Read receipt support

Fixes #93

gomuks

@@ -1 +1 @@
-Subproject commit ba82b6e31c87c99766a8366a72a9f07d643b323f
+Subproject commit a65299d327e3a533e6c476b0450b09be91fbb827

lib/controllers/client.dart

@@ -8,6 +8,7 @@ import "package:fast_immutable_collections/fast_immutable_collections.dart";
 import "package:ffi/ffi.dart";
 import "package:flutter/cupertino.dart";
 import "package:intl/intl.dart";
+import "package:nexus/controllers/settings.dart";
 import "package:nexus/helpers/extensions/gomuks_buffer.dart";
 import "package:nexus/models/capabilities.dart";
 import "package:nexus/models/content/message.dart";
@@ -106,39 +107,50 @@ class ClientController extends AsyncNotifier<int> {
     return handle;
   }
 
+  /// Calls gomuks with [data] as JSON, returning its decoded response.
   Future<dynamic> callGomuksMethod(
     Map<String, dynamic> data,
-    FutureOr<GomuksResponse> Function(int handle, GomuksBorrowedBuffer data)
-    callback,
+    void Function(
+      int handle,
+      GomuksOwnedBuffer data,
+      Pointer<NativeFunction<Void Function(GomuksResponse)>> callback,
+    )
+    call,
   ) async {
-    final bufferPointer = data.toGomuksBufferPtr();
+    final handle = await future;
+    final buffer = data.toGomuksOwnedBuffer();
+
+    final completer = Completer<dynamic>();
+    late final NativeCallable<Void Function(GomuksResponse)> callable;
+    callable = .listener((GomuksResponse response) {
+      callable.close();
+      try {
+        final json = response.buf.toJsonAndFree();
+
+        if (response.command.cast<Utf8>().toDartString() == "error") {
+          throw GomuksException(json.toString());
+        }
+
+        completer.complete(json);
+      } catch (error, stackTrace) {
+        completer.completeError(error, stackTrace);
+      }
+    });
 
     try {
-      final handle = await future;
-
-      final response = await Isolate.run(
-        () => callback(handle, bufferPointer.ref),
-      );
-
-      final json = response.buf.toJsonAndFree();
-
-      if (response.command.cast<Utf8>().toDartString() == "error") {
-        throw GomuksException(json.toString());
-      }
-
-      return json;
-    } finally {
-      calloc
-        ..free(bufferPointer.ref.base)
-        ..free(bufferPointer);
+      call(handle, buffer, callable.nativeFunction);
+    } catch (_) {
+      // gomuks never got the call, so it won't respond or free the buffer
+      callable.close();
+      GomuksFreeBuffer(buffer);
+      rethrow;
     }
+
+    return completer.future;
   }
 
   Future<PushNotification?> handlePush(Map<String, dynamic> data) async {
-    final response = await callGomuksMethod(
-      data,
-      (handle, data) async => GomuksHandlePush(handle, data),
-    );
+    final response = await callGomuksMethod(data, GomuksHandlePushAsync);
 
     return response?["notification"] == null
         ? null
@@ -148,11 +160,12 @@ class ClientController extends AsyncNotifier<int> {
   Future<dynamic> _sendCommand(
     String command, [
     Map<String, dynamic> data = const {},
-  ]) => callGomuksMethod(data, (handle, data) {
+  ]) => callGomuksMethod(data, (handle, data, callback) {
     final commandPointer = command.toNativeUtf8().cast<Char>();
     try {
-      return GomuksSubmitCommand(handle, commandPointer, data);
+      GomuksSubmitCommandAsync(handle, commandPointer, data, callback);
     } finally {
+      // gomuks copies the command name before returning
       calloc.free(commandPointer);
     }
   });
@@ -332,9 +345,14 @@ class ClientController extends AsyncNotifier<int> {
 
     if (event == null) return;
 
