No channels configured',
-                      style: TextStyle(fontSize: 16, color: Colors.grey[600]),
-                    ),
-                    const SizedBox(height: 24),
-                    FilledButton.icon(
-                      onPressed: () => _addPublicChannel(context, connector),
-                      icon: const Icon(Icons.public),
-                      label: const Text('Add Public Channel'),
-                    ),
-                  ],
+              return EmptyState(
+                icon: Icons.tag,
+                title: 'No channels configured',
+                action: FilledButton.icon(
+                  onPressed: () => _addPublicChannel(context, connector),
+                  icon: const Icon(Icons.public),
+                  label: const Text('Add Public Channel'),
                 ),
               );
             }
@@ -190,14 +190,17 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
             ),
           ],
         ),
-        onTap: () {
+        onTap: () async {
           connector.markChannelRead(channel.index);
-          Navigator.push(
-            context,
-            MaterialPageRoute(
-              builder: (context) => ChannelChatScreen(channel: channel),
-            ),
-          );
+          await Future.delayed(const Duration(milliseconds: 50));
+          if (context.mounted) {
+            Navigator.push(
+              context,
+              MaterialPageRoute(
+                builder: (context) => ChannelChatScreen(channel: channel),
+              ),
+            );
+          }
         },
         onLongPress: () => _showChannelActions(context, connector, channel),
       ),
@@ -218,17 +221,23 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
             ListTile(
               leading: const Icon(Icons.edit_outlined),
               title: const Text('Edit channel'),
-              onTap: () {
+              onTap: () async {
                 Navigator.pop(context);
-                _showEditChannelDialog(context, connector, channel);
+                await Future.delayed(const Duration(milliseconds: 100));
+                if (context.mounted) {
+                  _showEditChannelDialog(context, connector, channel);
+                }
               },
             ),
             ListTile(
               leading: const Icon(Icons.delete_outline, color: Colors.red),
               title: const Text('Delete channel', style: TextStyle(color: Colors.red)),
-              onTap: () {
+              onTap: () async {
                 Navigator.pop(context);
-                _confirmDeleteChannel(context, connector, channel);
+                await Future.delayed(const Duration(milliseconds: 100));
+                if (context.mounted) {
+                  _confirmDeleteChannel(context, connector, channel);
+                }
               },
             ),
           ],
@@ -261,27 +270,7 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
 
   Future<void> _disconnect(BuildContext context) async {
     final connector = context.read<MeshCoreConnector>();
-    final confirmed = await showDialog<bool>(
-      context: context,
-      builder: (context) => AlertDialog(
-        title: const Text('Disconnect'),
-        content: const Text('Are you sure you want to disconnect from this device?'),
-        actions: [
-          TextButton(
-            onPressed: () => Navigator.pop(context, false),
-            child: const Text('Cancel'),
-          ),
-          TextButton(
-            onPressed: () => Navigator.pop(context, true),
-            child: const Text('Disconnect'),
-          ),
-        ],
-      ),
-    );
-
-    if (confirmed == true) {
-      await connector.disconnect();
-    }
+    await showDisconnectDialog(context, connector);
   }
 
   void _showAddChannelDialog(BuildContext context) {
@@ -402,9 +391,11 @@ class _ChannelsScreenState extends State<ChannelsScreen> {
 
                 Navigator.pop(context);
                 connector.setChannel(selectedIndex, name, psk);
-                ScaffoldMessenger.of(context).showSnackBar(
-                  SnackBar(content: Text('Channel "$name" added')),
-                );
+                if (context.mounted) {
+                  ScaffoldMessenger.of(context).showSnackBar(
+                    SnackBar(content: Text('Channel "$name" added')),
+                  );
+                }
               },
               child: const Text('Add'),
             ),

lib/screens/chat_screen.dart

@@ -1,13 +1,10 @@
 import 'dart:async';
 import 'dart:convert';
-import 'dart:io';
-import 'dart:typed_data';
 
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
 import 'package:latlong2/latlong.dart';
-import 'package:record/record.dart';
 
 import '../connector/meshcore_connector.dart';
 import '../connector/meshcore_protocol.dart';
@@ -15,14 +12,12 @@ import '../helpers/utf8_length_limiter.dart';
 import '../models/channel_message.dart';
 import '../models/contact.dart';
 import '../models/message.dart';
-import '../services/voice_message_service.dart';
 import '../services/path_history_service.dart';
 import 'channel_message_path_screen.dart';
 import 'map_screen.dart';
 import '../utils/emoji_utils.dart';
 import '../widgets/gif_message.dart';
 import '../widgets/gif_picker.dart';
-import '../widgets/voice_message.dart';
 
 class ChatScreen extends StatefulWidget {
   final Contact contact;
@@ -37,16 +32,6 @@ class _ChatScreenState extends State<ChatScreen> {
   final _textController = TextEditingController();
   final _scrollController = ScrollController();
   bool _forceFlood = false;
-  final AudioRecorder _voiceRecorder = AudioRecorder();
-  StreamSubscription<Uint8List>? _voiceStreamSubscription;
-  BytesBuilder _voiceBuffer = BytesBuilder(copy: false);
-  Timer? _voiceRecordTimer;
-  bool _isRecordingVoice = false;
-  Message? _pendingVoiceMessage;
-  Uint8List? _pendingVoiceCodec2Bytes;
-  int? _pendingVoiceTimestampSeconds;
-  int? _pendingVoiceDurationMs;
-  String? _pendingVoicePath;
 
   @override
   void initState() {
@@ -62,11 +47,6 @@ class _ChatScreenState extends State<ChatScreen> {
     context.read<MeshCoreConnector>().setActiveContact(null);
     _textController.dispose();
     _scrollController.dispose();
-    _voiceRecordTimer?.cancel();
-    _voiceStreamSubscription?.cancel();
-    unawaited(_voiceRecorder.stop());
-    _voiceRecorder.dispose();
-    unawaited(_clearPendingVoicePreview(deleteFile: true, notify: false));
     super.dispose();
   }
 
@@ -204,8 +184,6 @@ class _ChatScreenState extends State<ChatScreen> {
     return ListView.builder(
       controller: _scrollController,
       padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 16),
-      cacheExtent: 0,
-      addAutomaticKeepAlives: false,
       itemCount: messages.length,
       itemBuilder: (context, index) {
         final message = messages[index];
@@ -221,9 +199,6 @@ class _ChatScreenState extends State<ChatScreen> {
 
