let branches = [];

async function loadBranches() {
  const res = await fetch(`${API}/api/branches`, { headers: hdr() });
  if (!res.ok) return;
  branches = await res.json();
  renderBranches();
}

function renderBranches() {
  const el = document.getElementById('branchesGrid');
  if (!branches.length) {
    el.innerHTML = '<div class="empty" style="grid-column:1/-1">Филиалов пока нет. Нажмите «Добавить филиал».</div>';
    return;
  }
  el.innerHTML = branches.map(b => `
    <div class="branch-card" data-id="${b.id}">
      <div class="branch-header">
        <span class="branch-name">${esc(b.name)}</span>
        <span class="branch-badge">${b.groups_count} ${plural(b.groups_count, 'группа', 'группы', 'групп')}</span>
      </div>
      ${b.address ? `<div class="branch-meta">📍 ${esc(b.address)}</div>` : ''}
      ${b.phone ? `<div class="branch-meta">📞 ${esc(b.phone)}</div>` : ''}
      <div class="branch-actions">
        <button class="branch-edit" data-edit-branch="${b.id}" title="Редактировать">✎</button>
        ${b.groups_count === 0 ? `<button class="branch-delete" data-del-branch="${b.id}" title="Удалить">&times;</button>` : ''}
      </div>
    </div>
  `).join('');
}

function plural(n, one, few, many) {
  n = Math.abs(n) % 100; const n1 = n % 10;
  if (n > 10 && n < 20) return many;
  if (n1 > 1 && n1 < 5) return few;
  if (n1 === 1) return one;
  return many;
}

function openBranchModal(id = null) {
  const modal = document.getElementById('branchModal');
  const form = document.getElementById('branchForm');
  const title = document.getElementById('branchModalTitle');
  const submitBtn = document.getElementById('branchSubmitBtn');
  form.reset();
  document.getElementById('branchId').value = '';
  if (id) {
    const b = branches.find(x => x.id === id);
    if (!b) return;
    title.textContent = 'Редактировать филиал';
    submitBtn.textContent = 'Сохранить';
    form.name.value = b.name;
    form.address.value = b.address || '';
    form.phone.value = b.phone || '';
    document.getElementById('branchId').value = b.id;
  } else {
    title.textContent = 'Создать филиал';
    submitBtn.textContent = 'Создать';
  }
  modal.classList.add('open');
  setTimeout(() => form.name.focus(), 100);
}

function closeBranchModal() {
  document.getElementById('branchModal').classList.remove('open');
}

document.getElementById('branchForm').addEventListener('submit', async (e) => {
  e.preventDefault();
  const fd = new FormData(e.target);
  const id = fd.get('id');
  const name = fd.get('name').trim();
  const address = fd.get('address').trim();
  const phone = fd.get('phone').trim();
  if (!name) { alert('Название обязательно'); return; }

  const url = id ? `${API}/api/branches/${id}` : `${API}/api/branches`;
  const method = id ? 'PUT' : 'POST';
  const res = await fetch(url, {
    method,
    headers: hdrJson(),
    body: JSON.stringify({ name, address: address || null, phone: phone || null })
  });
  if (res.ok) {
    showToast(id ? 'Филиал обновлён' : 'Филиал создан');
    closeBranchModal();
    loadBranches();
  } else { const err = await res.json(); alert(err.error || 'Ошибка'); }
});

async function deleteBranch(id) {
  if (!confirm('Удалить этот филиал?')) return;
  const res = await fetch(`${API}/api/branches/${id}`, { method: 'DELETE', headers: hdr() });
  if (res.ok) {
    showToast('Филиал удалён');
    loadBranches();
  } else { const err = await res.json(); alert(err.error || 'Ошибка'); }
}

document.getElementById('addBranchBtn').addEventListener('click', () => openBranchModal());
document.getElementById('branchModal').addEventListener('click', e => { if (e.target === e.currentTarget) closeBranchModal(); });
document.getElementById('branchCancelBtn').addEventListener('click', closeBranchModal);
document.getElementById('imgModal').addEventListener('click', e => e.currentTarget.classList.remove('open'));

document.getElementById('branchesGrid').addEventListener('click', e => {
  const ed = e.target.closest('[data-edit-branch]');
  if (ed) { openBranchModal(parseInt(ed.dataset.editBranch, 10)); return; }
  const dl = e.target.closest('[data-del-branch]');
  if (dl) { deleteBranch(parseInt(dl.dataset.delBranch, 10)); }
});

(async () => {
  if (await requireAdminPage()) {
    buildSidebar(document.body.dataset.page);
    loadBranches();
  }
})();