Refactor LegacyCallHandler event emitter to use TypedEventEmitter (#29008)

* Switch LegacyCallHandler over to TypedEventEmitter and use emits to notify consumers of protocol support updates

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Add test for dialpad

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

---------

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

playwright/e2e/voip/pstn.spec.ts

@@ -0,0 +1,31 @@
+/*
+Copyright 2025 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { test, expect } from "../../element-web-test";
+
+test.describe("PSTN", () => {
+    test.beforeEach(async ({ page }) => {
+        // Mock the third party protocols endpoint to look like the HS has PSTN support
+        await page.route("**/_matrix/client/v3/thirdparty/protocols", async (route) => {
+            await route.fulfill({
+                status: 200,
+                json: {
+                    "im.vector.protocol.pstn": {},
+                },
+            });
+        });
+    });
+
+    test("should render dialpad as expected", { tag: "@screenshot" }, async ({ page, user, toasts }) => {
+        await toasts.rejectToast("Notifications");
+        await toasts.assertNoToasts();
+
+        await expect(page.locator(".mx_LeftPanel_filterContainer")).toMatchScreenshot("dialpad-trigger.png");
+        await page.getByLabel("Open dial pad").click();
+        await expect(page.locator(".mx_Dialog")).toMatchScreenshot("dialpad.png");
+    });
+});

src/LegacyCallHandler.tsx

@@ -10,7 +10,7 @@ Please see LICENSE files in the repository root for full details.
 */
 
 import React from "react";
-import { MatrixError, RuleId, TweakName, SyncState } from "matrix-js-sdk/src/matrix";
+import { MatrixError, RuleId, TweakName, SyncState, TypedEventEmitter } from "matrix-js-sdk/src/matrix";
 import {
     CallError,
     CallErrorCode,
@@ -22,7 +22,6 @@ import {
     MatrixCall,
 } from "matrix-js-sdk/src/webrtc/call";
 import { logger } from "matrix-js-sdk/src/logger";
-import EventEmitter from "events";
 import { PushProcessor } from "matrix-js-sdk/src/pushprocessor";
 import { CallEventHandlerEvent } from "matrix-js-sdk/src/webrtc/callEventHandler";
 
@@ -137,14 +136,23 @@ export enum LegacyCallHandlerEvent {
     CallChangeRoom = "call_change_room",
     SilencedCallsChanged = "silenced_calls_changed",
     CallState = "call_state",
+    ProtocolSupport = "protocol_support",
 }
 
+type EventEmitterMap = {
+    [LegacyCallHandlerEvent.CallsChanged]: (calls: Map<string, MatrixCall>) => void;
+    [LegacyCallHandlerEvent.CallChangeRoom]: (call: MatrixCall) => void;
+    [LegacyCallHandlerEvent.SilencedCallsChanged]: (calls: Set<string>) => void;
+    [LegacyCallHandlerEvent.CallState]: (mappedRoomId: string | null, status: CallState) => void;
+    [LegacyCallHandlerEvent.ProtocolSupport]: () => void;
+};
+
 /**
  * LegacyCallHandler manages all currently active calls. It should be used for
  * placing, answering, rejecting and hanging up calls. It also handles ringing,
  * PSTN support and other things.
  */
-export default class LegacyCallHandler extends EventEmitter {
+export default class LegacyCallHandler extends TypedEventEmitter<LegacyCallHandlerEvent, EventEmitterMap> {
     private calls = new Map<string, MatrixCall>(); // roomId -> call
     // Calls started as an attended transfer, ie. with the intention of transferring another
     // call with a different party to this one.
@@ -271,15 +279,13 @@ export default class LegacyCallHandler extends EventEmitter {
                 this.supportsPstnProtocol = null;
             }
 
-            dis.dispatch({ action: Action.PstnSupportUpdated });
-
             if (protocols[PROTOCOL_SIP_NATIVE] !== undefined && protocols[PROTOCOL_SIP_VIRTUAL] !== undefined) {
                 this.supportsSipNativeVirtual = Boolean(
                     protocols[PROTOCOL_SIP_NATIVE] && protocols[PROTOCOL_SIP_VIRTUAL],
                 );
             }
 
