fix(schedule): load scheduled messages from the server; offer to cancel them at logout (#322)

The tray only knew what this browser had scheduled (localStorage), but
Synapse lists every pending one via MSC4140 GET /delayed_events. Load it
when the tray mounts and on window focus (localStorage stays as a first-
paint cache), keeping only non-state m.room.message events. Logout now
says "N scheduled messages still send after you log out" and offers to
cancel them.

Fixes #322

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/components/AccountDataEditor.tsx

@@ -297,7 +297,7 @@ export function AccountDataEditor({
             </Chip>
           </Box>
           <Box shrink="No">
-            <IconButton type="button" onClick={requestClose} variant="Surface" aria-label="Close">
+            <IconButton onClick={requestClose} variant="Surface" aria-label="Close">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>

src/app/components/CallEmbedProvider.tsx

@@ -111,8 +111,6 @@ type IncomingCallInfo = {
   intent?: string;
   notificationType: RTCNotificationType;
   refEventId: string;
-  /** [Gitea #313] The rtc.notification event itself: what a decline must reference (MSC4310). */
-  notificationEventId?: string;
 };
 type IncomingCallProps = {
   dm: boolean;
@@ -285,9 +283,7 @@ function IncomingCall({ dm, info, onIgnore, onAnswer, onReject }: IncomingCallPr
                   fill="Soft"
                   size="400"
                   radii="400"
-                  onClick={() =>
-                    dm ? onReject(room, info.notificationEventId ?? info.refEventId) : onIgnore()
-                  }
+                  onClick={() => (dm ? onReject(room, info.refEventId) : onIgnore())}
                   before={<Icon size="200" src={Icons.Cross} filled />}
                 >
                   <Text as="span" size="B400">
@@ -459,9 +455,7 @@ function IncomingCallBanner({ dm, info, onIgnore, onAnswer, onReject }: Incoming
           size="300"
           radii="300"
           outlined
-          onClick={() =>
-            dm ? onReject(room, info.notificationEventId ?? info.refEventId) : onIgnore()
-          }
+          onClick={() => (dm ? onReject(room, info.refEventId) : onIgnore())}
           before={<Icon size="100" src={Icons.Cross} filled />}
         >
           <Text as="span" size="B300">
@@ -602,7 +596,6 @@ function IncomingCallListener({ callEmbed, joined }: IncomingCallListenerProps)
             : undefined,
         notificationType,
         refEventId,
-        notificationEventId: event.getId(),
       };
 
       // [Gitea #312] Don't ring for a call that is already over or handled: after
@@ -611,10 +604,7 @@ function IncomingCallListener({ callEmbed, joined }: IncomingCallListenerProps)
       // stale RTC session). The caller's membership can arrive just after the
       // ring, so an absent one gets a short grace period before giving up.
       const myUserId = mx.getSafeUserId();
-      if (
-        declinedRing(room, [refEventId, event.getId()], myUserId) ||
-        hasActiveCallMembership(room, myUserId)
-      ) {
+      if (declinedRing(room, refEventId, myUserId) || hasActiveCallMembership(room, myUserId)) {
         return;
       }
       if (hasActiveCallMembership(room, sender)) {
@@ -623,10 +613,7 @@ function IncomingCallListener({ callEmbed, joined }: IncomingCallListenerProps)
       }
       setTimeout(() => {
         if (Date.now() >= senderTs + lifetime) return;
-        if (
-          declinedRing(room, [refEventId, event.getId()], myUserId) ||
-          hasActiveCallMembership(room, myUserId)
-        ) {
+        if (declinedRing(room, refEventId, myUserId) || hasActiveCallMembership(room, myUserId)) {
           return;
         }
         if (hasActiveCallMembership(room, sender)) setCallInfo(info);
@@ -698,10 +685,7 @@ function IncomingCallListener({ callEmbed, joined }: IncomingCallListenerProps)
       if (eventRoom?.roomId !== room.roomId || !data.liveEvent) return;
       if (event.getType() === EventType.RTCDecline && event.getSender() === myUserId) {
         const related = event.getRelation()?.event_id;
-        // [Gitea #313] Correct clients reference the notification; older Lotus
-        // builds referenced the call membership. Accept both.
-        if (!related || related === refEventId || related === callInfo.notificationEventId)
-          dismiss(); // declined elsewhere
+        if (!related || related === refEventId) dismiss(); // declined elsewhere
       }
     };
     session.on(MatrixRTCSessionEvent.MembershipsChanged, checkMemberships);

