(function () {
  const baseLink = 'backredirect/index.html';

  function buildTargetUrl(base) {
    const trimmed = base.trim();
    const query = document.location.search.replace('?', '').toString();
    if (!query) return trimmed;
    const sep = trimmed.indexOf('?') > 0 ? '&' : '?';
    return trimmed + sep + query;
  }

  function setBackRedirect(url) {
    const target = buildTargetUrl(url);

    history.pushState({}, '', location.href);
    history.pushState({}, '', location.href);
    history.pushState({}, '', location.href);

    window.addEventListener('popstate', () => {
      console.log('onpopstate', target);
      setTimeout(() => {
        location.href = target;
      }, 1);
    });
  }

  setBackRedirect(baseLink);
})();