@applitools/eyes-storybook/src/getIframeUrl.js

'use strict';
const {URL} = require('url');

function getIframeUrl(baseUrl) {
  const {origin, pathname, search} = new URL(baseUrl);

  let baseUrlFixed = `${origin}${pathname.replace(/\/[^\/]+\.html/, '')}`;

  if (!/\/$/.test(baseUrlFixed)) {
    baseUrlFixed += '/';
  }

  const url = new URL('iframe.html', baseUrlFixed);
  url.searchParams.set('eyes-storybook', 'true');
  if (search) {
    const origParams = new URLSearchParams(search);
    for (const [k, v] of origParams) {
      if (k === 'path') continue; // skip story selection on initial load
      url.searchParams.set(k, v);
    }
  }
  return url.href;
}

module.exports = getIframeUrl;