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| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 | 6x 6x 21x 108x 108x | import { atom, useAtomValue, useSetAtom } from "jotai";
import { atomFamily } from "jotai/utils";
import { useCallback, useEffect } from "react";
import { createPortal } from "react-dom";
 
type PortalName = "aside" | "modal" | "notification";
type PortalMap = Partial<Record<PortalName, HTMLElement>>;
 
const portalsState = atom<PortalMap>({});
const portalElementState = atomFamily((portalName: PortalName) => {
  return atom((get) => get(portalsState)[portalName]);
});
 
/**
 * Returns a ref to be assigned to an element that will serve as a portal render target;
 * the portal can be used by rendering inside a `<PortalEntrance name={name} />`
 */
function usePortalExit(name: PortalName) {
  const setPortals = useSetAtom(portalsState);
 
  const handlePortalRef = useCallback((node: HTMLElement | null) => {
    setPortals((portals) => ({
      ...portals,
      [name]: node,
    }));
  }, []);
 
  useEffect(() => {
    // cleanup function removes the reference to the portal exit element on unmount
    return () => {
      setPortals((portals) => ({
        ...portals,
        [name]: undefined,
      }));
    };
  }, []);
 
  return handlePortalRef;
}
 
function PortalEntrance({
  name,
  children,
}: {
  name: PortalName;
  children?: React.ReactNode;
}) {
  const portalElement = useAtomValue(portalElementState(name));
 
  return (
    <>{children && portalElement && createPortal(children, portalElement)}</>
  );
}
 
export { PortalEntrance, usePortalExit };
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