Introduce condigurable auto leave option

src/room/InCallView.tsx

@@ -25,7 +25,11 @@ import useMeasure from "react-use-measure";
 import { type MatrixRTCSession } from "matrix-js-sdk/lib/matrixrtc";
 import classNames from "classnames";
 import { BehaviorSubject, map } from "rxjs";
-import { useObservable } from "observable-hooks";
+import {
+  useObservable,
+  useObservableEagerState,
+  useSubscription,
+} from "observable-hooks";
 import { logger } from "matrix-js-sdk/lib/logger";
 import { RoomAndToDeviceEvents } from "matrix-js-sdk/lib/matrixrtc/RoomAndToDeviceKeyTransport";
 import {
@@ -140,11 +144,11 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
 
   useEffect(() => {
     logger.info(
-      `[Lifecycle] InCallView Component mounted, livekitroom state ${livekitRoom?.state}`,
+      `[Lifecycle] InCallView Component mounted, livekit room state ${livekitRoom?.state}`,
     );
     return (): void => {
       logger.info(
-        `[Lifecycle] InCallView Component unmounted, livekitroom state ${livekitRoom?.state}`,
+        `[Lifecycle] InCallView Component unmounted, livekit room state ${livekitRoom?.state}`,
       );
       livekitRoom
         ?.disconnect()
@@ -166,7 +170,10 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
         props.rtcSession,
         livekitRoom,
         mediaDevices,
-        props.e2eeSystem,
+        {
+          encryptionSystem: props.e2eeSystem,
+          autoLeaveWhenOthersLeft: undefined,
+        },
         connStateObservable$,
         reactionsReader.raisedHands$,
         reactionsReader.reactions$,
@@ -313,6 +320,7 @@ export const InCallView: FC<InCallViewProps> = ({
   const earpieceMode = useBehavior(vm.earpieceMode$);
   const audioOutputSwitcher = useBehavior(vm.audioOutputSwitcher$);
   const switchCamera = useSwitchCamera(vm.localVideo$);
+  useSubscription(vm.autoLeaveWhenOthersLeft$, onLeave);
 
   // Ideally we could detect taps by listening for click events and checking
   // that the pointerType of the event is "touch", but this isn't yet supported

src/state/CallViewModel.ts

@@ -96,6 +96,10 @@ import { calculateDisplayName, shouldDisambiguate } from "../utils/displayname";
 import { type MediaDevices } from "./MediaDevices";
 import { type Behavior } from "./Behavior";
 
+interface CallViewModelOptions {
+  encryptionSystem: EncryptionSystem;
+  autoLeaveWhenOthersLeft?: boolean;
+}
 // How long we wait after a focus switch before showing the real participant
 // list again
 const POST_FOCUS_PARTICIPANT_UPDATE_DELAY_MS = 3000;
@@ -473,49 +477,47 @@ export class CallViewModel extends ViewModel {
     ),
   );
 
+  private readonly memberships$: Observable<CallMembership[]> = merge(
+    // Handle call membership changes.
+    fromEvent(this.matrixRTCSession, MatrixRTCSessionEvent.MembershipsChanged),
+    // Handle room membership changes (and displayname updates)
+    fromEvent(this.matrixRTCSession.room, RoomStateEvent.Members),
+  ).pipe(
+    startWith(this.matrixRTCSession.memberships),
+    map(() => {
+      return this.matrixRTCSession.memberships;
+    }),
+  );
+
   /**
    * Displaynames for each member of the call. This will disambiguate
    * any displaynames that clashes with another member. Only members
    * joined to the call are considered here.
    */
-  public readonly memberDisplaynames$ = this.scope.behavior(
-    merge(
-      // Handle call membership changes.
-      fromEvent(
-        this.matrixRTCSession,
-        MatrixRTCSessionEvent.MembershipsChanged,
-      ),
-      // Handle room membership changes (and displayname updates)
-      fromEvent(this.matrixRTCSession.room, RoomStateEvent.Members),
-    ).pipe(
-      startWith(null),
-      map(() => {
-        const displaynameMap = new Map<string, string>();
-        const { room, memberships } = this.matrixRTCSession;
+  public readonly memberDisplaynames$ = this.memberships$.pipe(
+    map((memberships) => {
+      const displaynameMap = new Map<string, string>();
+      const { room } = this.matrixRTCSession;
 
