# SPDX-FileCopyrightText: 2019 ash contributors <https://github.com/ash-project/ash/graphs/contributors>
#
# SPDX-License-Identifier: MIT

defmodule Ash.Flags do
  @moduledoc false

  @flags []

  @flag_values Enum.reduce(@flags, %{}, fn {key, default}, values ->
                 Map.put(values, key, Keyword.get(@flag_config, key, default))
               end)

  @noop {:__block__, [], []}

  @doc """
  Ensure that the feature flag is set to the expected value, otherwise an
  exception will be thrown at run time.
  """
  @spec assert!(atom, any) :: Macro.t()
  defmacro assert!(_flag, _expected) when @flag_values == %{}, do: @noop

  # defmacro assert!(flag, expected) when :erlang.map_get(flag, @flag_values) == expected, do: @noop

  # defmacro assert!(flag, expected) when :erlang.map_get(flag, @flag_values) != expected do
  #   actual = Map.get(@flag_values, flag)

  #   heading =
  #     "Expected value of the `#{inspect(flag)}` feature flag to be `#{inspect(expected)}`,
  #   however it is `#{inspect(actual)}`."

  #   quote do
  #     raise Ash.Error.Framework.FlagAssertionFailed.exception(
  #             flag: unquote(flag),
  #             heading: unquote(heading)
  #           )
  #   end
  # end

  @doc """
  Ensure that the feature flag is set to the expected value, otherwise an
  exception will be thrown at run time.
  """
  @spec refute!(atom, any) :: Macro.t()
  defmacro refute!(_flag, _expected) when @flag_values == %{}, do: @noop

  # defmacro refute!(flag, expected) when :erlang.map_get(flag, @flag_values) != expected, do: @noop

  # defmacro refute!(flag, expected) when :erlang.map_get(flag, @flag_values) == expected do
  #   heading =
  #     "Expected value of the `#{inspect(flag)}` feature flag not to be `#{inspect(expected)}`."

  #   quote do
  #     raise Ash.Error.Framework.FlagAssertionFailed.exception(
  #             flag: unquote(flag),
  #             heading: unquote(heading)
  #           )
  #   end
  # end
end