fix: model name inconsistencies

lib/core/providers/app_providers.dart

@@ -333,7 +333,7 @@ final defaultModelAutoSelectionProvider = Provider<void>((ref) {
     final desired = next.defaultModel;
     if (desired == null || desired.isEmpty) return;
 
-    // Resolve the desired model against available models
+    // Resolve the desired model against available models (by ID only)
     Future(() async {
       try {
         // Prefer already-loaded models to avoid unnecessary fetches
@@ -346,14 +346,10 @@ final defaultModelAutoSelectionProvider = Provider<void>((ref) {
         }
         Model? selected;
         try {
-          selected = models.firstWhere(
+          selected = models.firstWhere((model) => model.id == desired);
-            (model) =>
+        } catch (_) {
-                model.id == desired ||
+          selected = null;
-                model.name == desired ||
+        }
-                model.id.contains(desired) ||
-                model.name.contains(desired),
-          );
-        } catch (_) {}
 
         // Fallback: keep current selection or pick first available
         selected ??= ref.read(selectedModelProvider) ??
@@ -362,7 +358,7 @@ final defaultModelAutoSelectionProvider = Provider<void>((ref) {
         if (selected != null) {
           ref.read(selectedModelProvider.notifier).state = selected;
           foundation.debugPrint(
-            'DEBUG: Auto-applied default model from settings: ${selected.name}',
+            'DEBUG: Auto-applied default model (by ID): ${selected.name}',
           );
         }
       } catch (e) {
@@ -669,29 +665,43 @@ final defaultModelProvider = FutureProvider<Model?>((ref) async {
 
     Model? selectedModel;
 
-    // First check user's preferred default model
+    // First check user's preferred default model (ID only). If an older
+    // name-based value is found, migrate it once to the correct ID.
     final userSettings = ref.read(appSettingsProvider);
     final userDefaultModelId = userSettings.defaultModel;
 
     if (userDefaultModelId != null && userDefaultModelId.isNotEmpty) {
       try {
-        selectedModel = models.firstWhere(
+        // Exact ID match only
-          (model) =>
+        selectedModel =
-              model.id == userDefaultModelId ||
+            models.firstWhere((model) => model.id == userDefaultModelId);
-              model.name == userDefaultModelId ||
-              model.id.contains(userDefaultModelId) ||
-              model.name.contains(userDefaultModelId),
-        );
         foundation.debugPrint(
-          'DEBUG: Found user default model: ${selectedModel.name}',
+          'DEBUG: Found user default model by ID: ${selectedModel.name}',
         );
       } catch (e) {
+        // Attempt a one-time migration if the stored value was a model name
+        // from older versions. Only migrate on exact, unique name match.
+        final nameMatches =
+            models.where((m) => m.name == userDefaultModelId).toList();
+        if (nameMatches.length == 1) {
+          selectedModel = nameMatches.first;
           foundation.debugPrint(
-          'DEBUG: User default model "$userDefaultModelId" not found in available models',
+            'DEBUG: Migrating user default model name to ID: '
+            '${nameMatches.first.name} -> ${nameMatches.first.id}',
+          );
+          // Persist the migrated ID
+          await ref
+              .read(appSettingsProvider.notifier)
+              .setDefaultModel(nameMatches.first.id);
+        } else {
+          foundation.debugPrint(
+            'DEBUG: User default model "$userDefaultModelId" not found by ID and '
+            'no unique name match. Ignoring.',
           );
           selectedModel = null; // Will fall back to server default or first model
         }
       }
+    }
 
     // If no user default or user default not found, try server's default model
     if (selectedModel == null) {
@@ -699,24 +709,30 @@ final defaultModelProvider = FutureProvider<Model?>((ref) async {
         final defaultModelId = await api.getDefaultModel();
 
         if (defaultModelId != null && defaultModelId.isNotEmpty) {
-          // Find the model that matches the default model ID
+          // Find the model that matches the default model ID (ID only)
           try {
-            selectedModel = models.firstWhere(
+            selectedModel =
-              (model) =>
+                models.firstWhere((model) => model.id == defaultModelId);
-                  model.id == defaultModelId ||
-                  model.name == defaultModelId ||
-                  model.id.contains(defaultModelId) ||
-                  model.name.contains(defaultModelId),
-            );
             foundation.debugPrint(
-              'DEBUG: Found server default model: ${selectedModel.name}',
+              'DEBUG: Found server default model by ID: ${selectedModel.name}',
             );
           } catch (e) {
+            // If server returned a name instead of ID, attempt exact name match.
+            final byName = models.where((m) => m.name == defaultModelId).toList();
+            if (byName.length == 1) {
+              selectedModel = byName.first;
               foundation.debugPrint(
-              'DEBUG: Server default model "$defaultModelId" not found in available models',
+                'DEBUG: Server default "$defaultModelId" matched by name; '
+                'selected ${selectedModel.name} (${selectedModel.id})',
+              );
+            } else {
+              foundation.debugPrint(
+                'DEBUG: Server default model "$defaultModelId" not found by ID; '
+                'falling back to first available',
               );
               selectedModel = models.first;
             }
+          }
         } else {
           // No server default, use first available model
           selectedModel = models.first;

