defmodule Mix.Tasks.Rivet.Commit do
  use Mix.Task
  import Mix.Ecto
  import Rivet.Mix.Common

  # "Manage Rivet migrations"
  @shortdoc "Commit pending Rivet Model Migrations"

  @moduledoc @shortdoc

  @switches [
    # all: :boolean,
    #    step: :integer,
    #    to: :integer,
    #    to_exclusive: :integer,
    quiet: :boolean,
    prefix: :string,
    pool_size: :integer,
    log_sql: :boolean,
    log_migrations_sql: :boolean,
    log_migrator_sql: :boolean,
    strict_version_order: :boolean,
    repo: [:keep, :string],
    no_compile: :boolean,
    no_deps_check: :boolean
    #    migrations_path: :keep
  ]

  @defaults [
    all: true,
    log: false,
    log_migrations_sql: false,
    log_migrator_sql: false
  ]

  @doc """
  Notes/Options:

  1. call at the top level Mix.Tasks.Ecto.Migrate.run(), with a different
     Migrator as the second argument:

      https://github.com/elixir-ecto/ecto_sql/blob/v3.9.2/lib/mix/tasks/ecto.migrate.ex#L111

  2. clone the run command above and adjust it to suite (taking this option
     for now)

  """

  @impl true
  # a clone of https://github.com/elixir-ecto/ecto_sql/blob/v3.9.2/lib/mix/tasks/ecto.migrate.ex#L111
  def run(args) do
    migrator = &Ecto.Migrator.run/4
    # brittle for now
    {:ok, cfg, _, migs} = get_migrations(args)
    IO.inspect(cfg)
    repos = parse_repo(args)
    {opts, _} = OptionParser.parse!(args, strict: @switches, aliases: [])

    opts = Keyword.merge(@defaults, opts)

    {:ok, _} = Application.ensure_all_started(:ecto_sql)

    for repo <- repos do
      ensure_repo(repo, args)
      pool = repo.config[:pool]

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

      case Ecto.Migrator.with_repo(repo, fun, [mode: :temporary] ++ opts) do
        {:ok, _migrated, _apps} ->
          :ok

        {:error, error} ->
          Mix.raise("Could not start repo #{inspect(repo)}, error: #{inspect(error)}")
      end
    end

    :ok
  end

  defp get_migrations(opts) do
    with {:ok, cfg, opts} <- option_configs(opts),
         {:ok, migs} <- Rivet.Mix.Migration.migrations(cfg, opts) do
      {:ok, cfg, opts,
       Enum.map(migs, fn %{module: mod, index: ver, path: path} ->
         Code.require_file(path)

         if Code.ensure_loaded?(mod) and function_exported?(mod, :__migration__, 0) do
           {ver, mod}
         else
           raise Ecto.MigrationError, "Module #{mod} in #{path} does not define an Ecto.Migration"
         end
       end)}
    end
  end
end