add alot

lib/app/app.dart

@@ -1,22 +1,50 @@
 import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
 import 'package:kooltab2/theme.dart';
+import 'package:kooltab2/utils/app_update_util.dart';
 
-class KoolTabApp extends StatelessWidget {
+class KoolTabApp extends StatefulWidget {
-  const KoolTabApp({
+  const KoolTabApp({super.key, required this.router});
-    super.key,
-    required this.router,
-  });
 
   final GoRouter router;
 
+  @override
+  State<KoolTabApp> createState() => _KoolTabAppState();
+}
+
+class _KoolTabAppState extends State<KoolTabApp> {
+  @override
+  void initState() {
+    super.initState();
+
+    _checkForUpdates();
+  }
+
+  Future<void> _checkForUpdates() async {
+    final updater = AppUpdateUtil(serverUrl: "http://localhost:3000/");
+
+    try {
+      final update = await updater.checkForUpdate();
+
+      if (update == null) {
+        return;
+      }
+
+      debugPrint("Update available: ${update.version}");
+
+      // TODO:
+      // Show update dialog here
+    } catch (e) {
+      debugPrint("Update check failed: $e");
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp.router(
       title: 'KoolTab',
       debugShowCheckedModeBanner: false,
-      routerConfig: router,
+      routerConfig: widget.router,
-      // theme: lightTheme,
       theme: darkTheme,
     );
   }

lib/app/router.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
+import 'package:kooltab2/views/settings_view.dart';
 
 import '../viewmodels/pin_lock_view_model.dart';
 import '../views/bar_screen_view.dart';
@@ -31,6 +32,10 @@ GoRouter createAppRouter(PinLockViewModel pinLockViewModel) {
       return null;
     },
     routes: [
+      GoRoute(
+          path: '/',
+          redirect: (context, state) => '/bar'
+      ),
       GoRoute(
         path: '/lock',
         builder: (context, state) => PinEntryView(
@@ -67,6 +72,11 @@ GoRouter createAppRouter(PinLockViewModel pinLockViewModel) {
         path: '/history',
         builder: (context, state) => const HistoryScreenView(),
       ),
+
+      GoRoute(
+        path: '/settings',
+        builder: (context, state) => const SettingsScreenView(),
+      ),
     ],
   );
 }

lib/database/app_database.dart

@@ -93,6 +93,19 @@ class ClosedTabItems extends Table {
   Set<Column> get primaryKey => {id};
 }
 
+@DataClassName('AppSettingsRow')
+class AppSettingsTable extends Table {
+  @override
+  String get tableName => 'app_settings';
+
+  TextColumn get id => text()();
+  BoolColumn get pinRequired => boolean().withDefault(const Constant(false))();
+  TextColumn get themeMode => text().withDefault(const Constant('system'))();
+
+  @override
+  Set<Column> get primaryKey => {id};
+}
+
 @DriftDatabase(
   tables: [
     Products,
@@ -100,7 +113,9 @@ class ClosedTabItems extends Table {
     TabItems,
 
     ClosedTabs,
-    ClosedTabItems
+    ClosedTabItems,
+
+    AppSettingsTable
   ],
 )
 class AppDatabase extends _$AppDatabase {
@@ -129,6 +144,10 @@ class AppDatabase extends _$AppDatabase {
           await migrator.createTable(closedTabs);
           await migrator.createTable(closedTabItems);
         }
+
+        if (from < 5){
+          await migrator.createTable(appSettingsTable);
+        }
       },
     );
   }

lib/database/app_database.g.dart

@@ -2126,6 +2126,271 @@ class ClosedTabItemsCompanion extends UpdateCompanion<ClosedTabItemRow> {
   }
 }
 
