Remove blob URL dead code and clean up more frontend code (#2199)

frontend/src/editor.ts

@@ -0,0 +1,87 @@
+// import { panicProxy } from "@graphite/utility-functions/panic-proxy";
+import { type JsMessageType } from "@graphite/messages";
+import { createSubscriptionRouter, type SubscriptionRouter } from "@graphite/subscription-router";
+import init, { setRandomSeed, wasmMemory, EditorHandle } from "@graphite-frontend/wasm/pkg/graphite_wasm.js";
+
+export type Editor = {
+	raw: WebAssembly.Memory;
+	handle: EditorHandle;
+	subscriptions: SubscriptionRouter;
+};
+
+// `wasmImport` starts uninitialized because its initialization needs to occur asynchronously, and thus needs to occur by manually calling and awaiting `initWasm()`
+let wasmImport: WebAssembly.Memory | undefined;
+
+// Should be called asynchronously before `createEditor()`.
+export async function initWasm() {
+	// Skip if the WASM module is already initialized
+	if (wasmImport !== undefined) return;
+
+	// Import the WASM module JS bindings and wrap them in the panic proxy
+	// eslint-disable-next-line import/no-cycle
+	const wasm = await init();
+	for (const [name, f] of Object.entries(wasm)) {
+		if (name.startsWith("__node_registry")) f();
+	}
+
+	wasmImport = await wasmMemory();
+	// eslint-disable-next-line @typescript-eslint/no-explicit-any
+	(window as any).imageCanvases = {};
+
+	// Provide a random starter seed which must occur after initializing the WASM module, since WASM can't generate its own random numbers
+	const randomSeedFloat = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
+	const randomSeed = BigInt(randomSeedFloat);
+	setRandomSeed(randomSeed);
+}
+
+// Should be called after running `initWasm()` and its promise resolving.
+export function createEditor(): Editor {
+	// Raw: object containing several callable functions from `editor_api.rs` defined directly on the WASM module, not the `EditorHandle` struct (generated by wasm-bindgen)
+	if (!wasmImport) throw new Error("Editor WASM backend was not initialized at application startup");
+	const raw: WebAssembly.Memory = wasmImport;
+
+	// Handle: object containing many functions from `editor_api.rs` that are part of the `EditorHandle` struct (generated by wasm-bindgen)
+	const handle: EditorHandle = new EditorHandle((messageType: JsMessageType, messageData: Record<string, unknown>) => {
+		// This callback is called by WASM when a FrontendMessage is received from the WASM wrapper `EditorHandle`
+		// We pass along the first two arguments then add our own `raw` and `handle` context for the last two arguments
+		subscriptions.handleJsMessage(messageType, messageData, raw, handle);
+	});
+
+	// eslint-disable-next-line @typescript-eslint/no-explicit-any
+	(window as any).editorHandle = handle;
+
+	// Subscriptions: allows subscribing to messages in JS that are sent from the WASM backend
+	const subscriptions: SubscriptionRouter = createSubscriptionRouter();
+
+	// Check if the URL hash fragment has any demo artwork to be loaded
+	(async () => {
+		const demoArtwork = window.location.hash.trim().match(/#demo\/(.*)/)?.[1];
+		if (!demoArtwork) return;
+
+		try {
+			const url = new URL(`/${demoArtwork}.graphite`, document.location.href);
+			const data = await fetch(url);
+			if (!data.ok) throw new Error();
+
+			const filename = url.pathname.split("/").pop() || "Untitled";
+			const content = await data.text();
+			handle.openDocumentFile(filename, content);
+
+			// Remove the hash fragment from the URL
+			history.replaceState("", "", `${window.location.pathname}${window.location.search}`);
+		} catch {
+			// Do nothing
+		}
+	})();
+
+	return { raw, handle, subscriptions };
+}
+
+// TODO: Find a better way to do this, since no other code takes this approach.
+// TODO: Then, delete the `(window as any).editorHandle = handle;` line above.
+// This function is called by an FFI binding within the Rust code directly, rather than using the FrontendMessage system.
+// Then, this directly calls the `injectImaginatePollServerStatus` function on the `EditorHandle` object which is a JS binding generated by wasm-bindgen, going straight back into the Rust code.
+export function injectImaginatePollServerStatus() {
+	// eslint-disable-next-line @typescript-eslint/no-explicit-any
+	(window as any).editorHandle?.injectImaginatePollServerStatus();
+}