/**
 * Compress JSON.stringify with gzip
 */
export async function stringifyCompressed<T>(chords: T): Promise<Blob> {
  const stream = new Blob([JSON.stringify(chords)])
    .stream()
    .pipeThrough(new CompressionStream("gzip"));
  return await new Response(stream).blob();
}

/**
 * Decompress JSON.parse with gzip
 */
export async function parseCompressed<T>(blob: Blob): Promise<T> {
  const stream = blob.stream().pipeThrough(new DecompressionStream("deflate"));
  return await new Response(stream).json();
}

/**
 * Share JS object as url query param
 */
export async function getSharableUrl(
  name: string,
  data: any,
  baseHref = window.location.href,
): Promise<URL> {
  return new Promise(async (resolve) => {
    const reader = new FileReader();
    reader.onloadend = function () {
      const base64String = (reader.result as string).replace(
        /^data:application\/octet-stream;base64,/,
        "",
      );
      const url = new URL(baseHref);
      url.searchParams.set(name, base64String);
      resolve(url);
    };
    reader.readAsDataURL(await stringifyCompressed(data));
  });
}

export async function parseSharableUrl<T>(
  name: string,
  url: string = window.location.href,
): Promise<T | undefined> {
  const searchParams = new URL(url).searchParams;
  if (!searchParams.has(name)) return;

  return await fetch(
    `data:application/octet-stream;base64,${searchParams.get(name)}`,
  )
    .then((it) => it.blob())
    .then((it) => parseCompressed(it));
}