+    // Private until settings have loaded, in case the user turned sending off
+    final sendPublic =
+        ref.read(SettingsController.provider).value?.readReceipts ==
+        .showAndSend;
+
     await _sendCommand("mark_read", {
       "room_id": room.metadata!.id,
-      "receipt_type": "m.read",
+      "receipt_type": sendPublic ? "m.read" : "m.read.private",
       "event_id": event.eventId,
     });
   }

lib/controllers/read_receipts.dart

@@ -0,0 +1,90 @@
+import "package:collection/collection.dart";
+import "package:fast_immutable_collections/fast_immutable_collections.dart";
+import "package:flutter_riverpod/flutter_riverpod.dart";
+import "package:nexus/controllers/client_state.dart";
+import "package:nexus/controllers/room_chat.dart";
+import "package:nexus/controllers/rooms.dart";
+import "package:nexus/controllers/settings.dart";
+import "package:nexus/helpers/extensions/is_shown_as_message.dart";
+import "package:nexus/models/read_receipt.dart";
+
+/// Other users' read receipts in a chat, by the event ID of the message to
+/// show them under: the nearest message at or before what they've read.
+class ReadReceiptsController(final ChatParams chat)
+    extends Notifier<IMap<String, IList<ReadReceipt>>> {
+  @override
+  IMap<String, IList<ReadReceipt>> build() {
+    final shouldShow = ref.watch(
+      SettingsController.provider.select(
+        (settings) => settings.value?.readReceipts != .neither,
+      ),
+    );
+    if (!shouldShow) return const .empty();
+
+    final userId = ref.watch(
+      ClientStateController.provider.select((state) => state?.userId),
+    );
+    // The chat's own timeline, so receipts follow what's actually shown
+    final timeline = ref.watch(
+      RoomChatController.provider(chat)
+          .select((roomChat) => roomChat.value?.timeline),
+    );
+    final room = ref.watch(
+      RoomsController.provider.select(
+        (rooms) => switch (rooms[chat.roomId]) {
+          final room? => (events: room.events, receipts: room.receipts),
+          null => null,
+        },
+      ),
+    );
+    if (userId == null || timeline == null || room == null) {
+      return const .empty();
+    }
+
+    final events = timeline.map((rowId) => room.events[rowId]).nonNulls;
+    final indexes = IMap.fromEntries(
+      events.indexed.map((entry) => MapEntry(entry.$2.eventId, entry.$1)),
+    );
+    final messages = events.indexed
+        .where((entry) => entry.$2.isShownAsMessage)
+        .toIList();
+    final messageIndexes = messages.map((entry) => entry.$1).toList();
+
+    return room.receipts.values.flattened
+        .where(
+          (receipt) =>
+              receipt.userId != userId &&
+              // Receipts in threads are for the thread, not the timeline
+              receipt.thread == "main",
+        )
+        .map(
+          (receipt) => switch (indexes[receipt.eventId]) {
+            final index? => (
+              receipt: receipt,
+              message: lowerBound(messageIndexes, index + 1) - 1,
+            ),
+            null => null,
+          },
+        )
+        .nonNulls
+        .where((entry) => entry.message >= 0)
+        .groupListsBy((entry) => messages[entry.message].$2.eventId)
+        .map(
+          (eventId, entries) => MapEntry(
+            eventId,
+            entries
+                .map((entry) => entry.receipt)
+                .sorted((a, b) => b.timestamp.compareTo(a.timestamp))
+                .toIList(),
+          ),
+        )
+        .toIMap();
+  }
+
+  static final provider = NotifierProvider.family
+      .autoDispose<
+        ReadReceiptsController,
+        IMap<String, IList<ReadReceipt>>,
+        ChatParams
+      >(ReadReceiptsController.new);
+}

lib/controllers/room_chat.dart

@@ -156,6 +156,7 @@ class RoomChatController(final ChatParams info)
                   valueMapper: (event) => event,
                 ),
                 hasMore: response.hasMore,
+                receipts: response.receipts,
                 timeline: IMap.fromIterable(
                   response.events,
                   keyMapper: (event) => event.timelineRowId,

lib/controllers/rooms.dart

@@ -2,6 +2,7 @@ import "package:collection/collection.dart";
 import "package:fast_immutable_collections/fast_immutable_collections.dart";
 import "package:flutter_riverpod/flutter_riverpod.dart";
 import "package:nexus/models/event.dart";
+import "package:nexus/models/read_receipt.dart";
 import "package:nexus/models/room.dart";
 
 class RoomsController extends Notifier<IMap<String, Room>> {
@@ -33,6 +34,26 @@ class RoomsController extends Notifier<IMap<String, Room>> {
     .new(),
   );
 
