chat search now lists local and server-side hits like the file search, and jumping to old messages pages in history with a progress banner and keeps the hit marked

lib/view/pages/talk/search/chat_search_controller.dart

@@ -0,0 +1,129 @@
+import 'package:flutter/foundation.dart';
+
+import '../../../../api/demo/demo_mode.dart';
+import '../../../../api/marianumcloud/search/search_chat_messages.dart';
+import '../../../../api/marianumcloud/talk/chat/get_chat_response.dart';
+import '../../../../utils/debouncer.dart';
+import '../data/chat_message_matcher.dart';
+
+/// Live state of a search inside one chat, mirroring `FilesSearchController`:
+/// hits from the loaded history appear immediately, the server-side search
+/// over the full history follows debounced and can be paged further.
+class ChatSearchController extends ChangeNotifier {
+  ChatSearchController({
+    required this.chatToken,
+    required GetChatResponse? Function() loadedMessages,
+  }) : _loadedMessages = loadedMessages;
+
+  final String chatToken;
+  final GetChatResponse? Function() _loadedMessages;
+
+  static const Duration _serverDebounce = Duration(seconds: 1);
+  final String _debounceTag =
+      'chat-search-${DateTime.now().microsecondsSinceEpoch}';
+  final SearchChatMessages _api = SearchChatMessages();
+
+  String _query = '';
+  List<ChatSearchHit> _localResults = const [];
+  List<ChatSearchHit> _serverResults = const [];
+  Object? _serverCursor;
+  bool _serverLoading = false;
+  bool _loadingMore = false;
+  Object? _serverError;
+  int _serverEpoch = 0;
+  bool _disposed = false;
+
+  void _safeNotify() {
+    if (_disposed) return;
+    notifyListeners();
+  }
+
+  String get query => _query;
+  bool get serverLoading => _serverLoading;
+  bool get loadingMore => _loadingMore;
+  bool get canLoadMore => _serverCursor != null;
+  Object? get serverError => _serverError;
+
+  List<ChatSearchHit> get combinedResults =>
+      ChatMessageMatcher.merge(_localResults, _serverResults);
+
+  void setQuery(String value) {
+    if (value == _query) return;
+    _query = value;
+    // Invalidates in-flight server calls of the previous query.
+    ++_serverEpoch;
+    _serverResults = const [];
+    _serverCursor = null;
+    _loadingMore = false;
+    _serverError = null;
+    if (_query.trim().isEmpty) {
+      Debouncer.cancel(_debounceTag);
+      _localResults = const [];
+      _serverLoading = false;
+      _safeNotify();
+      return;
+    }
+    final loaded = _loadedMessages();
+    _localResults = loaded == null
+        ? const []
+        : ChatMessageMatcher.findMatches(loaded, _query);
+    // Demo sessions must not hit the real Nextcloud (see DemoHttpClient).
+    _serverLoading = !DemoMode.active;
+    _safeNotify();
+    if (_serverLoading) {
+      Debouncer.debounce(_debounceTag, _serverDebounce, _runServerCall);
+    }
+  }
+
+  void retry() {
+    if (_query.trim().isEmpty || DemoMode.active) return;
+    ++_serverEpoch;
+    Debouncer.cancel(_debounceTag);
+    _serverResults = const [];
+    _serverCursor = null;
+    _loadingMore = false;
+    _serverLoading = true;
+    _serverError = null;
+    _safeNotify();
+    _runServerCall();
+  }
+
+  void loadMore() {
+    if (_serverCursor == null || _serverLoading || _loadingMore) return;
+    _loadingMore = true;
+    _safeNotify();
+    _runServerCall(cursor: _serverCursor);
+  }
+
+  Future<void> _runServerCall({Object? cursor}) async {
+    final epoch = _serverEpoch;
+    try {
+      final response = await _api.run(
+        chatToken: chatToken,
+        term: _query.trim(),
+        cursor: cursor,
+      );
+      if (epoch != _serverEpoch) return;
+      _serverResults = [
+        ..._serverResults,
+        ...response.entries.map(ChatSearchHit.fromServer),
+      ];
+      _serverCursor = response.cursor;
+      _serverError = null;
+    } on Object catch (e) {
+      if (epoch != _serverEpoch) return;
+      _serverCursor = null;
+      _serverError = e;
+    }
+    _serverLoading = false;
+    _loadingMore = false;
+    _safeNotify();
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    Debouncer.cancel(_debounceTag);
+    super.dispose();
+  }
+}