// ============================================================
// Cacyli — Hooks utility
// ============================================================

const useScrollProgress = () => {
  const [progress, setProgress] = React.useState(0);
  React.useEffect(() => {
    const onScroll = () => {
      const h = document.documentElement;
      const max = h.scrollHeight - h.clientHeight;
      setProgress(max > 0 ? h.scrollTop / max : 0);
    };
    window.addEventListener('scroll', onScroll, { passive: true });
    onScroll();
    return () => window.removeEventListener('scroll', onScroll);
  }, []);
  return progress;
};

const useReveal = () => {
  React.useEffect(() => {
    const els = document.querySelectorAll('.reveal');
    if (!('IntersectionObserver' in window)) {
      els.forEach((el) => el.classList.add('is-visible'));
      return;
    }
    const io = new IntersectionObserver(
      (entries) => {
        entries.forEach((e) => {
          if (e.isIntersecting) {
            e.target.classList.add('is-visible');
            io.unobserve(e.target);
          }
        });
      },
      { threshold: 0.12, rootMargin: '0px 0px -60px 0px' }
    );
    els.forEach((el) => io.observe(el));
    return () => io.disconnect();
  }, []);
};

const useCounter = (target, duration = 1600, deps = []) => {
  const [val, setVal] = React.useState(0);
  const ref = React.useRef(null);
  const [trigger, setTrigger] = React.useState(false);

  React.useEffect(() => {
    if (!ref.current) return;
    const io = new IntersectionObserver(
      (entries) => {
        entries.forEach((e) => { if (e.isIntersecting) setTrigger(true); });
      },
      { threshold: 0.4 }
    );
    io.observe(ref.current);
    return () => io.disconnect();
  }, []);

  React.useEffect(() => {
    if (!trigger) return;
    const reduced = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
    if (reduced) { setVal(target); return; }
    let raf;
    const start = performance.now();
    const step = (t) => {
      const p = Math.min(1, (t - start) / duration);
      const eased = 1 - Math.pow(1 - p, 3);
      setVal(target * eased);
      if (p < 1) raf = requestAnimationFrame(step);
    };
    raf = requestAnimationFrame(step);
    return () => cancelAnimationFrame(raf);
  }, [trigger, target, duration]);

  return [val, ref];
};

window.useScrollProgress = useScrollProgress;
window.useReveal = useReveal;
window.useCounter = useCounter;