   Widget _buildInputBar(MeshCoreConnector connector) {
     final maxBytes = maxContactMessageBytes();
-    final isVoiceBusy = connector.isVoiceSending;
-    final voiceSupported = Platform.isAndroid || Platform.isIOS;
-    final hasPendingVoice = _pendingVoiceMessage != null;
     final colorScheme = Theme.of(context).colorScheme;
     return Container(
       padding: const EdgeInsets.all(8),
@@ -236,93 +211,59 @@ class _ChatScreenState extends State<ChatScreen> {
       child: SafeArea(
         child: Row(
           children: [
-            if (voiceSupported)
-              IconButton(
-                icon: Icon(_isRecordingVoice ? Icons.stop_circle : Icons.mic),
-                onPressed: (isVoiceBusy || hasPendingVoice) ? null : () => _toggleVoiceRecording(connector),
-                tooltip: _isRecordingVoice ? 'Stop recording' : 'Record voice',
-              ),
             IconButton(
               icon: const Icon(Icons.gif_box),
-              onPressed: (_isRecordingVoice || isVoiceBusy || hasPendingVoice)
-                  ? null
-                  : () => _showGifPicker(context),
+              onPressed: () => _showGifPicker(context),
               tooltip: 'Send GIF',
             ),
             Expanded(
-              child: hasPendingVoice
-                  ? _buildVoicePreview(colorScheme)
-                  : ValueListenableBuilder<TextEditingValue>(
-                      valueListenable: _textController,
-                      builder: (context, value, child) {
-                        final gifId = _parseGifId(value.text);
-                        if (gifId != null) {
-                          return Row(
-                            children: [
-                              Expanded(
-                                child: GifMessage(
-                                  url: 'https://media.giphy.com/media/$gifId/giphy.gif',
-                                  backgroundColor: colorScheme.surfaceContainerHighest,
-                                  fallbackTextColor:
-                                      colorScheme.onSurface.withValues(alpha: 0.6),
-                                  width: 160,
-                                  height: 110,
-                                ),
-                              ),
-                              const SizedBox(width: 8),
-                              IconButton(
-                                icon: const Icon(Icons.close),
-                                onPressed: () => _textController.clear(),
-                              ),
-                            ],
-                          );
-                        }
-
-                        return TextField(
-                          controller: _textController,
-                          enabled: !_isRecordingVoice && !isVoiceBusy,
-                          inputFormatters: [
-                            Utf8LengthLimitingTextInputFormatter(maxBytes),
-                          ],
-                          decoration: const InputDecoration(
-                            hintText: 'Type a message...',
-                            border: OutlineInputBorder(),
-                            contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+              child: ValueListenableBuilder<TextEditingValue>(
+                valueListenable: _textController,
+                builder: (context, value, child) {
+                  final gifId = _parseGifId(value.text);
+                  if (gifId != null) {
+                    return Row(
+                      children: [
+                        Expanded(
+                          child: GifMessage(
+                            url: 'https://media.giphy.com/media/$gifId/giphy.gif',
+                            backgroundColor: colorScheme.surfaceContainerHighest,
+                            fallbackTextColor:
+                                colorScheme.onSurface.withValues(alpha: 0.6),
+                            width: 160,
+                            height: 110,
                           ),
-                          textInputAction: TextInputAction.send,
-                          onSubmitted: (_isRecordingVoice || isVoiceBusy)
-                              ? null
-                              : (_) => _sendMessage(connector),
-                        );
-                      },
+                        ),
+                        const SizedBox(width: 8),
+                        IconButton(
+                          icon: const Icon(Icons.close),
+                          onPressed: () => _textController.clear(),
+                        ),
+                      ],
+                    );
+                  }
+
+                  return TextField(
+                    controller: _textController,
+                    inputFormatters: [
+                      Utf8LengthLimitingTextInputFormatter(maxBytes),
+                    ],
+                    decoration: const InputDecoration(
+                      hintText: 'Type a message...',
+                      border: OutlineInputBorder(),
+                      contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
                     ),
+                    textInputAction: TextInputAction.send,
+                    onSubmitted: (_) => _sendMessage(connector),
+                  );
+                },
+              ),
             ),
             const SizedBox(width: 8),
-            if (isVoiceBusy)
-              IconButton.filled(
-                icon: const Icon(Icons.stop_circle),
-                onPressed: () => _cancelVoiceSend(connector),
-                tooltip: 'Cancel voice send',
-              )
-            else if (hasPendingVoice) ...[
-              IconButton(
-                icon: const Icon(Icons.close),
-                onPressed: () => _clearPendingVoicePreview(deleteFile: true),
-                tooltip: 'Discard voice message',
-              ),
-              IconButton.filled(
-                icon: const Icon(Icons.send),
-                onPressed: () => _sendPendingVoice(connector),
-                tooltip: 'Send voice message',
-              ),
-            ]
-            else
-              IconButton.filled(
-                icon: const Icon(Icons.send),
-                onPressed: (_isRecordingVoice || isVoiceBusy)
-                    ? null
-                    : () => _sendMessage(connector),
-              ),
+            IconButton.filled(
+              icon: const Icon(Icons.send),
+              onPressed: () => _sendMessage(connector),
+            ),
           ],
         ),
       ),
@@ -377,208 +318,6 @@ class _ChatScreenState extends State<ChatScreen> {
     });
   }
 
-  void _cancelVoiceSend(MeshCoreConnector connector) {
-    connector.cancelVoiceSend();
-    if (!mounted) return;
-    ScaffoldMessenger.of(context).showSnackBar(
-      const SnackBar(content: Text('Voice send canceled')),
-    );
-  }
-
-  Future<void> _toggleVoiceRecording(MeshCoreConnector connector) async {
-    if (_isRecordingVoice) {
-      await _stopVoiceRecording(connector);
-    } else {
-      await _startVoiceRecording();
-    }
-  }
-
-  Future<void> _startVoiceRecording() async {
-    if (_isRecordingVoice) return;
-    final hasPermission = await _voiceRecorder.hasPermission();
-    if (!hasPermission) {
-      if (!mounted) return;
-      ScaffoldMessenger.of(context).showSnackBar(
-        const SnackBar(content: Text('Microphone permission denied')),
-      );
-      return;
-    }
-
-    _voiceBuffer = BytesBuilder(copy: false);
-    try {
-      final stream = await _voiceRecorder.startStream(
-        const RecordConfig(
-          encoder: AudioEncoder.pcm16bits,
-          sampleRate: VoiceMessageService.sampleRate,
-          numChannels: VoiceMessageService.channels,
-        ),
-      );
-      _voiceStreamSubscription = stream.listen((data) {
-        _voiceBuffer.add(data);
-      });
-    } catch (e) {
-      if (!mounted) return;
-      ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(content: Text('Failed to start recording: $e')),
-      );
-      return;
-    }
-    _voiceRecordTimer?.cancel();
-    _voiceRecordTimer = Timer(
-      const Duration(seconds: VoiceMessageService.maxRecordSeconds),
-      () => _stopVoiceRecording(context.read<MeshCoreConnector>()),
-    );
-    setState(() {
-      _isRecordingVoice = true;
-    });
-  }
-
-  Future<void> _stopVoiceRecording(MeshCoreConnector connector) async {
-    if (!_isRecordingVoice) return;
-    _voiceRecordTimer?.cancel();
-    await _voiceRecorder.stop();
-    await _voiceStreamSubscription?.cancel();
-    _voiceStreamSubscription = null;
-    final pcmBytes = _voiceBuffer.takeBytes();
-    setState(() {
-      _isRecordingVoice = false;
-    });
-    if (pcmBytes.isEmpty) return;
-    await _prepareVoicePreview(connector, pcmBytes);
-  }
-
-  Future<void> _prepareVoicePreview(MeshCoreConnector connector, Uint8List pcmBytes) async {
-    final voiceService = VoiceMessageService.instance;
-    try {
-      final codec2Bytes = voiceService.encodePcmToCodec2(pcmBytes);
-      if (codec2Bytes.isEmpty) return;
-      final timestampSeconds = connector.reserveVoiceTimestampSeconds();
-      final durationMs = voiceService.durationMsForCodec2Bytes(codec2Bytes);
-      final decodedPcm = voiceService.decodeCodec2ToPcm(codec2Bytes);
-      final fileName = voiceService.buildVoiceFileName(
-        senderKeyHex: widget.contact.publicKeyHex,
-        timestampSeconds: timestampSeconds,
-        outgoing: true,
-      );
-      final voicePath = await voiceService.writeWavFile(
-        pcmBytes: decodedPcm,
-        fileName: fileName,
-      );
-
-      final previewMessage = Message(
-        senderKey: widget.contact.publicKey,
-        text: 'Voice message',
-        timestamp: DateTime.fromMillisecondsSinceEpoch(timestampSeconds * 1000),
-        isOutgoing: true,
-        isCli: false,
-        status: MessageStatus.pending,
-        isVoice: true,
-        voicePath: voicePath,
-        voiceDurationMs: durationMs,
-        voiceCodec: VoiceMessageService.codecName,
-      );
-
-      if (!mounted) return;
-      setState(() {
-        _pendingVoiceMessage = previewMessage;
-        _pendingVoiceCodec2Bytes = codec2Bytes;
-        _pendingVoiceTimestampSeconds = timestampSeconds;
-        _pendingVoiceDurationMs = durationMs;
-        _pendingVoicePath = voicePath;
-      });
-    } catch (e) {
-      if (!mounted) return;
-      ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(content: Text('Voice message failed: $e')),
-      );
-    }
-  }
-
-  Widget _buildVoicePreview(ColorScheme colorScheme) {
-    final message = _pendingVoiceMessage;
-    if (message == null) {
-      return const SizedBox.shrink();
-    }
-
-    return Container(
-      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
-      decoration: BoxDecoration(
-        color: colorScheme.surfaceContainerHighest,
-        borderRadius: BorderRadius.circular(12),
-      ),
-      child: VoiceMessageBubble(
-        message: message,
-        backgroundColor: colorScheme.surfaceContainerHighest,
-        textColor: colorScheme.onSurface,
-        metaColor: colorScheme.onSurface.withValues(alpha: 0.7),
-        isOutgoing: true,
-      ),
-    );
-  }
-
-  Future<void> _sendPendingVoice(MeshCoreConnector connector) async {
-    final codec2Bytes = _pendingVoiceCodec2Bytes;
-    final voicePath = _pendingVoicePath;
-    final durationMs = _pendingVoiceDurationMs;
-    final timestampSeconds = _pendingVoiceTimestampSeconds;
-
-    if (codec2Bytes == null ||
-        codec2Bytes.isEmpty ||
-        voicePath == null ||
-        voicePath.isEmpty ||
-        durationMs == null ||
-        timestampSeconds == null) {
-      return;
-    }
-    if (!connector.isConnected) {
-      if (!mounted) return;
-      ScaffoldMessenger.of(context).showSnackBar(
-        const SnackBar(content: Text('Not connected to a MeshCore device')),
-      );
-      return;
-    }
-    if (connector.isVoiceSending) {
-      return;
-    }
-
-    await connector.sendVoiceMessage(
-      contact: widget.contact,
-      codec2Bytes: codec2Bytes,
-      voicePath: voicePath,
-      durationMs: durationMs,
-      timestampSeconds: timestampSeconds,
-    );
-    unawaited(_clearPendingVoicePreview(deleteFile: false));
-  }
-
-  Future<void> _clearPendingVoicePreview({required bool deleteFile, bool notify = true}) async {
-    final path = _pendingVoicePath;
-    if (notify && mounted) {
-      setState(() {
-        _pendingVoiceMessage = null;
-        _pendingVoiceCodec2Bytes = null;
-        _pendingVoiceTimestampSeconds = null;
-        _pendingVoiceDurationMs = null;
-        _pendingVoicePath = null;
-      });
-    } else {
-      _pendingVoiceMessage = null;
-      _pendingVoiceCodec2Bytes = null;
-      _pendingVoiceTimestampSeconds = null;
-      _pendingVoiceDurationMs = null;
-      _pendingVoicePath = null;
-    }
-    if (deleteFile && path != null && path.isNotEmpty) {
-      try {
-        final file = File(path);
-        if (await file.exists()) {
-          await file.delete();
-        }
-      } catch (_) {
-        return;
-      }
-    }
-  }
 