+class $AppSettingsTableTable extends AppSettingsTable
+    with TableInfo<$AppSettingsTableTable, AppSettingsRow> {
+  @override
+  final GeneratedDatabase attachedDatabase;
+  final String? _alias;
+  $AppSettingsTableTable(this.attachedDatabase, [this._alias]);
+  static const VerificationMeta _idMeta = const VerificationMeta('id');
+  @override
+  late final GeneratedColumn<String> id = GeneratedColumn<String>(
+    'id',
+    aliasedName,
+    false,
+    type: DriftSqlType.string,
+    requiredDuringInsert: true,
+  );
+  static const VerificationMeta _pinRequiredMeta = const VerificationMeta(
+    'pinRequired',
+  );
+  @override
+  late final GeneratedColumn<bool> pinRequired = GeneratedColumn<bool>(
+    'pin_required',
+    aliasedName,
+    false,
+    type: DriftSqlType.bool,
+    requiredDuringInsert: false,
+    defaultConstraints: GeneratedColumn.constraintIsAlways(
+      'CHECK ("pin_required" IN (0, 1))',
+    ),
+    defaultValue: const Constant(false),
+  );
+  static const VerificationMeta _themeModeMeta = const VerificationMeta(
+    'themeMode',
+  );
+  @override
+  late final GeneratedColumn<String> themeMode = GeneratedColumn<String>(
+    'theme_mode',
+    aliasedName,
+    false,
+    type: DriftSqlType.string,
+    requiredDuringInsert: false,
+    defaultValue: const Constant('system'),
+  );
+  @override
+  List<GeneratedColumn> get $columns => [id, pinRequired, themeMode];
+  @override
+  String get aliasedName => _alias ?? actualTableName;
+  @override
+  String get actualTableName => $name;
+  static const String $name = 'app_settings';
+  @override
+  VerificationContext validateIntegrity(
+    Insertable<AppSettingsRow> instance, {
+    bool isInserting = false,
+  }) {
+    final context = VerificationContext();
+    final data = instance.toColumns(true);
+    if (data.containsKey('id')) {
+      context.handle(_idMeta, id.isAcceptableOrUnknown(data['id']!, _idMeta));
+    } else if (isInserting) {
+      context.missing(_idMeta);
+    }
+    if (data.containsKey('pin_required')) {
+      context.handle(
+        _pinRequiredMeta,
+        pinRequired.isAcceptableOrUnknown(
+          data['pin_required']!,
+          _pinRequiredMeta,
+        ),
+      );
+    }
+    if (data.containsKey('theme_mode')) {
+      context.handle(
+        _themeModeMeta,
+        themeMode.isAcceptableOrUnknown(data['theme_mode']!, _themeModeMeta),
+      );
+    }
+    return context;
+  }
+
+  @override
+  Set<GeneratedColumn> get $primaryKey => {id};
+  @override
+  AppSettingsRow map(Map<String, dynamic> data, {String? tablePrefix}) {
+    final effectivePrefix = tablePrefix != null ? '$tablePrefix.' : '';
+    return AppSettingsRow(
+      id: attachedDatabase.typeMapping.read(
+        DriftSqlType.string,
+        data['${effectivePrefix}id'],
+      )!,
+      pinRequired: attachedDatabase.typeMapping.read(
+        DriftSqlType.bool,
+        data['${effectivePrefix}pin_required'],
+      )!,
+      themeMode: attachedDatabase.typeMapping.read(
+        DriftSqlType.string,
+        data['${effectivePrefix}theme_mode'],
+      )!,
+    );
+  }
+
+  @override
+  $AppSettingsTableTable createAlias(String alias) {
+    return $AppSettingsTableTable(attachedDatabase, alias);
+  }
+}
+
+class AppSettingsRow extends DataClass implements Insertable<AppSettingsRow> {
+  final String id;
+  final bool pinRequired;
+  final String themeMode;
+  const AppSettingsRow({
+    required this.id,
+    required this.pinRequired,
+    required this.themeMode,
+  });
+  @override
+  Map<String, Expression> toColumns(bool nullToAbsent) {
+    final map = <String, Expression>{};
+    map['id'] = Variable<String>(id);
+    map['pin_required'] = Variable<bool>(pinRequired);
+    map['theme_mode'] = Variable<String>(themeMode);
+    return map;
+  }
+
+  AppSettingsTableCompanion toCompanion(bool nullToAbsent) {
+    return AppSettingsTableCompanion(
+      id: Value(id),
+      pinRequired: Value(pinRequired),
+      themeMode: Value(themeMode),
+    );
+  }
+
+  factory AppSettingsRow.fromJson(
+    Map<String, dynamic> json, {
+    ValueSerializer? serializer,
+  }) {
+    serializer ??= driftRuntimeOptions.defaultSerializer;
+    return AppSettingsRow(
+      id: serializer.fromJson<String>(json['id']),
+      pinRequired: serializer.fromJson<bool>(json['pinRequired']),
+      themeMode: serializer.fromJson<String>(json['themeMode']),
+    );
+  }
+  @override
+  Map<String, dynamic> toJson({ValueSerializer? serializer}) {
+    serializer ??= driftRuntimeOptions.defaultSerializer;
+    return <String, dynamic>{
+      'id': serializer.toJson<String>(id),
+      'pinRequired': serializer.toJson<bool>(pinRequired),
+      'themeMode': serializer.toJson<String>(themeMode),
+    };
+  }
+
+  AppSettingsRow copyWith({String? id, bool? pinRequired, String? themeMode}) =>
+      AppSettingsRow(
+        id: id ?? this.id,
+        pinRequired: pinRequired ?? this.pinRequired,
+        themeMode: themeMode ?? this.themeMode,
+      );
+  AppSettingsRow copyWithCompanion(AppSettingsTableCompanion data) {
+    return AppSettingsRow(
+      id: data.id.present ? data.id.value : this.id,
+      pinRequired: data.pinRequired.present
+          ? data.pinRequired.value
+          : this.pinRequired,
+      themeMode: data.themeMode.present ? data.themeMode.value : this.themeMode,
+    );
+  }
+
+  @override
+  String toString() {
+    return (StringBuffer('AppSettingsRow(')
+          ..write('id: $id, ')
+          ..write('pinRequired: $pinRequired, ')
+          ..write('themeMode: $themeMode')
+          ..write(')'))
+        .toString();
+  }
+
+  @override
+  int get hashCode => Object.hash(id, pinRequired, themeMode);
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      (other is AppSettingsRow &&
+          other.id == this.id &&
+          other.pinRequired == this.pinRequired &&
+          other.themeMode == this.themeMode);
+}
+
+class AppSettingsTableCompanion extends UpdateCompanion<AppSettingsRow> {
+  final Value<String> id;
+  final Value<bool> pinRequired;
+  final Value<String> themeMode;
+  final Value<int> rowid;
+  const AppSettingsTableCompanion({
+    this.id = const Value.absent(),
+    this.pinRequired = const Value.absent(),
+    this.themeMode = const Value.absent(),
+    this.rowid = const Value.absent(),
+  });
+  AppSettingsTableCompanion.insert({
+    required String id,
+    this.pinRequired = const Value.absent(),
+    this.themeMode = const Value.absent(),
+    this.rowid = const Value.absent(),
+  }) : id = Value(id);
+  static Insertable<AppSettingsRow> custom({
+    Expression<String>? id,
+    Expression<bool>? pinRequired,
+    Expression<String>? themeMode,
+    Expression<int>? rowid,
+  }) {
+    return RawValuesInsertable({
+      if (id != null) 'id': id,
+      if (pinRequired != null) 'pin_required': pinRequired,
+      if (themeMode != null) 'theme_mode': themeMode,
+      if (rowid != null) 'rowid': rowid,
+    });
+  }
+
+  AppSettingsTableCompanion copyWith({
+    Value<String>? id,
+    Value<bool>? pinRequired,
+    Value<String>? themeMode,
+    Value<int>? rowid,
+  }) {
+    return AppSettingsTableCompanion(
+      id: id ?? this.id,
+      pinRequired: pinRequired ?? this.pinRequired,
+      themeMode: themeMode ?? this.themeMode,
+      rowid: rowid ?? this.rowid,
+    );
+  }
+
+  @override
+  Map<String, Expression> toColumns(bool nullToAbsent) {
+    final map = <String, Expression>{};
+    if (id.present) {
