multilevel_select

$ ->
  $groups_selector = $('#user_advertisement_company_fb_page_id')
  $fb_accounts_selector = $('#user_advertisement_company_facebook_account_id')
  $stub_message = $('<option/>', text: 'Идет загрузка…')

  group_filler = ->
    if @value
      previous_value = $('option', $groups_selector).val()
      $groups_selector.html $stub_message
      $.getJSON "/api/facebook_accounts/#{@value}/pages", (data) ->
        $groups_selector.empty()
        $.each data, (index, page) ->
          $groups_selector.append $('<option/>', value: page.id, text: page.name)
        $groups_selector.val previous_value
    else
      $groups_selector.empty()

  group_filler.call $fb_accounts_selector[0]
  $fb_accounts_selector.change group_filler