src/app/components/DeviceVerificationSetup.tsx

@@ -315,7 +315,7 @@ export const DeviceVerificationSetup = forwardRef<HTMLDivElement, DeviceVerifica
               Setup Device Verification
             </Text>
           </Box>
-          <IconButton type="button" size="300" radii="300" onClick={onCancel} aria-label="Cancel">
+          <IconButton size="300" radii="300" onClick={onCancel} aria-label="Cancel">
             <Icon src={Icons.Cross} />
           </IconButton>
         </Header>
@@ -361,7 +361,7 @@ export const DeviceVerificationReset = forwardRef<HTMLDivElement, DeviceVerifica
               Reset Device Verification
             </Text>
           </Box>
-          <IconButton type="button" size="300" radii="300" onClick={onCancel} aria-label="Cancel">
+          <IconButton size="300" radii="300" onClick={onCancel} aria-label="Cancel">
             <Icon src={Icons.Cross} />
           </IconButton>
         </Header>

src/app/components/LogoutDialog.tsx

@@ -1,4 +1,4 @@
-import React, { forwardRef, useCallback } from 'react';
+import React, { forwardRef, useCallback, useEffect, useState } from 'react';
 import { Dialog, Header, config, Box, Text, Button, Spinner, color } from 'folds';
 import { useAtom } from 'jotai';
 import { AsyncStatus, useAsyncCallback } from '../hooks/useAsyncCallback';
@@ -9,6 +9,8 @@ import { useMatrixClient } from '../hooks/useMatrixClient';
 import { useModalStyle } from '../hooks/useModalStyle';
 import { useCrossSigningActive } from '../hooks/useCrossSigning';
 import { InfoCard } from './info-card';
+import { ScheduledMessage } from '../state/scheduledMessages';
+import { cancelScheduledMessage, fetchScheduledMessages } from '../utils/scheduledMessages';
 import {
   useDeviceVerificationStatus,
   VerificationStatus,
@@ -36,17 +38,36 @@ export const LogoutDialog = forwardRef<HTMLDivElement, LogoutDialogProps>(
 
     const [callEmbed, setCallEmbed] = useAtom(callEmbedAtom);
 
-    const [logoutState, logout] = useAsyncCallback<void, Error, []>(
-      useCallback(async () => {
-        // [Gitea #29] Logging out mid-call must hang up first, or the MatrixRTC
-        // membership (expires: 4 h) stays behind as a ghost participant and
-        // everyone else sees you "in call" until it times out.
-        if (callEmbed && callEmbed.joined && !callEmbed.disposed) {
-          await hangupCallAndWait(mx, callEmbed);
-          setCallEmbed(undefined);
-        }
-        await logoutClient(mx);
-      }, [mx, callEmbed, setCallEmbed]),
+    // [Gitea #322] Scheduled messages live on the server and still send after
+    // logout, where no client would show them. Say so, and offer to cancel.
+    const [scheduled, setScheduled] = useState<ScheduledMessage[]>([]);
+    useEffect(() => {
+      let alive = true;
+      fetchScheduledMessages(mx)
+        .then((list) => alive && setScheduled(list))
+        .catch(() => undefined);
+      return () => {
+        alive = false;
+      };
+    }, [mx]);
+
+    const [logoutState, logout] = useAsyncCallback<void, Error, [boolean?]>(
+      useCallback(
+        async (cancelScheduled?: boolean) => {
+          if (cancelScheduled) {
+            await Promise.all(scheduled.map((m) => cancelScheduledMessage(mx, m.delayId)));
+          }
+          // [Gitea #29] Logging out mid-call must hang up first, or the MatrixRTC
+          // membership (expires: 4 h) stays behind as a ghost participant and
+          // everyone else sees you "in call" until it times out.
+          if (callEmbed && callEmbed.joined && !callEmbed.disposed) {
+            await hangupCallAndWait(mx, callEmbed);
+            setCallEmbed(undefined);
+          }
+          await logoutClient(mx);
+        },
+        [mx, callEmbed, setCallEmbed, scheduled],
+      ),
     );
 