-            dis.dispatch({ action: Action.VirtualRoomSupportUpdated });
+            this.emit(LegacyCallHandlerEvent.ProtocolSupport);
         } catch (e) {
             if (maxTries === 1) {
                 logger.log("Failed to check for protocol support and no retries remain: assuming no support", e);
@@ -296,8 +302,8 @@ export default class LegacyCallHandler extends EventEmitter {
         return !!SdkConfig.getObject("voip")?.get("obey_asserted_identity");
     }
 
-    public getSupportsPstnProtocol(): boolean | null {
-        return this.supportsPstnProtocol;
+    public getSupportsPstnProtocol(): boolean {
+        return this.supportsPstnProtocol ?? false;
     }
 
     public getSupportsVirtualRooms(): boolean | null {
@@ -568,6 +574,7 @@ export default class LegacyCallHandler extends EventEmitter {
         if (!mappedRoomId || !this.matchesCallForThisRoom(call)) return;
 
         this.setCallState(call, newState);
+        // XXX: this is used by the IPC into Electron to keep device awake
         dis.dispatch({
             action: "call_state",
             room_id: mappedRoomId,

src/components/structures/LeftPanel.tsx

@@ -13,7 +13,7 @@ import classNames from "classnames";
 import dis from "../../dispatcher/dispatcher";
 import { _t } from "../../languageHandler";
 import RoomList from "../views/rooms/RoomList";
-import LegacyCallHandler from "../../LegacyCallHandler";
+import LegacyCallHandler, { LegacyCallHandlerEvent } from "../../LegacyCallHandler";
 import { HEADER_HEIGHT } from "../views/rooms/RoomSublist";
 import { Action } from "../../dispatcher/actions";
 import RoomSearch from "./RoomSearch";
@@ -51,6 +51,7 @@ enum BreadcrumbsMode {
 interface IState {
     showBreadcrumbs: BreadcrumbsMode;
     activeSpace: SpaceKey;
+    supportsPstnProtocol: boolean;
 }
 
 export default class LeftPanel extends React.Component<IProps, IState> {
@@ -65,6 +66,7 @@ export default class LeftPanel extends React.Component<IProps, IState> {
         this.state = {
             activeSpace: SpaceStore.instance.activeSpace,
             showBreadcrumbs: LeftPanel.breadcrumbsMode,
+            supportsPstnProtocol: LegacyCallHandler.instance.getSupportsPstnProtocol(),
         };
     }
 
@@ -76,6 +78,7 @@ export default class LeftPanel extends React.Component<IProps, IState> {
         BreadcrumbsStore.instance.on(UPDATE_EVENT, this.onBreadcrumbsUpdate);
         RoomListStore.instance.on(LISTS_UPDATE_EVENT, this.onBreadcrumbsUpdate);
         SpaceStore.instance.on(UPDATE_SELECTED_SPACE, this.updateActiveSpace);
+        LegacyCallHandler.instance.on(LegacyCallHandlerEvent.ProtocolSupport, this.updateProtocolSupport);
 
         if (this.listContainerRef.current) {
             UIStore.instance.trackElementDimensions("ListContainer", this.listContainerRef.current);
@@ -90,6 +93,7 @@ export default class LeftPanel extends React.Component<IProps, IState> {
         BreadcrumbsStore.instance.off(UPDATE_EVENT, this.onBreadcrumbsUpdate);
         RoomListStore.instance.off(LISTS_UPDATE_EVENT, this.onBreadcrumbsUpdate);
         SpaceStore.instance.off(UPDATE_SELECTED_SPACE, this.updateActiveSpace);
+        LegacyCallHandler.instance.off(LegacyCallHandlerEvent.ProtocolSupport, this.updateProtocolSupport);
         UIStore.instance.stopTrackingElementDimensions("ListContainer");
         UIStore.instance.removeListener("ListContainer", this.refreshStickyHeaders);
         this.listContainerRef.current?.removeEventListener("scroll", this.onScroll);
@@ -101,6 +105,10 @@ export default class LeftPanel extends React.Component<IProps, IState> {
         }
     }
 
+    private updateProtocolSupport = (): void => {
+        this.setState({ supportsPstnProtocol: LegacyCallHandler.instance.getSupportsPstnProtocol() });
+    };
+
     private updateActiveSpace = (activeSpace: SpaceKey): void => {
         this.setState({ activeSpace });
     };
@@ -330,9 +338,8 @@ export default class LeftPanel extends React.Component<IProps, IState> {
     private renderSearchDialExplore(): React.ReactNode {
         let dialPadButton: JSX.Element | undefined;
 
