phil_columns

defmodule Mix.Tasks.PhilColumns.Rollback do

  use Mix.Task

  import Mix.Ecto
  import Mix.PhilColumns

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

  def run(args, seeder \\ &PhilColumns.Seeder.run/4) do
    repos = parse_repo(args)
            |> List.wrap()

    {opts, _, _} = OptionParser.parse args,
                     switches: [all: :boolean, step: :integer, to: :integer, quiet: :boolean,
                                pool_size: :integer, env: :string],
                     aliases: [e: :env, n: :steps, v: :to]

    opts =
      if opts[:to] || opts[:step] || opts[:all],
        do: opts,
        else: Keyword.put(opts, :all, true)

    opts =
      if opts[:log],
        do: opts,
        else: Keyword.put(opts, :log, :info)

    opts =
      if opts[:quiet],
        do: Keyword.put(opts, :log, false),
        else: opts

    opts =
      if opts[:env],
        do: Keyword.put(opts, :env, String.to_atom(opts[:env])),
        else: Keyword.put(opts, :env, :dev)

    # Start ecto_sql explicitly before as we don't need
    # to restart those apps if migrated.
    {:ok, _} = Application.ensure_all_started(:ecto_sql)

    for repo <- repos do
      ensure_repo(repo, args)
      path = ensure_seeds_path(repo, opts)

      pool = repo.config[:pool]

      fun =
        if Code.ensure_loaded?(pool) and function_exported?(pool, :unboxed_run, 2) do
          &pool.unboxed_run(&1, fn -> seeder.(&1, path, :down, opts) end)
        else
          &seeder.(&1, path, :down, opts)
        end

      case PhilColumns.Seeder.with_repo(repo, fun, [mode: :temporary] ++ opts) do
        {:ok, migrated, apps} -> restart_apps_if_migrated(apps, migrated)
        {:error, error} -> Mix.raise "Could not start repo #{inspect repo}, error: #{inspect error}"
      end
    end
  end

end