Changes to ui-sortable for compatibility with ConnectWith option.

ui-sortable-connectwith-compatible.coffee

onStart = (e, ui) ->
  # Save position of dragged item, original model, and original element parent
  ui.item.data('ui-sortable-start', ui.item.index())
  ui.item.data('ui-sortable-start-model', ngModel)
  ui.item.data('ui-sortable-start-parent', ui.item.context.parentElement)

onUpdate = (e, ui) ->
  # Fetch saved and current position of dropped element
  start = ui.item.data('ui-sortable-start')
  end   = ui.item.index()

  # Only sort if the original and target parent elements are the same
  startParent = ui.item.data('ui-sortable-start-parent')
  if startParent is ui.item.context.parentElement
    # Reorder array and apply change to scope
    ngModel.$modelValue.splice(end, 0, ngModel.$modelValue.splice(start, 1)[0])

onReceive = (e, ui) ->
  start = ui.item.data('ui-sortable-start')
  end   = ui.item.index()
  startModel = ui.item.data('ui-sortable-start-model')

  # Remove the element from the start array and insert it in this one in the correct order
  ngModel.$modelValue.splice(end, 0, startModel.$modelValue.splice(start, 1)[0])