+      map['id'] = Variable<String>(id.value);
+    }
+    if (pinRequired.present) {
+      map['pin_required'] = Variable<bool>(pinRequired.value);
+    }
+    if (themeMode.present) {
+      map['theme_mode'] = Variable<String>(themeMode.value);
+    }
+    if (rowid.present) {
+      map['rowid'] = Variable<int>(rowid.value);
+    }
+    return map;
+  }
+
+  @override
+  String toString() {
+    return (StringBuffer('AppSettingsTableCompanion(')
+          ..write('id: $id, ')
+          ..write('pinRequired: $pinRequired, ')
+          ..write('themeMode: $themeMode, ')
+          ..write('rowid: $rowid')
+          ..write(')'))
+        .toString();
+  }
+}
+
 abstract class _$AppDatabase extends GeneratedDatabase {
   _$AppDatabase(QueryExecutor e) : super(e);
   $AppDatabaseManager get managers => $AppDatabaseManager(this);
@@ -2134,6 +2399,9 @@ abstract class _$AppDatabase extends GeneratedDatabase {
   late final $TabItemsTable tabItems = $TabItemsTable(this);
   late final $ClosedTabsTable closedTabs = $ClosedTabsTable(this);
   late final $ClosedTabItemsTable closedTabItems = $ClosedTabItemsTable(this);
+  late final $AppSettingsTableTable appSettingsTable = $AppSettingsTableTable(
+    this,
+  );
   @override
   Iterable<TableInfo<Table, Object?>> get allTables =>
       allSchemaEntities.whereType<TableInfo<Table, Object?>>();
@@ -2144,6 +2412,7 @@ abstract class _$AppDatabase extends GeneratedDatabase {
     tabItems,
     closedTabs,
     closedTabItems,
+    appSettingsTable,
   ];
   @override
   StreamQueryUpdateRules get streamUpdateRules => const StreamQueryUpdateRules([
@@ -3677,6 +3946,176 @@ typedef $$ClosedTabItemsTableProcessedTableManager =
       ClosedTabItemRow,
       PrefetchHooks Function()
     >;
+typedef $$AppSettingsTableTableCreateCompanionBuilder =
+    AppSettingsTableCompanion Function({
+      required String id,
+      Value<bool> pinRequired,
+      Value<String> themeMode,
+      Value<int> rowid,
+    });
+typedef $$AppSettingsTableTableUpdateCompanionBuilder =
+    AppSettingsTableCompanion Function({
+      Value<String> id,
+      Value<bool> pinRequired,
+      Value<String> themeMode,
+      Value<int> rowid,
+    });
+
+class $$AppSettingsTableTableFilterComposer
+    extends Composer<_$AppDatabase, $AppSettingsTableTable> {
+  $$AppSettingsTableTableFilterComposer({
+    required super.$db,
+    required super.$table,
+    super.joinBuilder,
+    super.$addJoinBuilderToRootComposer,
+    super.$removeJoinBuilderFromRootComposer,
+  });
+  ColumnFilters<String> get id => $composableBuilder(
+    column: $table.id,
+    builder: (column) => ColumnFilters(column),
+  );
+
+  ColumnFilters<bool> get pinRequired => $composableBuilder(
+    column: $table.pinRequired,
+    builder: (column) => ColumnFilters(column),
+  );
+
+  ColumnFilters<String> get themeMode => $composableBuilder(
+    column: $table.themeMode,
+    builder: (column) => ColumnFilters(column),
+  );
+}
+
+class $$AppSettingsTableTableOrderingComposer
+    extends Composer<_$AppDatabase, $AppSettingsTableTable> {
+  $$AppSettingsTableTableOrderingComposer({
+    required super.$db,
+    required super.$table,
+    super.joinBuilder,
+    super.$addJoinBuilderToRootComposer,
+    super.$removeJoinBuilderFromRootComposer,
+  });
+  ColumnOrderings<String> get id => $composableBuilder(
+    column: $table.id,
+    builder: (column) => ColumnOrderings(column),
+  );
+
+  ColumnOrderings<bool> get pinRequired => $composableBuilder(
+    column: $table.pinRequired,
+    builder: (column) => ColumnOrderings(column),
+  );
+
+  ColumnOrderings<String> get themeMode => $composableBuilder(
+    column: $table.themeMode,
+    builder: (column) => ColumnOrderings(column),
+  );
+}
+
+class $$AppSettingsTableTableAnnotationComposer
+    extends Composer<_$AppDatabase, $AppSettingsTableTable> {
+  $$AppSettingsTableTableAnnotationComposer({
+    required super.$db,
+    required super.$table,
+    super.joinBuilder,
+    super.$addJoinBuilderToRootComposer,
+    super.$removeJoinBuilderFromRootComposer,
+  });
+  GeneratedColumn<String> get id =>
+      $composableBuilder(column: $table.id, builder: (column) => column);
+
+  GeneratedColumn<bool> get pinRequired => $composableBuilder(
+    column: $table.pinRequired,
+    builder: (column) => column,
+  );
+
+  GeneratedColumn<String> get themeMode =>
+      $composableBuilder(column: $table.themeMode, builder: (column) => column);
+}
+
+class $$AppSettingsTableTableTableManager
+    extends
+        RootTableManager<
+          _$AppDatabase,
+          $AppSettingsTableTable,
+          AppSettingsRow,
+          $$AppSettingsTableTableFilterComposer,
+          $$AppSettingsTableTableOrderingComposer,
+          $$AppSettingsTableTableAnnotationComposer,
+          $$AppSettingsTableTableCreateCompanionBuilder,
+          $$AppSettingsTableTableUpdateCompanionBuilder,
+          (
+            AppSettingsRow,
+            BaseReferences<
+              _$AppDatabase,
+              $AppSettingsTableTable,
+              AppSettingsRow
+            >,
+          ),
+          AppSettingsRow,
+          PrefetchHooks Function()
+        > {
+  $$AppSettingsTableTableTableManager(
+    _$AppDatabase db,
+    $AppSettingsTableTable table,
+  ) : super(
+        TableManagerState(
+          db: db,
+          table: table,
+          createFilteringComposer: () =>
+              $$AppSettingsTableTableFilterComposer($db: db, $table: table),
+          createOrderingComposer: () =>
+              $$AppSettingsTableTableOrderingComposer($db: db, $table: table),
+          createComputedFieldComposer: () =>
+              $$AppSettingsTableTableAnnotationComposer($db: db, $table: table),
+          updateCompanionCallback:
+              ({
+                Value<String> id = const Value.absent(),
+                Value<bool> pinRequired = const Value.absent(),
+                Value<String> themeMode = const Value.absent(),
+                Value<int> rowid = const Value.absent(),
+              }) => AppSettingsTableCompanion(
+                id: id,
+                pinRequired: pinRequired,
+                themeMode: themeMode,
+                rowid: rowid,
+              ),
+          createCompanionCallback:
+              ({
+                required String id,
+                Value<bool> pinRequired = const Value.absent(),
+                Value<String> themeMode = const Value.absent(),
+                Value<int> rowid = const Value.absent(),
+              }) => AppSettingsTableCompanion.insert(
+                id: id,
+                pinRequired: pinRequired,
+                themeMode: themeMode,
+                rowid: rowid,
+              ),
+          withReferenceMapper: (p0) => p0
+              .map((e) => (e.readTable(table), BaseReferences(db, table, e)))
+              .toList(),
+          prefetchHooksCallback: null,
+        ),
+      );
+}
+
+typedef $$AppSettingsTableTableProcessedTableManager =
+    ProcessedTableManager<
+      _$AppDatabase,
+      $AppSettingsTableTable,
+      AppSettingsRow,
+      $$AppSettingsTableTableFilterComposer,
+      $$AppSettingsTableTableOrderingComposer,
+      $$AppSettingsTableTableAnnotationComposer,
+      $$AppSettingsTableTableCreateCompanionBuilder,
+      $$AppSettingsTableTableUpdateCompanionBuilder,
+      (
+        AppSettingsRow,
+        BaseReferences<_$AppDatabase, $AppSettingsTableTable, AppSettingsRow>,
+      ),
+      AppSettingsRow,
+      PrefetchHooks Function()
+    >;
 
