From 230a6838e08bcac28516c5766f40c3e0a537311c Mon Sep 17 00:00:00 2001
From: Yandrik <me@yandrik.dev>
Date: Tue, 5 May 2026 20:44:31 +0200
Subject: [PATCH] fix: fix dfu id mismatch because stale notification

---
 lib/service/firmware_update_service.dart      | 37 +++++++++++++++++--
 .../service/firmware_update_service_test.dart | 33 +++++++++++++++++
 2 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/lib/service/firmware_update_service.dart b/lib/service/firmware_update_service.dart
index 2e96597..48a40fd 100644
--- a/lib/service/firmware_update_service.dart
+++ b/lib/service/firmware_update_service.dart
@@ -527,10 +527,33 @@ class FirmwareUpdateService {
   Future<DfuBootloaderStatus> _sendStartAndWaitForStatus(
     BootloaderDfuStartPayload payload, {
     required Duration timeout,
-  }) {
-    return _writeControlAndWaitForStatus(
-      BootloaderDfuProtocol.encodeStartPayload(payload),
+  }) async {
+    final eventCount = _statusEventCount;
+    final encodedPayload = BootloaderDfuProtocol.encodeStartPayload(payload);
+    _log.fine(
+      'Writing DFU START command for session ${payload.sessionId} '
+      '(len=${encodedPayload.length})',
+    );
+    final result = await _transport.writeControl(encodedPayload);
+    if (result.isErr()) {
+      _log.warning('DFU START write failed: ${result.unwrapErr()}');
+      throw _DfuFailure(
+        'Failed to write bootloader control command: ${result.unwrapErr()}',
+      );
+    }
+    return _waitForStatus(
+      afterEventCount: eventCount,
       timeout: timeout,
+      acceptStatus: (status) {
+        if (status.sessionId == payload.sessionId) {
+          return true;
+        }
+        _log.fine(
+          'Ignoring stale START status for session ${status.sessionId}; '
+          'waiting for session ${payload.sessionId}',
+        );
+        return false;
+      },
     );
   }
 
@@ -708,6 +731,7 @@ class FirmwareUpdateService {
     required int afterEventCount,
     required Duration timeout,
     bool recoverable = false,
+    bool Function(DfuBootloaderStatus status)? acceptStatus,
   }) async {
     final deadline = DateTime.now().add(timeout);
     var observedEvents = afterEventCount;
@@ -722,7 +746,12 @@ class FirmwareUpdateService {
           'session=${_latestStatus!.sessionId}, offset=${_latestStatus!.expectedOffset}, '
           'code=${_statusLabel(_latestStatus!)}',
         );
-        return _latestStatus!;
+        final status = _latestStatus!;
+        if (acceptStatus == null || acceptStatus(status)) {
+          return status;
+        }
+        observedEvents = _statusEventCount;
+        continue;
       }
 
       final remaining = deadline.difference(DateTime.now());
diff --git a/test/service/firmware_update_service_test.dart b/test/service/firmware_update_service_test.dart
index 4baebdc..fc9beea 100644
--- a/test/service/firmware_update_service_test.dart
+++ b/test/service/firmware_update_service_test.dart
@@ -307,6 +307,33 @@ void main() {
       await transport.dispose();
     });
 
+    test('ignores stale previous-session status while waiting for START',
+        () async {
+      final image = _validImage(80);
+      final transport = _FakeFirmwareUpdateTransport(
+        totalBytes: image.length,
+        staleStartStatusSessionId: 20,
+      );
+      final service = FirmwareUpdateService(
+        transport: transport,
+        defaultStatusTimeout: const Duration(milliseconds: 100),
+      );
+
+      final result = await service.startUpdate(
+        imageBytes: image,
+        sessionId: 21,
+      );
+
+      expect(result.isOk(), isTrue);
+      expect(
+          transport.controlWrites.first.first, universalShifterDfuOpcodeStart);
+      expect(transport.dataWrites.first[0], 21);
+      expect(service.currentProgress.state, DfuUpdateState.completed);
+
+      await service.dispose();
+      await transport.dispose();
+    });
+
     test('fails with bootloader status error on rejected START', () async {
       final image = _validImage(40);
       final transport = _FakeFirmwareUpdateTransport(
@@ -410,6 +437,7 @@ class _FakeFirmwareUpdateTransport implements FirmwareUpdateTransport {
     this.suppressFirstDataStatus = false,
     this.failDataWriteAtOffsetOnce,
     this.resetSessionOnRecoveryStatus = false,
+    this.staleStartStatusSessionId,
     this.suppressFinishStatus = false,
     this.disconnectAfterFinish = true,
     this.finishStatusCode = DfuBootloaderStatusCode.ok,
@@ -425,6 +453,7 @@ class _FakeFirmwareUpdateTransport implements FirmwareUpdateTransport {
   final bool suppressFirstDataStatus;
   final int? failDataWriteAtOffsetOnce;
   final bool resetSessionOnRecoveryStatus;
+  final int? staleStartStatusSessionId;
   final bool suppressFinishStatus;
   final bool disconnectAfterFinish;
   final DfuBootloaderStatusCode finishStatusCode;
@@ -502,6 +531,10 @@ class _FakeFirmwareUpdateTransport implements FirmwareUpdateTransport {
     if (opcode == universalShifterDfuOpcodeStart) {
       _sessionId = payload[17];
       _expectedOffset = 0;
+      final staleSessionId = staleStartStatusSessionId;
+      if (staleSessionId != null) {
+        _scheduleStatus(DfuBootloaderStatusCode.ok, staleSessionId, 0);
+      }
       _scheduleStatus(startStatusCode, _sessionId, 0);
     } else if (opcode == universalShifterDfuOpcodeGetStatus) {
       if (resetSessionOnRecoveryStatus && _connectCount > 1) {