(() => {
  const form = document.getElementById('private-download-form');
  const message = document.getElementById('private-download-message');
  const results = document.getElementById('private-download-results');
  let token = '';

  const download = async (item, button) => {
    button.disabled = true;
    message.textContent = 'Downloading…';
    try {
      const response = await fetch(item.download_path, {
        headers: {'Authorization': 'Bearer ' + token},
      });
      if (!response.ok) throw new Error(response.status === 401 ? 'unauthorized' : 'download');
      const blob = await response.blob();
      const url = URL.createObjectURL(blob);
      const link = document.createElement('a');
      link.href = url;
      link.download = item.file_name;
      document.body.appendChild(link);
      link.click();
      link.remove();
      setTimeout(() => URL.revokeObjectURL(url), 30000);
      message.textContent = 'Download complete.';
    } catch (error) {
      message.textContent = error.message === 'unauthorized'
        ? 'The delivery token is invalid or expired.'
        : 'The download could not be completed.';
    } finally {
      button.disabled = false;
    }
  };

  const render = (items) => {
    results.replaceChildren();
    items.forEach((item) => {
      const card = document.createElement('article');
      card.className = 'panel release-card';
      const target = document.createElement('p');
      target.className = 'eyebrow';
      target.textContent = [item.operating_system, item.architecture, item.linux_abi]
        .filter(Boolean).join(' · ');
      const title = document.createElement('h2');
      title.textContent = item.product_name + ' ' + item.version;
      const detail = document.createElement('p');
      detail.textContent = item.channel_name + ' · ' + item.format + ' · ' + item.file_name;
      const button = document.createElement('button');
      button.type = 'button';
      button.textContent = 'Download';
      button.addEventListener('click', () => download(item, button));
      card.append(target, title, detail, button);
      results.appendChild(card);
    });
  };

  form.addEventListener('submit', async (event) => {
    event.preventDefault();
    const product = document.getElementById('private-product').value.trim();
    const channel = document.getElementById('private-channel').value.trim();
    token = document.getElementById('delivery-token').value.trim();
    results.replaceChildren();
    message.textContent = 'Opening channel…';
    try {
      const response = await fetch(
        '/api/public/v1/products/' + encodeURIComponent(product) +
        '/channels/' + encodeURIComponent(channel) + '/downloads',
        {headers: {'Authorization': 'Bearer ' + token}},
      );
      if (!response.ok) {
        message.textContent = response.status === 401
          ? 'The delivery token is invalid or expired.'
          : 'The private channel was not found.';
        return;
      }
      const payload = await response.json();
      render(payload.items || []);
      message.textContent = payload.items && payload.items.length
        ? 'Private channel opened.'
        : 'This channel has no published artifacts.';
    } catch (_) {
      message.textContent = 'Could not reach the server.';
    }
  });
})();