     const ongoingLogout = logoutState.status === AsyncStatus.Loading;
@@ -93,6 +114,13 @@ export const LogoutDialog = forwardRef<HTMLDivElement, LogoutDialogProps>(
                 description="Enable device verification or export your encrypted data from settings to avoid losing access to your messages."
               />
             ))}
+          {scheduled.length > 0 && (
+            <InfoCard
+              variant="Warning"
+              title={`${scheduled.length} scheduled message${scheduled.length === 1 ? '' : 's'}`}
+              description="Scheduled messages still send after you log out. Cancel them now if you don't want them sent."
+            />
+          )}
           <Text priority="400">You’re about to log out. Are you sure?</Text>
           {logoutState.status === AsyncStatus.Error && (
             <Text style={{ color: color.Critical.Main }} size="T300">
@@ -102,12 +130,24 @@ export const LogoutDialog = forwardRef<HTMLDivElement, LogoutDialogProps>(
           <Box direction="Column" gap="200">
             <Button
               variant="Critical"
-              onClick={logout}
+              onClick={() => logout()}
               disabled={ongoingLogout}
               before={ongoingLogout && <Spinner variant="Critical" fill="Solid" size="200" />}
             >
-              <Text size="B400">Logout</Text>
+              <Text size="B400">
+                {scheduled.length > 0 ? 'Logout and keep scheduled messages' : 'Logout'}
+              </Text>
             </Button>
+            {scheduled.length > 0 && (
+              <Button
+                variant="Critical"
+                fill="Soft"
+                onClick={() => logout(true)}
+                disabled={ongoingLogout}
+              >
+                <Text size="B400">Cancel scheduled messages and logout</Text>
+              </Button>
+            )}
             <Button variant="Secondary" fill="Soft" onClick={handleClose} disabled={ongoingLogout}>
               <Text size="B400">Cancel</Text>
             </Button>

src/app/features/common-settings/developer-tools/StateEventEditor.tsx

@@ -275,7 +275,7 @@ export function StateEventEditor({ type, stateKey, requestClose }: StateEventEdi
             </Chip>
           </Box>
           <Box shrink="No">
-            <IconButton type="button" onClick={requestClose} variant="Surface" aria-label="Close">
+            <IconButton onClick={requestClose} variant="Surface" aria-label="Close">
               <Icon src={Icons.Cross} />
             </IconButton>
           </Box>

src/app/features/room/PollCreator.tsx

@@ -143,7 +143,7 @@ export function PollCreator({ roomId, threadRootId, onClose }: PollCreatorProps)
                   Create Poll
                 </Text>
               </Box>
-              <IconButton type="button" size="300" radii="300" onClick={onClose} aria-label="Close">
+              <IconButton size="300" radii="300" onClick={onClose} aria-label="Close">
                 <Icon src={Icons.Cross} />
               </IconButton>
             </Header>

src/app/features/room/ReportRoomModal.tsx

@@ -118,7 +118,7 @@ export function ReportRoomModal({ roomId, onClose }: ReportRoomModalProps) {
                   Report Room
                 </Text>
               </Box>
-              <IconButton type="button" size="300" onClick={onClose} radii="300" aria-label="Close">
+              <IconButton size="300" onClick={onClose} radii="300" aria-label="Close">
                 <Icon src={Icons.Cross} />
               </IconButton>
             </Header>

src/app/features/room/ReportUserModal.tsx

@@ -124,7 +124,7 @@ export function ReportUserModal({ userId, onClose }: ReportUserModalProps) {
                   Report User
                 </Text>
               </Box>
-              <IconButton type="button" size="300" onClick={onClose} radii="300" aria-label="Close">
+              <IconButton size="300" onClick={onClose} radii="300" aria-label="Close">
                 <Icon src={Icons.Cross} />
               </IconButton>
             </Header>

src/app/features/room/RoomTimeline.tsx

@@ -138,7 +138,7 @@ import { useMediaAuthentication } from '../../hooks/useMediaAuthentication';
 import { useIgnoredUsers } from '../../hooks/useIgnoredUsers';
 import { useImagePackRooms } from '../../hooks/useImagePackRooms';
 import { useIsDirectRoom } from '../../hooks/useRoom';
-import { declinedRing, isRingableRoom } from '../../utils/callRing';
+import { isRingableRoom } from '../../utils/callRing';
 import { useOpenUserRoomProfile } from '../../state/hooks/userRoomProfile';
 import { useSpaceOptionally } from '../../hooks/useSpace';
 import { useRoomCreators } from '../../hooks/useRoomCreators';
@@ -2037,9 +2037,6 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
         // Same rule as ringing: no "Missed call" in voice rooms or space
         // channels, where starting a call is just joining the channel.
         if (!isRingableRoom(room, direct)) return null;
-        // [Gitea #313] A call we declined isn't a missed call.
-        const ringRef = mEvent.getRelation()?.event_id;
-        if (declinedRing(room, [mEventId, ringRef], mx.getSafeUserId())) return null;
         const content = mEvent.getContent();
         const mention =
           content['m.mentions']?.room ||

