defmodule Mix.Tasks.DbSeeds.Gen.Seed do
  @moduledoc false

  use Mix.Task

  import Mix.Ecto
  import Mix.DbSeeds
  import Mix.Generator

  @shortdoc "Executes the seeds for specified env and tags down"

  def run(args) do
    no_umbrella!("db_seeds.gen.seed")
    repos = parse_repo(args)

    Enum.each(repos, fn repo ->
      case OptionParser.parse(args) do
        {_, [name], _} ->
          ensure_repo(repo, args)
          path = Path.relative_to(seeds_path(repo), Mix.Project.app_path())
          file = Path.join(path, "#{timestamp()}_#{name}.exs")
          create_directory(path)

          create_file(
            file,
            seed_template(
              root_mod: root_mod(repo),
              mod: Module.concat([repo, Seeds, Inflex.camelize(name)])
            )
          )

        {_, _, _} ->
          Mix.raise(
            "expected db_seeds.gen.seed to receive the seed file name, " <>
              "got: #{inspect(Enum.join(args, " "))}"
          )
      end
    end)
  end

  defp timestamp do
    {{y, m, d}, {hh, mm, ss}} = :calendar.universal_time()
    "#{y}#{pad(m)}#{pad(d)}#{pad(hh)}#{pad(mm)}#{pad(ss)}"
  end

  defp pad(i) when i < 10, do: <<?0, ?0 + i>>
  defp pad(i), do: to_string(i)

  embed_template(:seed, """
  defmodule <%= inspect @mod %> do
    use <%= inspect @root_mod %>.Seed

    envs [:dev]

    def up(_repo) do
    end
  end
  """)
end