 class $AppDatabaseManager {
   final _$AppDatabase _db;
@@ -3691,4 +4130,6 @@ class $AppDatabaseManager {
       $$ClosedTabsTableTableManager(_db, _db.closedTabs);
   $$ClosedTabItemsTableTableManager get closedTabItems =>
       $$ClosedTabItemsTableTableManager(_db, _db.closedTabItems);
+  $$AppSettingsTableTableTableManager get appSettingsTable =>
+      $$AppSettingsTableTableTableManager(_db, _db.appSettingsTable);
 }

lib/main.dart

@@ -3,8 +3,10 @@ import 'package:flutter/services.dart';
 import 'package:intl/date_symbol_data_local.dart';
 import 'package:intl/intl.dart';
 import 'package:kooltab2/services/pin_lock_service.dart';
+import 'package:kooltab2/services/settings_service.dart';
 import 'package:kooltab2/viewmodels/history_view_model.dart';
 import 'package:kooltab2/viewmodels/pin_lock_view_model.dart';
+import 'package:kooltab2/viewmodels/settings_view_model.dart';
 import 'package:provider/provider.dart';
 
 import 'app/app.dart';
@@ -40,14 +42,16 @@ Future<void> main() async {
           dispose: (_, database) => database.close(),
         ),
         Provider<ProductService>(
-          create: (context) => DriftProductService(
+          create: (context) =>
-            database: context.read<AppDatabase>(),
+              DriftProductService(database: context.read<AppDatabase>()),
-          ),
         ),
         Provider<BarTabService>(
-          create: (context) => DriftBarTabService(
+          create: (context) =>
-            database: context.read<AppDatabase>(),
+              DriftBarTabService(database: context.read<AppDatabase>()),
         ),
+        Provider<SettingsService>(
+          create: (context) =>
+              DriftSettingsService(database: context.read<AppDatabase>()),
         ),
         ChangeNotifierProvider<ProductListViewModel>(
           create: (context) => ProductListViewModel(
@@ -55,21 +59,21 @@ Future<void> main() async {
           ),
         ),
         ChangeNotifierProvider<BarScreenViewModel>(
-          create: (context) => BarScreenViewModel(
+          create: (context) =>
-            barTabService: context.read<BarTabService>(),
+              BarScreenViewModel(barTabService: context.read<BarTabService>(), productService: context.read<ProductService>()),
-          ),
         ),
         ChangeNotifierProvider<HistoryViewModel>(
           create: (context) =>
               HistoryViewModel(barTabService: context.read<BarTabService>()),
         ),
-        ChangeNotifierProvider<PinLockViewModel>.value(
+        ChangeNotifierProvider<PinLockViewModel>.value(value: pinLockViewModel),
-          value: pinLockViewModel,
+        ChangeNotifierProvider<SettingsViewModel>(
+          create: (context) => SettingsViewModel(
+            settingsService: context.read<SettingsService>(),
+          ),
         ),
       ],
-      child: AppBootstrap(
+      child: AppBootstrap(child: KoolTabApp(router: appRouter)),
-        child: KoolTabApp(router: appRouter),
-      ),
     ),
   );
 }

lib/models/settings.dart

@@ -0,0 +1,26 @@
+enum AppThemeMode { system, light, dark }
+
+class AppSettings {
+  final bool pinRequired;
+  final AppThemeMode themeMode;
+
+  const AppSettings({
+    required this.pinRequired,
+    required this.themeMode,
+  });
+
+  AppSettings copyWith({
+    bool? pinRequired,
+    AppThemeMode? themeMode,
+  }) {
+    return AppSettings(
+      pinRequired: pinRequired ?? this.pinRequired,
+      themeMode: themeMode ?? this.themeMode,
+    );
+  }
+
+  static const AppSettings defaults = AppSettings(
+    pinRequired: false,
+    themeMode: AppThemeMode.system,
+  );
+}

lib/services/bar_tab_service.dart

@@ -231,7 +231,6 @@ class DriftBarTabService implements BarTabService {
       final items = await _getItemsForTab(tabId);
 
       if (items.isEmpty) {
-        // Nothing to settle, leave the tab as-is.
         return;
       }
 