-        // We only consider RTC members for disambiguation as they are the only visible members.
-        for (const rtcMember of memberships) {
-          const matrixIdentifier = `${rtcMember.sender}:${rtcMember.deviceId}`;
-          const { member } = getRoomMemberFromRtcMember(rtcMember, room);
-          if (!member) {
-            logger.error(
-              "Could not find member for media id:",
-              matrixIdentifier,
-            );
-            continue;
-          }
-          const disambiguate = shouldDisambiguate(member, memberships, room);
-          displaynameMap.set(
-            matrixIdentifier,
-            calculateDisplayName(member, disambiguate),
-          );
+      // We only consider RTC members for disambiguation as they are the only visible members.
+      for (const rtcMember of memberships) {
+        const matrixIdentifier = `${rtcMember.sender}:${rtcMember.deviceId}`;
+        const { member } = getRoomMemberFromRtcMember(rtcMember, room);
+        if (!member) {
+          logger.error("Could not find member for media id:", matrixIdentifier);
+          continue;
         }
-        return displaynameMap;
-      }),
-      // It turns out that doing the disambiguation above is rather expensive on Safari (10x slower
-      // than on Chrome/Firefox). This means it is important that we multicast the result so that we
-      // don't do this work more times than we need to. This is achieved by converting to a behavior:
-    ),
+        const disambiguate = shouldDisambiguate(member, memberships, room);
+        displaynameMap.set(
+          matrixIdentifier,
+          calculateDisplayName(member, disambiguate),
+        );
+      }
+      return displaynameMap;
+    }),
+    // It turns out that doing the disambiguation above is rather expensive on Safari (10x slower
+    // than on Chrome/Firefox). This means it is important that we multicast the result so that we
+    // don't do this work more times than we need to. This is achieved by converting to a behavior:
   );
 
   public readonly handsRaised$ = this.scope.behavior(this.handsRaisedSubject$);
@@ -612,7 +614,7 @@ export class CallViewModel extends ViewModel {
                         indexedMediaId,
                         member,
                         participant,
-                        this.encryptionSystem,
+                        this.options.encryptionSystem,
                         this.livekitRoom,
                         this.memberDisplaynames$.pipe(
                           map((m) => m.get(matrixIdentifier) ?? "[👻]"),
@@ -635,7 +637,7 @@ export class CallViewModel extends ViewModel {
                           screenShareId,
                           member,
                           participant,
-                          this.encryptionSystem,
+                          this.options.encryptionSystem,
                           this.livekitRoom,
                           this.memberDisplaynames$.pipe(
                             map((m) => m.get(matrixIdentifier) ?? "[👻]"),
@@ -676,7 +678,7 @@ export class CallViewModel extends ViewModel {
                               nonMemberId,
                               undefined,
                               participant,
-                              this.encryptionSystem,
+                              this.options.encryptionSystem,
                               this.livekitRoom,
                               this.memberDisplaynames$.pipe(
                                 map(
@@ -726,18 +728,29 @@ export class CallViewModel extends ViewModel {
     ),
   );
 
-  public readonly memberChanges$ = this.userMedia$
-    .pipe(map((mediaItems) => mediaItems.map((m) => m.id)))
-    .pipe(
-      scan<string[], { ids: string[]; joined: string[]; left: string[] }>(
-        (prev, ids) => {
-          const left = prev.ids.filter((id) => !ids.includes(id));
-          const joined = ids.filter((id) => !prev.ids.includes(id));
-          return { ids, joined, left };
-        },
-        { ids: [], joined: [], left: [] },
-      ),
-    );
+  public readonly memberChanges$ = this.userMedia$.pipe(
+    map((mediaItems) => mediaItems.map((m) => m.id)),
+    scan<string[], { ids: string[]; joined: string[]; left: string[] }>(
+      (prev, ids) => {
+        const left = prev.ids.filter((id) => !ids.includes(id));
+        const joined = ids.filter((id) => !prev.ids.includes(id));
+        return { ids, joined, left };
+      },
+      { ids: [], joined: [], left: [] },
+    ),
+  );
+
+  public readonly allOthersLeft$ = this.memberChanges$.pipe(
+    map(({ ids, left }) => ids.length === 0 && left.length > 0),
+    startWith(false),
+    distinctUntilChanged(),
+  );
+
+  public readonly autoLeaveWhenOthersLeft$ = this.allOthersLeft$.pipe(
+    distinctUntilChanged(),
+    filter((leave) => (leave && this.options.autoLeaveWhenOthersLeft) ?? false),
+    map(() => {}),
+  );
 
   /**
    * List of MediaItems that we want to display, that are of type ScreenShare
@@ -1426,7 +1439,7 @@ export class CallViewModel extends ViewModel {
     private readonly matrixRTCSession: MatrixRTCSession,
     private readonly livekitRoom: LivekitRoom,
     private readonly mediaDevices: MediaDevices,
-    private readonly encryptionSystem: EncryptionSystem,
+    private readonly options: CallViewModelOptions,
     private readonly connectionState$: Observable<ECConnectionState>,
     private readonly handsRaisedSubject$: Observable<
       Record<string, RaisedHandInfo>