// Shared utility helpers
const { useState, useEffect, useRef, useMemo, useCallback } = React;

function smoothScrollTo(id) {
  const el = document.getElementById(id);
  if (!el) return;
  const y = el.getBoundingClientRect().top + window.scrollY - 70;
  window.scrollTo({ top: y, behavior: 'smooth' });
}

function useScrollY() {
  const [y, setY] = useState(0);
  useEffect(() => {
    let raf = 0;
    function onScroll() {
      if (raf) return;
      raf = requestAnimationFrame(() => {
        setY(window.scrollY);
        raf = 0;
      });
    }
    window.addEventListener('scroll', onScroll, { passive: true });
    onScroll();
    return () => window.removeEventListener('scroll', onScroll);
  }, []);
  return y;
}

Object.assign(window, { useState, useEffect, useRef, useMemo, useCallback, smoothScrollTo, useScrollY });