defmodule PhxAdmin.EctoFormMappers do
  def checkboxes_to_ids(params) do
    cond do
      params == [""] -> []
      true -> filter_checkboxes(params)
    end
  end

  defp filter_checkboxes(params) do
    # convert to array of id's
    Enum.filter_map(params,
      fn(x) ->
          elem(x, 1) == "on"
      end,
      fn
        {item, _} when is_atom(item) -> Atom.to_string item
        {item, _} -> item
      end
    )
  end
end