   void _showPathHistory(BuildContext context) {
     final connector = Provider.of<MeshCoreConnector>(context, listen: false);
@@ -1279,15 +1018,14 @@ class _ChatScreenState extends State<ChatScreen> {
         child: Column(
           mainAxisSize: MainAxisSize.min,
           children: [
-            if (!message.isVoice)
-              ListTile(
-                leading: const Icon(Icons.copy),
-                title: const Text('Copy'),
-                onTap: () {
-                  Navigator.pop(sheetContext);
-                  _copyMessageText(message.text);
-                },
-              ),
+            ListTile(
+              leading: const Icon(Icons.copy),
+              title: const Text('Copy'),
+              onTap: () {
+                Navigator.pop(sheetContext);
+                _copyMessageText(message.text);
+              },
+            ),
             ListTile(
               leading: const Icon(Icons.delete_outline),
               title: const Text('Delete'),
@@ -1297,8 +1035,7 @@ class _ChatScreenState extends State<ChatScreen> {
               },
             ),
             if (message.isOutgoing &&
-                message.status == MessageStatus.failed &&
-                !message.isVoice)
+                message.status == MessageStatus.failed)
               ListTile(
                 leading: const Icon(Icons.refresh),
                 title: const Text('Retry'),
@@ -1412,15 +1149,7 @@ class _MessageBubble extends StatelessWidget {
                       ),
                       const SizedBox(height: 4),
                     ],
-                    if (message.isVoice)
-                      VoiceMessageBubble(
-                        message: message,
-                        backgroundColor: bubbleColor,
-                        textColor: textColor,
-                        metaColor: metaColor,
-                        isOutgoing: isOutgoing,
-                      )
-                    else if (poi != null)
+                    if (poi != null)
                       _buildPoiMessage(context, poi, textColor, metaColor)
                     else if (gifId != null)
                       GifMessage(

lib/screens/contacts_screen.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
@@ -7,8 +9,11 @@ import '../models/contact.dart';
 import '../models/contact_group.dart';
 import '../storage/contact_group_store.dart';
 import '../utils/contact_search.dart';
+import '../utils/dialog_utils.dart';
+import '../utils/disconnect_navigation_mixin.dart';
 import '../utils/emoji_utils.dart';
 import '../utils/route_transitions.dart';
+import '../widgets/empty_state.dart';
 import '../widgets/quick_switch_bar.dart';
 import '../widgets/repeater_login_dialog.dart';
 import '../widgets/unread_badge.dart';
@@ -46,7 +51,8 @@ class ContactsScreen extends StatefulWidget {
   State<ContactsScreen> createState() => _ContactsScreenState();
 }
 
-class _ContactsScreenState extends State<ContactsScreen> {
+class _ContactsScreenState extends State<ContactsScreen>
+    with DisconnectNavigationMixin {
   final TextEditingController _searchController = TextEditingController();
   String _searchQuery = '';
   ContactSortOption _sortOption = ContactSortOption.lastSeen;
@@ -54,6 +60,7 @@ class _ContactsScreenState extends State<ContactsScreen> {
   bool _showUnreadOnly = false;
   final ContactGroupStore _groupStore = ContactGroupStore();
   List<ContactGroup> _groups = [];
+  Timer? _searchDebounce;
 
   @override
   void initState() {
@@ -63,6 +70,7 @@ class _ContactsScreenState extends State<ContactsScreen> {
 
   @override
   void dispose() {
+    _searchDebounce?.cancel();
     _searchController.dispose();
     super.dispose();
   }
@@ -82,16 +90,13 @@ class _ContactsScreenState extends State<ContactsScreen> {
   @override
   Widget build(BuildContext context) {
     final connector = context.watch<MeshCoreConnector>();
-    final allowBack = !connector.isConnected;
 
-    if (!connector.isConnected) {
-      WidgetsBinding.instance.addPostFrameCallback((_) {
-        if (context.mounted) {
-          Navigator.popUntil(context, (route) => route.isFirst);
-        }
-      });
+    // Auto-navigate back to scanner if disconnected
+    if (!checkConnectionAndNavigate(connector)) {
+      return const SizedBox.shrink();
     }
 
+    final allowBack = !connector.isConnected;
     final theme = Theme.of(context);
 
     return PopScope(
@@ -245,27 +250,7 @@ class _ContactsScreenState extends State<ContactsScreen> {
     BuildContext context,
     MeshCoreConnector connector,
   ) async {
-    final confirmed = await showDialog<bool>(
-      context: context,
-      builder: (context) => AlertDialog(
-        title: const Text('Disconnect'),
-        content: const Text('Are you sure you want to disconnect from this device?'),
-        actions: [
-          TextButton(
-            onPressed: () => Navigator.pop(context, false),
-            child: const Text('Cancel'),
-          ),
-          TextButton(
-            onPressed: () => Navigator.pop(context, true),
-            child: const Text('Disconnect'),
-          ),
-        ],
-      ),
-    );
-
-    if (confirmed == true) {
-      await connector.disconnect();
-    }
+    await showDisconnectDialog(context, connector);
   }
 
