{% if sourcename and sourcename.endswith('.ipynb') %}
{% set base = sourcename.split('/')[-1] %}        {# e.g. foo.ipynb #}
{% set stem = base[:-6] %}                          {# -> foo #}
{% set binder_url = "https://mybinder.org/v2/gh/"
   ~ github_user ~ "/" ~ github_repo ~ "/" ~ github_version
   ~ "?labpath=" ~ ("docs/source/" ~ sourcename)|urlencode %}
<div class="nb-download-top" style="display:flex; gap:.5rem; align-items:center;">
  <a class="btn btn-sm nb-binder"
     href="{{ binder_url }}"
     target="_blank" rel="noopener">
    <i class="fa-solid fa-rocket"></i> Run in Binder
  </a>
  <!-- .ipynb lives under _sources/<sourcename> in HTML builds -->
  <a class="btn btn-sm nb-ipynb" href="{{ pathto('_sources/' ~ sourcename, 1) }}" download="{{ base }}">
    <i class="fa-solid fa-download"></i> Download .ipynb
  </a>

  <!-- Notebook exports are placed in tutorials_py/ during the Sphinx build -->
  <a class="btn btn-sm nb-py" href="{{ pathto('tutorials_py/' ~ stem ~ '.py', 1) }}" 
     download="{{ stem }}.py">
    <i class="fa-solid fa-code"></i> Download .py
  </a>
</div>

<script>
// Force real download for .ipynb and .py; try a couple of likely locations for .py
(function(){
  function fetchFirst(urls){
    if (!urls.length) return Promise.reject(new Error('no urls'));
    const [u, ...rest] = urls;
    return fetch(u, {credentials: 'same-origin'})
      .then(r => { if(!r.ok) throw new Error('HTTP '+r.status); return r.blob().then(b=>({blob:b, url:u})); })
      .catch(() => fetchFirst(rest));
  }
  function forceDownload(a){
    const alt1 = a.getAttribute('data-alt1');
    const alt2 = a.getAttribute('data-alt2');
    const urls = [a.href].concat(alt1? [alt1]: []).concat(alt2? [alt2]: []);
    fetchFirst(urls).then(({blob}) => {
      const url = URL.createObjectURL(blob);
      const link = document.createElement('a');
      link.href = url;
      link.download = a.getAttribute('download') || (a.href.split('/').pop() || 'download');
      document.body.appendChild(link);
      link.click();
      link.remove();
      URL.revokeObjectURL(url);
    }).catch(err => {
      console.warn('Download fallback to navigation:', err);
      window.location.href = a.href;
    });
  }
  document.addEventListener('click', function(ev){
    var a = ev.target.closest && ev.target.closest('a.nb-ipynb, a.nb-py');
    if (!a) return;
    ev.preventDefault();
    forceDownload(a);
  });
})();
</script>
{% endif %}