import { useEffect, useState } from 'react';

/**
 * The bytes as an object URL that lives as long as the component.
 * @param {Uint8Array|null|undefined} bytes
 * @param {string} mediaType
 * @returns {string} '' until the URL exists
 */
export function useObjectUrl(bytes, mediaType) {
  const [url, setUrl] = useState('');
  useEffect(() => {
    if (!bytes) return undefined;
    const next = URL.createObjectURL(
      new Blob([/** @type {BlobPart} */ (bytes)], { type: mediaType }),
    );
    setUrl(next);
    return () => URL.revokeObjectURL(next);
  }, [bytes, mediaType]);
  return url;
}