   Widget _buildContactsBody(BuildContext context, MeshCoreConnector connector) {
@@ -276,23 +261,10 @@ class _ContactsScreenState extends State<ContactsScreen> {
     }
 
     if (contacts.isEmpty && _groups.isEmpty) {
-      return Center(
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: [
-            Icon(Icons.people_outline, size: 64, color: Colors.grey[400]),
-            const SizedBox(height: 16),
-            Text(
-              'No contacts yet',
-              style: TextStyle(fontSize: 16, color: Colors.grey[600]),
-            ),
-            const SizedBox(height: 8),
-            Text(
-              'Contacts will appear when devices advertise',
-              style: TextStyle(fontSize: 14, color: Colors.grey[500]),
-            ),
-          ],
-        ),
+      return const EmptyState(
+        icon: Icons.people_outline,
+        title: 'No contacts yet',
+        subtitle: 'Contacts will appear when devices advertise',
       );
     }
 
@@ -326,8 +298,12 @@ class _ContactsScreenState extends State<ContactsScreen> {
               contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
             ),
             onChanged: (value) {
-              setState(() {
-                _searchQuery = value.toLowerCase();
+              _searchDebounce?.cancel();
+              _searchDebounce = Timer(const Duration(milliseconds: 300), () {
+                if (!mounted) return;
+                setState(() {
+                  _searchQuery = value.toLowerCase();
+                });
               });
             },
           ),

lib/screens/device_screen.dart

@@ -2,6 +2,8 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
 import '../connector/meshcore_connector.dart';
+import '../utils/dialog_utils.dart';
+import '../utils/disconnect_navigation_mixin.dart';
 import '../utils/route_transitions.dart';
 import '../widgets/quick_switch_bar.dart';
 import 'channels_screen.dart';
@@ -17,7 +19,8 @@ class DeviceScreen extends StatefulWidget {
   State<DeviceScreen> createState() => _DeviceScreenState();
 }
 
-class _DeviceScreenState extends State<DeviceScreen> {
+class _DeviceScreenState extends State<DeviceScreen>
+    with DisconnectNavigationMixin {
   bool _showBatteryVoltage = false;
   int _quickIndex = 0;
 
@@ -25,13 +28,9 @@ class _DeviceScreenState extends State<DeviceScreen> {
   Widget build(BuildContext context) {
     return Consumer<MeshCoreConnector>(
       builder: (context, connector, child) {
-        // If disconnected, pop back to scanner
-        if (!connector.isConnected) {
-          WidgetsBinding.instance.addPostFrameCallback((_) {
-            if (context.mounted) {
-              Navigator.popUntil(context, (route) => route.isFirst);
-            }
-          });
+        // Auto-navigate back to scanner if disconnected
+        if (!checkConnectionAndNavigate(connector)) {
+          return const SizedBox.shrink();
         }
 
         final theme = Theme.of(context);
@@ -286,26 +285,6 @@ class _DeviceScreenState extends State<DeviceScreen> {
     BuildContext context,
     MeshCoreConnector connector,
   ) async {
-    final confirmed = await showDialog<bool>(
-      context: context,
-      builder: (context) => AlertDialog(
-        title: const Text('Disconnect'),
-        content: const Text('Are you sure you want to disconnect from this device?'),
-        actions: [
-          TextButton(
-            onPressed: () => Navigator.pop(context, false),
-            child: const Text('Cancel'),
-          ),
-          TextButton(
-            onPressed: () => Navigator.pop(context, true),
-            child: const Text('Disconnect'),
-          ),
-        ],
-      ),
-    );
-
-    if (confirmed == true) {
-      await connector.disconnect();
-    }
+    await showDisconnectDialog(context, connector);
   }
 }

lib/services/app_settings_service.dart

@@ -1,7 +1,7 @@
 import 'dart:convert';
 import 'package:flutter/foundation.dart';
-import 'package:shared_preferences/shared_preferences.dart';
 import '../models/app_settings.dart';
+import '../storage/prefs_manager.dart';
 
 class AppSettingsService extends ChangeNotifier {
   static const String _settingsKey = 'app_settings';
@@ -17,7 +17,7 @@ class AppSettingsService extends ChangeNotifier {
   }
 
   Future<void> loadSettings() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_settingsKey);
 
     if (jsonStr != null) {
@@ -36,7 +36,7 @@ class AppSettingsService extends ChangeNotifier {
     _settings = newSettings;
     notifyListeners();
 
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = jsonEncode(_settings.toJson());
     await prefs.setString(_settingsKey, jsonStr);
   }

lib/services/map_marker_service.dart

@@ -1,16 +1,16 @@
-import 'package:shared_preferences/shared_preferences.dart';
+import '../storage/prefs_manager.dart';
 
 class MapMarkerService {
   static const String _removedKey = 'map_removed_marker_ids';
 
   Future<Set<String>> loadRemovedIds() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final items = prefs.getStringList(_removedKey) ?? const [];
     return items.toSet();
   }
 
   Future<void> saveRemovedIds(Set<String> ids) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     await prefs.setStringList(_removedKey, ids.toList());
   }
 }

lib/services/path_history_service.dart

@@ -10,6 +10,10 @@ class PathHistoryService extends ChangeNotifier {
   final Map<String, int> _autoRotationIndex = {};
   final Map<String, _FloodStats> _floodStats = {};
 
+  // LRU cache eviction tracking
+  static const int _maxCachedContacts = 50;
+  final List<String> _cacheAccessOrder = [];
+
   static const int _maxHistoryEntries = 100;
   static const int _autoRotationTopCount = 3;
 
@@ -91,6 +95,8 @@ class PathHistoryService extends ChangeNotifier {
       return const PathSelection(pathBytes: [], hopCount: -1, useFlood: true);
     }
 
+    _trackAccess(contactPubKeyHex);
+
     final selections = ranked
         .map((path) => PathSelection(
               pathBytes: path.pathBytes,
@@ -208,6 +214,8 @@ class PathHistoryService extends ChangeNotifier {
     );
 
     _cache[contactPubKeyHex] = updatedHistory;
+    _trackAccess(contactPubKeyHex);
+    _evictIfNeeded();
     _storage.savePathHistory(contactPubKeyHex, updatedHistory);
 
     notifyListeners();
@@ -216,12 +224,15 @@ class PathHistoryService extends ChangeNotifier {
   List<PathRecord> getRecentPaths(String contactPubKeyHex) {
     final history = _cache[contactPubKeyHex];
     if (history != null) {
+      _trackAccess(contactPubKeyHex);
       return history.recentPaths;
     }
 
     _loadHistoryFromStorage(contactPubKeyHex).then((loaded) {
       if (loaded != null) {
         _cache[contactPubKeyHex] = loaded;
+        _trackAccess(contactPubKeyHex);
+        _evictIfNeeded();
         notifyListeners();
       }
     });
@@ -236,16 +247,23 @@ class PathHistoryService extends ChangeNotifier {
 
   PathRecord? getFastestPath(String contactPubKeyHex) {
     final history = _cache[contactPubKeyHex];
+    if (history != null) {
+      _trackAccess(contactPubKeyHex);
+    }
     return history?.fastest;
   }
 
   PathRecord? getMostRecentPath(String contactPubKeyHex) {
     final history = _cache[contactPubKeyHex];
+    if (history != null) {
+      _trackAccess(contactPubKeyHex);
+    }
     return history?.mostRecent;
   }
 
