defmodule PerfAgent do
  @moduledoc """
  Entry point for Perf Agent
  """
  use Application

  @version Mix.Project.config[:version]

  @doc """
  Application callback to start Perf Agent
  """
  @spec start(Application.app, Application.start_type) :: :ok | {:error, term}
  def start(_type \\ :normal, _args \\ []) do
    import Supervisor.Spec, warn: false

    children = case configured? do
      true ->
        # Queue is the shared agent between the recorder and the poller
        {:ok, queue} = PerfAgent.TransactionQueue.start_link()
        # Starting hackney pool for requests
        PerfAgent.Network.start_pool()
        [
          worker(PerfAgent.Poller, [queue], restart: :transient),
          worker(PerfAgent.Recorder, [queue], restart: :transient)
        ]
      false -> []
    end

    opts = [strategy: :one_for_one, name: PerfAgent.Supervisor]
    Supervisor.start_link(children, opts)
  end

  @doc """
  Checks if the required configuration params are set.
  Application will take no action if not set.
  """
  @spec configured? :: boolean
  def configured? do
    Application.get_env(:perf_agent, :api_key) != nil
  end

  def version(), do: @version
end