+  static IMap<String, IList<ReadReceipt>> mergeReceipts(
+    IMap<String, IList<ReadReceipt>> existing,
+    IMap<String, IList<ReadReceipt>> incoming,
+  ) => incoming.isEmpty
+      ? existing
+      : existing.values.flattened
+            .followedBy(incoming.values.flattened)
+            .groupListsBy((receipt) => (receipt.userId, receipt.thread))
+            .values
+            .map(
+              (receipts) => receipts.reduce(
+                (newest, receipt) => newest.timestamp.isAfter(receipt.timestamp)
+                    ? newest
+                    : receipt,
+              ),
+            )
+            .groupListsBy((receipt) => receipt.eventId)
+            .map((eventId, receipts) => MapEntry(eventId, receipts.toIList()))
+            .toIMap();
+
   /// Adds events to their rooms, without changing the rooms' timelines.
   void storeEvents(Iterable<Event> events) => update(
     .new(
@@ -96,15 +117,11 @@ class RoomsController extends Notifier<IMap<String, Room>> {
               timeline: incoming.reset
                   ? incoming.timeline
                   : existing.timeline.addAll(incoming.timeline),
-              receipts: incoming.receipts.entries.fold(
-                existing.receipts,
-                (receiptAcc, event) => receiptAcc.add(
-                  event.key,
-                  (receiptAcc[event.key] ?? .new()).addAll(event.value),
-                ),
-              ),
+              receipts: mergeReceipts(existing.receipts, incoming.receipts),
             ) ??
-            incoming,
+            incoming.copyWith(
+              receipts: mergeReceipts(const .empty(), incoming.receipts),
+            ),
       );
     });
 

lib/controllers/settings_sections.dart

@@ -19,8 +19,9 @@ import "package:nexus/controllers/unified_push_distributors.dart";
 import "package:nexus/helpers/extensions/distributor_name.dart";
 import "package:nexus/models/account_data.dart";
 import "package:nexus/models/room_order.dart";
+import "package:nexus/models/settings.dart";
 import "package:nexus/models/settings_category.dart";
-import "package:nexus/models/typing_indicators.dart";
+import "package:nexus/models/show_and_send.dart";
 import "package:nexus/main.dart";
 import "package:nexus/widgets/settings/dialog_list_tile.dart";
 import "package:nexus/widgets/reset_encryption_sheet.dart";
@@ -32,6 +33,30 @@ class SettingsSectionsController
   Future<IMap<String, IList<SettingsCategory>>> build() async {
     final settings = await ref.watch(SettingsController.provider.future);
 
