feat(chat): regenerate variants and support

Hide archived assistant variants in the linear chat view and track previous assistant as versions so regenerated responses do not duplicate or lose history. When regenerating, mark the previous assistant message with an archivedVariant flag for the UI and keep it in server history. Add a ChatMessageVersion model and a versions field to ChatMessage to store prior generated variants. Implement archiveLastAssistantAsVersion in chat providers to snapshot the last assistant message into versions and reset the message for a fresh streamed generation. Finalize flow updates to attach an adjacent archived assistant as a version when needed so the UI can present a switcher between current and past variants. These changes prevent duplicate messages, preserve previous responses, and enable variant switching.
2025-10-23 22:29:28 +05:30
parent 1a38cf02e5
commit 1cb8926e21
5 changed files with 326 additions and 29 deletions
--- a/lib/features/chat/providers/chat_providers.dart
+++ b/lib/features/chat/providers/chat_providers.dart
@@ -494,6 +494,45 @@ class ChatMessagesNotifier extends Notifier<List<ChatMessage>> {
    state = next;
  }

+  // Archive the last assistant message's current content as a previous version
+  // and clear it to prepare for regeneration, keeping the same message id.
+  void archiveLastAssistantAsVersion() {
+    if (state.isEmpty) return;
+    final last = state.last;
+    if (last.role != 'assistant') return;
+    // Do not archive if it's already streaming (nothing final to archive)
+    if (last.isStreaming) return;
+
+    final snapshot = ChatMessageVersion(
+      id: last.id,
+      content: last.content,
+      timestamp: last.timestamp,
+      model: last.model,
+      files: last.files == null
+          ? null
+          : List<Map<String, dynamic>>.from(last.files!),
+      sources: List<ChatSourceReference>.from(last.sources),
+      followUps: List<String>.from(last.followUps),
+      codeExecutions: List<ChatCodeExecution>.from(last.codeExecutions),
+      usage: last.usage == null ? null : Map<String, dynamic>.from(last.usage!),
+    );
+
+    final updated = last.copyWith(
+      // Start a fresh stream for the new generation
+      isStreaming: true,
+      content: '',
+      files: null,
+      followUps: const [],
+      codeExecutions: const [],
+      sources: const [],
+      usage: null,
+      versions: [...last.versions, snapshot],
+    );
+
+    state = [...state.sublist(0, state.length - 1), updated];
+    _touchStreamingActivity();
+  }
+
  void appendStatusUpdate(String messageId, ChatStatusUpdate update) {
    final withTimestamp = update.occurredAt == null
        ? update.copyWith(occurredAt: DateTime.now())
@@ -644,10 +683,38 @@ class ChatMessagesNotifier extends Notifier<List<ChatMessage>> {
    final finalized = _finalizeFormatter(lastMessage.id, lastMessage.content);
    final cleaned = _stripStreamingPlaceholders(finalized);

-    state = [
-      ...state.sublist(0, state.length - 1),
-      lastMessage.copyWith(isStreaming: false, content: cleaned),
-    ];
+    var updatedLast = lastMessage.copyWith(
+      isStreaming: false,
+      content: cleaned,
+    );
+
+    // Fallback: if there is an immediately previous assistant message
+    // marked as an archived variant and we have no versions yet, attach it
+    // as a version so the UI shows a switcher.
+    if (state.length >= 2 && updatedLast.versions.isEmpty) {
+      final prev = state[state.length - 2];
+      final isArchivedAssistant =
+          prev.role == 'assistant' &&
+          (prev.metadata?['archivedVariant'] == true);
+      if (isArchivedAssistant) {
+        final snapshot = ChatMessageVersion(
+          id: prev.id,
+          content: prev.content,
+          timestamp: prev.timestamp,
+          model: prev.model,
+          files: prev.files,
+          sources: prev.sources,
+          followUps: prev.followUps,
+          codeExecutions: prev.codeExecutions,
+          usage: prev.usage,
+        );
+        updatedLast = updatedLast.copyWith(
+          versions: [...updatedLast.versions, snapshot],
+        );
+      }
+    }
+
+    state = [...state.sublist(0, state.length - 1), updatedLast];
    _messageStream = null;
    _stopRemoteTaskMonitor();

