(function () {
  'use strict';

  const bell = document.querySelector('[data-notification-bell]');
  if (!bell) return;

  const countEl = bell.querySelector('[data-unread-count]');
  const dropdown = bell.querySelector('[data-notification-dropdown]');
  let isOpen = false;

  bell.addEventListener('click', () => {
    isOpen = !isOpen;
    dropdown.hidden = !isOpen;
    if (isOpen) loadNotifications();
  });

  document.addEventListener('click', (e) => {
    if (!bell.contains(e.target)) {
      isOpen = false;
      dropdown.hidden = true;
    }
  });

  async function updateBell() {
    try {
      const res = await fetch('/api/notifications/bell');
      if (!res.ok) return;
      const data = await res.json();
      const count = data.unreadCount || 0;
      countEl.textContent = count > 99 ? '99+' : String(count);
      countEl.hidden = count === 0;
      bell.classList.toggle('has-unread', count > 0);
    } catch (err) {
      console.error('bell update', err);
    }
  }

  async function loadNotifications() {
    try {
      const res = await fetch('/api/notifications?limit=20');
      if (!res.ok) return;
      const data = await res.json();
      renderNotifications(data.notifications || []);
    } catch (err) {
      console.error('load notifications', err);
    }
  }

  function renderNotifications(notifications) {
    const list = dropdown.querySelector('ul');
    if (!list) return;
    list.innerHTML = '';

    if (!notifications.length) {
      list.innerHTML = '<li class="notification-empty">No notifications</li>';
      return;
    }

    notifications.forEach(n => {
      const li = document.createElement('li');
      li.className = n.readAt ? 'notification-item is-read' : 'notification-item';
      li.innerHTML = `
        <div class="notification-message">${escapeHtml(n.message)}</div>
        <time class="notification-time">${formatDate(n.createdAt)}</time>
      `;
      if (!n.readAt) {
        li.addEventListener('click', () => markRead(n.id));
      }
      list.appendChild(li);
    });

    // Add "Mark all read" button
    const footer = document.createElement('li');
    footer.className = 'notification-footer';
    const btn = document.createElement('button');
    btn.textContent = 'Mark all read';
    btn.addEventListener('click', markAllRead);
    footer.appendChild(btn);
    list.appendChild(footer);
  }

  async function markRead(id) {
    try {
      await fetch(`/api/notifications/${id}/read`, { method: 'POST' });
      updateBell();
      loadNotifications();
    } catch (err) {
      console.error('mark read', err);
    }
  }

  async function markAllRead() {
    try {
      await fetch('/api/notifications/read-all', { method: 'POST' });
      updateBell();
      loadNotifications();
    } catch (err) {
      console.error('mark all read', err);
    }
  }

  function escapeHtml(str) {
    const div = document.createElement('div');
    div.textContent = str;
    return div.innerHTML;
  }

  function formatDate(iso) {
    const d = new Date(iso);
    return d.toLocaleString();
  }

  // Listen for WebSocket notification events
  if (window.__cairnquireRealtime) {
    window.__cairnquireRealtime.on('notification', () => {
      updateBell();
    });
  }

  // Poll every 60s as fallback
  setInterval(updateBell, 60000);
  updateBell();
})();