+    /// A tile for a [ShowAndSend] setting, saving the settings from [update].
+    Widget showAndSendTile(
+      String title,
+      String description,
+      IconData icon, {
+      required ShowAndSend value,
+      required Settings Function(ShowAndSend value) update,
+    }) => DialogListTile<ShowAndSend>(
+      icon: Icon(icon),
+      title: title,
+      subtitle: Text(description),
+      value: value,
+      options: ShowAndSend.values,
+      getName: (option) => switch (option) {
+        .showAndSend => "Show and send",
+        .show => "Only show",
+        .neither => "Neither",
+      },
+      onChanged: (value) => ref
+          .read(SettingsController.provider.notifier)
+          .set(update(value))
+          .onError(showError),
+    );
+
     return .new({
       "General": .new([
         .new(
@@ -192,23 +217,25 @@ class SettingsSectionsController
               title: "Typing Indicators",
               description: "Show when others are typing, and let others see when you're typing.",
               icon: Icons.keyboard,
-              builder: (title, description, icon) =>
-                  DialogListTile<TypingIndicators>(
-                    icon: Icon(icon),
-                    title: title,
-                    subtitle: Text(description),
-                    value: settings.typingIndicators,
-                    options: TypingIndicators.values,
-                    getName: (option) => switch (option) {
-                      .showAndSend => "Show and send",
-                      .show => "Only show",
-                      .neither => "Neither",
-                    },
-                    onChanged: (value) => ref
-                        .read(SettingsController.provider.notifier)
-                        .set(settings.copyWith(typingIndicators: value))
-                        .onError(showError),
-                  ),
+              builder: (title, description, icon) => showAndSendTile(
+                title,
+                description,
+                icon,
+                value: settings.typingIndicators,
+                update: (value) => settings.copyWith(typingIndicators: value),
+              ),
+            ),
+            .new(
+              title: "Read Receipts",
+              description: "Show how far others have read, and let others see what you've read. When not sent, read receipts are still sent privately, so your other devices know what you've read.",
+              icon: Icons.done_all,
+              builder: (title, description, icon) => showAndSendTile(
+                title,
+                description,
+                icon,
+                value: settings.readReceipts,
+                update: (value) => settings.copyWith(readReceipts: value),
+              ),
             ),
           ]),
         ),

lib/helpers/extensions/gomuks_buffer.dart

@@ -19,19 +19,21 @@ extension GomuksOwnedBufferToX on GomuksOwnedBuffer {
 }
 
 extension JsonToGomuksBuffer on Map<String, dynamic> {
+  GomuksOwnedBuffer toGomuksOwnedBuffer() {
+    final bytes = utf8.encode(json.encode(this));
+    final buffer = GomuksAllocBuffer(bytes.length);
+    buffer.base.asTypedList(bytes.length).setAll(0, bytes);
+    return buffer;
+  }
+
   Pointer<GomuksBorrowedBuffer> toGomuksBufferPtr() {
-    final jsonString = json.encode(this);
-    final bytes = utf8.encode(jsonString);
+    final bytes = utf8.encode(json.encode(this));
 
     final dataPtr = calloc<Uint8>(bytes.length);
     dataPtr.asTypedList(bytes.length).setAll(0, bytes);
 
-    final ptr = calloc<GomuksBorrowedBuffer>();
-
-    ptr.ref
-      ..base = dataPtr
-      ..length = bytes.length;
-
-    return ptr;
+    return calloc<GomuksBorrowedBuffer>()
+      ..ref.base = dataPtr
+      ..ref.length = bytes.length;
   }
 }

lib/helpers/extensions/is_shown_as_message.dart

@@ -0,0 +1,15 @@
+import "package:nexus/models/content/encrypted.dart";
+import "package:nexus/models/content/message.dart";
+import "package:nexus/models/content/sticker.dart";
+import "package:nexus/models/event.dart";
+
+extension IsShownAsMessage on Event {
+  /// Whether this is shown in the timeline as a message, with MessageRenderer.
+  bool get isShownAsMessage =>
+      redactedBy == null &&
+      relationType != "m.replace" &&
+      switch (content) {
+        MessageContent() || EncryptedContent() || StickerContent() => true,
+        _ => false,
+      };
+}

lib/models/paginate.dart

@@ -1,6 +1,7 @@
 import "package:fast_immutable_collections/fast_immutable_collections.dart";
 import "package:freezed_annotation/freezed_annotation.dart";
 import "package:nexus/models/event.dart";
+import "package:nexus/models/read_receipt.dart";
 
 part "paginate.freezed.dart";
 part "paginate.g.dart";
@@ -10,6 +11,9 @@ part "paginate.g.dart";
 class const Paginate({
   required final IList<Event> events,
   required final IList<Event> relatedEvents,
+
+  /// Read receipts for the events, by event ID.
+  final IMap<String, IList<ReadReceipt>> receipts = const .empty(),
   required final bool hasMore,
 }) with _$Paginate {
   Map<String, Object?> toJson() => _$PaginateToJson(this);

