(() => {
  const auth = window.TrafficAuth;
  const $ = (id) => document.getElementById(id);
  const enrollmentByUser = new Map();
  const userSelect = $('loginUser');

  auth.users.forEach((user) => userSelect.add(new Option(`${user.username} · ${user.role === 'admin' ? '管理员' : '普通用户'}`, user.username)));

  function nextPage() {
    const next = new URLSearchParams(location.search).get('next');
    return ['link-generator.html', 'link-history.html'].includes(next) ? next : 'link-generator.html';
  }

  function showToast(message) {
    const toast = $('toast');
    toast.textContent = message; toast.classList.add('show');
    setTimeout(() => toast.classList.remove('show'), 1600);
  }

  function currentEnrollment() {
    const username = userSelect.value;
    if (!enrollmentByUser.has(username)) enrollmentByUser.set(username, auth.createEnrollment(username));
    return enrollmentByUser.get(username);
  }

  function renderMode() {
    const username = userSelect.value;
    const user = auth.findUser(username);
    const enrolled = auth.isEnrolled(username);
    $('selectedRole').innerHTML = `<span class="user-role ${user.role}">${user.role === 'admin' ? '管理员' : '普通用户'}</span><small>${enrolled ? '已在当前浏览器绑定' : '首次使用，需要完成本机设置'}</small>`;
    $('signinForm').classList.toggle('hidden', !enrolled);
    $('enrollForm').classList.toggle('hidden', enrolled);
    $('loginTitle').textContent = enrolled ? '用户登录' : '首次绑定';
    $('loginSubtitle').textContent = enrolled ? '密码和动态验证码双重验证' : '设置密码并绑定 Google Authenticator';
    $('signinMessage').textContent = '';
    $('enrollMessage').textContent = '';
    if (!enrolled) {
      const enrollment = currentEnrollment();
      $('setupKey').textContent = enrollment.secret.match(/.{1,4}/g).join(' ');
      $('authAccountName').textContent = `Traffic Intelligence (${username})`;
    }
  }

  $('signinForm').addEventListener('submit', async (event) => {
    event.preventDefault();
    const button = event.submitter;
    button.disabled = true;
    $('signinMessage').textContent = '正在验证…';
    try {
      await auth.login(userSelect.value, $('signinPassword').value, $('signinCode').value);
      location.href = nextPage();
    } catch (error) {
      $('signinMessage').textContent = error.message;
      button.disabled = false;
    }
  });

  $('enrollForm').addEventListener('submit', async (event) => {
    event.preventDefault();
    const password = $('newPassword').value;
    if (password !== $('confirmPassword').value) {
      $('enrollMessage').textContent = '两次输入的密码不一致';
      return;
    }
    const button = event.submitter;
    button.disabled = true;
    $('enrollMessage').textContent = '正在绑定…';
    try {
      await auth.enroll(userSelect.value, password, currentEnrollment().secret, $('setupCode').value);
      location.href = nextPage();
    } catch (error) {
      $('enrollMessage').textContent = error.message;
      button.disabled = false;
    }
  });

  $('copySetupKey').addEventListener('click', async () => {
    const secret = currentEnrollment().secret;
    try { await navigator.clipboard.writeText(secret); }
    catch (_) {
      const area = document.createElement('textarea'); area.value = secret;
      document.body.appendChild(area); area.select(); document.execCommand('copy'); area.remove();
    }
    showToast('设置密钥已复制');
  });

  $('resetEnrollment').addEventListener('click', () => {
    const username = userSelect.value;
    if (!window.confirm(`确定清除 ${username} 在当前浏览器的密码和 Authenticator 绑定吗？`)) return;
    try {
      auth.clearEnrollment(username);
      enrollmentByUser.delete(username);
      $('signinPassword').value = '';
      $('signinCode').value = '';
      renderMode();
      showToast('本机绑定已清除，请重新设置');
    } catch (error) {
      $('signinMessage').textContent = error.message;
    }
  });

  userSelect.addEventListener('change', renderMode);
  if (auth.currentUser()) location.replace(nextPage());
  else renderMode();
})();