// Copyright: © 2026 TWWIM UG. All rights reserved. (www.twwim.com)
/**
 * Visibility-aware refetch toggle for TanStack Query polls.
 * Pauses polling when the tab is hidden; triggers an immediate refetch
 * when it becomes visible again so the operator catches up to the latest
 * messages without waiting for the next poll cadence.
 */

import { useEffect, useState } from 'react';

export function useVisibilityRefetch(onVisible?: () => void) {
  const [isVisible, setIsVisible] = useState<boolean>(
    typeof document !== 'undefined' ? document.visibilityState === 'visible' : true,
  );

  useEffect(() => {
    if (typeof document === 'undefined') return;
    const handler = () => {
      const visible = document.visibilityState === 'visible';
      setIsVisible(visible);
      if (visible && onVisible) onVisible();
    };
    document.addEventListener('visibilitychange', handler);
    return () => document.removeEventListener('visibilitychange', handler);
  }, [onVisible]);

  return isVisible;
}