popagent

Latest change 6edc7e928c57dab23c0973ed3f7ee70b3ebb72d5 - Initial popagent baseline by AkurAI Build

import { useEffect, type RefObject } from "react";

const FOCUSABLE = 'a[href], button:not([disabled]), textarea, input, select, [tabindex]:not([tabindex="-1"])';

/** Trap Tab focus inside `ref` while `active`; restore focus to the prior element on release. */
export function useFocusTrap(ref: RefObject<HTMLElement | null>, active: boolean): void {
  useEffect(() => {
    if (!active) return;
    const container = ref.current;
    if (!container) return;
    const previous = document.activeElement as HTMLElement | null;
    const trap = (event: KeyboardEvent) => {
      if (event.key !== "Tab") return;
      const focusable = Array.from(container.querySelectorAll<HTMLElement>(FOCUSABLE))
        .filter((element) => element.offsetParent !== null || element === document.activeElement);
      if (!focusable.length) return;
      const first = focusable[0]!;
      const last = focusable[focusable.length - 1]!;
      if (event.shiftKey && document.activeElement === first) {
        event.preventDefault();
        last.focus();
      } else if (!event.shiftKey && document.activeElement === last) {
        event.preventDefault();
        first.focus();
      }
    };
    document.addEventListener("keydown", trap);
    return () => {
      document.removeEventListener("keydown", trap);
      previous?.focus?.();
    };
  }, [ref, active]);
}