@callback handle_connect(state :: term()) :: {:ok, term()}

@callback handle_disconnect(reason :: term(), state :: term()) :: {:ok, term()}

@callback handle_error(error :: term(), event :: term()) :: any()

@callback handle_event(
  type :: String.t(),
  payload :: term(),
  meta :: map(),
  state :: term()
) ::
  {:ack, term()}
  | {:nack, term()}
  | {:nack, term(), [{:delay_ms, non_neg_integer()}]}
  | {:term, term()}
  | {:term, term(), String.t()}
  | {:defer, term()}

@callback handle_ready(state :: term()) :: {:ok, term()}

@callback init(opts :: keyword()) :: {:ok, term()} | {:error, term()}