feat: implement remote homeserver handling for LiveKit calls

src/app/features/call/CallService.ts

@@ -22,7 +22,14 @@ import {
   LiveKitJWTResponse,
   CallMemberEventContent,
 } from './types';
-import { fetchLiveKitJWT, fetchWellKnownWithRTC, getLiveKitFocus, requestOpenIdToken } from './useRtcConfig';
+import { 
+  fetchLiveKitJWT, 
+  fetchWellKnownWithRTC, 
+  getLiveKitFocus, 
+  requestOpenIdToken,
+  fetchLiveKitJWTFromServers,
+  getLiveKitHomeserverPriority,
+} from './useRtcConfig';
 import { getAudioSettings, SCREEN_SHARE_RESOLUTIONS, SCREEN_SHARE_BITRATES } from '../settings/audio/Audio';
 import { getCallSounds, CallSoundType } from './CallSounds';
 
@@ -293,23 +300,48 @@ export class CallService {
     });
 
     try {
-      // Step 1: Get an OpenID token from the Matrix homeserver
-      const openIdToken = await requestOpenIdToken(
+      // Step 1: Get room and determine which homeservers to try
+      const room = this.matrixClient.getRoom(roomId);
+      if (!room) {
+        throw new Error(`Room ${roomId} not found`);
+      }
+
+      const homeserverPriority = getLiveKitHomeserverPriority(
+        room,
         this.config.homeserverBaseUrl,
-        this.config.userId,
-        this.config.accessToken
+        this.config.userId
       );
 
-      // Step 2: Exchange OpenID token for LiveKit JWT
-      console.log('Requesting LiveKit JWT for Matrix room:', roomId);
-      this.livekitJwt = await fetchLiveKitJWT(
-        this.config.livekitServiceUrl,
+      console.log('Trying homeservers in order:', homeserverPriority);
+
+      // Step 2: Try fetching LiveKit JWT from homeservers in priority order
+      const result = await fetchLiveKitJWTFromServers(
+        homeserverPriority,
         roomId,
         this.config.userId,
         this.config.deviceId,
-        openIdToken
+        this.config.accessToken
       );
 
+      if (!result) {
+        throw new Error('Failed to get LiveKit JWT from any homeserver');
+      }
+
+      this.livekitJwt = result.jwt;
+      
+      // Track if using remote homeserver
+      const userHomeserverDomain = this.config.homeserverBaseUrl
+        .replace('https://', '')
+        .replace('http://', '');
+      const usedHomeserverDomain = result.homeserver
+        .replace('https://', '')
+        .replace('http://', '');
+      
+      if (usedHomeserverDomain !== userHomeserverDomain) {
+        this.activeCall!.livekitHomeserver = result.homeserver;
+        console.log(`Using remote homeserver for LiveKit: ${result.homeserver}`);
+      }
+
       console.log('Got LiveKit JWT, connecting to:', this.livekitJwt.url);
       console.log('LiveKit JWT response:', JSON.stringify(this.livekitJwt));
 
@@ -918,6 +950,22 @@ export class CallService {
     return this.livekitRoom;
   }
 
+  /**
+   * Checks if the current call is using a remote homeserver for LiveKit
+   * @returns true if using a different homeserver than the user's
+   */
+  isUsingRemoteHomeserver(): boolean {
+    return !!this.activeCall?.livekitHomeserver;
+  }
+
+  /**
+   * Gets the homeserver being used for LiveKit (if remote)
+   * @returns The remote homeserver URL, or undefined if using user's homeserver
+   */
+  getLiveKitHomeserver(): string | undefined {
+    return this.activeCall?.livekitHomeserver;
+  }
+
   /**
    * Starts screen sharing with configurable resolution and bitrate
    * @returns true if screen share started successfully