[jquery] sort then group by character

sort_then_group_by_character.coffee

$.sort_then_group_by_character = (sortable, ul_class)->

  $.sort_by_words(ul_class, sortable)

  $('ul.group').empty()

  count = 0
  character = ''

  $("ul.#{ul_class} li").each (index, li_el) ->

    # get attributes
    str = $(li_el).data(sortable).toLowerCase()
    content = $(li_el).html()

    # reset element when letter change
    if character isnt str[0]
      character = null

    # new character, build box
    unless character
      character = str[0]
      $('ul.group').append("<li id='box-#{character}' class='group-item'><div class='outer'><div class='title'>#{character.toUpperCase()}</div><ul class='subgroup'></li>")

    # prepare item
    item = $("<a id='item-#{character}'>#{content}</a>")
    $.each item.data(), (k,v) ->
      item.data(k,$(li_el).data(k))

    # wrap item
    el = $("<li class='subgroup'></li>").append(item)

    # add item
    $("li#box-#{character} ul.subgroup").append(el)