Shopify - custom line items with metafields

custom line item metafields

{% if product.metafields.properties.size > 0 %}
<div class="col-xs-12 col-lg-6">
{% for l_item in product.metafields.properties %}
{% assign key = l_item.first | split: ':' %}
{% assign key_type = key.last %}
{% assign key_title = key.first %}
{% assign value = l_item.last %}
<div class="form-group">
  <label>{{ key_title }}</label>
  {% if key_type == 'select' %}
  {% assign value_array = value | split: ',' %}
  <select class="form-control" name="properties[{{ key_title }}]">
  	{% for v in value_array %}
  	<option value="{{ v }}">{{ v }}</option>
  	{% endfor %}
  </select>
  {% elsif key_type == 'text' %}
  <input type="text" class="form-control" name="properties[{{ key_title }}]" placeholder="{{ value }}" />
  {% elsif key_type == 'checkbox' %}
  <p><input type="checkbox" name="properties[{{ key_title }}]" value="{{ value }}" />&nbsp;{{ value }}</p>
  {% elsif key_type == 'file' %}
  <p><input type="file" id="{{ key_title }}" name="properties[{{ key_title }}]">&nbsp;<small><em>{{ value }}</em></small></p>
  {% endif %}
</div>
{% endfor %}
</div>
{% endif %}