trackr

defmodule Trackr.Core.Server do
  use GenServer
  require Logger

  def init(destinations) do
    {:ok, destinations}
  end

  def handle_cast({:track, info}, state) do
    {action, metadata, headers } = info
    track(action, metadata, headers, state)
    {:noreply, state}
  end

  def handle_info(_msg, state) do
    {:noreply, state}
  end

  defp track(action, metadata, headers, destinations) do
    body = %{action: action, metadata: metadata}
    fire(destinations, body, headers)
  end

  defp fire(destinations, payload, headers) do
    destinations
    |> get_destinations()
    |> Stream.map(fn destination -> destination end)
    |> Enum.map(fn destination ->
      Task.async(fn ->
        url = Map.get(destination, :url)
        method = Map.get(destination, :method)
        headers = Map.get(destination, :headers) ++ headers

        apply(Trackr.Services.HTTP, String.to_atom(method), [url,payload, headers])
      end)
    end)
  end

  defp get_destinations(destinations) do
    destinations
    |> Enum.flat_map(fn destination -> destination end)
  end
end