src/app/features/room/ScheduleMessageModal.tsx

@@ -202,7 +202,7 @@ export function ScheduleMessageModal({
                   {title}
                 </Text>
               </Box>
-              <IconButton type="button" size="300" radii="300" onClick={onClose} aria-label="Close">
+              <IconButton size="300" radii="300" onClick={onClose} aria-label="Close">
                 <Icon src={Icons.Cross} />
               </IconButton>
             </Header>

src/app/features/room/ScheduledMessagesTray.tsx

@@ -4,7 +4,12 @@ import { IContent } from 'matrix-js-sdk';
 import { Box, Button, Icon, IconButton, Icons, Text, color, config } from 'folds';
 import { useMatrixClient } from '../../hooks/useMatrixClient';
 import { scheduledMessagesAtom, ScheduledMessage } from '../../state/scheduledMessages';
-import { cancelScheduledMessage, sendScheduledMessageNow } from '../../utils/scheduledMessages';
+import {
+  cancelScheduledMessage,
+  fetchScheduledMessages,
+  groupScheduledByRoom,
+  sendScheduledMessageNow,
+} from '../../utils/scheduledMessages';
 import { ScheduleMessageModal } from './ScheduleMessageModal';
 import { useTimestampFormatter } from '../../hooks/useTimestampFormatter';
 import { formatFriendlyDateTime } from '../../utils/datetimeInput';
@@ -26,6 +31,26 @@ export function ScheduledMessagesTray({ roomId }: ScheduledMessagesTrayProps) {
 
   const messages = useMemo(() => scheduledMessages.get(roomId) ?? [], [scheduledMessages, roomId]);
 
+  // [Gitea #322] The server is the source of truth: messages scheduled on
+  // another device (or before a logout) show up here and can be cancelled.
+  // localStorage is only a cache for the first paint; on error we keep it.
+  useEffect(() => {
+    let alive = true;
+    const load = () => {
+      fetchScheduledMessages(mx)
+        .then((list) => {
+          if (alive) setScheduledMessages(groupScheduledByRoom(list));
+        })
+        .catch(() => undefined);
+    };
+    load();
+    window.addEventListener('focus', load);
+    return () => {
+      alive = false;
+      window.removeEventListener('focus', load);
+    };
+  }, [mx, roomId, setScheduledMessages]);
+
   // Remove scheduled messages whose time has passed
   useEffect(() => {
     if (messages.length === 0) return undefined;

src/app/features/room/message/Message.tsx

@@ -725,13 +725,7 @@ export const MessageDeleteItem = as<
                     Delete Message
                   </Text>
                 </Box>
-                <IconButton
-                  type="button"
-                  size="300"
-                  onClick={handleClose}
-                  radii="300"
-                  aria-label="Close"
-                >
+                <IconButton size="300" onClick={handleClose} radii="300" aria-label="Close">
                   <Icon src={Icons.Cross} />
                 </IconButton>
               </Header>
@@ -871,13 +865,7 @@ export const MessageReportItem = as<
                     Report Message
                   </Text>
                 </Box>
-                <IconButton
-                  type="button"
-                  size="300"
-                  onClick={handleClose}
-                  radii="300"
-                  aria-label="Close"
-                >
+                <IconButton size="300" onClick={handleClose} radii="300" aria-label="Close">
                   <Icon src={Icons.Cross} />
                 </IconButton>
               </Header>

src/app/state/scheduledMessages.ts

@@ -21,8 +21,8 @@ const internalAtom = atomWithStorage<Record<string, ScheduledMessage[]>>(
 /**
  * Global atom: Map<roomId, ScheduledMessage[]>
  * Stores all locally-tracked scheduled messages across rooms.
- * MSC4140 has no list endpoint, so we track them ourselves.
- * Backed by localStorage so scheduled messages survive page refreshes.
+ * Loaded from the server's MSC4140 `GET /delayed_events` when the tray mounts
+ * (Gitea #322); localStorage is a cache for the first paint.
  */
 export const scheduledMessagesAtom = atom(
   (get): Map<string, ScheduledMessage[]> => new Map(Object.entries(get(internalAtom))),

