defmodule Mix.Tasks.Boruta.Gen.Migration do
  @moduledoc """
  Migration task for Boruta.

  Creates `oauth_clients`, `oauth_scopes` and `oauth_tokens` tables.

  > __Note__: This task will create migration files to keep your integration up to date by checking migration file and module names to create missing ones.
  > Thus it is not recommended to change naming since it will recreate the migration in further runs.

  ## Usage statistics gathering
  This task will trigger a REPL to gather statistical info from your usage of the library. The owners are thankful to you for providing those informations since it helps better maintain the product.

  ## Examples
  ```
  mix boruta.gen.migration
  ```
  """

  use Mix.Task

  import Mix.Generator
  import Mix.Ecto
  import Mix.EctoSQL

  @shortdoc "Generates Boruta migrations"

  @doc false
  def run(args) do
    no_umbrella!("boruta.gen.migration")
    repos = parse_repo(args)

    register_application(repos)

    Enum.map(repos, fn repo ->
      ensure_repo(repo, args)

      {:ok, migration_paths} =
        :code.priv_dir(:boruta)
        |> Path.join("boruta/migrations")
        |> File.ls()

      migration_paths
      |> Enum.sort()
      |> Enum.with_index()
      |> Enum.map(&create_migration_file(repo, &1))
    end)
  end

  defp create_migration_file(repo, {original_path, index}) do
    filename = Path.basename(original_path, ".ex")
    [_filename, basename] = Regex.run(~r/\d{14}_(.+)/, filename)

    migration_name = Macro.camelize(basename)
    timestamp = DateTime.utc_now() |> DateTime.add(index) |> Calendar.strftime("%Y%m%d%H%M%S")

    path = Path.join(source_repo_priv(repo), "migrations")
    file = Path.join(path, "#{timestamp}_#{basename}.exs")

    assigns = [
      mod: Module.concat([repo, Migrations, migration_name]),
      migration_name: migration_name
    ]

    fuzzy_path = Path.join(path, "*_#{basename}.exs")

    if Enum.empty?(Path.wildcard(fuzzy_path)) do
      create_file(file, migration_template(assigns))
    end
  end

  defp migration_module do
    case Application.get_env(:ecto_sql, :migration_module, Ecto.Migration) do
      migration_module when is_atom(migration_module) -> migration_module
      other -> Mix.raise("Expected :migration_module to be a module, got: #{inspect(other)}")
    end
  end

  embed_template(:migration, """
  defmodule <%= inspect @mod %> do
    use <%= inspect migration_module() %>

    use Boruta.Migrations.<%= @migration_name %>
  end
  """)

  defp register_application(repos) do
    initialized? =
      Enum.any?(repos, fn repo ->
        try do
          Ecto.Adapters.SQL.query!(repo, "SELECT count(*) FROM oauth_clients")
          true
        rescue
          _ ->
            false
        end
      end)

    unless initialized? do
      register_application_repl()
    end
  end

  @dialyzer {:no_return, register_application_repl: 0}
  defp register_application_repl do
    Finch.start_link(name: RegistrationHttp)
    Application.ensure_started(:telemetry)

    IO.puts("====================")
    IO.puts("Please provide information about boruta package usage for statistical purposes")
    IO.puts("")
    IO.puts("The owners would be thankful if you could provide those information")
    IO.puts("====================")
    company_name = Owl.IO.input(label: "Your company name:", optional: true)
    company_size = Owl.IO.input(label: "Company size:", cast: :integer, optional: true)
    purpose = Owl.IO.input(label: "Purpose of the installation:", optional: true)

    Finch.build(
      :post,
      "https://getform.io/f/f3907bc0-8ae5-46d6-b1ec-9e4253e2e4f1",
      [{"Content-Type", "application/json"}],
      %{
        company_name: company_name,
        company_size: company_size,
        purpose: purpose
      } |> Jason.encode!()
    ) |> Finch.request(RegistrationHttp)
  end
end