   Future<void> clearPathHistory(String contactPubKeyHex) async {
     _cache.remove(contactPubKeyHex);
+    _cacheAccessOrder.remove(contactPubKeyHex);
     _autoRotationIndex.remove(contactPubKeyHex);
     _floodStats.remove(contactPubKeyHex);
     await _storage.clearPathHistory(contactPubKeyHex);
@@ -314,6 +332,20 @@ class PathHistoryService extends ChangeNotifier {
     final stats = _floodStats.putIfAbsent(contactPubKeyHex, () => _FloodStats());
     stats.lastUsed = DateTime.now();
   }
+
+  void _trackAccess(String contactPubKeyHex) {
+    _cacheAccessOrder.remove(contactPubKeyHex);
+    _cacheAccessOrder.add(contactPubKeyHex);
+  }
+
+  void _evictIfNeeded() {
+    while (_cache.length > _maxCachedContacts && _cacheAccessOrder.isNotEmpty) {
+      final oldest = _cacheAccessOrder.removeAt(0);
+      _cache.remove(oldest);
+      _autoRotationIndex.remove(oldest);
+      _floodStats.remove(oldest);
+    }
+  }
 }
 
 class _FloodStats {

lib/services/storage_service.dart

@@ -1,6 +1,6 @@
 import 'dart:convert';
-import 'package:shared_preferences/shared_preferences.dart';
 import '../models/path_history.dart';
+import '../storage/prefs_manager.dart';
 
 class StorageService {
   static const String _pathHistoryPrefix = 'path_history_';
@@ -9,14 +9,14 @@ class StorageService {
 
   Future<void> savePathHistory(
       String contactPubKeyHex, ContactPathHistory history) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_pathHistoryPrefix$contactPubKeyHex';
     final jsonStr = jsonEncode(history.toJson());
     await prefs.setString(key, jsonStr);
   }
 
   Future<ContactPathHistory?> loadPathHistory(String contactPubKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_pathHistoryPrefix$contactPubKeyHex';
     final jsonStr = prefs.getString(key);
 
@@ -31,13 +31,13 @@ class StorageService {
   }
 
   Future<void> clearPathHistory(String contactPubKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_pathHistoryPrefix$contactPubKeyHex';
     await prefs.remove(key);
   }
 
   Future<void> clearAllPathHistories() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final keys = prefs.getKeys();
     final pathHistoryKeys =
         keys.where((key) => key.startsWith(_pathHistoryPrefix));
@@ -48,7 +48,7 @@ class StorageService {
   }
 
   Future<Map<String, String>> loadPendingMessages() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_pendingMessagesKey);
 
     if (jsonStr == null) return {};
@@ -62,20 +62,20 @@ class StorageService {
   }
 
   Future<void> savePendingMessages(Map<String, String> pending) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = jsonEncode(pending);
     await prefs.setString(_pendingMessagesKey, jsonStr);
   }
 
   Future<void> clearPendingMessages() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     await prefs.remove(_pendingMessagesKey);
   }
 
   /// Save a repeater password by public key hex
   Future<void> saveRepeaterPassword(
       String repeaterPubKeyHex, String password) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final passwords = await loadRepeaterPasswords();
     passwords[repeaterPubKeyHex] = password;
     final jsonStr = jsonEncode(passwords);
@@ -84,7 +84,7 @@ class StorageService {
 
   /// Load all saved repeater passwords (map of pubKeyHex -> password)
   Future<Map<String, String>> loadRepeaterPasswords() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_repeaterPasswordsKey);
 
     if (jsonStr == null) return {};
@@ -105,7 +105,7 @@ class StorageService {
 
   /// Remove a saved repeater password
   Future<void> removeRepeaterPassword(String repeaterPubKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final passwords = await loadRepeaterPasswords();
     passwords.remove(repeaterPubKeyHex);
     final jsonStr = jsonEncode(passwords);
@@ -114,7 +114,7 @@ class StorageService {
 
   /// Clear all saved repeater passwords
   Future<void> clearAllRepeaterPasswords() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     await prefs.remove(_repeaterPasswordsKey);
   }
 }

lib/services/voice_message_service.dart

@@ -1,220 +0,0 @@
-import 'dart:convert';
-import 'dart:io';
-import 'dart:typed_data';
-
-import 'package:path/path.dart' as path;
-import 'package:path_provider/path_provider.dart';
-
-import 'codec2_ffi.dart';
-
-class VoiceMessageService {
-  static const int sampleRate = 8000;
-  static const int channels = 1;
-  static const int bitsPerSample = 16;
-  static const int maxRecordSeconds = 5;
-  static const int chunkRawBytes = 90;
-  static const String codecName = 'codec2_1300';
-  static const String chunkPrefix = 'V1|';
-
-  static final VoiceMessageService instance = VoiceMessageService._();
-
-  VoiceMessageService._();
-
-  Future<Directory> ensureVoiceDir() async {
-    final docs = await getApplicationDocumentsDirectory();
-    final dir = Directory(path.join(docs.path, 'voice'));
-    if (!await dir.exists()) {
-      await dir.create(recursive: true);
-    }
-    return dir;
-  }
-
-  String buildVoiceFileName({
-    required String senderKeyHex,
-    required int timestampSeconds,
-    bool outgoing = false,
-  }) {
-    final suffix = outgoing ? 'out' : 'in';
-    return 'voice_${senderKeyHex}_${timestampSeconds}_$suffix.wav';
-  }
-
-  List<String> buildVoiceChunks(Uint8List codec2Bytes) {
-    if (codec2Bytes.isEmpty) return [];
-    final chunks = <Uint8List>[];
-    for (var offset = 0; offset < codec2Bytes.length; offset += chunkRawBytes) {
-      final end = (offset + chunkRawBytes).clamp(0, codec2Bytes.length).toInt();
-      chunks.add(Uint8List.fromList(codec2Bytes.sublist(offset, end)));
-    }
-    final count = chunks.length;
-    return List<String>.generate(count, (index) {
-      final encoded = _base64UrlEncodeNoPad(chunks[index]);
-      return '$chunkPrefix$index/$count|$encoded';
-    });
-  }
-
-  VoiceChunk? tryParseChunk(String text) {
-    final trimmed = text.trim();
-    if (!trimmed.startsWith(chunkPrefix)) return null;
-    final match = RegExp(r'^V1\|(\d+)/(\d+)\|([A-Za-z0-9_-]+)$').firstMatch(trimmed);
-    if (match == null) return null;
-    final idx = int.tryParse(match.group(1) ?? '');
-    final count = int.tryParse(match.group(2) ?? '');
-    final payload = match.group(3);
-    if (idx == null || count == null || payload == null) return null;
-    if (idx < 0 || count <= 0 || idx >= count) return null;
-    try {
-      final bytes = _base64UrlDecode(payload);
-      return VoiceChunk(index: idx, count: count, bytes: bytes);
-    } catch (_) {
-      return null;
-    }
-  }
-
-  Uint8List encodePcmToCodec2(Uint8List pcmBytes) {
-    final session = Codec2Ffi.instance.createSession();
-    try {
-      final samplesPerFrame = session.samplesPerFrameValue;
-      final pcmSamples = _toInt16(pcmBytes);
-      final frameCount = (pcmSamples.length + samplesPerFrame - 1) ~/ samplesPerFrame;
-      final builder = BytesBuilder(copy: false);
-
-      for (var frameIndex = 0; frameIndex < frameCount; frameIndex++) {
-        final start = frameIndex * samplesPerFrame;
-        final end = (start + samplesPerFrame).clamp(0, pcmSamples.length).toInt();
-        final frame = Int16List(samplesPerFrame);
-        final copyLen = end - start;
-        if (copyLen > 0) {
-          frame.setRange(0, copyLen, pcmSamples.sublist(start, end));
-        }
-        final encoded = session.encodePcmFrame(frame);
-        builder.add(encoded);
-      }
-
-      return builder.takeBytes();
-    } finally {
-      session.dispose();
-    }
-  }
-
-  Uint8List decodeCodec2ToPcm(Uint8List codec2Bytes) {
-    final session = Codec2Ffi.instance.createSession();
-    try {
-      final bytesPerFrame = session.bytesPerFrameValue;
-      if (bytesPerFrame <= 0) return Uint8List(0);
-      final frameCount = codec2Bytes.length ~/ bytesPerFrame;
-      final builder = BytesBuilder(copy: false);
-
-      for (var frameIndex = 0; frameIndex < frameCount; frameIndex++) {
-        final start = frameIndex * bytesPerFrame;
-        final frameBytes = codec2Bytes.sublist(start, start + bytesPerFrame);
-        final decoded = session.decodeCodecFrame(frameBytes);
-        builder.add(Uint8List.view(
-          decoded.buffer,
-          decoded.offsetInBytes,
-          decoded.lengthInBytes,
-        ));
-      }
-
-      return builder.takeBytes();
-    } finally {
-      session.dispose();
-    }
-  }
-
-  int durationMsForCodec2Bytes(Uint8List codec2Bytes) {
-    final session = Codec2Ffi.instance.createSession();
-    try {
-      final bytesPerFrame = session.bytesPerFrameValue;
-      final samplesPerFrame = session.samplesPerFrameValue;
-      if (bytesPerFrame <= 0 || samplesPerFrame <= 0) return 0;
-      final frameCount = codec2Bytes.length ~/ bytesPerFrame;
-      final frameDurationMs = (samplesPerFrame * 1000 / sampleRate).round();
-      return frameCount * frameDurationMs;
-    } finally {
-      session.dispose();
-    }
-  }
-
-  Future<String> writeWavFile({
-    required Uint8List pcmBytes,
-    required String fileName,
-  }) async {
-    final dir = await ensureVoiceDir();
-    final filePath = path.join(dir.path, fileName);
-    final wavHeader = _buildWavHeader(
-      pcmDataSize: pcmBytes.length,
-      sampleRate: sampleRate,
-      channels: channels,
-      bitsPerSample: bitsPerSample,
-    );
-    final file = File(filePath);
-    final builder = BytesBuilder(copy: false);
-    builder.add(wavHeader);
-    builder.add(pcmBytes);
-    await file.writeAsBytes(builder.takeBytes(), flush: true);
-    return filePath;
-  }
-
-  Uint8List _buildWavHeader({
-    required int pcmDataSize,
-    required int sampleRate,
-    required int channels,
-    required int bitsPerSample,
-  }) {
-    final byteRate = sampleRate * channels * (bitsPerSample ~/ 8);
-    final blockAlign = channels * (bitsPerSample ~/ 8);
-    final buffer = BytesBuilder(copy: false);
-    buffer.add(ascii.encode('RIFF'));
-    buffer.add(_le32(36 + pcmDataSize));
-    buffer.add(ascii.encode('WAVE'));
-    buffer.add(ascii.encode('fmt '));
-    buffer.add(_le32(16));
-    buffer.add(_le16(1));
-    buffer.add(_le16(channels));
-    buffer.add(_le32(sampleRate));
-    buffer.add(_le32(byteRate));
-    buffer.add(_le16(blockAlign));
-    buffer.add(_le16(bitsPerSample));
-    buffer.add(ascii.encode('data'));
-    buffer.add(_le32(pcmDataSize));
-    return buffer.takeBytes();
-  }
-
-  Uint8List _le16(int value) {
-    final data = ByteData(2)..setUint16(0, value, Endian.little);
-    return data.buffer.asUint8List();
-  }
-
-  Uint8List _le32(int value) {
-    final data = ByteData(4)..setUint32(0, value, Endian.little);
-    return data.buffer.asUint8List();
-  }
-
-  Int16List _toInt16(Uint8List bytes) {
-    final evenLength = bytes.lengthInBytes - (bytes.lengthInBytes % 2);
-    if (evenLength <= 0) return Int16List(0);
-    return Int16List.view(bytes.buffer, bytes.offsetInBytes, evenLength ~/ 2);
-  }
-
-  String _base64UrlEncodeNoPad(Uint8List bytes) {
-    return base64Url.encode(bytes).replaceAll('=', '');
-  }
-
-  Uint8List _base64UrlDecode(String encoded) {
-    final paddedLength = (encoded.length + 3) ~/ 4 * 4;
-    final padded = encoded.padRight(paddedLength, '=');
-    return base64Url.decode(padded);
-  }
-}
-
-class VoiceChunk {
-  final int index;
-  final int count;
-  final Uint8List bytes;
-
-  VoiceChunk({
-    required this.index,
-    required this.count,
-    required this.bytes,
-  });
-}