src/app/utils/callRing.test.ts

@@ -67,18 +67,3 @@ test('declinedRing finds our own decline of that ring only (#312)', () => {
   assert.equal(declinedRing(room, '$ring2', '@me:x'), false, "someone else's decline");
   assert.equal(declinedRing(room, '$ring3', '@me:x'), false);
 });
-
-test('declinedRing matches a decline of the notification or of the membership (#313)', () => {
-  const decline = (rel: string) => ({
-    getType: () => 'org.matrix.msc4310.rtc.decline',
-    getSender: () => '@me:x',
-    getRelation: () => ({ event_id: rel }),
-  });
-  const room = stateRoom([], [decline('$notification')]);
-  assert.equal(declinedRing(room, ['$membership', '$notification'], '@me:x'), true);
-  assert.equal(declinedRing(room, ['$membership'], '@me:x'), false);
-  assert.equal(
-    declinedRing(stateRoom([], [decline('$membership')]), ['$membership', undefined], '@me:x'),
-    true,
-  );
-});

src/app/utils/callRing.ts

@@ -40,18 +40,7 @@ export const hasActiveCallMembership = (room: Room, userId: string): boolean =>
  * declined it (our own RTCDecline relates to it) — e.g. replayed together with
  * the ring in the first sync after a restart, before any dismiss listener.
  */
-export const declinedRing = (
-  room: Room,
-  ringIds: string | Array<string | undefined>,
-  myUserId: string,
-): boolean => {
-  // [Gitea #313] A decline references the notification event (MSC4310); older
-  // Lotus builds referenced the call membership instead. Match either.
-  const ids = new Set((Array.isArray(ringIds) ? ringIds : [ringIds]).filter(Boolean));
-  return declinedAny(room, ids, myUserId);
-};
-
-const declinedAny = (room: Room, ids: Set<string | undefined>, myUserId: string): boolean =>
+export const declinedRing = (room: Room, refEventId: string, myUserId: string): boolean =>
   room
     .getLiveTimeline()
     .getEvents()
@@ -59,5 +48,5 @@ const declinedAny = (room: Room, ids: Set<string | undefined>, myUserId: string)
       (ev) =>
         ev.getType() === 'org.matrix.msc4310.rtc.decline' &&
         ev.getSender() === myUserId &&
-        ids.has(ev.getRelation()?.event_id),
+        ev.getRelation()?.event_id === refEventId,
     );

src/app/utils/scheduledMessages.test.ts

@@ -6,6 +6,8 @@ import {
   scheduleMessage,
   cancelScheduledMessage,
   restartScheduledMessage,
+  parseDelayedEvents,
+  groupScheduledByRoom,
 } from './scheduledMessages';
 
 // Minimal MatrixClient stub: records every authedRequest call and returns a
@@ -119,3 +121,61 @@ test('cancel/restart url-encode the delay id', async () => {
   await cancelScheduledMessage(mx, 'a/b c');
   assert.equal(calls[0][1], '/delayed_events/a%2Fb%20c');
 });
+
+test('parseDelayedEvents: Synapse shape, messages only, sendAt from running_since + delay (#322)', () => {
+  const res = {
+    delayed_events: [
+      {
+        delay_id: 'syd_a',
+        room_id: '!r:x',
+        type: 'm.room.message',
+        content: { msgtype: 'm.text', body: 'hi' },
+        delay: 60000,
+        running_since: 1000,
+      },
+      {
+        delay_id: 'syd_call',
+        room_id: '!r:x',
+        type: 'org.matrix.msc3401.call.member',
+        state_key: '_@a:x_D',
+        content: {},
+        delay: 8000,
+        running_since: 1000,
+      },
+      { delay_id: 'syd_bad', room_id: '!r:x', type: 'm.room.message', content: {} },
+      null,
+    ],
+  };
+  assert.deepEqual(parseDelayedEvents(res), [
+    { delayId: 'syd_a', roomId: '!r:x', content: { msgtype: 'm.text', body: 'hi' }, sendAt: 61000 },
+  ]);
+});
+
+test('parseDelayedEvents: MSC `scheduled` shape and garbage', () => {
+  const item = {
+    delay_id: 'd',
+    room_id: '!r:x',
+    type: 'm.room.message',
+    content: { body: 'b' },
+    delay_ms: 5,
+    delayed_since_ts: 10,
+  };
+  assert.equal(parseDelayedEvents({ scheduled: [item] })[0].sendAt, 15);
+  assert.deepEqual(parseDelayedEvents(undefined), []);
+  assert.deepEqual(parseDelayedEvents({ delayed_events: 'nope' }), []);
+});
+
+test('groupScheduledByRoom: groups and sorts by sendAt', () => {
+  const m = (delayId: string, roomId: string, sendAt: number) => ({
+    delayId,
+    roomId,
+    content: {},
+    sendAt,
+  });
+  const g = groupScheduledByRoom([m('b', '!1', 20), m('a', '!1', 10), m('c', '!2', 5)]);
+  assert.deepEqual(
+    g.get('!1')?.map((x) => x.delayId),
+    ['a', 'b'],
+  );
+  assert.equal(g.get('!2')?.length, 1);
+});

