// Adapted from agentui (https://github.com/ashish200729/agentui) — replaces `useReducedMotion` from motion/react.
// Copyright (c) 2026 Saurabh Chauhan. MIT License, see ./LICENSE-agentui.md
// 改造:不引 motion 库,直接读 prefers-reduced-motion;样式层的减弱动效由 motion-reduce: 变体负责,这里只给 JS 滚动用。
import { useSyncExternalStore } from "react";

const QUERY = "(prefers-reduced-motion: reduce)";

function subscribe(cb: () => void) {
  if (typeof window === "undefined" || !window.matchMedia) return () => {};
  const mq = window.matchMedia(QUERY);
  mq.addEventListener("change", cb);
  return () => mq.removeEventListener("change", cb);
}

export function useReducedMotion(): boolean {
  return useSyncExternalStore(
    subscribe,
    () => (typeof window !== "undefined" && window.matchMedia ? window.matchMedia(QUERY).matches : false),
    () => false,
  );
}