sentinel/static/app/utils/useOnClickOutside.tsx

import {useEffect} from 'react';

// hook from https://usehooks.com/useOnClickOutside/
function useOnClickOutside<T extends HTMLElement = HTMLElement>(
  ref: React.RefObject<T> | T | null,
  handler: (event: MouseEvent | TouchEvent) => void
) {
  useEffect(
    () => {
      const listener = (event: MouseEvent | TouchEvent) => {
        if (!ref) {
          return;
        }
        let el: T | null;
        if ('current' in ref) {
          el = ref.current;
        } else {
          el = ref;
        }

        // Do nothing if clicking ref's element or descendent elements
        if (!el || el.contains(event.target as Node)) {
          return;
        }

        handler(event);
      };

      document.addEventListener('mousedown', listener);
      document.addEventListener('touchstart', listener);
      return () => {
        document.removeEventListener('mousedown', listener);
        document.removeEventListener('touchstart', listener);
      };
    },
    // Reload only if ref or handler changes
    [ref, handler]
  );
}

export default useOnClickOutside;