@spec enqueue(map(), EtherCAT.Bus.Link.Submission.t()) :: map()

Enqueue a submission into the appropriate queue based on its staleness budget.

Realtime submissions (those with a stale_after_us) go into the realtime queue. All others go into the reliable queue.

@spec expire_stale_realtime(map(), String.t()) :: map()

Expire stale realtime submissions, replying {:error, :expired} to each.

Returns the updated data with expired submissions removed from the queue.

@spec flush_all(map(), term()) :: map()

Flush all queued submissions, replying with the given error to each caller.

Returns the updated data with empty queues.

@spec match_and_reply([EtherCAT.Bus.Datagram.t()], [{:gen_statem.from(), [byte()]}]) ::
  :ok | :mismatch

Match response datagrams against the awaiting list and reply to all callers.

Returns :ok if all expected datagrams are present, :mismatch otherwise.

@spec max_datagram_bytes() :: pos_integer()

Maximum datagram payload per frame.

@spec next_dispatch(map()) ::
  {:realtime, EtherCAT.Bus.Link.Submission.t(), map()}
  | {:reliable, [EtherCAT.Bus.Link.Submission.t()], map()}
  | :empty

Take the next dispatch unit from the queues.

Realtime submissions have priority and are dispatched one at a time. Reliable submissions are batched into a single frame up to 1400 bytes.

Returns:

• {:realtime, submission, updated_data} — one realtime submission
• {:reliable, batch, updated_data} — list of reliable submissions
• :empty — nothing to dispatch

@spec prepare_realtime(EtherCAT.Bus.Link.Submission.t(), non_neg_integer()) ::
  {[EtherCAT.Bus.Datagram.t()], [{:gen_statem.from(), [byte()]}],
   non_neg_integer()}

Build the awaiting list and stamped datagrams for a realtime submission.

@spec prepare_reliable([EtherCAT.Bus.Link.Submission.t()], non_neg_integer()) ::
  {[EtherCAT.Bus.Datagram.t()], [{:gen_statem.from(), [byte()]}],
   non_neg_integer()}

Build the awaiting list and stamped datagrams for a reliable batch.

@spec queue_depth(map(), :realtime | :reliable) :: non_neg_integer()

Queue depth for a given class.

@spec reply_awaiting([{:gen_statem.from(), [byte()]}], term()) :: :ok

Reply to all awaiting callers in an exchange with the given result.

@spec reply_settle_callers([term()], term()) :: :ok

Reply to settle callers.

@spec reply_submissions([EtherCAT.Bus.Link.Submission.t()], term()) :: :ok

Reply to a list of submissions with the given result.

@spec stamp_indices([EtherCAT.Bus.Datagram.t()], non_neg_integer()) ::
  {[EtherCAT.Bus.Datagram.t()], non_neg_integer()}

Stamp datagrams with sequential byte-wrapping indices.

@spec submission_class(EtherCAT.Bus.Link.Submission.t()) :: :realtime | :reliable

Classify a submission as :realtime or :reliable.