// Cache static selectors outside loop/event scope
const $listContainer = $('#product-list');
const $searchInput = $('#search-box');

// Debounce helper to prevent excessive DOM filtering
function debounce(fn, delay = 250) {
  let timer;
  return function(...args) {
    clearTimeout(timer);
    timer = setTimeout(() => fn.apply(this, args), delay);
  };
}

// Attach single delegated handler for all current and future item clicks
$listContainer.on('click', '.product-item', function(e) {
  e.preventDefault();
  const $item = $(this);
  const productId = $item.data('id');
  
  $item.toggleClass('selected');
  console.log('Selected product:', productId);
});

// Debounced live search
$searchInput.on('input', debounce(function() {
  const query = $(this).val().toLowerCase().trim();
  
  $listContainer.children('.product-item').each(function() {
    const text = $(this).text().toLowerCase();
    $(this).toggle(text.indexOf(query) !== -1);
  });
}, 200));

async function fetchUserData(userId) {
  const $status = $('#status-indicator');
  $status.text('Loading profile...').show();

  try {
    // jQuery 3+ $.ajax returns a Promises/A+ compatible Promise
    const data = await $.ajax({
      url: `/api/users/${userId}`,
      method: 'GET',
      dataType: 'json',
      timeout: 5000
    });

    $('#user-name').text(data.name);
    $('#user-email').text(data.email);
    $status.text('Loaded successfully!').delay(2000).fadeOut();
  } catch (xhr) {
    const errorMsg = xhr.responseJSON?.message || xhr.statusText || 'Network failure';
    $status.text(`Error: ${errorMsg}`).addClass('text-danger');
  }
}