snapshot of https://github.com/shadcn-ui/ui.git (main, 2026-09-15; blobs > 131072B omitted)

apps/v4/app/(app)/(create)/hooks/use-iframe-sync.tsx

@@ -0,0 +1,69 @@
+"use client"
+
+import * as React from "react"
+
+import type { DesignSystemSearchParams } from "@/app/(app)/(create)/lib/search-params"
+
+type ParentToIframeMessage = {
+  type: "design-system-params"
+  data: DesignSystemSearchParams
+}
+
+export const isInIframe = () => {
+  if (typeof window === "undefined") {
+    return false
+  }
+  return window.self !== window.top
+}
+
+export function useIframeMessageListener<
+  Message extends ParentToIframeMessage,
+  MessageType extends Message["type"],
+>(
+  messageType: MessageType,
+  onMessage: (data: Extract<Message, { type: MessageType }>["data"]) => void
+) {
+  const onMessageRef = React.useRef(onMessage)
+
+  React.useEffect(() => {
+    onMessageRef.current = onMessage
+  }, [onMessage])
+
+  React.useEffect(() => {
+    if (!isInIframe()) {
+      return
+    }
+
+    const handleMessage = (event: MessageEvent) => {
+      if (event.data.type === messageType) {
+        onMessageRef.current(event.data.data)
+      }
+    }
+
+    window.addEventListener("message", handleMessage)
+    return () => {
+      window.removeEventListener("message", handleMessage)
+    }
+  }, [messageType])
+}
+
+export function sendToIframe<
+  Message extends ParentToIframeMessage,
+  MessageType extends Message["type"],
+>(
+  iframe: HTMLIFrameElement | null,
+  messageType: MessageType,
+  data: Extract<Message, { type: MessageType }>["data"]
+) {
+  if (!iframe?.contentWindow) {
+    return
+  }
+
+  iframe.contentWindow.postMessage(
+    {
+      type: messageType,
+      data,
+    },
+    "*"
+  )
+}