let onScroll = null;

export function init() {
    const bar = document.querySelector('.site-progress');
    const nav = document.getElementById('site-nav');

    onScroll = () => {
        const max = document.documentElement.scrollHeight - window.innerHeight;
        const p = max > 0 ? window.scrollY / max : 1;

        if (bar) bar.style.transform = `scaleX(${p})`;
        nav?.classList.toggle('scrolled', window.scrollY > 8);
    };

    window.addEventListener('scroll', onScroll, { passive: true });
    onScroll();
}

export function destroy() {
    if (onScroll) window.removeEventListener('scroll', onScroll);
    onScroll = null;
}