Rename directory: ext -> extension

extension/src/cast/content.ts

@@ -0,0 +1,48 @@
+/**
+ * Cast Sender SDK page script loaded in place of remote cast_sender
+ * script. Handles API object creation and initializes sender apps.
+ */
+
+import logger from "../lib/logger";
+import { loadScript } from "../lib/utils";
+
+import pageMessaging from "./pageMessaging";
+import CastSDK from "./sdk";
+import { CAST_FRAMEWORK_SCRIPT_URL } from "./urls";
+
+// Create page-accessible API object
+window.chrome.cast = new CastSDK();
+
+let frameworkScriptPromise: Promise<HTMLScriptElement> | undefined;
+
+// Load remote CAF script if requested in script URL params.
+if (document.currentScript) {
+    const currentScript = document.currentScript as HTMLScriptElement;
+    const currentScriptParams = new URLSearchParams(
+        new URL(currentScript.src).search
+    );
+
+    if (currentScriptParams.get("loadCastFramework") === "1") {
+        frameworkScriptPromise = loadScript(CAST_FRAMEWORK_SCRIPT_URL);
+        frameworkScriptPromise.catch(() => {
+            logger.error("Failed to load CAF script!");
+        });
+    }
+}
+
+pageMessaging.page.addListener(async message => {
+    switch (message.subject) {
+        case "cast:instanceCreated": {
+            // If framework API is loading, wait until completed
+            await frameworkScriptPromise;
+
+            // Call page script/framework API script's init function
+            const initFn = window.__onGCastApiAvailable;
+            if (initFn && typeof initFn === "function") {
+                initFn(message.data.isAvailable);
+            }
+
+            break;
+        }
+    }
+});