Autocomplete text-field version of dynamic select menu?

I have a form for submission of brand, model, and style. Style
belongs_to model, and model belongs_to brand. The form is actually a
style submission form, but allows users to create new brands or models
as well, should they not exist.

What I want is for the autocomplete for 'model' to populate when an
object for 'brand' is selected in the first text field..

..and so on for submodel...

I have the following autocomplete field for brand

<%= form_for @style, :html => { :class => 'form-horizontal' } do |f| %>
  <fieldset>
    <legend></legend>

    <div class="control-group">
      <%= f.label :brand_name, :class => 'control-label' %>
      <div class="controls">
        <%= f.text_field :brand_name, data: {autocomplete_source:
brands_path}, :class => 'text_field' %>
      </div>
    </div>

    <div class="form-actions">
      <%= f.submit nil, :class => 'btn btn-primary' %>
      <%= link_to 'Cancel', styles_path, :class => 'btn' %>
    </div>
  </fieldset>

<% end %>

and in styles.rb (model):

belongs_to :brand

  def brand_name
    brand.try(:name)
    end

  def brand_name=(name)
    self.brand = Brand.find_or_create_by_name(name) if name.present?
  end

and in styles.js.coffeescript:

jQuery ->
  $('#style_brand_name').autocomplete
    source: $('#style_brand_name').data('autocomplete-source')