@@ -263,9 +262,6 @@ class DriftBarTabService implements BarTabService {
         ..where((item) => item.tabId.equals(tabId));
 
       await deleteQuery.go();
-
-      // Note: tab status/customerName untouched on purpose — the tab
-      // stays open so it keeps showing in the open tabs list.
     });
   }
 

lib/services/pin_lock_service.dart

@@ -4,9 +4,6 @@ import 'dart:math';
 import 'package:crypto/crypto.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 
-/// Stores and verifies a PIN. The raw PIN is never persisted — only a
-/// salted SHA-256 hash of it, kept in secure storage (Keychain on iOS,
-/// EncryptedSharedPreferences/Keystore on Android).
 class PinLockService {
   PinLockService({FlutterSecureStorage? storage})
     : _storage = storage ?? const FlutterSecureStorage();

lib/services/product_service.dart

@@ -21,6 +21,9 @@ abstract class ProductService {
   Future<void> updateProduct(Product product);
 
   Future<void> deleteProduct(String id);
+
+  Future<void> decreaseStock(String productId, int amount);
+  Future<void> increaseStock(String productId, int amount);
 }
 
 class DriftProductService implements ProductService {
@@ -118,4 +121,39 @@ class DriftProductService implements ProductService {
 
     await query.go();
   }
+
+  @override
+  Future<void> decreaseStock(String productId, int amount) async {
+    final product = await getProductById(productId);
+
+    if (product == null) {
+      throw Exception('Product not found');
+    }
+
+    if (product.stockQuantity < amount) {
+      throw Exception('Not enough stock');
+    }
+
+    await updateProduct(
+      product.copyWith(
+        stockQuantity: product.stockQuantity - amount,
+      ),
+    );
+  }
+
+  @override
+  Future<void> increaseStock(String productId, int amount) async {
+    final product = await getProductById(productId);
+
+    if (product == null) {
+      throw Exception('Product not found');
+    }
+
+    await updateProduct(
+      product.copyWith(
+        stockQuantity: product.stockQuantity + amount,
+      ),
+    );
+  }
+
 }

lib/services/settings_service.dart

@@ -0,0 +1,50 @@
+import 'package:drift/drift.dart';
+
+import '../database/app_database.dart';
+import '../models/settings.dart';
+
+abstract class SettingsService {
+  Future<AppSettings> getSettings();
+
+  Future<void> saveSettings(AppSettings settings);
+}
+
+class DriftSettingsService implements SettingsService {
+  final AppDatabase database;
+  static const _settingsId = 'app_settings';
+
+  DriftSettingsService({required this.database});
+
+  AppSettings _mapRowToSettings(AppSettingsRow row) {
+    return AppSettings(
+      pinRequired: row.pinRequired,
+      themeMode: AppThemeMode.values.firstWhere(
+            (mode) => mode.name == row.themeMode,
+        orElse: () => AppThemeMode.system,
+      ),
+    );
+  }
+
+  @override
+  Future<AppSettings> getSettings() async {
+    final query = database.select(database.appSettingsTable)
+      ..where((s) => s.id.equals(_settingsId));
+
+    final row = await query.getSingleOrNull();
+
+    if (row == null) return AppSettings.defaults;
+
+    return _mapRowToSettings(row);
+  }
+
+  @override
+  Future<void> saveSettings(AppSettings settings) async {
+    await database.into(database.appSettingsTable).insertOnConflictUpdate(
+      AppSettingsTableCompanion.insert(
+        id: _settingsId,
+        pinRequired: Value(settings.pinRequired),
+        themeMode: Value(settings.themeMode.name),
+      ),
+    );
+  }
+}

lib/theme.dart

@@ -63,7 +63,7 @@ final ThemeData darkTheme = ThemeData(
 
   iconButtonTheme: IconButtonThemeData(
     style: IconButton.styleFrom(
-      backgroundColor: Colors.white.withOpacity(0.05),
+      backgroundColor: Colors.white.withValues(alpha: 0.05),
       foregroundColor: Colors.white70,
       shape: RoundedRectangleBorder(
         borderRadius: BorderRadius.circular(AppRadii.md),
@@ -90,7 +90,7 @@ final ThemeData darkTheme = ThemeData(
       elevation: 0,
       backgroundColor: _violet,
       foregroundColor: Colors.white,
-      disabledBackgroundColor: Colors.white.withOpacity(0.06),
+      disabledBackgroundColor: Colors.white.withValues(alpha: 0.06),
       disabledForegroundColor: Colors.white24,
       padding: const EdgeInsets.symmetric(
         horizontal: AppSpacing.xl,
@@ -195,7 +195,7 @@ final ThemeData darkTheme = ThemeData(
 
   navigationBarTheme: NavigationBarThemeData(
     backgroundColor: _surface,
-    indicatorColor: _violet.withOpacity(0.25),
+    indicatorColor: _violet.withValues(alpha: 0.25),
     labelTextStyle: const WidgetStatePropertyAll(
       TextStyle(fontWeight: FontWeight.w600),
     ),
@@ -484,7 +484,7 @@ final ThemeData lightTheme = ThemeData(
 
   iconButtonTheme: IconButtonThemeData(
     style: IconButton.styleFrom(
-      backgroundColor: Colors.black.withOpacity(0.04),
+      backgroundColor: Colors.black.withValues(alpha: 0.04),
       foregroundColor: Colors.black54,
       shape: RoundedRectangleBorder(
         borderRadius: BorderRadius.circular(AppRadii.md),
@@ -511,7 +511,7 @@ final ThemeData lightTheme = ThemeData(
       elevation: 0,
       backgroundColor: _violetL,
       foregroundColor: Colors.white,
-      disabledBackgroundColor: Colors.black.withOpacity(0.06),
+      disabledBackgroundColor: Colors.black.withValues(alpha: 0.06),
       disabledForegroundColor: Colors.black26,
       padding: const EdgeInsets.symmetric(
         horizontal: AppSpacing.xl,
@@ -616,7 +616,7 @@ final ThemeData lightTheme = ThemeData(
 
   navigationBarTheme: NavigationBarThemeData(
     backgroundColor: _surfaceL,
-    indicatorColor: _violetL.withOpacity(0.15),
+    indicatorColor: _violetL.withValues(alpha: 0.15),
     labelTextStyle: const WidgetStatePropertyAll(
       TextStyle(fontWeight: FontWeight.w600),
     ),

