import { useEffect, useState } from 'react';

/**
 * Subscribe to a CSS media query and re-render when it flips.
 * Cheap: one matchMedia listener for the lifetime of the consumer.
 */
export function useMediaQuery(query) {
  const [matches, setMatches] = useState(() =>
    typeof window !== 'undefined' && window.matchMedia
      ? window.matchMedia(query).matches
      : false,
  );

  useEffect(() => {
    if (typeof window === 'undefined' || !window.matchMedia) return;
    const mql = window.matchMedia(query);
    const onChange = (e) => setMatches(e.matches);
    setMatches(mql.matches);
    mql.addEventListener('change', onChange);
    return () => mql.removeEventListener('change', onChange);
  }, [query]);

  return matches;
}