lib/models/read_receipt.dart

@@ -13,6 +13,11 @@ class const ReadReceipt({
   required final String eventId,
   @EpochDateTimeConverter() required final DateTime timestamp,
 }) with _$ReadReceipt {
+  String get thread => switch (threadId) {
+    final threadId? when threadId.isNotEmpty => threadId,
+    _ => "main",
+  };
+
   Map<String, Object?> toJson() => _$ReadReceiptToJson(this);
 
   factory ReadReceipt.fromJson(Map<String, Object?> json) =>

lib/models/settings.dart

@@ -1,7 +1,7 @@
 import "package:material_ui/material_ui.dart";
 import "package:freezed_annotation/freezed_annotation.dart";
 import "package:nexus/models/room_order.dart";
-import "package:nexus/models/typing_indicators.dart";
+import "package:nexus/models/show_and_send.dart";
 
 part "settings.freezed.dart";
 part "settings.g.dart";
@@ -17,7 +17,11 @@ class const Settings({
   final bool swipeToReply = false,
   final bool hideMembershipEvents = false,
   final RoomOrder roomOrder = .unreadFirst,
-  final TypingIndicators typingIndicators = .showAndSend,
+  final ShowAndSend typingIndicators = .showAndSend,
+
+  /// When not sending, read receipts are still sent privately, so that the
+  /// user's other devices know what has been read.
+  final ShowAndSend readReceipts = .showAndSend,
 }) with _$Settings {
   Map<String, Object?> toJson() => _$SettingsToJson(this);
 

lib/models/show_and_send.dart

@@ -0,0 +1,2 @@
+/// Whether to show something from others, and send it to them, e.g. typing indicators or read receipts.
+enum ShowAndSend { showAndSend, show, neither }

lib/models/typing_indicators.dart

@@ -1 +0,0 @@
-enum TypingIndicators { showAndSend, show, neither }

lib/widgets/avatar_ring.dart

@@ -0,0 +1,39 @@
+import "package:material_ui/material_ui.dart";
+
+class const AvatarRing({
+  required final String tooltip,
+  required final VoidCallback onTap,
+  required final Widget child,
+  final double dimension = 24,
+  super.key,
+}) extends StatelessWidget {
+  static const ringWidth = 1.5;
+
+  @override
+  Widget build(BuildContext context) => Tooltip(
+    message: tooltip,
+    child: Container(
+      padding: .all(ringWidth),
+      decoration: BoxDecoration(
+        color: Theme.of(context).colorScheme.surface,
+        shape: .circle,
+      ),
+      child: ClipOval(
+        child: SizedBox.square(
+          dimension: dimension,
+          child: Stack(
+            fit: .expand,
+            children: [
+              child,
+              // Over the child, so the ripple shows on top of avatars
+              Material(
+                type: .transparency,
+                child: InkWell(onTap: onTap),
+              ),
+            ],
+          ),
+        ),
+      ),
+    ),
+  );
+}