@@ -1014,8 +1081,9 @@ Future<Map<String, dynamic>> _buildMessagePayloadWithAttachments({
 Future<void> regenerateMessage(
  dynamic ref,
  String userMessageContent,
-  List<String>? attachments,
-) async {
+  List<String>? attachments, [
+  String? existingAssistantId,
+]) async {
  final reviewerMode = ref.read(reviewerModeProvider);
  final api = ref.read(apiServiceProvider);
  final selectedModel = ref.read(selectedModelProvider);
@@ -1135,13 +1203,42 @@ Future<void> regenerateMessage(
      }
    }

-    // Pre-seed assistant skeleton and persist chain
+    // Pre-seed assistant skeleton and persist chain; always use a new id so
+    // server history can branch like OpenWebUI.
    final String assistantMessageId = await _preseedAssistantAndPersist(
      ref,
+      existingAssistantId: null,
      modelId: selectedModel.id,
      systemPrompt: effectiveSystemPrompt,
    );

+    // Attach previous assistant as a version snapshot to the new assistant
+    try {
+      final msgs = ref.read(chatMessagesProvider);
+      if (msgs.length >= 2) {
+        final prev = msgs[msgs.length - 2];
+        final last = msgs.last;
+        if (prev.role == 'assistant' && last.id == assistantMessageId) {
+          final snapshot = ChatMessageVersion(
+            id: prev.id,
+            content: prev.content,
+            timestamp: prev.timestamp,
+            model: prev.model,
+            files: prev.files,
+            sources: prev.sources,
+            followUps: prev.followUps,
+            codeExecutions: prev.codeExecutions,
+            usage: prev.usage,
+          );
+          ref
+              .read(chatMessagesProvider.notifier)
+              .updateLastMessageWithFunction(
+                (m) => m.copyWith(versions: [...m.versions, snapshot]),
+              );
+        }
+      }
+    } catch (_) {}
+
    // Feature toggles
    final webSearchEnabled =
        ref.read(webSearchEnabledProvider) &&
@@ -2223,8 +2320,16 @@ final regenerateLastMessageProvider = Provider<Future<void> Function()>((ref) {

    if (lastUserMessage == null) return;

-    // Remove last assistant message
-    ref.read(chatMessagesProvider.notifier).removeLastMessage();
+    // Mark previous assistant as an archived variant so UI can hide it
+    final notifier = ref.read(chatMessagesProvider.notifier);
+    if (lastAssistantMessage != null) {
+      notifier.updateLastMessageWithFunction((m) {
+        final meta = Map<String, dynamic>.from(m.metadata ?? const {});
+        meta['archivedVariant'] = true;
+        // Keep content/files intact for server persistence
+        return m.copyWith(metadata: meta, isStreaming: false);
+      });
+    }

    // If previous assistant was image-only or had images, regenerate images instead of text
    if (lastAssistantHadImages) {
--- a/lib/features/chat/views/chat_page.dart
+++ b/lib/features/chat/views/chat_page.dart
@@ -902,6 +902,13 @@ class _ChatPageState extends ConsumerState<ChatPage> {
                }
              }

+              // Hide archived assistant variants in the linear view
+              final isArchivedVariant =
+                  !isUser && (message.metadata?['archivedVariant'] == true);
+              if (isArchivedVariant) {
+                return const SizedBox.shrink();
+              }
+
              final showFollowUps =
                  !isUser && !hasUserBubbleBelow && !hasAssistantBubbleBelow;

@@ -990,8 +997,14 @@ class _ChatPageState extends ConsumerState<ChatPage> {
        return;
      }

-      // Remove the assistant message we want to regenerate
-      ref.read(chatMessagesProvider.notifier).removeLastMessage();
+      // Mark previous assistant as archived for UI; keep it for server history
+      ref.read(chatMessagesProvider.notifier).updateLastMessageWithFunction((
+        m,
+      ) {
+        final meta = Map<String, dynamic>.from(m.metadata ?? const {});
+        meta['archivedVariant'] = true;
+        return m.copyWith(metadata: meta, isStreaming: false);
+      });