lib/utils/app_update_util.dart

@@ -0,0 +1,242 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:crypto/crypto.dart';
+import 'package:http/http.dart' as http;
+// import 'package:open_filex/open_filex.dart';
+
+// import 'package:package_info_plus/package_info_plus.dart';
+import 'package:path_provider/path_provider.dart';
+
+
+class UpdateInfo {
+  final bool update;
+  final String version;
+  final String notes;
+  final bool mandatory;
+  final String sha256;
+  final String download;
+
+
+  UpdateInfo({
+    required this.update,
+    required this.version,
+    required this.notes,
+    required this.mandatory,
+    required this.sha256,
+    required this.download,
+  });
+
+
+  factory UpdateInfo.fromJson(Map<String, dynamic> json) {
+    return UpdateInfo(
+      update: json["update"] ?? false,
+      version: json["version"] ?? "",
+      notes: json["notes"] ?? "",
+      mandatory: json["mandatory"] ?? false,
+      sha256: json["sha256"] ?? "",
+      download: json["download"] ?? "",
+    );
+  }
+}
+
+
+class AppUpdateUtil {
+
+
+  final String serverUrl;
+
+
+  AppUpdateUtil({
+    required this.serverUrl,
+  });
+
+
+  /// Gets the installed app version
+  Future<String> currentVersion() async {
+    // final info =
+    // await PackageInfo.fromPlatform();
+
+    return "test";
+  }
+
+
+  /// Checks the update server
+  Future<UpdateInfo?> checkForUpdate() async {
+    final version =
+    await currentVersion();
+
+
+    final url = Uri.parse(
+      "$serverUrl/api/update?version=$version",
+    );
+
+
+    final response =
+    await http.get(url);
+
+
+    if (response.statusCode != 200) {
+      throw Exception(
+        "Update server unavailable",
+      );
+    }
+
+
+    final data =
+    jsonDecode(response.body);
+
+
+    if (data["update"] != true) {
+      return null;
+    }
+
+
+    return UpdateInfo.fromJson(data);
+  }
+
+
+  /// Downloads the APK
+  Future<File> downloadApk(UpdateInfo update, {
+
+    Function(double progress)? onProgress,
+
+  }) async {
+    final url =
+    update.download.startsWith("http")
+        ? update.download
+        : "$serverUrl${update.download}";
+
+
+    final request =
+    http.Request(
+      "GET",
+      Uri.parse(url),
+    );
+
+
+    final response =
+    await request.send();
+
+
+    if (response.statusCode != 200) {
+      throw Exception(
+        "APK download failed",
+      );
+    }
+
+
+    final total =
+        response.contentLength ?? 0;
+
+
+    int received = 0;
+
+
+    final directory =
+    await getTemporaryDirectory();
+
+
+    final file =
+    File(
+      "${directory.path}/update.apk",
+    );
+
+
+    final sink =
+    file.openWrite();
+
+    await for (final chunk in response.stream) {
+      sink.add(chunk);
+
+      received += chunk.length;
+
+      if (total > 0 && onProgress != null) {
+        onProgress(
+          received / total,
+        );
+      }
+    }
+
+    await sink.close();
+
+    return file;
+  }
+
+
+  /// Verifies APK checksum
+  Future<bool> verifySha256(File file,
+      String expectedHash,) async {
+    final bytes =
+    await file.readAsBytes();
+
+    final digest =
+    sha256.convert(bytes);
+
+    return digest.toString()
+        .toLowerCase()
+        ==
+        expectedHash.toLowerCase();
+  }
+
+
+  /// Opens Android APK installer
+  Future<void> installApk(File file,) async {
+    // final result =
+    // await OpenFilex.open(
+    //   file.path,
+    // );
+    //
+    //
+    // if (result.type != ResultType.done) {
+    //   throw Exception(
+    //     "Could not open APK installer",
+    //   );
+    // }
+  }
+
+
+  /// Full update flow
+  ///
+  /// Returns:
+  /// - null if no update exists
+  /// - UpdateInfo if update is available
+  ///
+  Future<UpdateInfo?> update({
+
+    Function(double progress)? onProgress,
+
+  }) async {
+    final info =
+    await checkForUpdate();
+
+    if (info == null) {
+      return null;
+    }
+
+    final apk =
+    await downloadApk(
+      info,
+      onProgress: onProgress,
+    );
+
+    final valid =
+    await verifySha256(
+      apk,
+      info.sha256,
+    );
+
+    if (!valid) {
+      throw Exception(
+        "APK checksum mismatch",
+      );
+    }
+
+    await installApk(
+      apk,
+    );
+
+    return info;
+  }
+
+}

lib/viewmodels/bar_screen_view_model.dart

@@ -8,9 +8,11 @@ import '../services/product_service.dart';
 
 class BarScreenViewModel extends ChangeNotifier {
   final BarTabService barTabService;
+  final ProductService productService;
 
   BarScreenViewModel({
     required this.barTabService,
+    required this.productService,
   });
 
   List<BarTab> _tabs = [];
@@ -74,9 +76,7 @@ class BarScreenViewModel extends ChangeNotifier {
   }
 
   Future<void> createTab(String customerName) async {
-    final tab = await barTabService.createTab(
+    final tab = await barTabService.createTab(customerName: customerName);
-      customerName: customerName,
-    );
 
     _selectedTabId = tab.id;
     await _reloadTabs();
@@ -87,23 +87,34 @@ class BarScreenViewModel extends ChangeNotifier {
 
     if (tab == null) return;
 
+    if (product.stockQuantity <= 0) {
+      throw Exception('Product is out of stock.');
+    }
+
     await barTabService.addProductToTab(
       tabId: tab.id,
       product: product,
     );
 
+    await productService.decreaseStock(product.id, 1);
+
     await _reloadTabs();
   }
 
-  Future<void> changeItemQuantity(
+  Future<void> changeItemQuantity(TabItem item, int quantity) async {
-      TabItem item,
+    final difference = quantity - item.quantity;
-      int quantity,
+
-      ) async {
     await barTabService.updateTabItemQuantity(
       tabItemId: item.id,
       quantity: quantity,
     );
 
+    if (difference > 0) {
+      await productService.decreaseStock(item.productId, difference);
+    } else if (difference < 0) {
+      await productService.increaseStock(item.productId, -difference);
+    }
+
     await _reloadTabs();
   }
 
@@ -126,7 +137,8 @@ class BarScreenViewModel extends ChangeNotifier {
   Future<void> _reloadTabs() async {
     _tabs = await barTabService.getOpenTabs();
 