lib/storage/channel_message_store.dart

@@ -1,15 +1,15 @@
 import 'dart:convert';
 import 'dart:typed_data';
-import 'package:shared_preferences/shared_preferences.dart';
 import '../models/channel_message.dart';
 import '../helpers/smaz.dart';
+import 'prefs_manager.dart';
 
 class ChannelMessageStore {
   static const String _keyPrefix = 'channel_messages_';
 
   /// Save messages for a specific channel
   Future<void> saveChannelMessages(int channelIndex, List<ChannelMessage> messages) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$channelIndex';
 
     // Convert messages to JSON
@@ -21,7 +21,7 @@ class ChannelMessageStore {
 
   /// Load messages for a specific channel
   Future<List<ChannelMessage>> loadChannelMessages(int channelIndex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$channelIndex';
 
     final jsonString = prefs.getString(key);
@@ -38,14 +38,14 @@ class ChannelMessageStore {
 
   /// Clear messages for a specific channel
   Future<void> clearChannelMessages(int channelIndex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$channelIndex';
     await prefs.remove(key);
   }
 
   /// Clear all channel messages
   Future<void> clearAllChannelMessages() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final keys = prefs.getKeys().where((k) => k.startsWith(_keyPrefix));
     for (var key in keys) {
       await prefs.remove(key);
@@ -67,6 +67,10 @@ class ChannelMessageStore {
       'pathBytes': base64Encode(msg.pathBytes),
       'pathVariants': msg.pathVariants.map(base64Encode).toList(),
       'repeats': msg.repeats.map(_repeatToJson).toList(),
+      'messageId': msg.messageId,
+      'replyToMessageId': msg.replyToMessageId,
+      'replyToSenderName': msg.replyToSenderName,
+      'replyToText': msg.replyToText,
     };
   }
 
@@ -96,6 +100,10 @@ class ChannelMessageStore {
               .toList() ??
           const [],
       channelIndex: json['channelIndex'] as int?,
+      messageId: json['messageId'] as String?,
+      replyToMessageId: json['replyToMessageId'] as String?,
+      replyToSenderName: json['replyToSenderName'] as String?,
+      replyToText: json['replyToText'] as String?,
     );
   }
 

lib/storage/channel_order_store.dart

@@ -1,16 +1,16 @@
 import 'dart:convert';
-import 'package:shared_preferences/shared_preferences.dart';
+import 'prefs_manager.dart';
 
 class ChannelOrderStore {
   static const String _key = 'channel_order';
 
   Future<void> saveChannelOrder(List<int> order) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     await prefs.setString(_key, jsonEncode(order));
   }
 
   Future<List<int>> loadChannelOrder() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final raw = prefs.getString(_key);
     if (raw == null || raw.isEmpty) return [];
     try {

lib/storage/channel_settings_store.dart

@@ -1,16 +1,16 @@
-import 'package:shared_preferences/shared_preferences.dart';
+import 'prefs_manager.dart';
 
 class ChannelSettingsStore {
   static const String _smazKeyPrefix = 'channel_smaz_';
 
   Future<bool> loadSmazEnabled(int channelIndex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_smazKeyPrefix$channelIndex';
     return prefs.getBool(key) ?? false;
   }
 
   Future<void> saveSmazEnabled(int channelIndex, bool enabled) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_smazKeyPrefix$channelIndex';
     await prefs.setBool(key, enabled);
   }

lib/storage/contact_group_store.dart

@@ -1,12 +1,12 @@
 import 'dart:convert';
-import 'package:shared_preferences/shared_preferences.dart';
 import '../models/contact_group.dart';
+import 'prefs_manager.dart';
 
 class ContactGroupStore {
   static const String _key = 'contact_groups';
 
   Future<List<ContactGroup>> loadGroups() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final raw = prefs.getString(_key);
     if (raw == null || raw.isEmpty) return [];
 