lib/features/chat/providers/chat_providers.dart

@@ -406,7 +406,7 @@ Future<void> regenerateMessage(
       role: 'assistant',
       content: '',
       timestamp: DateTime.now(),
-      model: selectedModel.name,
+      model: selectedModel.id,
       isStreaming: true,
     );
     ref.read(chatMessagesProvider.notifier).addMessage(assistantMessage);
@@ -477,7 +477,7 @@ Future<void> regenerateMessage(
       role: 'assistant',
       content: '',
       timestamp: DateTime.now(),
-      model: selectedModel.name,
+      model: selectedModel.id,
       isStreaming: true,
     );
     ref.read(chatMessagesProvider.notifier).addMessage(assistantMessage);
@@ -547,6 +547,7 @@ Future<void> _sendMessageInternal(
     role: 'user',
     content: message,
     timestamp: DateTime.now(),
+    model: selectedModel.id,
     attachmentIds: attachments,
   );
 
@@ -649,7 +650,7 @@ Future<void> _sendMessageInternal(
       role: 'assistant',
       content: '',
       timestamp: DateTime.now(),
-      model: selectedModel.name,
+      model: selectedModel.id,
       isStreaming: true,
     );
     ref.read(chatMessagesProvider.notifier).addMessage(assistantMessage);
@@ -883,7 +884,7 @@ Future<void> _sendMessageInternal(
         role: 'assistant',
         content: '',
         timestamp: DateTime.now(),
-        model: selectedModel.name,
+        model: selectedModel.id,
         isStreaming: true,
       );
       ref.read(chatMessagesProvider.notifier).addMessage(imageOnlyAssistant);
@@ -1063,7 +1064,7 @@ Future<void> _sendMessageInternal(
       role: 'assistant',
       content: '',
       timestamp: DateTime.now(),
-      model: selectedModel.name,
+      model: selectedModel.id,
       isStreaming: true,
     );
     ref.read(chatMessagesProvider.notifier).addMessage(assistantMessage);
@@ -2378,7 +2379,7 @@ final regenerateLastMessageProvider = Provider<Future<void> Function()>((ref) {
         role: 'assistant',
         content: '',
         timestamp: DateTime.now(),
-        model: selectedModel.name,
+        model: selectedModel.id,
         isStreaming: true,
       );
       ref.read(chatMessagesProvider.notifier).addMessage(placeholder);

lib/features/chat/views/chat_page.dart

@@ -688,6 +688,29 @@ class _ChatPageState extends ConsumerState<ChatPage> {
 
         final isSelected = _selectedMessageIds.contains(message.id);
 
+        // Resolve a friendly model display name for message headers
+        String? displayModelName;
+        final rawModel = message.model;
+        if (rawModel != null && rawModel.isNotEmpty) {
+          final modelsAsync = ref.watch(modelsProvider);
+          if (modelsAsync.hasValue) {
+            final models = modelsAsync.value!;
+            try {
+              // Prefer exact ID match; fall back to exact name match
+              final match = models.firstWhere(
+                (m) => m.id == rawModel || m.name == rawModel,
+              );
+              displayModelName = match.name;
+            } catch (_) {
+              // As a fallback, format the raw value to be more readable
+              displayModelName = _formatModelDisplayName(rawModel);
+            }
+          } else {
+            // Models not loaded yet; format raw value for readability
+            displayModelName = _formatModelDisplayName(rawModel);
+          }
+        }
+
         // Wrap message in selection container if in selection mode
         Widget messageWidget;
 
@@ -698,7 +721,7 @@ class _ChatPageState extends ConsumerState<ChatPage> {
             message: message,
             isUser: isUser,
             isStreaming: isStreaming,
-            modelName: message.model,
+            modelName: displayModelName,
             onCopy: () => _copyMessage(message.content),
             onEdit: () => _editMessage(message),
             onRegenerate: () => _regenerateMessage(message),
@@ -710,7 +733,7 @@ class _ChatPageState extends ConsumerState<ChatPage> {
             key: ValueKey('assistant-${message.id}'),
             message: message,
             isStreaming: isStreaming,
-            modelName: message.model,
+            modelName: displayModelName,
             onCopy: () => _copyMessage(message.content),
             onRegenerate: () => _regenerateMessage(message),
             onLike: () => _likeMessage(message),