[core] fix download postmessage logic

Author: velzie

src/client/events.ts

@@ -5,7 +5,7 @@ export class ScramjetGlobalDownloadEvent extends Event {
 	type = "download";
 	constructor(
 		public filename: string,
-		public body: ArrayBuffer
+		public body: ReadableStream<Uint8Array>
 	) {
 		super("download");
 	}

src/controller/index.ts

@@ -10,6 +10,7 @@ import { ScramjetFrame } from "@/controller/frame";
 import { MessageW2C } from "@/worker";
 import {
 	ScramjetEvents,
+	ScramjetGlobalDownloadEvent,
 	ScramjetGlobalEvent,
 	ScramjetGlobalEvents,
 } from "@client/events";
@@ -94,11 +95,14 @@ export class ScramjetController extends EventTarget {
 		});
 		dbg.log("config loaded");
 
-		serviceWorker.addEventListener("message", (e) => {
+		navigator.serviceWorker.addEventListener("message", (e) => {
 			if (!("scramjet$type" in e.data)) return;
 			const data: MessageW2C = e.data;
 
 			if (data.scramjet$type === "download") {
+				this.dispatchEvent(
+					new ScramjetGlobalDownloadEvent(data.filename, data.body)
+				);
 			}
 		});
 	}

src/worker/fetch.ts

@@ -479,14 +479,25 @@ async function handleResponse(
 				}
 			}
 
-			const ab = await response.arrayBuffer();
-			client.postMessage(
+			// there's no reliable way of finding the top level client that made the request
+			// just take the first one and hope
+			let clis = await clients.matchAll({
+				type: "window",
+			});
+			// only want controller windows
+			clis = clis.filter((e) => !e.url.includes(config.prefix));
+			if (clis.length < 1) {
+				throw Error(
+					"couldn't find a controller client to dispatch download to"
+				);
+			}
+			clis[0].postMessage(
 				{
 					scramjet$type: "download",
 					filename,
-					body: ab,
+					body: response.body,
 				} as MessageW2C,
-				[ab]
+				[response.body]
 			);
 
 			// endless vortex reference

src/worker/index.ts

@@ -161,12 +161,11 @@ type ConfigMessage = {
 };
 
 type DownloadMessage = {
-	$scramjet$type: "download";
+	scramjet$type: "download";
 	filename: string;
-	body: ArrayBuffer;
+	body: ReadableStream<Uint8Array>;
 };
 type MessageCommon = {
-	scramjet$type: string;
 	scramjet$token?: number;
 };