partial for adding additional images

gistfile1.rhtml

<div class='image'>
  <% new_or_existing = image.new_record? ? 'new' : 'existing' %>
  <% prefix = "work[#{new_or_existing}_image_attributes][]"%>
  
  <% fields_for prefix, image do |f| %>
    <p>
      <%= f.label :caption %><br />
      <%= f.text_field :caption %>
    </p>  
    <p>
      <% if new_or_existing == 'existing' %>
        <%= image_tag(image.file.url(:thumb, false)) %><br /><br />
        Replace: <%= f.file_field :file %>
        <%= link_to_function "remove", "$(this).parent().parent().remove()"%>
      <% else %>
      File: <%= f.file_field :file %>
      <%= link_to_function "remove", "$(this).parent().parent().remove()"%>
      <% end %>
      <hr style="width: 50%" />
    </p>
  <% end -%>
</div>