lib/widgets/read_receipts_row.dart

@@ -0,0 +1,112 @@
+import "package:hooks_riverpod/hooks_riverpod.dart";
+import "package:material_ui/material_ui.dart";
+import "package:nexus/controllers/read_receipts.dart";
+import "package:nexus/controllers/room_chat.dart";
+import "package:nexus/controllers/user.dart";
+import "package:nexus/helpers/extensions/get_localpart.dart";
+import "package:nexus/helpers/extensions/show_adaptive_sheet.dart";
+import "package:nexus/helpers/extensions/show_user_popover.dart";
+import "package:nexus/widgets/avatar_or_hash.dart";
+import "package:nexus/widgets/avatar_ring.dart";
+import "package:nexus/widgets/read_receipts_sheet.dart";
+
+class const ReadReceiptsRow(
+  final String eventId, {
+  required final ChatParams chat,
+  super.key,
+}) extends ConsumerWidget {
+  static const avatarSize = 24.0;
+  static const overlap = 6.0;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final theme = Theme.of(context);
+    final receipts = ref.watch(
+      ReadReceiptsController.provider(chat)
+          .select((receipts) => receipts[eventId] ?? const .empty()),
+    );
+
+    return AnimatedSize(
+      duration: Durations.medium2,
+      curve: Curves.easeInOutCubicEmphasized,
+      alignment: .topRight,
+      child: receipts.isEmpty
+          ? const SizedBox(width: .infinity)
+          : Padding(
+              // Clear of the scrollbar
+              padding: .only(right: 16, bottom: 2),
+              child: LayoutBuilder(
+                builder: (context, constraints) {
+                  const width = avatarSize + AvatarRing.ringWidth * 2;
+                  final fits =
+                      (constraints.maxWidth - width) ~/ (width - overlap) + 1;
+
+                  // If they don't all fit, the last spot shows how many more there are
+                  final shown = receipts.length <= fits
+                      ? receipts.length
+                      : fits - 1;
+
+                  return Align(
+                    alignment: .centerRight,
+                    child: Wrap(
+                      spacing: -overlap,
+                      children: [
+                        ...receipts
+                            .take(shown)
+                            .map(
+                              (receipt) => Consumer(
+                                builder: (context, ref, _) {
+                                  final member = ref
+                                      .watch(
+                                        UserController.provider(
+                                          .new(
+                                            roomId: chat.roomId,
+                                            userId: receipt.userId,
+                                          ),
+                                        ),
+                                      )
+                                      .value;
+                                  final name =
+                                      member?.displayName ??
+                                      receipt.userId.localpart;
+
+                                  return AvatarRing(
+                                    tooltip: name,
+                                    onTap: () => context.showUserPopover(
+                                      receipt.userId,
+                                      roomId: chat.roomId,
+                                    ),
+                                    child: AvatarOrHash(
+                                      member?.avatarUrl,
+                                      name,
+                                      dimension: avatarSize,
+                                    ),
+                                  );
+                                },
+                              ),
+                            ),
+                        if (receipts.length > shown)
+                          AvatarRing(
+                            tooltip: "Show everyone who has read up to here",
+                            onTap: () => context.showAdaptiveSheet(
+                              (_) => ReadReceiptsSheet(eventId, chat: chat),
+                            ),
+                            child: ColoredBox(
+                              color: theme.colorScheme.surfaceContainerHighest,
+                              child: Center(
+                                child: Text(
+                                  "+${receipts.length - shown}",
+                                  style: theme.textTheme.labelSmall,
+                                ),
+                              ),
+                            ),
+                          ),
+                      ],
+                    ),
+                  );
+                },
+              ),
+            ),
+    );
+  }
+}

lib/widgets/read_receipts_sheet.dart

@@ -0,0 +1,55 @@
+import "package:hooks_riverpod/hooks_riverpod.dart";
+import "package:material_ui/material_ui.dart";
+import "package:nexus/controllers/read_receipts.dart";
+import "package:nexus/controllers/room_chat.dart";
+import "package:nexus/controllers/user.dart";
+import "package:nexus/helpers/extensions/get_localpart.dart";
+import "package:nexus/helpers/extensions/show_user_popover.dart";
+import "package:nexus/widgets/avatar_or_hash.dart";
+import "package:nexus/widgets/sheet_layout.dart";
+
+/// Everyone who has read up to an event, kept up to date while open.
+class const ReadReceiptsSheet(
+  final String eventId, {
+  required final ChatParams chat,
+  super.key,
+}) extends ConsumerWidget {
+  @override
+  Widget build(BuildContext context, WidgetRef ref) => SheetLayout(
+    title: Text("Read by"),
+    actions: [
+      TextButton(onPressed: Navigator.of(context).pop, child: Text("Close")),
+    ],
+    children: ref
+        .watch(
+          ReadReceiptsController.provider(chat)
+              .select((receipts) => receipts[eventId] ?? const .empty()),
+        )
+        .map(
+          (receipt) => Consumer(
+            builder: (context, ref, _) {
+              final member = ref
+                  .watch(
+                    UserController.provider(
+                      .new(roomId: chat.roomId, userId: receipt.userId),
+                    ),
+                  )
+                  .value;
+              final name = member?.displayName ?? receipt.userId.localpart;
+
+              return ListTile(
+                contentPadding: .zero,
+                leading: AvatarOrHash(member?.avatarUrl, name, dimension: 40),
+                title: Text(name, overflow: .ellipsis),
+                subtitle: Text(receipt.userId, overflow: .ellipsis),
+                onTap: () => context.showUserPopover(
+                  receipt.userId,
+                  roomId: chat.roomId,
+                ),
+              );
+            },
+          ),
+        )
+        .toList(),
+  );
+}

