Support for loading history and marking read

lib/widgets/room_chat.dart

@@ -7,6 +7,7 @@ import "package:nexus/controllers/account_data_controller.dart";
 import "package:nexus/controllers/client_controller.dart";
 import "package:nexus/controllers/client_state_controller.dart";
 import "package:nexus/controllers/power_level_controller.dart";
+import "package:nexus/controllers/rooms_controller.dart";
 import "package:nexus/controllers/selected_room_controller.dart";
 import "package:nexus/controllers/room_chat_controller.dart";
 import "package:nexus/controllers/via_controller.dart";
@@ -45,13 +46,6 @@ class RoomChat extends HookConsumerWidget {
 
     final memberListOpened = useState<bool>(showMembersByDefault);
 
-    final listController = useRef(ListController());
-    final scrollController = useScrollController(
-      onAttach: (position) => position.addListener(() {
-        // TODO: Do things on scroll to top or bottom
-      }),
-    );
-
     final userId = ref.watch(ClientStateController.provider)?.userId;
     final roomId = ref.watch(
       SelectedRoomController.provider.select((value) => value?.metadata?.id),
@@ -78,6 +72,21 @@ class RoomChat extends HookConsumerWidget {
     final controllerProvider = RoomChatController.provider(roomId);
     final notifier = ref.watch(controllerProvider.notifier);
 
+    final client = ref.watch(ClientController.provider.notifier);
+
+    final listController = useRef(ListController());
+    final scrollController = useScrollController();
+    scrollController.addListener(() async {
+      if (!scrollController.position.atEdge) return;
+
+      if (scrollController.position.pixels == 0) {
+        final room = ref.watch(RoomsController.provider)[roomId];
+        if (room != null) client.markRead(room);
+      } else {
+        await notifier.loadOlder();
+      }
+    });
+
     final composerNode = useFocusNode(
       onKeyEvent: (_, event) {
         if (event is KeyDownEvent &&
@@ -269,9 +278,7 @@ class RoomChat extends HookConsumerWidget {
                     ),
                     TextButton(
                       onPressed: () {
-                        ref
+                        client.reportEvent(
-                            .watch(ClientController.provider.notifier)
-                            .reportEvent(
                           ReportRequest(
                             roomId: roomId,
                             eventId: event.eventId,