@type status() ::
  :internal_error
  | :unauthorized
  | :track_ended
  | :subscription_ended
  | :going_away
  | :expired
  | :too_far_behind
  | :update_failed
  | :malformed_track
  | {:unknown, non_neg_integer()}

@type t() :: %MOQX.Subscription.Completion{
  expected_streams: non_neg_integer() | :unknown,
  processed_streams: non_neg_integer(),
  reason: binary(),
  status: status(),
  status_code: non_neg_integer(),
  timed_out?: boolean()
}