{% set category = product ? product.categories[0] : null %}

<ul class="breadcrumb list-inline">
  <li><a href="{{ site_url('/') }}">Home</a></li>
  <li><a href="{{ site_url('/shop') }}">Shop</a></li>
  {% if category %}
    {% for parent in category.listAllParents() %}
      <li><a href="/category/{{ parent.fullUrlName }}">{{ parent.name }}</a></li>
    {% endfor %}
    <li><a href="/category/{{ category.fullUrlName }}">{{ category.name }}</a></li>
  {% endif %}
  
  {% if product %}
    <li class="active"><a href="{{ '/product/' ~ product.url_name }}">{{ product.name }}</a></li>
  {% endif %}
</ul>