The reader HTTP-GETs on each scan and beeps/acts on our JSON reply (host-in-the-
loop, synchronous). New route GET/POST /qa/mcardsea.php parses the SDK query,
runs the scan through the read dispatcher (permit match -> permit flow; else
transient exit), and replies the SDK verdict: status 1=valid (beep 2x) /
0=invalid (beep 1x), output, time-sync.
Refactored the read flows to return a ReadOutcome {accepted, direction, reason}
so the reply reflects the real accept/reject decision (ReadDispatcher.dispatch,
ExitFlow.handleAt, PermitFlow.run). Fire-and-forget readers ignore it.
Reader's lane is keyed off its serial (cjihao) as lane_devices.id for now;
endpoint is public (reader has no auth, on the device subnet).
Verified via inject: valid permit QR -> status:1 + open; re-scan -> permit exit;
unknown QR -> status:0; barrier-less lane -> status:0.
A credential read now routes by what the credential IS: matches a permit
(card/QR credential or a bound plate) -> permit flow; else -> transient exit
flow. Lane resolved once (readerLaneWithAccess); ExitFlow.onRead -> handleAt so
the dispatcher owns lane resolution.
Permit direction is inferred from session state for that car (the read value is
the per-car session key): no open session -> ENTRY (enforce maxConcurrent, sign
vehicle_entry, open); open -> EXIT (sign vehicle_exit, open, close). Fleet
permit = one session per car; anti-passback falls out naturally.
maxConcurrent enforced as a fold over the signed ledger (null = unbound).
Validity window + status + plate-OR-card identity as designed. No ticket/fee;
every use is a signed event carrying permitId. Refusals (revoked / out-of-window
/ at-capacity) are signed anomalies, barrier stays closed.
Verified against stubs: card entry -> inferred exit; fleet cap 2 (F3 rejected
at 2/2, then admitted after F1 exits); plate-bound opens; revoked rejects;
unknown credential falls through to exit reject; verifyChain ok.