-        // If we have dialer support, show a button to bring up the dial pad
-        // to start a new call
-        if (LegacyCallHandler.instance.getSupportsPstnProtocol()) {
+        // If we have dialer support, show a button to bring up the dial pad to start a new call
+        if (this.state.supportsPstnProtocol) {
             dialPadButton = (
                 <AccessibleButton
                     className={classNames("mx_LeftPanel_dialPadButton", {})}

src/components/structures/RoomView.tsx

@@ -1082,7 +1082,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         }
     };
 
-    private onCallState = (roomId: string): void => {
+    private onCallState = (roomId: string | null): void => {
         // don't filter out payloads for room IDs other than props.room because
         // we may be interested in the conf 1:1 room
 

src/components/views/rooms/RoomList.tsx

@@ -6,7 +6,7 @@ SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Com
 Please see LICENSE files in the repository root for full details.
 */
 
-import { EventType, RoomType, Room } from "matrix-js-sdk/src/matrix";
+import { EventType, Room, RoomType } from "matrix-js-sdk/src/matrix";
 import React, { ComponentType, createRef, ReactComponentElement, SyntheticEvent } from "react";
 
 import { IState as IRovingTabIndexState, RovingTabIndexProvider } from "../../../accessibility/RovingTabIndex";
@@ -56,6 +56,7 @@ import { KeyBindingAction } from "../../../accessibility/KeyboardShortcuts";
 import { getKeyBindingsManager } from "../../../KeyBindingsManager";
 import AccessibleButton from "../elements/AccessibleButton";
 import { Landmark, LandmarkNavigation } from "../../../accessibility/LandmarkNavigation";
+import LegacyCallHandler, { LegacyCallHandlerEvent } from "../../../LegacyCallHandler.tsx";
 
 interface IProps {
     onKeyDown: (ev: React.KeyboardEvent, state: IRovingTabIndexState) => void;
@@ -440,6 +441,7 @@ export default class RoomList extends React.PureComponent<IProps, IState> {
         SdkContextClass.instance.roomViewStore.on(UPDATE_EVENT, this.onRoomViewStoreUpdate);
         SpaceStore.instance.on(UPDATE_SUGGESTED_ROOMS, this.updateSuggestedRooms);
         RoomListStore.instance.on(LISTS_UPDATE_EVENT, this.updateLists);
+        LegacyCallHandler.instance.on(LegacyCallHandlerEvent.ProtocolSupport, this.updateProtocolSupport);
         this.updateLists(); // trigger the first update
     }
 
@@ -448,8 +450,13 @@ export default class RoomList extends React.PureComponent<IProps, IState> {
         RoomListStore.instance.off(LISTS_UPDATE_EVENT, this.updateLists);
         defaultDispatcher.unregister(this.dispatcherRef);
         SdkContextClass.instance.roomViewStore.off(UPDATE_EVENT, this.onRoomViewStoreUpdate);
+        LegacyCallHandler.instance.off(LegacyCallHandlerEvent.ProtocolSupport, this.updateProtocolSupport);
     }
 
+    private updateProtocolSupport = (): void => {
+        this.updateLists();
+    };
+
     private onRoomViewStoreUpdate = (): void => {
         this.setState({
             currentRoomId: SdkContextClass.instance.roomViewStore.getRoomId() ?? undefined,
@@ -471,8 +478,6 @@ export default class RoomList extends React.PureComponent<IProps, IState> {
                     metricsViaKeyboard: true,
                 });
             }
-        } else if (payload.action === Action.PstnSupportUpdated) {
-            this.updateLists();
         }
     };
 

src/dispatcher/actions.ts

@@ -135,20 +135,6 @@ export enum Action {
      */
     OpenDialPad = "open_dial_pad",
 
-    /**
-     * Fired when CallHandler has checked for PSTN protocol support
-     * payload: none
-     * XXX: Is an action the right thing for this?
-     */
-    PstnSupportUpdated = "pstn_support_updated",
-
-    /**
-     * Similar to PstnSupportUpdated, fired when CallHandler has checked for virtual room support
-     * payload: none
-     * XXX: Ditto
-     */
-    VirtualRoomSupportUpdated = "virtual_room_support_updated",
-
     /**
      * Fired when an upload has started. Should be used with UploadStartedPayload.
      */