@@ -25,7 +25,7 @@ class ContactGroupStore {
   }
 
   Future<void> saveGroups(List<ContactGroup> groups) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final encoded = jsonEncode(groups.map((group) => group.toJson()).toList());
     await prefs.setString(_key, encoded);
   }

lib/storage/contact_settings_store.dart

@@ -1,16 +1,16 @@
-import 'package:shared_preferences/shared_preferences.dart';
+import 'prefs_manager.dart';
 
 class ContactSettingsStore {
   static const String _smazKeyPrefix = 'contact_smaz_';
 
   Future<bool> loadSmazEnabled(String contactKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_smazKeyPrefix$contactKeyHex';
     return prefs.getBool(key) ?? false;
   }
 
   Future<void> saveSmazEnabled(String contactKeyHex, bool enabled) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_smazKeyPrefix$contactKeyHex';
     await prefs.setBool(key, enabled);
   }

lib/storage/contact_store.dart

@@ -1,15 +1,14 @@
 import 'dart:convert';
 import 'dart:typed_data';
 
-import 'package:shared_preferences/shared_preferences.dart';
-
 import '../models/contact.dart';
+import 'prefs_manager.dart';
 
 class ContactStore {
   static const String _key = 'contacts';
 
   Future<List<Contact>> loadContacts() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_key);
     if (jsonStr == null) return [];
 
@@ -22,7 +21,7 @@ class ContactStore {
   }
 
   Future<void> saveContacts(List<Contact> contacts) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonList = contacts.map(_toJson).toList();
     await prefs.setString(_key, jsonEncode(jsonList));
   }

lib/storage/message_store.dart

@@ -1,21 +1,21 @@
 import 'dart:convert';
 import 'dart:typed_data';
-import 'package:shared_preferences/shared_preferences.dart';
 import '../models/message.dart';
 import '../helpers/smaz.dart';
+import 'prefs_manager.dart';
 
 class MessageStore {
   static const String _keyPrefix = 'messages_';
 
   Future<void> saveMessages(String contactKeyHex, List<Message> messages) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$contactKeyHex';
     final jsonList = messages.map(_messageToJson).toList();
     await prefs.setString(key, jsonEncode(jsonList));
   }
 
   Future<List<Message>> loadMessages(String contactKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$contactKeyHex';
     final jsonString = prefs.getString(key);
     if (jsonString == null) return [];
@@ -29,7 +29,7 @@ class MessageStore {
   }
 
   Future<void> clearMessages(String contactKeyHex) async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final key = '$_keyPrefix$contactKeyHex';
     await prefs.remove(key);
   }
@@ -41,10 +41,6 @@ class MessageStore {
       'timestamp': msg.timestamp.millisecondsSinceEpoch,
       'isOutgoing': msg.isOutgoing,
       'isCli': msg.isCli,
-      'isVoice': msg.isVoice,
-      'voicePath': msg.voicePath,
-      'voiceDurationMs': msg.voiceDurationMs,
-      'voiceCodec': msg.voiceCodec,
       'status': msg.status.index,
       'messageId': msg.messageId,
       'retryCount': msg.retryCount,
@@ -69,10 +65,6 @@ class MessageStore {
       timestamp: DateTime.fromMillisecondsSinceEpoch(json['timestamp'] as int),
       isOutgoing: json['isOutgoing'] as bool,
       isCli: isCli,
-      isVoice: json['isVoice'] as bool? ?? false,
-      voicePath: json['voicePath'] as String?,
-      voiceDurationMs: json['voiceDurationMs'] as int?,
-      voiceCodec: json['voiceCodec'] as String?,
       status: MessageStatus.values[json['status'] as int],
       messageId: json['messageId'] as String?,
       retryCount: json['retryCount'] as int? ?? 0,

lib/storage/prefs_manager.dart

@@ -0,0 +1,33 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+/// Singleton wrapper for SharedPreferences to avoid redundant getInstance() calls.
+///
+/// BEFORE: Every storage operation called SharedPreferences.getInstance()
+/// AFTER: Single getInstance() on app startup, reused throughout lifecycle
+///
+/// This eliminates 30+ redundant platform channel calls across the app.
+class PrefsManager {
+  PrefsManager._();
+
+  static SharedPreferences? _instance;
+
+  /// Initialize the cached instance. Call this once during app startup in main().
+  static Future<void> initialize() async {
+    _instance ??= await SharedPreferences.getInstance();
+  }
+
+  /// Get the cached SharedPreferences instance.
+  /// Throws StateError if initialize() hasn't been called.
+  static SharedPreferences get instance {
+    if (_instance == null) {
+      throw StateError(
+          'PrefsManager not initialized. Call PrefsManager.initialize() in main() before use.');
+    }
+    return _instance!;
+  }
+
+  /// For testing: reset the instance
+  static void reset() {
+    _instance = null;
+  }
+}

lib/storage/unread_store.dart

@@ -1,13 +1,30 @@
+import 'dart:async';
 import 'dart:convert';
 
-import 'package:shared_preferences/shared_preferences.dart';
+import 'prefs_manager.dart';
 
+/// Storage for unread message tracking with debounced writes to reduce I/O.
 class UnreadStore {
   static const String _contactLastReadKey = 'contact_last_read';
   static const String _channelLastReadKey = 'channel_last_read';
 
+  // Debounce timers to batch rapid writes
+  Timer? _contactSaveTimer;
+  Timer? _channelSaveTimer;
+  static const Duration _saveDebounceDuration = Duration(milliseconds: 500);
+
+  // Pending write data
+  Map<String, int>? _pendingContactLastRead;
+  Map<int, int>? _pendingChannelLastRead;
+
+  /// Dispose timers when no longer needed
+  void dispose() {
+    _contactSaveTimer?.cancel();
+    _channelSaveTimer?.cancel();
+  }
+
   Future<Map<String, int>> loadContactLastRead() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_contactLastReadKey);
     if (jsonStr == null) return {};
 
@@ -19,14 +36,24 @@ class UnreadStore {
     }
   }
 
-  Future<void> saveContactLastRead(Map<String, int> lastReadMs) async {
-    final prefs = await SharedPreferences.getInstance();
-    final jsonStr = jsonEncode(lastReadMs);
-    await prefs.setString(_contactLastReadKey, jsonStr);
+  /// Save contact last read timestamps with debouncing.
+  /// Writes are delayed by 500ms and batched to reduce I/O operations.
+  void saveContactLastRead(Map<String, int> lastReadMs) {
+    _pendingContactLastRead = lastReadMs;
+
+    // Cancel existing timer
+    _contactSaveTimer?.cancel();
+
+    // Schedule new write
+    _contactSaveTimer = Timer(_saveDebounceDuration, () async {
+      if (_pendingContactLastRead != null) {
+        await _flushContactLastRead();
+      }
+    });
   }
 
   Future<Map<int, int>> loadChannelLastRead() async {
-    final prefs = await SharedPreferences.getInstance();
+    final prefs = PrefsManager.instance;
     final jsonStr = prefs.getString(_channelLastReadKey);
     if (jsonStr == null) return {};
 
