cli.ex

defmodule Pince.CLI do
  @moduledoc """
  Usage pince --from path --to path
  """
  def main(argv) do
    argv
    |> parse_args
    |> process
  end

  @doc """
  `argv` can be -h or --help which returns :help and can also be --from or -f which sets where the
  Pince project resides and --to or -t which sets the target path
  """
  def parse_args(argv) do
    parse = OptionParser.parse(argv, switches: [ help: :boolean,
                                                 from: :string ,
                                                 to:   :string ],
                                     aliases:  [ h:    :help,
                                                 f:    :from,
                                                 t:    :to ])
    case parse do
      { [ help: true ], _, _ } -> :help
      { options       , _, _ } -> Keyword.put_new(options, :from, ".")
    end
  end

  @doc """
  Displays a help message.
  """
  def process(:help) do
    IO.puts @moduledoc
    System.halt(0)
  end

  def process(options) do
    Pince.Site.process(options)
  end
end