const PAGE_SIZE = 25;

let nfItems = [];
let nfTotal = 0;
let nfUnread = 0;
let nfUnreadOnly = false;
let nfLoading = false;


async function nfMarkRead(id) {
  const res = await fetch(`${API}/api/notifications/${id}/read`, { method: 'POST', headers: hdr() });
  if (!res.ok) { showToast('Не удалось отметить уведомление'); return; }
  const item = nfItems.find(n => n.id === id);
  if (item) item.read = true;
  nfUnread = Math.max(0, nfUnread - 1);
  if (typeof notifyList !== 'undefined') {
    const shared = notifyList.find(n => n.id === id);
    if (shared) shared.read = true;
  }
  if (nfUnreadOnly) {
    nfItems = nfItems.filter(n => n.id !== id);
    nfTotal = Math.max(0, nfTotal - 1);
    loadNotifyPage(true);
    return;
  }
  renderNotifyPage();
  if (typeof setNotifyUnread === 'function') setNotifyUnread(nfUnread);
}

async function nfDelete(id) {
  if (!confirm('Удалить уведомление у всех пользователей?')) return;
  const res = await fetch(`${API}/api/notifications/${id}`, { method: 'DELETE', headers: hdr() });
  if (!res.ok) { showToast('Не удалось удалить уведомление'); return; }
  if (typeof notifyList !== 'undefined') notifyList = notifyList.filter(n => n.id !== id);
  loadNotifyPage(true);
}

async function nfMarkAllRead() {
  const res = await fetch(`${API}/api/notifications/read-all`, { method: 'POST', headers: hdr() });
  if (!res.ok) { showToast('Не удалось отметить уведомления'); return; }
  showToast('Все уведомления прочитаны');
  if (typeof notifyList !== 'undefined') notifyList.forEach(n => { n.read = true; });
  if (typeof setNotifyUnread === 'function') setNotifyUnread(0);
  loadNotifyPage(true);
}

async function nfClearAll() {
  if (!confirm('Удалить все уведомления у всех пользователей? Действие необратимо.')) return;
  const res = await fetch(`${API}/api/notifications`, { method: 'DELETE', headers: hdr() });
  if (!res.ok) { showToast('Не удалось очистить уведомления'); return; }
  const data = await res.json().catch(() => ({}));
  showToast(`Удалено уведомлений: ${data.deleted || 0}`);
  if (typeof notifyList !== 'undefined') notifyList = [];
  if (typeof setNotifyUnread === 'function') setNotifyUnread(0);
  loadNotifyPage(true);
}

function onNotificationArrived() {
  loadNotifyPage(true);
}

function onNotifyListChanged() {
  loadNotifyPage(true);
}

document.getElementById('nfList').addEventListener('click', e => {
  const readBtn = e.target.closest('[data-nf-read]');
  if (readBtn) { e.preventDefault(); nfMarkRead(parseInt(readBtn.dataset.nfRead, 10)); return; }
  const delBtn = e.target.closest('[data-nf-del]');
  if (delBtn) { e.preventDefault(); nfDelete(parseInt(delBtn.dataset.nfDel, 10)); return; }
  if (e.target.closest('a[href]')) {
    const card = e.target.closest('[data-nf-card]');
    if (card) nfMarkRead(parseInt(card.dataset.nfCard, 10));
  }
});

document.getElementById('notifyFilter').addEventListener('click', e => {
  const btn = e.target.closest('button[data-filter]');
  if (!btn) return;
  nfUnreadOnly = btn.dataset.filter === 'unread';
  document.querySelectorAll('#notifyFilter button').forEach(b => b.classList.toggle('active', b === btn));
  loadNotifyPage(true);
});

document.getElementById('nfReadAllBtn').addEventListener('click', nfMarkAllRead);
document.getElementById('nfClearBtn').addEventListener('click', nfClearAll);
document.getElementById('nfMoreBtn').addEventListener('click', () => loadNotifyPage(false));
document.getElementById('nfReloadBtn').addEventListener('click', () => loadNotifyPage(true));

(async () => {
  if (!(await requireAdminPage())) return;
  buildSidebar(document.body.dataset.page);
  const clearBtn = document.getElementById('nfClearBtn');
  if (clearBtn) clearBtn.hidden = !isAdmin();
  const authStatus = document.getElementById('authStatus');
  if (authStatus) authStatus.classList.add('loaded');
  await loadNotifyPage(true);
})();

function nfIcon(type) {
  return typeof NOTIFY_ICONS !== 'undefined' && NOTIFY_ICONS[type] ? NOTIFY_ICONS[type] : 'bell';
}

function nfLevelClass(level) {
  return level === 'warning' || level === 'critical' ? ` level-${level}` : '';
}

function nfCardHtml(n) {
  const when = typeof notifyTime === 'function' ? notifyTime(n.created_at) : '';
  const linkAttr = typeof attrEsc === 'function' ? attrEsc(n.link) : esc(n.link);
  return `<div class="notify-card${n.read ? '' : ' unread'}${nfLevelClass(n.level)}" data-nf-card="${n.id}">
    <span class="notify-ic"><i data-lucide="${nfIcon(n.type)}"></i></span>
    <span class="notify-body">
      <span class="notify-title">${esc(n.title)}</span>
      ${n.body ? `<span class="notify-text">${esc(n.body)}</span>` : ''}
      <span class="notify-time">${esc(when)}${n.read ? '' : ' · не прочитано'}</span>
    </span>
    <span class="notify-card-actions">
      ${n.link ? `<a class="btn-primary ghost" style="padding:6px 12px;font-size:.78rem" href="${linkAttr}">Открыть</a>` : ''}
      ${n.read ? '' : `<button type="button" class="notify-link" data-nf-read="${n.id}">Прочитано</button>`}
      ${isAdmin() ? `<button type="button" class="notify-link" style="color:#ef4444" data-nf-del="${n.id}">Удалить</button>` : ''}
    </span>
  </div>`;
}

function renderNotifyPage() {
  const list = document.getElementById('nfList');
  const state = document.getElementById('nfState');
  const more = document.getElementById('nfMoreBtn');
  if (!list) return;
  list.innerHTML = nfItems.length
    ? nfItems.map(nfCardHtml).join('')
    : `<div class="notify-empty">${nfUnreadOnly ? 'Непрочитанных уведомлений нет' : 'Уведомлений пока нет'}</div>`;
  if (state) {
    state.textContent = nfItems.length
      ? `Показано ${nfItems.length} из ${nfTotal} · непрочитанных: ${nfUnread}`
      : `Непрочитанных: ${nfUnread}`;
  }
  if (more) more.hidden = nfItems.length >= nfTotal;
  renderIcons();
}

async function loadNotifyPage(reset) {
  if (nfLoading) return;
  nfLoading = true;
  const offset = reset ? 0 : nfItems.length;
  try {
    const q = new URLSearchParams({ limit: String(PAGE_SIZE), offset: String(offset) });
    if (nfUnreadOnly) q.set('unread', '1');
    const res = await fetch(`${API}/api/notifications?${q.toString()}`, { headers: hdr() });
    if (!res.ok) { showToast('Ошибка загрузки уведомлений'); return; }
    const data = await res.json();
    const items = data.items || [];
    nfItems = reset ? items : nfItems.concat(items);
    nfTotal = Number(data.total) || 0;
    nfUnread = Number(data.unread) || 0;
    renderNotifyPage();
    if (typeof setNotifyUnread === 'function') setNotifyUnread(nfUnread);
  } catch {
    showToast('Ошибка сети');
  } finally {
    nfLoading = false;
  }
}