defmodule Mix.Tasks.ExOkf.Format do
  @shortdoc "Rewrite an OKF bundle with normalized frontmatter"
  @moduledoc """
  Loads a bundle and writes it back with normalized YAML frontmatter.

      mix ex_okf.format path/to/bundle
      mix ex_okf.format path/to/bundle --out path/to/normalized
  """

  use Mix.Task

  @impl Mix.Task
  def run(args) do
    {opts, paths, _} = OptionParser.parse(args, strict: [out: :string])
    path = List.first(paths) || Mix.raise("Usage: mix ex_okf.format PATH [--out DEST]")
    dest = opts[:out] || path

    {:ok, bundle} = ExOKF.load(path)
    {status, diags} = ExOKF.validate(bundle)

    if status == :error do
      Mix.shell().error(ExOKF.Diagnostics.format(diags))
      Mix.raise("Refusing to format a non-conformant bundle")
    end

    :ok = ExOKF.write(bundle, dest)
    Mix.shell().info("Wrote normalized bundle to #{dest}")
    :ok
  end
end