Make UI react instantly to hanging up but also wait for leave sound

This ensures that we don't see a mistaken 'reconnecting' toast while we're hanging up (and also that the leave sound gets a chance to play in widgets once again).

src/room/GroupCallView.tsx

@@ -41,7 +41,6 @@ import { ActiveCall } from "./InCallView";
 import { type MuteStates } from "../state/MuteStates";
 import { useMediaDevices } from "../MediaDevicesContext";
 import { useMatrixRTCSessionMemberships } from "../useMatrixRTCSessionMemberships";
-import { leaveRTCSession } from "../rtcSessionHelpers";
 import {
   saveKeyForRoom,
   useRoomEncryptionSystem,
@@ -50,7 +49,12 @@ import { useRoomAvatar } from "./useRoomAvatar";
 import { useRoomName } from "./useRoomName";
 import { useJoinRule } from "./useJoinRule";
 import { InviteModal } from "./InviteModal";
-import { HeaderStyle, type UrlParams, useUrlParams } from "../UrlParams";
+import {
+  getUrlParams,
+  HeaderStyle,
+  type UrlParams,
+  useUrlParams,
+} from "../UrlParams";
 import { E2eeType } from "../e2ee/e2eeType";
 import { useAudioContext } from "../useAudioContext";
 import {
@@ -322,37 +326,62 @@ export const GroupCallView: FC<Props> = ({
       setJoined(false);
       setLeft(true);
       const audioPromise = leaveSoundContext.current?.playSound(playSound);
-      // In embedded/widget mode the iFrame will be killed right after the call ended prohibiting the posthog event from getting sent,
-      // therefore we want the event to be sent instantly without getting queued/batched.
-      const sendInstantly = !!widget;
-      // we need to wait until the callEnded event is tracked on posthog.
-      // Otherwise the iFrame gets killed before the callEnded event got tracked.
+      // We need to wait until the callEnded event is tracked on PostHog,
+      // otherwise the iframe may get killed first.
       const posthogRequest = new Promise((resolve) => {
+        // To increase the likelihood of the PostHog event being sent out in
+        // widget mode before the iframe is killed, we ask it to skip the
+        // usual queuing/batching of requests.
+        const sendInstantly = widget !== null;
         PosthogAnalytics.instance.eventCallEnded.track(
           room.roomId,
           rtcSession.memberships.length,
           sendInstantly,
-
           rtcSession,
         );
+        // Unfortunately the PostHog library provides no way to await the
+        // tracking of an event, but we don't really want it to hold up the
+        // closing of the widget that long anyway, so giving it 10 ms will do.
         window.setTimeout(resolve, 10);
       });
 
       void Promise.all([audioPromise, posthogRequest])
-        .then(() => {
+        .catch((e) =>
+          logger.error(
+            "Failed to play leave audio and/or send PostHog leave event",
+            e,
+          ),
+        )
+        .then(async () => {
           if (
             !isPasswordlessUser &&
             !confineToRoom &&
             !PosthogAnalytics.instance.isEnabled()
-          ) {
+          )
             void navigate("/");
+
+          if (widget) {
+            // After this point the iframe could die at any moment!
+            try {
+              await widget.api.setAlwaysOnScreen(false);
+            } catch (e) {
+              logger.error(
+                "Failed to set call widget `alwaysOnScreen` to false",
+                e,
+              );
+            }
+            // On a normal user hangup we can shut down and close the widget. But if an
+            // error occurs we should keep the widget open until the user reads it.
+            if (reason === "user" && !getUrlParams().returnToLobby) {
+              try {
+                await widget.api.transport.send(ElementWidgetActions.Close, {});
+              } catch (e) {
+                logger.error("Failed to send close action", e);
+              }
+              widget.api.transport.stop();
+            }
           }
-        })
-        .catch(() =>
-          logger.error(
-            "could failed to play leave audio or send posthog leave event",
-          ),
-        );
+        });
     },
     [
       setJoined,
@@ -367,24 +396,11 @@ export const GroupCallView: FC<Props> = ({
   );
 
   useEffect(() => {
-    if (widget && joined) {
+    if (widget && joined)
       // set widget to sticky once joined.
       widget.api.setAlwaysOnScreen(true).catch((e) => {
         logger.error("Error calling setAlwaysOnScreen(true)", e);
       });
-
-      const onHangup = (ev: CustomEvent<IWidgetApiRequest>): void => {
-        widget.api.transport.reply(ev.detail, {});
-        // Only sends matrix leave event. The Livekit session will disconnect once the ActiveCall-view unmounts.
-        leaveRTCSession(rtcSession, "user").catch((e) => {
-          logger.error("Failed to leave RTC session", e);
-        });
-      };
-      widget.lazyActions.once(ElementWidgetActions.HangupCall, onHangup);
-      return (): void => {
-        widget.lazyActions.off(ElementWidgetActions.HangupCall, onHangup);
-      };
-    }
   }, [widget, joined, rtcSession]);
 
   const joinRule = useJoinRule(room);

src/room/InCallView.tsx

@@ -151,7 +151,7 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
     );
     setVm(vm);
 