src/app/utils/scheduledMessages.ts

@@ -1,4 +1,5 @@
 import { IContent, MatrixClient, Method } from 'matrix-js-sdk';
+import type { ScheduledMessage } from '../state/scheduledMessages';
 
 /**
  * Schedule a message via MSC4140 (delayed messages).
@@ -76,3 +77,61 @@ export async function sendScheduledMessageNow(mx: MatrixClient, delayId: string)
     { prefix: '/_matrix/client/unstable/org.matrix.msc4140' },
   );
 }
+
+type DelayedEventItem = {
+  delay_id?: unknown;
+  room_id?: unknown;
+  type?: unknown;
+  state_key?: unknown;
+  content?: unknown;
+  delay?: unknown;
+  delay_ms?: unknown;
+  running_since?: unknown;
+  delayed_since_ts?: unknown;
+};
+
+/**
+ * [Gitea #322] Pure: the user's pending scheduled messages from an MSC4140
+ * `GET /delayed_events` response. Synapse answers `{ delayed_events: [...] }`;
+ * the current MSC shape is `{ scheduled: [...] }`. Call-membership delayed
+ * events share the endpoint, so only non-state `m.room.message`s are kept.
+ */
+export function parseDelayedEvents(res: unknown): ScheduledMessage[] {
+  if (!res || typeof res !== 'object') return [];
+  const r = res as { delayed_events?: unknown; scheduled?: unknown };
+  const list = Array.isArray(r.delayed_events) ? r.delayed_events : r.scheduled;
+  if (!Array.isArray(list)) return [];
+  const out: ScheduledMessage[] = [];
+  list.forEach((raw: DelayedEventItem) => {
+    if (!raw || typeof raw !== 'object') return;
+    if (raw.type !== 'm.room.message' || raw.state_key !== undefined) return;
+    if (typeof raw.delay_id !== 'string' || typeof raw.room_id !== 'string') return;
+    if (!raw.content || typeof raw.content !== 'object') return;
+    const delay = Number(raw.delay ?? raw.delay_ms);
+    const since = Number(raw.running_since ?? raw.delayed_since_ts);
+    if (!Number.isFinite(delay) || !Number.isFinite(since)) return;
+    out.push({
+      delayId: raw.delay_id,
+      roomId: raw.room_id,
+      content: raw.content as IContent,
+      sendAt: since + delay,
+    });
+  });
+  return out;
+}
+
+/** The user's pending scheduled messages, as the server has them. */
+export async function fetchScheduledMessages(mx: MatrixClient): Promise<ScheduledMessage[]> {
+  const res = await mx.http.authedRequest(Method.Get, '/delayed_events', undefined, undefined, {
+    prefix: '/_matrix/client/unstable/org.matrix.msc4140',
+  });
+  return parseDelayedEvents(res);
+}
+
+/** Group by room, the shape of `scheduledMessagesAtom`. */
+export function groupScheduledByRoom(msgs: ScheduledMessage[]): Map<string, ScheduledMessage[]> {
+  const map = new Map<string, ScheduledMessage[]>();
+  msgs.forEach((m) => map.set(m.roomId, [...(map.get(m.roomId) ?? []), m]));
+  map.forEach((list) => list.sort((a, b) => a.sendAt - b.sendAt));
+  return map;
+}