refactor(infra): directory structure (#4615)

packages/frontend/electron/src/shared/utils.ts

@@ -0,0 +1,40 @@
+import type { EventBasedChannel } from 'async-call-rpc';
+
+export function getTime() {
+  return new Date().getTime();
+}
+
+export const isMacOS = () => {
+  return process.platform === 'darwin';
+};
+
+export const isWindows = () => {
+  return process.platform === 'win32';
+};
+
+interface MessagePortLike {
+  postMessage: (data: unknown) => void;
+  addListener: (event: 'message', listener: (...args: any[]) => void) => void;
+  removeListener: (
+    event: 'message',
+    listener: (...args: any[]) => void
+  ) => void;
+}
+
+export class MessageEventChannel implements EventBasedChannel {
+  constructor(private worker: MessagePortLike) {}
+
+  on(listener: (data: unknown) => void) {
+    const f = (data: unknown) => {
+      listener(data);
+    };
+    this.worker.addListener('message', f);
+    return () => {
+      this.worker.removeListener('message', f);
+    };
+  }
+
+  send(data: unknown) {
+    this.worker.postMessage(data);
+  }
+}