[Init] Initial commit - NetMesh terminal manager

application/state/windowInputFocus.ts

@@ -0,0 +1,57 @@
+import { netcattyBridge } from "../../infrastructure/services/netcattyBridge";
+
+export const requestWindowInputFocus = (): void => {
+  try {
+    const result = netcattyBridge.get()?.windowFocus?.();
+    void result?.catch?.(() => undefined);
+  } catch {
+    // Browser preview or a disposed Electron bridge.
+  }
+};
+
+export type ScheduledWindowInputFocus = {
+  cancel: () => void;
+};
+
+export const scheduleWindowInputFocus = (): ScheduledWindowInputFocus => {
+  let cancelled = false;
+  let frameId: number | undefined;
+  let timeoutId: ReturnType<typeof setTimeout> | undefined;
+
+  const cancel = () => {
+    cancelled = true;
+    if (frameId !== undefined && typeof cancelAnimationFrame === "function") {
+      cancelAnimationFrame(frameId);
+      frameId = undefined;
+    }
+    if (timeoutId !== undefined) {
+      clearTimeout(timeoutId);
+      timeoutId = undefined;
+    }
+  };
+
+  const runIfVisible = () => {
+    if (cancelled || document.visibilityState !== "visible") return;
+    requestWindowInputFocus();
+  };
+
+  const scheduleFrame: (callback: FrameRequestCallback) => number =
+    typeof requestAnimationFrame === "function"
+      ? requestAnimationFrame
+      : (callback) => {
+        callback(0);
+        return 0;
+      };
+
+  frameId = scheduleFrame(() => {
+    frameId = undefined;
+    runIfVisible();
+    if (cancelled) return;
+    timeoutId = setTimeout(() => {
+      timeoutId = undefined;
+      runIfVisible();
+    }, 50);
+  });
+
+  return { cancel };
+};