      // Regenerate response for the previous user message (without duplicating it)
      final userMessage = messages[messageIndex - 1];
--- a/lib/features/chat/widgets/assistant_message_widget.dart
+++ b/lib/features/chat/widgets/assistant_message_widget.dart
@@ -70,6 +70,8 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
  bool _allowTypingIndicator = false;
  Timer? _typingGateTimer;
  String _ttsPlainText = '';
+  // Active version index (-1 means current/live content)
+  int _activeVersionIndex = -1;
  // press state handled by shared ChatActionButton

  Future<void> _handleFollowUpTap(String suggestion) async {
@@ -140,7 +142,10 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
  }

  void _reparseSections() {
-    final raw0 = widget.message.content ?? '';
+    final raw0 = _activeVersionIndex >= 0
+        ? (widget.message.versions[_activeVersionIndex].content as String?) ??
+              ''
+        : widget.message.content ?? '';
    // Strip any leftover placeholders from content before parsing
    const ti = '[TYPING_INDICATOR]';
    const searchBanner = '🔍 Searching the web...';
@@ -633,6 +638,10 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
        widget.showFollowUps &&
        widget.message.followUps.isNotEmpty &&
        !widget.isStreaming;
+    final bool showingVersion = _activeVersionIndex >= 0;
+    final activeFiles = showingVersion
+        ? widget.message.versions[_activeVersionIndex].files
+        : widget.message.files;
    final hasSources = widget.message.sources.isNotEmpty;

    return Container(
@@ -657,8 +666,7 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    // Display attachments - prioritize files array over attachmentIds to avoid duplication
-                    if (widget.message.files != null &&
-                        widget.message.files!.isNotEmpty) ...[
+                    if (activeFiles != null && activeFiles.isNotEmpty) ...[
                      _buildFilesFromArray(),
                      const SizedBox(height: Spacing.md),
                    ] else if (widget.message.attachmentIds != null &&
@@ -729,6 +737,8 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
                        messageId: widget.message.id,
                      ),
                    ],
+
+                    // Version switcher moved inline with action buttons below
                  ],
                ),
              ),
@@ -896,11 +906,14 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
  }

  Widget _buildFilesFromArray() {
-    if (widget.message.files == null || widget.message.files!.isEmpty) {
+    final filesArray = _activeVersionIndex >= 0
+        ? widget.message.versions[_activeVersionIndex].files
+        : widget.message.files;
+    if (filesArray == null || filesArray.isEmpty) {
      return const SizedBox.shrink();
    }

-    final allFiles = widget.message.files!;
+    final allFiles = filesArray;

    // Separate images and non-image files
    final imageFiles = allFiles
@@ -1077,6 +1090,8 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
    );
  }

+  // Deprecated: old in-content version switcher replaced by inline controls with action buttons.
+
  Widget _buildActionButtons() {
    final l10n = AppLocalizations.of(context)!;
    final ttsState = ref.watch(textToSpeechControllerProvider);
@@ -1139,6 +1154,43 @@ class _AssistantMessageWidgetState extends ConsumerState<AssistantMessageWidget>
          label: l10n.copy,
          onTap: widget.onCopy,
        ),
+        if (widget.message.versions.isNotEmpty && !widget.isStreaming) ...[
+          // Inline version toggle: Prev [1/n] Next
+          ChatActionButton(
+            icon: Icons.chevron_left,
+            label: 'Prev',
+            onTap: () {
+              setState(() {
+                if (_activeVersionIndex < 0) {
+                  _activeVersionIndex = widget.message.versions.length - 1;
+                } else if (_activeVersionIndex > 0) {
+                  _activeVersionIndex -= 1;
+                }
+                _reparseSections();
+              });
+            },
+          ),
+          ConduitChip(
+            label:
+                '${_activeVersionIndex < 0 ? (widget.message.versions.length + 1) : (_activeVersionIndex + 1)}/${widget.message.versions.length + 1}',
+            isCompact: true,
+          ),
+          ChatActionButton(
+            icon: Icons.chevron_right,
+            label: 'Next',
+            onTap: () {
+              setState(() {
+                if (_activeVersionIndex < 0) return; // already live
+                if (_activeVersionIndex < widget.message.versions.length - 1) {
+                  _activeVersionIndex += 1;
+                } else {
+                  _activeVersionIndex = -1; // move to live
+                }
+                _reparseSections();
+              });
+            },
+          ),
+        ],
        if (isErrorMessage) ...[
          _buildActionButton(
            icon: Platform.isIOS