Auto-lock wallet after 10 minutes in background

lib/app.dart

@@ -8,6 +8,7 @@ import 'package:desktop_window_bootstrap/desktop_window_bootstrap.dart';
 import 'src/app_bootstrap.dart';
 import 'src/core/layout/app_layout.dart';
 import 'src/core/motion/onboarding_motion.dart';
+import 'src/core/security/wallet_lock_controller.dart';
 import 'src/core/theme/app_theme_host.dart';
 import 'src/core/theme/legacy_material_theme.dart';
 import 'src/core/widgets/network_fallback_toast.dart';
@@ -591,21 +592,23 @@ class ZcashWalletApp extends ConsumerWidget {
           // (buttons, TextFields) win the gesture arena first, keeping
           // focused buttons focused when re-clicked.
           child: _RpcEndpointFailoverToastListener(
-            child: DesktopWindowTitlebarSafeArea(
-              child: GestureDetector(
-                onTap: () {
-                  // Leaf-only: skip when the primary focus is a
-                  // `FocusScopeNode` rather than a concrete `FocusNode`.
-                  // Unfocusing the scope itself strips the scope's
-                  // "most-recently-focused child" memory, which leaves the
-                  // next Tab with no deterministic starting point.
-                  final primary = FocusManager.instance.primaryFocus;
-                  if (primary != null && primary is! FocusScopeNode) {
-                    primary.unfocus();
-                  }
-                },
-                behavior: HitTestBehavior.translucent,
-                child: child!,
+            child: AutoLockObserver(
+              child: DesktopWindowTitlebarSafeArea(
+                child: GestureDetector(
+                  onTap: () {
+                    // Leaf-only: skip when the primary focus is a
+                    // `FocusScopeNode` rather than a concrete `FocusNode`.
+                    // Unfocusing the scope itself strips the scope's
+                    // "most-recently-focused child" memory, which leaves the
+                    // next Tab with no deterministic starting point.
+                    final primary = FocusManager.instance.primaryFocus;
+                    if (primary != null && primary is! FocusScopeNode) {
+                      primary.unfocus();
+                    }
+                  },
+                  behavior: HitTestBehavior.translucent,
+                  child: child!,
+                ),
               ),
             ),
           ),

lib/src/core/layout/app_main_sidebar.dart

@@ -6,6 +6,7 @@ import '../../providers/account_provider.dart';
 import '../../providers/app_security_provider.dart';
 import '../../providers/sync_provider.dart';
 import '../profile_pictures.dart';
+import '../security/wallet_lock_controller.dart';
 import '../theme/app_theme.dart';
 import '../widgets/app_icon.dart';
 import '../widgets/app_profile_picture.dart';
@@ -44,12 +45,16 @@ class _AppMainSidebarState extends ConsumerState<AppMainSidebar> {
     });
 
     try {
-      securityNotifier.lock();
-      accountNotifier.clearSensitiveStateForLock();
+      final lockFuture = lockWalletSession(
+        securityNotifier: securityNotifier,
+        accountNotifier: accountNotifier,
+        syncNotifier: syncNotifier,
+        awaitSync: true,
+      );
       if (mounted) {
         context.go('/unlock');
       }
-      await syncNotifier.clearSensitiveStateForLock();
+      await lockFuture;
     } finally {
       if (mounted) {
         setState(() {

lib/src/core/security/wallet_lock_controller.dart

@@ -0,0 +1,91 @@
+import 'dart:async';
+
+import 'package:flutter/widgets.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+import '../../../main.dart' show log;
+import '../../providers/account_provider.dart';
+import '../../providers/app_security_provider.dart';
+import '../../providers/sync_provider.dart';
+
+const Duration kAutoLockBackgroundTimeout = Duration(minutes: 10);
+
+bool shouldAutoLock({
+  required DateTime? hiddenAt,
+  required DateTime now,
+  Duration threshold = kAutoLockBackgroundTimeout,
+}) {
+  if (hiddenAt == null) return false;
+  return now.difference(hiddenAt) >= threshold;
+}
+
+Future<void> lockWalletSession({
+  required AppSecurityNotifier securityNotifier,
+  required AccountNotifier accountNotifier,
+  required SyncNotifier syncNotifier,
+  bool awaitSync = false,
+}) async {
+  securityNotifier.lock();
+  accountNotifier.clearSensitiveStateForLock();
+  final syncFuture = syncNotifier.clearSensitiveStateForLock();
+  if (awaitSync) {
+    await syncFuture;
+  } else {
+    unawaited(syncFuture);
+  }
+}
+
+class AutoLockObserver extends ConsumerStatefulWidget {
+  const AutoLockObserver({super.key, required this.child});
+
+  final Widget child;
+
+  @override
+  ConsumerState<AutoLockObserver> createState() => _AutoLockObserverState();
+}
+
+class _AutoLockObserverState extends ConsumerState<AutoLockObserver> {
+  AppLifecycleListener? _listener;
+  DateTime? _hiddenAt;
+
+  @override
+  void initState() {
+    super.initState();
+    _listener = AppLifecycleListener(onHide: _onHide, onShow: _onShow);
+  }
+
+  @override
+  void dispose() {
+    _listener?.dispose();
+    _listener = null;
+    super.dispose();
+  }
+
+  void _onHide() {
+    final security = ref.read(appSecurityProvider);
+    if (!security.isUnlocked) return;
+    _hiddenAt = DateTime.now();
+  }
+
+  void _onShow() {
+    final hiddenAt = _hiddenAt;
+    _hiddenAt = null;
+    if (hiddenAt == null) return;
+    final security = ref.read(appSecurityProvider);
+    if (!security.isUnlocked) return;
+    final now = DateTime.now();
+    if (!shouldAutoLock(hiddenAt: hiddenAt, now: now)) return;
+    log(
+      'AutoLock: hidden for ${now.difference(hiddenAt)}, '
+      'locking wallet session',
+    );
+    lockWalletSession(
+      securityNotifier: ref.read(appSecurityProvider.notifier),
+      accountNotifier: ref.read(accountProvider.notifier),
+      syncNotifier: ref.read(syncProvider.notifier),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) => widget.child;
+}