lib/widgets/renderers/event.dart

@@ -7,27 +7,26 @@ import "package:nexus/controllers/event.dart";
 import "package:nexus/controllers/room_chat.dart";
 import "package:nexus/controllers/rooms.dart";
 import "package:nexus/controllers/settings.dart";
+import "package:nexus/helpers/extensions/is_shown_as_message.dart";
 import "package:nexus/helpers/extensions/show_adaptive_menu.dart";
 import "package:nexus/helpers/hooks/chat_scroll.dart";
 import "package:nexus/models/content/avatar.dart";
 import "package:nexus/models/content/canonical_alias.dart";
 import "package:nexus/models/content/content.dart";
 import "package:nexus/models/content/create.dart";
-import "package:nexus/models/content/encrypted.dart";
 import "package:nexus/models/content/history_visibility.dart";
 import "package:nexus/models/content/join_rules.dart";
 import "package:nexus/models/content/membership.dart";
-import "package:nexus/models/content/message.dart";
 import "package:nexus/models/content/pinned_events.dart";
 import "package:nexus/models/content/power_levels.dart";
 import "package:nexus/models/content/server_acl.dart";
-import "package:nexus/models/content/sticker.dart";
 import "package:nexus/models/content/topic.dart";
 import "package:nexus/models/event.dart";
 import "package:nexus/widgets/error_dialog.dart";
 import "package:nexus/widgets/lazy_loading/message_displayname.dart";
 import "package:nexus/widgets/renderers/message.dart";
 import "package:nexus/widgets/reaction_row.dart";
+import "package:nexus/widgets/read_receipts_row.dart";
 import "package:nexus/widgets/renderers/membership.dart";
 import "package:nexus/widgets/renderers/generic_event.dart";
 import "package:nexus/widgets/swipe_to_reply.dart";
@@ -44,6 +43,10 @@ class const EventRenderer(
 
   /// If set, events can be swiped, calling this
   final VoidCallback? onSwipe,
+
+  /// If set, shows who in this chat has read up to this event, e.g. in the
+  /// timeline.
+  final ChatParams? readReceiptsChat,
   super.key,
 }) extends HookConsumerWidget {
   @override
@@ -96,9 +99,7 @@ class const EventRenderer(
     }
 
     final isGrouped =
-        previousEvent?.content is MessageContent &&
-        previousEvent?.redactedBy == null &&
-        previousEvent?.relationType != "m.replace" &&
+        (previousEvent?.isShownAsMessage ?? false) &&
         event.sender == previousEvent?.sender &&
         event.pmp?.id == previousEvent?.pmp?.id;
 
@@ -111,7 +112,26 @@ class const EventRenderer(
           TextSpan(text: text),
         ]);
 