-    const sub = vm.left$.subscribe(props.onLeft);
+    const sub = vm.leave$.subscribe(props.onLeft);
     return (): void => {
       vm.destroy();
       sub.unsubscribe();
@@ -798,7 +798,7 @@ export const InCallView: FC<InCallViewProps> = ({
     <EndCallButton
       key="end_call"
       onClick={function (): void {
-        vm.leave();
+        vm.hangup();
       }}
       onTouchEnd={onControlsTouchEnd}
       data-testid="incall_leave"

src/state/CallViewModel.ts

@@ -57,6 +57,7 @@ import {
   switchScan,
   take,
   takeUntil,
+  tap,
   throttleTime,
   timer,
 } from "rxjs";
@@ -117,16 +118,16 @@ import { constant, type Behavior } from "./Behavior";
 import {
   enterRTCSession,
   getLivekitAlias,
-  leaveRTCSession,
   makeFocus,
 } from "../rtcSessionHelpers";
 import { E2eeType } from "../e2ee/e2eeType";
 import { MatrixKeyProvider } from "../e2ee/matrixKeyProvider";
 import { Connection, PublishConnection } from "./Connection";
 import { type MuteStates } from "./MuteStates";
-import { PosthogAnalytics } from "../analytics/PosthogAnalytics";
 import { getUrlParams } from "../UrlParams";
 import { type ProcessorState } from "../livekit/TrackProcessorContext";
+import { ElementWidgetActions, widget } from "../widget";
+import { IWidgetApiRequest } from "matrix-widget-api";
 
 export interface CallViewModelOptions {
   encryptionSystem: EncryptionSystem;
@@ -554,19 +555,6 @@ export class CallViewModel extends ViewModel {
     this.join$.next();
   }
 
-  private readonly leave$ = new Subject<
-    "decline" | "timeout" | "user" | "allOthersLeft"
-  >();
-
-  public leave(): void {
-    this.leave$.next("user");
-  }
-
-  private readonly _left$ = new Subject<
-    "decline" | "timeout" | "user" | "allOthersLeft"
-  >();
-  public left$ = this._left$.asObservable();
-
   private readonly connectionInstructions$ = this.join$.pipe(
     switchMap(() => this.remoteConnections$),
     startWith(new Map<string, Connection>()),
@@ -1154,7 +1142,7 @@ export class CallViewModel extends ViewModel {
   );
 
   private readonly allOthersLeft$ = this.matrixUserChanges$.pipe(
-    map(({ userIds, leftUserIds }) => {
+    filter(({ userIds, leftUserIds }) => {
       if (!this.userId) {
         logger.warn("Could not access user ID to compute allOthersLeft");
         return false;
@@ -1163,12 +1151,40 @@ export class CallViewModel extends ViewModel {
         userIds.size === 1 && userIds.has(this.userId) && leftUserIds.size > 0
       );
     }),
-    startWith(false),
+    map(() => "allOthersLeft" as const),
   );
 
-  public readonly autoLeave$ = this.options.autoLeaveWhenOthersLeft
-    ? this.allOthersLeft$
-    : NEVER;
+  // Public for testing
+  public readonly autoLeave$ = merge(
+    this.options.autoLeaveWhenOthersLeft ? this.allOthersLeft$ : NEVER,
+    this.callPickupState$.pipe(
+      filter((state) => state === "timeout" || state === "decline"),
+    ),
+  );
+
+  private readonly userHangup$ = new Subject<void>();
+  public hangup(): void {
+    this.userHangup$.next();
+  }
+
+  private readonly widgetHangup$ =
+    widget === null
+      ? NEVER
+      : (
+          fromEvent(
+            widget.lazyActions,
+            ElementWidgetActions.HangupCall,
+          ) as Observable<[CustomEvent<IWidgetApiRequest>]>
+        ).pipe(tap(([ev]) => widget!.api.transport.reply(ev.detail, {})));
+
+  public readonly leave$: Observable<
+    "user" | "timeout" | "decline" | "allOthersLeft"
+  > = merge(
+    this.autoLeave$,
+    merge(this.userHangup$, this.widgetHangup$).pipe(
+      map(() => "user" as const),
+    ),
+  );
 
   /**
    * List of MediaItems that we want to display, that are of type ScreenShare
@@ -1929,34 +1945,17 @@ export class CallViewModel extends ViewModel {
         );
       });
 
-    this.allOthersLeft$
-      .pipe(
-        this.scope.bind(),
-        filter((l) => (l && this.options.autoLeaveWhenOthersLeft) ?? false),
-        distinctUntilChanged(),
-      )
-      .subscribe(() => {
-        this.leave$.next("allOthersLeft");
-      });
-
-    this.callPickupState$.pipe(this.scope.bind()).subscribe((state) => {
-      if (state === "timeout" || state === "decline") {
-        this.leave$.next(state);
-      }
-    });
-
-    this.leave$.pipe(this.scope.bind()).subscribe((reason) => {
-      const { confineToRoom } = this.urlParams;
-      leaveRTCSession(this.matrixRTCSession, "user")
-        // Only sends matrix leave event. The Livekit session will disconnect once the ActiveCall-view unmounts.
-        .then(() => {
-          if (!confineToRoom && !PosthogAnalytics.instance.isEnabled()) {
-            this._left$.next(reason);
-          }
-        })
-        .catch((e) => {
-          logger.error("Error leaving RTC session", e);
-        });
+    this.leave$.pipe(this.scope.bind()).subscribe(() => {
+      // Only sends Matrix leave event. The LiveKit session will disconnect once, uh...
+      // (TODO-MULTI-SFU does anything actually cause it to disconnect?)
+      void this.matrixRTCSession
+        .leaveRoomSession()
+        .catch((e) => logger.error("Error leaving RTC session", e))
+        .then(async () =>
+          widget?.api.transport
+            .send(ElementWidgetActions.HangupCall, {})
+            .catch((e) => logger.error("Failed to send hangup action", e)),
+        );
     });
 
     // Pause upstream of all local media tracks when we're disconnected from