@@ -38,10 +65,48 @@ class UnreadStore {
     }
   }
 
-  Future<void> saveChannelLastRead(Map<int, int> lastReadMs) async {
-    final prefs = await SharedPreferences.getInstance();
-    final asString = lastReadMs.map((key, value) => MapEntry(key.toString(), value));
+  /// Save channel last read timestamps with debouncing.
+  /// Writes are delayed by 500ms and batched to reduce I/O operations.
+  void saveChannelLastRead(Map<int, int> lastReadMs) {
+    _pendingChannelLastRead = lastReadMs;
+
+    _channelSaveTimer?.cancel();
+
+    _channelSaveTimer = Timer(_saveDebounceDuration, () async {
+      if (_pendingChannelLastRead != null) {
+        await _flushChannelLastRead();
+      }
+    });
+  }
+
+  Future<void> _flushContactLastRead() async {
+    if (_pendingContactLastRead == null) return;
+
+    final prefs = PrefsManager.instance;
+    final jsonStr = jsonEncode(_pendingContactLastRead);
+    await prefs.setString(_contactLastReadKey, jsonStr);
+    _pendingContactLastRead = null;
+  }
+
+  Future<void> _flushChannelLastRead() async {
+    if (_pendingChannelLastRead == null) return;
+
+    final prefs = PrefsManager.instance;
+    final asString =
+        _pendingChannelLastRead!.map((key, value) => MapEntry(key.toString(), value));
     final jsonStr = jsonEncode(asString);
     await prefs.setString(_channelLastReadKey, jsonStr);
+    _pendingChannelLastRead = null;
+  }
+
+  /// Immediately flush pending writes (call before app termination or disposal)
+  Future<void> flush() async {
+    _contactSaveTimer?.cancel();
+    _channelSaveTimer?.cancel();
+
+    await Future.wait([
+      _flushContactLastRead(),
+      _flushChannelLastRead(),
+    ]);
   }
 }

lib/utils/dialog_utils.dart

@@ -0,0 +1,34 @@
+import 'package:flutter/material.dart';
+import '../connector/meshcore_connector.dart';
+
+/// Shows a confirmation dialog before disconnecting from the device.
+/// Returns true if user confirmed and disconnect completed, false otherwise.
+Future<bool> showDisconnectDialog(
+  BuildContext context,
+  MeshCoreConnector connector,
+) async {
+  final confirmed = await showDialog<bool>(
+    context: context,
+    builder: (context) => AlertDialog(
+      title: const Text('Disconnect'),
+      content: const Text(
+          'Are you sure you want to disconnect from this device?'),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.pop(context, false),
+          child: const Text('Cancel'),
+        ),
+        TextButton(
+          onPressed: () => Navigator.pop(context, true),
+          child: const Text('Disconnect'),
+        ),
+      ],
+    ),
+  );
+
+  if (confirmed == true) {
+    await connector.disconnect();
+    return true;
+  }
+  return false;
+}

lib/utils/disconnect_navigation_mixin.dart

@@ -0,0 +1,20 @@
+import 'package:flutter/material.dart';
+import '../connector/meshcore_connector.dart';
+
+/// Mixin that automatically navigates back to scanner when disconnected.
+/// Use in State classes for screens that require active connection.
+mixin DisconnectNavigationMixin<T extends StatefulWidget> on State<T> {
+  /// Call this in your Widget build method to enable auto-navigation.
+  /// Returns true if still connected, false if navigation was triggered.
+  bool checkConnectionAndNavigate(MeshCoreConnector connector) {
+    if (!connector.isConnected) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted) {
+          Navigator.popUntil(context, (route) => route.isFirst);
+        }
+      });
+      return false;
+    }
+    return true;
+  }
+}

lib/widgets/empty_state.dart

@@ -0,0 +1,46 @@
+import 'package:flutter/material.dart';
+
+/// A centered empty state display with icon, title, and optional subtitle/action.
+class EmptyState extends StatelessWidget {
+  final IconData icon;
+  final String title;
+  final String? subtitle;
+  final Widget? action;
+
+  const EmptyState({
+    super.key,
+    required this.icon,
+    required this.title,
+    this.subtitle,
+    this.action,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisAlignment: MainAxisAlignment.center,
+        children: [
+          Icon(icon, size: 64, color: Colors.grey[400]),
+          const SizedBox(height: 16),
+          Text(
+            title,
+            style: TextStyle(fontSize: 16, color: Colors.grey[600]),
+          ),
+          if (subtitle != null) ...[
+            const SizedBox(height: 8),
+            Text(
+              subtitle!,
+              style: TextStyle(fontSize: 14, color: Colors.grey[500]),
+              textAlign: TextAlign.center,
+            ),
+          ],
+          if (action != null) ...[
+            const SizedBox(height: 24),
+            action!,
+          ],
+        ],
+      ),
+    );
+  }
+}

lib/widgets/voice_message.dart

@@ -1,134 +0,0 @@
-import 'dart:async';
-
-import 'package:flutter/material.dart';
-import 'package:media_kit_fork/media_kit_fork.dart';
-
-import '../models/message.dart';
-
-class VoiceMessageBubble extends StatefulWidget {
-  final Message message;
-  final Color backgroundColor;
-  final Color textColor;
-  final Color metaColor;
-  final bool isOutgoing;
-
-  const VoiceMessageBubble({
-    super.key,
-    required this.message,
-    required this.backgroundColor,
-    required this.textColor,
-    required this.metaColor,
-    required this.isOutgoing,
-  });
-
-  @override
-  State<VoiceMessageBubble> createState() => _VoiceMessageBubbleState();
-}
-
-class _VoiceMessageBubbleState extends State<VoiceMessageBubble> {
-  late final Player _player;
-  StreamSubscription<Duration>? _durationSubscription;
-  StreamSubscription<bool>? _completeSubscription;
-  Duration _duration = Duration.zero;
-
-  @override
-  void initState() {
-    super.initState();
-    _player = Player();
-    final voicePath = widget.message.voicePath;
-    if (voicePath != null && voicePath.isNotEmpty) {
-      _player.open(Media(Uri.file(voicePath).toString()), play: false);
-    }
-    _durationSubscription = _player.stream.duration.listen((value) {
-      if (!mounted) return;
-      if (value > Duration.zero && value != _duration) {
-        setState(() {
-          _duration = value;
-        });
-      }
-    });
-    _completeSubscription = _player.stream.completed.listen((completed) {
-      if (!completed) return;
-      _player.seek(Duration.zero);
-      _player.pause();
-    });
-  }
-
-  @override
-  void dispose() {
-    _durationSubscription?.cancel();
-    _completeSubscription?.cancel();
-    _player.dispose();
-    super.dispose();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    final hasAudio = widget.message.voicePath != null && widget.message.voicePath!.isNotEmpty;
-    final fallbackDuration = Duration(milliseconds: widget.message.voiceDurationMs ?? 0);
-    final displayDuration = _duration > Duration.zero ? _duration : fallbackDuration;
-
-    return StreamBuilder<bool>(
-      stream: _player.stream.playing,
-      initialData: false,
-      builder: (context, playingSnapshot) {
-        final isPlaying = playingSnapshot.data ?? false;
-        return Column(
-          crossAxisAlignment: CrossAxisAlignment.start,
-          children: [
-            Row(
-              children: [
-                IconButton(
-                  icon: Icon(isPlaying ? Icons.pause : Icons.play_arrow),
-                  color: widget.textColor,
-                  onPressed: hasAudio
-                      ? () {
-                          if (isPlaying) {
-                            _player.pause();
-                          } else {
-                            _player.play();
-                          }
-                        }
-                      : null,
-                ),
-                Expanded(
-                  child: StreamBuilder<Duration>(
-                    stream: _player.stream.position,
-                    initialData: Duration.zero,
-                    builder: (context, positionSnapshot) {
-                      final position = positionSnapshot.data ?? Duration.zero;
-                      final progress = displayDuration.inMilliseconds > 0
-                          ? position.inMilliseconds / displayDuration.inMilliseconds
-                          : 0.0;
-                      return LinearProgressIndicator(
-                        value: progress.clamp(0.0, 1.0),
-                        backgroundColor: widget.metaColor.withValues(alpha: 0.2),
-                        valueColor: AlwaysStoppedAnimation<Color>(widget.textColor),
-                        minHeight: 4,
-                      );
-                    },
-                  ),
-                ),
-                const SizedBox(width: 8),
-                Text(
-                  _formatDuration(displayDuration),
-                  style: TextStyle(
-                    color: widget.metaColor,
-                    fontSize: 11,
-                  ),
-                ),
-              ],
-            ),
-          ],
-        );
-      },
-    );
-  }
-
-  String _formatDuration(Duration duration) {
-    final totalSeconds = duration.inSeconds;
-    final minutes = totalSeconds ~/ 60;
-    final seconds = totalSeconds % 60;
-    return '${minutes.toString().padLeft(2, '0')}:${seconds.toString().padLeft(2, '0')}';
-  }
-}