-    if (_selectedTabId == null || !_tabs.any((tab) => tab.id == _selectedTabId)) {
+    if (_selectedTabId == null ||
+        !_tabs.any((tab) => tab.id == _selectedTabId)) {
       _selectedTabId = _tabs.isEmpty ? null : _tabs.first.id;
     }
 

lib/viewmodels/product_list_view_model.dart

@@ -56,6 +56,20 @@ class ProductListViewModel extends ChangeNotifier {
       _isLoading = false;
       notifyListeners();
     }
+
+    try {
+      _products = await productService.getProducts();
+
+      debugPrint(
+        _products.map((p) => '${p.name}: ${p.stockQuantity}').join('\n'),
+      );
+    } catch (_) {
+      _errorMessage = 'Could not load products.';
+    } finally {
+      _hasLoaded = true;
+      _isLoading = false;
+      notifyListeners();
+    }
   }
 
   Future<void> addProduct({

lib/viewmodels/settings_view_model.dart

@@ -0,0 +1,66 @@
+import 'package:flutter/foundation.dart';
+
+import '../models/settings.dart';
+import '../services/settings_service.dart';
+
+class SettingsViewModel extends ChangeNotifier {
+  final SettingsService settingsService;
+
+  SettingsViewModel({required this.settingsService});
+
+  AppSettings _settings = AppSettings.defaults;
+  bool _isLoading = false;
+  bool _hasLoaded = false;
+  String? _errorMessage;
+
+  AppSettings get settings => _settings;
+  bool get isLoading => _isLoading;
+  bool get hasLoaded => _hasLoaded;
+  String? get errorMessage => _errorMessage;
+
+  Future<void> ensureLoaded() async {
+    if (_hasLoaded || _isLoading) return;
+    await load();
+  }
+
+  Future<void> load() async {
+    if (_isLoading) return;
+
+    _isLoading = true;
+    _errorMessage = null;
+    notifyListeners();
+
+    try {
+      _settings = await settingsService.getSettings();
+    } catch (_) {
+      _errorMessage = 'Could not load settings.';
+    } finally {
+      _hasLoaded = true;
+      _isLoading = false;
+      notifyListeners();
+    }
+  }
+
+  /// Just flips the preference flag. Caller is responsible for having
+  /// already set/verified the actual PIN via PinLockViewModel first.
+  Future<void> updatePinRequired(bool value) =>
+      _save(_settings.copyWith(pinRequired: value));
+
+  Future<void> updateThemeMode(AppThemeMode mode) =>
+      _save(_settings.copyWith(themeMode: mode));
+
+  Future<void> _save(AppSettings updated) async {
+    final previous = _settings;
+    _settings = updated;
+    _errorMessage = null;
+    notifyListeners();
+
+    try {
+      await settingsService.saveSettings(updated);
+    } catch (_) {
+      _settings = previous;
+      _errorMessage = 'Could not save settings.';
+      notifyListeners();
+    }
+  }
+}

lib/views/bar_screen_view.dart

@@ -1,6 +1,4 @@
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
-import 'package:flutter/widget_previews.dart';
 import 'package:go_router/go_router.dart';
 import 'package:kooltab2/viewmodels/pin_lock_view_model.dart';
 import 'package:kooltab2/viewmodels/product_list_view_model.dart';
@@ -43,6 +41,12 @@ class BarScreenView extends StatelessWidget {
             icon: const Icon(Icons.refresh_rounded),
           ),
           const SizedBox(width: 6),
+          IconButton(
+            tooltip: 'Settings',
+            onPressed: () => context.go('/settings'),
+            icon: const Icon(Icons.settings),
+          ),
+          const SizedBox(width: 6),
           IconButton(
             tooltip: 'logout',
             onPressed: (){
@@ -234,12 +238,12 @@ class _ProductGrid extends StatelessWidget {
               padding: const EdgeInsets.all(20),
               decoration: BoxDecoration(
                 shape: BoxShape.circle,
-                color: scheme.onSurface.withOpacity(0.05),
+                color: scheme.onSurface.withValues(alpha: 0.05),
               ),
               child: Icon(
                 Icons.inventory_2_outlined,
                 size: 40,
-                color: scheme.onSurface.withOpacity(0.3),
+                color: scheme.onSurface.withValues(alpha: 0.3),
               ),
             ),
             const SizedBox(height: 16),
@@ -280,7 +284,7 @@ class _ProductGrid extends StatelessWidget {
                       vertical: 4,
                     ),
                     decoration: BoxDecoration(
-                      color: scheme.onSurface.withOpacity(0.06),
+                      color: scheme.onSurface.withValues(alpha: 0.06),
                       borderRadius: BorderRadius.circular(999),
                     ),
                     child: Row(
@@ -289,7 +293,7 @@ class _ProductGrid extends StatelessWidget {
                         Icon(
                           Icons.info_outline_rounded,
                           size: 14,
-                          color: scheme.onSurface.withOpacity(0.5),
+                          color: scheme.onSurface.withValues(alpha: 0.5),
                         ),
                         const SizedBox(width: 4),
                         Flexible(
@@ -369,7 +373,7 @@ class _ProductTile extends StatelessWidget {
     return Container(
       decoration: BoxDecoration(
         borderRadius: BorderRadius.circular(16),
-        border: Border.all(color: scheme.onSurface.withOpacity(0.08), width: 1),
+        border: Border.all(color: scheme.onSurface.withValues(alpha: 0.08), width: 1),
       ),
       child: ClipRRect(
         borderRadius: BorderRadius.circular(15),
@@ -396,7 +400,7 @@ class _ProductTile extends StatelessWidget {
                         Icon(
                           Icons.image_not_supported_outlined,
                           size: 34,
-                          color: scheme.onSurface.withOpacity(0.3),
+                          color: scheme.onSurface.withValues(alpha: 0.3),
                         ),
                         const SizedBox(height: 6),
                         Text(
@@ -406,9 +410,6 @@ class _ProductTile extends StatelessWidget {
                       ],
                     ),
                   ),
-                  // Scrim stays black regardless of theme — it's for legibility
-                  // of the (usually light/photographic) image beneath it, not
-                  // themed UI chrome.
                   if (_hasImage)
                     Positioned.fill(
                       child: DecoratedBox(
@@ -418,7 +419,7 @@ class _ProductTile extends StatelessWidget {
                             end: Alignment.bottomCenter,
                             colors: [
                               Colors.transparent,
-                              Colors.black.withOpacity(0.35),
+                              Colors.black.withValues(alpha: 0.35),
                             ],
                             stops: const [0.6, 1.0],
                           ),
@@ -541,7 +542,7 @@ class _TabPanelState extends State<_TabPanel> {
                     vertical: 2,
                   ),
                   decoration: BoxDecoration(
-                    color: scheme.onSurface.withOpacity(0.06),
+                    color: scheme.onSurface.withValues(alpha: 0.06),
                     borderRadius: BorderRadius.circular(999),
                   ),
                   child: Text(
@@ -577,7 +578,7 @@ class _TabPanelState extends State<_TabPanel> {
                     Icon(
                       Icons.receipt_long_outlined,
                       size: 36,
-                      color: scheme.onSurface.withOpacity(0.25),
+                      color: scheme.onSurface.withValues(alpha: 0.25),
                     ),
                     const SizedBox(height: 10),
                     Text(
@@ -627,7 +628,7 @@ class _OpenTabsList extends StatelessWidget {
 
