(function (root, factory) {
  if (typeof module === 'object' && module.exports) module.exports = factory;
  else root.createLoginController = factory;
}(typeof self !== 'undefined' ? self : this, function createLoginController(options) {
  const form = options.form;
  const status = options.status;
  const button = options.button;
  const fetchImpl = options.fetchImpl;
  const location = options.location;
  const setIntervalImpl = options.setIntervalImpl || setInterval;
  const clearIntervalImpl = options.clearIntervalImpl || clearInterval;
  let timer = null;

  function showRetryCountdown(seconds) {
    let remaining = Math.max(1, Number.parseInt(seconds, 10) || 1);
    button.disabled = true;
    status.textContent = `Too many attempts. Try again in ${remaining} seconds.`;
    timer = setIntervalImpl(() => {
      remaining -= 1;
      if (remaining <= 0) {
        clearIntervalImpl(timer);
        timer = null;
        button.disabled = false;
        status.textContent = 'You can try signing in again.';
        return;
      }
      status.textContent = `Too many attempts. Try again in ${remaining} seconds.`;
    }, 1000);
  }

  async function submit(accessToken) {
    status.textContent = 'Signing in…';
    let response;
    try {
      response = await fetchImpl('api/v1/session', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ access_token: accessToken }),
      });
    } catch (_error) {
      form.reset();
      status.textContent = 'Sign-in failed. Check your connection and try again.';
      return;
    }
    form.reset();
    if (response.ok) {
      location.replace('./');
      return;
    }
    if (response.status === 429) {
      showRetryCountdown(response.headers.get('Retry-After'));
      return;
    }
    status.textContent = 'Sign-in failed. Check the token and try again.';
  }

  return { submit };
}));

if (typeof document !== 'undefined') {
  const form = document.getElementById('sign-in');
  const status = document.getElementById('status');
  const button = document.getElementById('submit-sign-in');
  const controller = createLoginController({
    form,
    status,
    button,
    fetchImpl: fetch.bind(window),
    location: window.location,
  });
  form.addEventListener('submit', event => {
    event.preventDefault();
    const accessToken = new FormData(form).get('access_token');
    controller.submit(accessToken);
  });
}