import type { Ref, RefCallback } from 'preact';
import { type MutableRefObject, useCallback } from 'preact/compat';

type PossibleRef<T> = Ref<T> | undefined;

const assignRef = <T>(ref: PossibleRef<T>, value: T) => {
  if (typeof ref === 'function') {
    ref(value);
  } else if (ref !== null) {
    (ref as MutableRefObject<T>).current = value;
  }
};

const mergeRefs = <T>(...refs: PossibleRef<T>[]) => {
  return (node: T) => {
    for (const ref of refs) {
      if (ref) {
        assignRef(ref, node);
      }
    }
  };
};

export const useMergedRefs = <T>(...refs: PossibleRef<T>[]) => {
  return useCallback(mergeRefs(...refs), [...refs]) as RefCallback<T>;
};