defmodule BencheeAsync do
  @moduledoc """
  Documentation for `BencheeAsync`.
  """
  alias BencheeAsync.Reporter

  def run(config, opts \\ []) do
    Reporter.clear()
    user_bef_scenario_hook = Keyword.get(opts, :before_scenario)
    user_aft_scenario_hook = Keyword.get(opts, :after_scenario)
    user_bef_each = Keyword.get(opts, :before_each)

    # inject our own reporting hooks
    opts =
      opts
      |> Keyword.put(:before_each, fn input ->
        Reporter.maybe_enable()

        if user_bef_each != nil do
          user_bef_each.(input)
        end

        Reporter.reset_timer()

        input
      end)
      |> Keyword.put(:before_scenario, fn input ->
        if user_bef_scenario_hook != nil do
          user_bef_scenario_hook.(input)
        end

        input
      end)
      |> Keyword.put(:after_scenario, fn input ->
        Reporter.disable()

        if user_aft_scenario_hook != nil do
          user_aft_scenario_hook.(input)
        end

        input
      end)

    suite =
      opts
      |> Benchee.init()
      |> Benchee.system()
      |> then(fn suite ->
        Enum.reduce(config, suite, fn
          {k, func}, acc when is_function(func) ->
            before_scenario = fn input ->
              Reporter.set_scenario(k, input)
              input
            end

            Benchee.benchmark(acc, k, {func, before_scenario: before_scenario})

          {k, {func, opts}}, acc ->
            user_local_bef_scenario = Keyword.get(opts, :before_scenario)

            opts =
              Keyword.put(opts, :before_scenario, fn input ->
                Reporter.set_scenario(k, input)

                if user_local_bef_scenario != nil do
                  user_local_bef_scenario.(input)
                else
                  input
                end
              end)

            Benchee.benchmark(acc, k, {func, opts})

            # v = case v do
            #   {func, local_hooks} when is_list(local_hooks) ->
            #     user_local_bef_scenario = Keyword.get(local_hooks, :before_scenario)

            #     local_bef_scenario = if user_local_bef_scenario do
            #       new_bef_scenario = fn input ->

            #       end
            #       {func, Keyword.put(:before_scenario, )}

            #     else
            #       fn input  ->
            #          Reporter.set_scenario(k)
            #       end
            #     end
            #     {func, Keyword.put(:before_scenario, )}
            #   _ ->
            #     # v is function only
            #     {k, {v, before_scenario: to_inject}}
            # end
            # Benchee.benchmark(acc, k, v)
        end)
      end)
      |> then(fn suite ->
        # ignore warmup timings
        if suite.configuration.warmup > 0 do
          Reporter.ignore_ms(suite.configuration.warmup / (1000 * 1000))
        end

        suite
      end)
      |> Benchee.collect()
      |> then(fn suite ->
        updated_scenarios =
          for scenario <- suite.scenarios,
              run_time_data = scenario.run_time_data do
            samples = Reporter.get_samples(scenario.name, scenario.input)

            %{scenario | run_time_data: Map.put(run_time_data, :samples, samples)}
          end

        %{suite | scenarios: updated_scenarios}
      end)
      |> Benchee.statistics()
      |> Benchee.relative_statistics()
      |> Benchee.Formatter.output()

    suite
  end
end