[jquery] group by word

group_by_word.coffee

$.group_by_word = (ul_class, sortable, sub_string_count=0)->

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

  count = 0
  word = ''

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

    # get attributes
    str = if sub_string_count is 0 then $(li_el).data(sortable) else $(li_el).data(sortable).toString().substring(0,sub_string_count)
    content = $(li_el).html()

    # reset element when letter change
    if word isnt str
      word = null

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

    # prepare item
    item = $("<a id='item-#{count}'>#{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-#{count} ul.subgroup").append(el)