Fix SDK initialization timing issues

ext/src/background/castManager.ts

@@ -169,7 +169,7 @@ const castManager = new (class {
         this.activeInstances.add(instance);
 
         instance.contentPort.postMessage({
-            subject: "cast:initialized",
+            subject: "cast:instanceCreated",
             data: { isAvailable: (await bridge.getInfo()).isVersionCompatible }
         });
 
@@ -349,7 +349,7 @@ const castManager = new (class {
         }
 
         switch (message.subject) {
-            case "main:initializeCast":
+            case "main:initializeCastSdk":
                 instance.apiConfig = message.data.apiConfig;
                 instance.contentPort.postMessage({
                     subject: "cast:receiverAvailabilityUpdated",

ext/src/cast/content.ts

@@ -32,7 +32,7 @@ if (document.currentScript) {
 
 pageMessenging.page.addListener(async message => {
     switch (message.subject) {
-        case "cast:initialized": {
+        case "cast:instanceCreated": {
             // If framework API is loading, wait until completed
             await frameworkScriptPromise;
 

ext/src/cast/export.ts

@@ -65,7 +65,7 @@ export function ensureInit(contextTabId?: number): Promise<CastPort> {
             // castManager -> cast instance
             managerPort.addEventListener("message", ev => {
                 const message = ev.data as Message;
-                if (message.subject === "cast:initialized") {
+                if (message.subject === "cast:instanceCreated") {
                     if (message.data.isAvailable) {
                         resolve(existingPort);
                     } else {
@@ -91,7 +91,7 @@ export function ensureInit(contextTabId?: number): Promise<CastPort> {
             backgroundPort.onMessage.addListener(function onManagerMessage(
                 message: Message
             ) {
-                if (message.subject === "cast:initialized") {
+                if (message.subject === "cast:instanceCreated") {
                     if (message.data.isAvailable) {
                         resolve(pageMessenging.page.messagePort);
                     } else {

ext/src/cast/sdk/index.ts

@@ -54,8 +54,10 @@ export default class {
     #apiConfig?: ApiConfig;
     #sessionRequest?: SessionRequest;
 
+    #isInitialized = false;
+
     /** Current receiver availability. */
-    #receiverAvailability = ReceiverAvailability.UNAVAILABLE;
+    #receiverAvailability?: ReceiverAvailability;
 
     #initializeSuccessCallback?: () => void;
 
@@ -105,10 +107,37 @@ export default class {
 
     #onMessage(message: Message) {
         switch (message.subject) {
-            case "cast:initialized":
+            case "cast:instanceCreated":
                 this.isAvailable = true;
-                this.#initializeSuccessCallback?.();
-                this.#apiConfig?.receiverListener(this.#receiverAvailability);
+                break;
+
+            case "cast:receiverAvailabilityUpdated": {
+                /**
+                 * The first availability update happens after
+                 * initialize is called.
+                 */
+                if (!this.#isInitialized) {
+                    this.#isInitialized = true;
+                    this.#initializeSuccessCallback?.();
+                }
+
+                const availability = message.data.isAvailable
+                    ? ReceiverAvailability.AVAILABLE
+                    : ReceiverAvailability.UNAVAILABLE;
+
+                // If availability has changed, call receiver listeners
+                if (availability !== this.#receiverAvailability) {
+                    this.#receiverAvailability = availability;
+                    this.#apiConfig?.receiverListener(availability);
+                }
+
+                break;
+            }
+
+            case "cast:receiverAction":
+                for (const actionListener of this.#receiverActionListeners) {
+                    actionListener(message.data.receiver, message.data.action);
+                }
                 break;
 
             // Popup closed before session established
@@ -127,6 +156,7 @@ export default class {
              * and data needed to create cast API objects is sent.
              */
             case "cast:sessionCreated": {
+                this.#sessionRequest = undefined;
                 const status = message.data;
 
                 status.receiver.volume = status.volume;
@@ -248,26 +278,6 @@ export default class {
 
                 break;
             }
-
-            case "cast:receiverAvailabilityUpdated": {
-                const availability = message.data.isAvailable
-                    ? ReceiverAvailability.AVAILABLE
-                    : ReceiverAvailability.UNAVAILABLE;
-
-                // If availability has changed, call receiver listeners
-                if (availability !== this.#receiverAvailability) {
-                    this.#receiverAvailability = availability;
-                    this.#apiConfig?.receiverListener(availability);
-                }
-
-                break;
-            }
-
-            case "cast:receiverAction":
-                for (const actionListener of this.#receiverActionListeners) {
-                    actionListener(message.data.receiver, message.data.action);
-                }
-                break;
         }
     }
 
@@ -291,7 +301,7 @@ export default class {
         }
 
         pageMessenging.page.sendMessage({
-            subject: "main:initializeCast",
+            subject: "main:initializeCastSdk",
             data: { apiConfig: this.#apiConfig }
         });
     }

ext/src/messaging.ts

@@ -66,10 +66,19 @@ type ExtMessageDefinitions = {
      * stopped. Used to provide cast API receiver action updates.
      */
     "main:receiverStopped": { deviceId: string };
-    /** Allows the selector popup to send cast NS_RECEIVER messages. */
-    "main:sendReceiverMessage": ReceiverSelectorReceiverMessage;
-    /** Allows the selector popup to send cast NS_MEDIA messages. */
-    "main:sendMediaMessage": ReceiverSelectorMediaMessage;
+
+    /**
+     * Tells the cast manager to provide the cast API instance with
+     * receiver data.
+     */
+    "main:initializeCastSdk": { apiConfig: ApiConfig };
+    "cast:initialized": { isAvailable: boolean };
+
+    /**
+     * Sent to the cast API when a session is requested or stopped via
+     * the extension UI.
+     */
+    "cast:receiverAction": { receiver: Receiver; action: ReceiverAction };
 
     /**
      * Sent from the cast API to trigger receiver selection on session
@@ -81,23 +90,16 @@ type ExtMessageDefinitions = {
     /** Return message to the cast API when a selection is cancelled. */
     "cast:sessionRequestCancelled": undefined;
 
-    /**
-     * Sent to the cast API when a session is requested or stopped via
-     * the extension UI.
-     */
-    "cast:receiverAction": { receiver: Receiver; action: ReceiverAction };
-
-    /**
-     * Tells the cast manager to provide the cast API instance with
-     * receiver data.
-     */
-    "main:initializeCast": { apiConfig: ApiConfig };
-    "cast:initialized": { isAvailable: boolean };
+    "cast:instanceCreated": { isAvailable: boolean };
+    "cast:receiverAvailabilityUpdated": { isAvailable: boolean };
 
     "cast:sessionCreated": CastSessionCreatedDetails & { receiver: Receiver };
     "cast:sessionUpdated": CastSessionUpdatedDetails;
 
-    "cast:receiverAvailabilityUpdated": { isAvailable: boolean };
+    /** Allows the selector popup to send cast NS_RECEIVER messages. */
+    "main:sendReceiverMessage": ReceiverSelectorReceiverMessage;
+    /** Allows the selector popup to send cast NS_MEDIA messages. */
+    "main:sendMediaMessage": ReceiverSelectorMediaMessage;
 };
 
 /**