New group call experience: Starting and ending calls (#9318)

* Create m.room calls in video rooms, and m.prompt calls otherwise

* Terminate a call when the last person leaves

* Hook up the room header button to a unified CallView component

* Write more tests

src/stores/CallStore.ts

@@ -156,6 +156,16 @@ export class CallStore extends AsyncStoreWithClient<{}> {
         return this.calls.get(roomId) ?? null;
     }
 
+    /**
+     * Determines whether the given room has an active call.
+     * @param roomId The room's ID.
+     * @returns Whether the given room has an active call.
+     */
+    public hasActiveCall(roomId: string): boolean {
+        const call = this.get(roomId);
+        return call !== null && this.activeCalls.has(call);
+    }
+
     private onRoom = (room: Room) => this.updateRoom(room);
 
     private onRoomState = (event: MatrixEvent, state: RoomState) => {

src/stores/RoomViewStore.tsx

@@ -50,6 +50,7 @@ import SettingsStore from "../settings/SettingsStore";
 import { SlidingSyncManager } from "../SlidingSyncManager";
 import { awaitRoomDownSync } from "../utils/RoomUpgrade";
 import { UPDATE_EVENT } from "./AsyncStore";
+import { CallStore } from "./CallStore";
 
 const NUM_JOIN_RETRY = 5;
 
@@ -286,6 +287,8 @@ export class RoomViewStore extends EventEmitter {
 
     private async viewRoom(payload: ViewRoomPayload): Promise<void> {
         if (payload.room_id) {
+            const room = MatrixClientPeg.get().getRoom(payload.room_id);
+
             if (payload.metricsTrigger !== null && payload.room_id !== this.state.roomId) {
                 let activeSpace: ViewRoomEvent["activeSpace"];
                 if (SpaceStore.instance.activeSpace === MetaSpace.Home) {
@@ -303,10 +306,11 @@ export class RoomViewStore extends EventEmitter {
                     trigger: payload.metricsTrigger,
                     viaKeyboard: payload.metricsViaKeyboard,
                     isDM: !!DMRoomMap.shared().getUserIdForRoomId(payload.room_id),
-                    isSpace: MatrixClientPeg.get().getRoom(payload.room_id)?.isSpaceRoom(),
+                    isSpace: room?.isSpaceRoom(),
                     activeSpace,
                 });
             }
+
             if (SettingsStore.getValue("feature_sliding_sync") && this.state.roomId !== payload.room_id) {
                 if (this.state.subscribingRoomId && this.state.subscribingRoomId !== payload.room_id) {
                     // unsubscribe from this room, but don't await it as we don't care when this gets done.
@@ -359,8 +363,9 @@ export class RoomViewStore extends EventEmitter {
                 viaServers: payload.via_servers ?? [],
                 wasContextSwitch: payload.context_switch ?? false,
                 viewingCall: payload.view_call ?? (
-                    // Reset to false when switching rooms
-                    payload.room_id === this.state.roomId ? this.state.viewingCall : false
+                    payload.room_id === this.state.roomId
+                        ? this.state.viewingCall
+                        : CallStore.instance.hasActiveCall(payload.room_id)
                 ),
             };