-    final child = event.redactedBy != null || event.relationType == "m.replace"
+    final child = event.isShownAsMessage
+        ? MessageRenderer(
+            event,
+            onTapReply: jumpToEvent == null
+                ? null
+                : () async {
+                    final replyEvent = await ref.read(
+                      EventController.provider(
+                        .new(roomId: roomId, eventId: event.replyTo!),
+                      ).future,
+                    );
+                    if (replyEvent != null) {
+                      await jumpToEvent!(replyEvent.rowId);
+                    }
+                  },
+            isGrouped: isGrouped,
+            maxLines: maxLines,
+            textOnly: textOnly,
+          )
+        : event.redactedBy != null || event.relationType == "m.replace"
         ? null
         : switch (event.content) {
             Content(:final parseError?, :final stackTrace) => Row(
@@ -123,27 +143,6 @@ class const EventRenderer(
               ],
             ),
 
-            MessageContent() ||
-            EncryptedContent() ||
-            StickerContent() => MessageRenderer(
-              event,
-              onTapReply: jumpToEvent == null
-                  ? null
-                  : () async {
-                      final replyEvent = await ref.read(
-                        EventController.provider(
-                          .new(roomId: roomId, eventId: event.replyTo!),
-                        ).future,
-                      );
-                      if (replyEvent != null) {
-                        await jumpToEvent!(replyEvent.rowId);
-                      }
-                    },
-              isGrouped: isGrouped,
-              maxLines: maxLines,
-              textOnly: textOnly,
-            ),
-
             MembershipContent content => switch (event.previousContent) {
               MembershipContent(:final status) =>
                 status == content.status
@@ -285,6 +284,10 @@ class const EventRenderer(
             ...[
               if (child is! MessageRenderer) ReactionRow(event),
 
+              // Outside the message itself, so it doesn't move when swiped
+              if (readReceiptsChat case final chat? when event.isShownAsMessage)
+                ReadReceiptsRow(event.eventId, chat: chat),
+
               if (event.sendError != null && event.sendError != "not sent")
                 Padding(
                   padding: .only(bottom: 4),

lib/widgets/room_chat/chat_timeline.dart

@@ -1,5 +1,6 @@
 import "package:fast_immutable_collections/fast_immutable_collections.dart";
 import "package:material_ui/material_ui.dart";
+import "package:nexus/controllers/room_chat.dart";
 import "package:nexus/helpers/hooks/chat_scroll.dart";
 import "package:nexus/models/event.dart";
 import "package:nexus/widgets/renderers/event.dart";
@@ -7,7 +8,7 @@ import "package:nexus/widgets/highlight_wrapper.dart";
 import "package:super_sliver_list/super_sliver_list.dart";
 
 class const ChatTimeline({
-  required final String roomId,
+  required final ChatParams chat,
   required final ChatScroll scroll,
   required final JumpToEvent jumpToEvent,
   required final IList<PopupMenuEntry> Function(Event) getEventOptions,
@@ -27,10 +28,11 @@ class const ChatTimeline({
     EventRenderer(
       eventRowId,
       previousEventRowId: previousEventRowId,
-      roomId: roomId,
+      roomId: chat.roomId,
       jumpToEvent: jumpToEvent,
       getEventOptions: getEventOptions,
       onSwipe: onSwipe == null ? null : () => onSwipe!(eventRowId),
+      readReceiptsChat: chat,
     ),
     key: key,
     isHighlighted: highlightedEvent == eventRowId,

lib/widgets/room_chat/room_chat.dart

@@ -85,10 +85,11 @@ final class const RoomChat({
       ),
     );
 
-    final controllerProvider = RoomChatController.provider((
+    final ChatParams chat = (
       roomId: roomId,
       contextualEvent: contextualEvent.value,
-    ));
+    );
+    final controllerProvider = RoomChatController.provider(chat);
     final notifier = ref.watch(controllerProvider.notifier);
 
     final client = ref.read(ClientController.provider.notifier);
@@ -246,7 +247,7 @@ final class const RoomChat({
                                     AsyncLoading(value: _?) ||
                                     AsyncData(value: _) => ChatTimeline(
                                       scroll: scroll,
-                                      roomId: roomId,
+                                      chat: chat,
                                       jumpToEvent: jumpToEvent,
                                       getEventOptions: getEventOptions,
                                       onSwipe: swipeToReply && canReply