refactor: Introduce specific ElementCall error type with code

src/room/GroupCallView.tsx

@@ -44,7 +44,7 @@ import { CallEndedView } from "./CallEndedView";
 import { PosthogAnalytics } from "../analytics/PosthogAnalytics";
 import { useProfile } from "../profile/useProfile";
 import { findDeviceByName } from "../utils/media";
-import { ActiveCall, ConnectionLostError } from "./InCallView";
+import { ActiveCall } from "./InCallView";
 import { MUTE_PARTICIPANT_COUNT, type MuteStates } from "./MuteStates";
 import { useMediaDevices } from "../livekit/MediaDevicesContext";
 import { useMatrixRTCSessionMemberships } from "../useMatrixRTCSessionMemberships";
@@ -61,6 +61,7 @@ import { callEventAudioSounds } from "./CallEventAudioRenderer";
 import { useLatest } from "../useLatest";
 import { usePageTitle } from "../usePageTitle";
 import { ErrorView } from "../ErrorView";
+import { ConnectionLostError, ElementCallError } from "../utils/ec-errors.ts";
 
 declare global {
   interface Window {

src/room/InCallView.tsx

@@ -97,13 +97,12 @@ import {
   useSetting,
 } from "../settings/settings";
 import { ReactionsReader } from "../reactions/ReactionsReader";
+import { ConnectionLostError } from "../utils/ec-errors.ts";
 
 const canScreenshare = "getDisplayMedia" in (navigator.mediaDevices ?? {});
 
 const maxTapDurationMs = 400;
 
-export class ConnectionLostError extends Error {}
-
 export interface ActiveCallProps
   extends Omit<InCallViewProps, "vm" | "livekitRoom" | "connState"> {
   e2eeSystem: EncryptionSystem;

src/utils/ec-errors.ts

@@ -0,0 +1,33 @@
+/*
+Copyright 2025 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+export enum ErrorCode {
+  /**
+   * Configuration problem due to no MatrixRTC backend/SFU is exposed via .well-known and no fallback configured.
+   */
+  MISSING_LIVE_KIT_SERVICE_URL = "MISSING_LIVE_KIT_SERVICE_URL",
+  CONNECTION_LOST_ERROR = "CONNECTION_LOST_ERROR",
+  UNKNOWN_ERROR = "UNKNOWN_ERROR",
+}
+
+/**
+ * Structure for errors that occur when using ElementCall.
+ */
+export class ElementCallError extends Error {
+  public code: ErrorCode;
+
+  public constructor(message: string, code: ErrorCode) {
+    super(message);
+    this.code = code;
+  }
+}
+
+export class ConnectionLostError extends ElementCallError {
+  public constructor() {
+    super("Connection lost", ErrorCode.CONNECTION_LOST_ERROR);
+  }
+}