Fix existing media not set for auto join sessions

ext/src/cast/sdk/Session.ts

@@ -34,7 +34,7 @@ const logger = new Logger("fx_cast [sdk :: cast.Session]");
  * Takes a media object and a media status object and merges the status
  * with the existing media object, updating it with new properties.
  */
-function updateMedia(media: Media, status: MediaStatus) {
+export function updateMedia(media: Media, status: MediaStatus) {
     if (status.currentTime) {
         MediaLastUpdateTimes.set(media, Date.now());
     }
@@ -105,6 +105,11 @@ export const SessionLeaveSuccessCallback = new WeakMap<
     Optional<() => void>
 >();
 
+type SendMediaMessage = (
+    message: DistributiveOmit<SenderMediaMessage, "requestId">
+) => Promise<void>;
+export const SessionSendMediaMessage = new WeakMap<Session, SendMediaMessage>();
+
 /** Creates a Session object and initializes private data. */
 export function createSession(
     sessionArgs: ConstructorParameters<typeof Session>
@@ -113,6 +118,17 @@ export function createSession(
     SessionUpdateListeners.set(session, new Set());
     SessionSendMessageCallbacks.set(session, new Map());
 
+    SessionSendMediaMessage.set(session, message => {
+        return new Promise<void>((resolve, reject) => {
+            session.sendMessage(
+                NS_MEDIA,
+                { ...message, requestId: 0 },
+                resolve,
+                reject
+            );
+        });
+    });
+
     return session;
 }
 
@@ -144,6 +160,13 @@ export default class Session {
         return sendMessageCallback;
     }
 
+    get #sendMediaMessage() {
+        const sendMediaMessage = SessionSendMediaMessage.get(this);
+        if (!sendMediaMessage)
+            throw logger.error("Missing send media message function!");
+        return sendMediaMessage;
+    }
+
     get #leaveSuccessCallback() {
         return SessionLeaveSuccessCallback.get(this);
     }
@@ -208,22 +231,6 @@ export default class Session {
         }
     };
 
-    /**
-     * Sends a media message to the app receiver.
-     */
-    #sendMediaMessage = (
-        message: DistributiveOmit<SenderMediaMessage, "requestId">
-    ) => {
-        return new Promise<void>((resolve, reject) => {
-            this.sendMessage(
-                NS_MEDIA,
-                { ...message, requestId: 0 },
-                resolve,
-                reject
-            );
-        });
-    };
-
     #sendReceiverMessage = (
         message: DistributiveOmit<SenderMessage, "requestId">
     ) => {

ext/src/cast/sdk/index.ts

@@ -35,11 +35,14 @@ import Session, {
     createSession,
     SessionLeaveSuccessCallback,
     SessionMessageListeners,
+    SessionSendMediaMessage,
     SessionSendMessageCallbacks,
-    SessionUpdateListeners
+    SessionUpdateListeners,
+    updateMedia
 } from "./Session";
 
 import * as media from "./media";
+import { createMedia } from "./media/Media";
 
 const logger = new Logger("fx_cast [sdk]");
 
@@ -179,6 +182,16 @@ export default class {
                 session.statusText = status.statusText;
                 session.transportId = status.transportId;
 
+                if (status.media) {
+                    const media = createMedia(
+                        [status.sessionId, status.media.mediaSessionId],
+                        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+                        SessionSendMediaMessage.get(session)!
+                    );
+                    updateMedia(media, status.media);
+                    session.media = [media];
+                }
+
                 this.#sessions.set(session.sessionId, session);
 
                 /**