retort

defmodule Retort.AMQP.Default do
  @moduledoc """
  Uses the `AMQP` package to setup a channel and queue.
  """

  @behaviour Retort.AMQP

  # Functions

  @spec consume(%AMQP.Channel{}, String.t) :: {:ok, String.t}
  def consume(channel = %AMQP.Channel{}, queue) when is_binary(queue), do: AMQP.Basic.consume(channel, queue)

  @spec declare_queue(%AMQP.Channel{}, String.t) ::
        {:ok, %{queue: String.t, message_count: non_neg_integer, consumer_count: non_neg_integer}}
  def declare_queue(channel = %AMQP.Channel{}, queue) when is_binary(queue) do
    AMQP.Queue.declare(channel, queue, durable: false)
  end

  @spec open(%AMQP.Connection{}) :: {:ok, %AMQP.Channel{}}
  def open(connection = %AMQP.Connection{}), do: AMQP.Channel.open(connection)

  @spec prefetch_count(%AMQP.Channel{}, pos_integer) :: :ok
  def prefetch_count(channel = %AMQP.Channel{}, prefetch_count)
      when is_integer(prefetch_count) and prefetch_count > 0 do
    AMQP.Basic.qos(channel, prefetch_count: prefetch_count)
  end
end