Merge pull request #2167 from nextcloud/feat/neon_talk/references

Author: provokateurin

packages/neon/neon_talk/lib/src/blocs/message_bloc.dart

@@ -0,0 +1,88 @@
+import 'dart:async';
+
+import 'package:built_collection/built_collection.dart';
+import 'package:logging/logging.dart';
+import 'package:meta/meta.dart';
+import 'package:neon_framework/blocs.dart';
+import 'package:nextcloud/core.dart' as core;
+import 'package:nextcloud/spreed.dart' as spreed;
+import 'package:rxdart/rxdart.dart';
+
+/// Bloc for handling the message state and interactions.
+@sealed
+abstract class TalkMessageBloc implements Bloc {
+  /// Creates a new Talk message bloc.
+  factory TalkMessageBloc({
+    required spreed.$ChatMessageInterface chatMessage,
+    required ReferencesBloc referencesBloc,
+    required bool isParent,
+  }) = _TalkMessageBloc;
+
+  /// References contained in the message.
+  BehaviorSubject<BuiltMap<String, Result<core.Reference>>> get references;
+}
+
+class _TalkMessageBloc extends Bloc implements TalkMessageBloc {
+  _TalkMessageBloc({
+    required this.chatMessage,
+    required this.referencesBloc,
+    required this.isParent,
+  }) {
+    if (!isParent) {
+      referenceRegexSubscription = referencesBloc.referenceRegex.listen((result) {
+        final referenceRegex = result.data;
+        if (referenceRegex == null) {
+          return;
+        }
+
+        final matches =
+            referenceRegex.allMatches(chatMessage.message).map((match) => match.group(0)!.trim()).toBuiltList();
+
+        references.add(
+          references.value.rebuild((b) {
+            for (final match in matches) {
+              b[match] ??= Result.loading();
+            }
+
+            b.removeWhere((key, value) => !matches.contains(key));
+          }),
+        );
+
+        if (matches.isNotEmpty) {
+          referencesBloc.loadReferences(matches);
+        }
+      });
+
+      referencesSubscription = referencesBloc.references.listen((result) {
+        references.add(
+          references.value.rebuild((b) {
+            for (final url in references.value.keys) {
+              b[url] = result[url] ?? Result.loading();
+            }
+
+            b.removeWhere((key, value) => !result.keys.contains(key));
+          }),
+        );
+      });
+    }
+  }
+
+  final spreed.$ChatMessageInterface chatMessage;
+  final ReferencesBloc referencesBloc;
+  final bool isParent;
+  StreamSubscription<Result<RegExp?>>? referenceRegexSubscription;
+  StreamSubscription<BuiltMap<String, Result<core.Reference>>>? referencesSubscription;
+
+  @override
+  Logger log = Logger('TalkMessageBloc');
+
+  @override
+  void dispose() {
+    unawaited(referenceRegexSubscription?.cancel());
+    unawaited(referencesSubscription?.cancel());
+    unawaited(references.close());
+  }
+
+  @override
+  final references = BehaviorSubject.seeded(BuiltMap());
+}