     return ListView.separated(
       itemCount: tabs.length,
-      separatorBuilder: (_, __) => const SizedBox(height: 8),
+      separatorBuilder: (_, _) => const SizedBox(height: 8),
       itemBuilder: (context, index) {
         final tab = tabs[index];
         final selected = tab.id == selectedTabId;
@@ -665,13 +666,13 @@ class _OpenTabsList extends StatelessWidget {
               duration: const Duration(milliseconds: 150),
               decoration: BoxDecoration(
                 color: selected
-                    ? primary.withOpacity(0.14)
+                    ? primary.withValues(alpha: 0.14)
-                    : scheme.onSurface.withOpacity(0.04),
+                    : scheme.onSurface.withValues(alpha: 0.04),
                 borderRadius: BorderRadius.circular(14),
                 border: Border.all(
                   color: selected
-                      ? primary.withOpacity(0.6)
+                      ? primary.withValues(alpha: 0.6)
-                      : scheme.onSurface.withOpacity(0.06),
+                      : scheme.onSurface.withValues(alpha: 0.06),
                   width: selected ? 1.4 : 1,
                 ),
               ),
@@ -764,7 +765,7 @@ class _SelectedTabDetails extends StatelessWidget {
                 Icon(
                   Icons.local_bar_outlined,
                   size: 32,
-                  color: scheme.onSurface.withOpacity(0.25),
+                  color: scheme.onSurface.withValues(alpha: 0.25),
                 ),
                 const SizedBox(height: 8),
                 Text(
@@ -776,7 +777,7 @@ class _SelectedTabDetails extends StatelessWidget {
           )
               : ListView.separated(
             itemCount: tab.items.length,
-            separatorBuilder: (_, __) => const Divider(height: 1),
+            separatorBuilder: (_, _) => const Divider(height: 1),
             itemBuilder: (context, index) {
               final item = tab.items[index];
 
@@ -791,10 +792,10 @@ class _SelectedTabDetails extends StatelessWidget {
         Container(
           padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
           decoration: BoxDecoration(
-            color: Theme.of(context).colorScheme.primary.withOpacity(0.12),
+            color: Theme.of(context).colorScheme.primary.withValues(alpha: 0.12),
             borderRadius: BorderRadius.circular(16),
             border: Border.all(
-              color: Theme.of(context).colorScheme.primary.withOpacity(0.3),
+              color: Theme.of(context).colorScheme.primary.withValues(alpha: 0.3),
             ),
           ),
           child: Row(
@@ -858,7 +859,7 @@ class _TabItemRow extends StatelessWidget {
           ),
           Container(
             decoration: BoxDecoration(
-              color: scheme.onSurface.withOpacity(0.05),
+              color: scheme.onSurface.withValues(alpha: 0.05),
               borderRadius: BorderRadius.circular(999),
             ),
             child: Row(

lib/views/history_screen_view.dart

@@ -118,7 +118,7 @@ class _HistoryScreenViewState extends State<HistoryScreenView> with RouteAware {
                     : ListView.separated(
                   padding: const EdgeInsets.fromLTRB(20, 8, 20, 20),
                   itemCount: viewModel.closedTabs.length,
-                  separatorBuilder: (_, __) => const SizedBox(height: 10),
+                  separatorBuilder: (_, _) => const SizedBox(height: 10),
                   itemBuilder: (context, index) {
                     final closedTab = viewModel.closedTabs[index];
 
@@ -147,12 +147,12 @@ class _EmptyState extends StatelessWidget {
             padding: const EdgeInsets.all(20),
             decoration: BoxDecoration(
               shape: BoxShape.circle,
-              color: scheme.onSurface.withOpacity(0.05),
+              color: scheme.onSurface.withValues(alpha: 0.05),
             ),
             child: Icon(
               Icons.history_rounded,
               size: 40,
-              color: scheme.onSurface.withOpacity(0.3),
+              color: scheme.onSurface.withValues(alpha: 0.3),
             ),
           ),
           const SizedBox(height: 16),
@@ -191,9 +191,9 @@ class _ClosedTabCardState extends State<_ClosedTabCard> {
 
     return Container(
       decoration: BoxDecoration(
-        color: scheme.onSurface.withOpacity(0.04),
+        color: scheme.onSurface.withValues(alpha: 0.04),
         borderRadius: BorderRadius.circular(14),
-        border: Border.all(color: scheme.onSurface.withOpacity(0.06)),
+        border: Border.all(color: scheme.onSurface.withValues(alpha: 0.06)),
       ),
       clipBehavior: Clip.antiAlias,
       child: Material(
@@ -249,7 +249,7 @@ class _ClosedTabCardState extends State<_ClosedTabCard> {
                       _expanded
                           ? Icons.expand_less_rounded
                           : Icons.expand_more_rounded,
-                      color: scheme.onSurface.withOpacity(0.5),
+                      color: scheme.onSurface.withValues(alpha: 0.5),
                     ),
                   ],
                 ),

lib/views/pin_lock_view.dart

@@ -210,7 +210,7 @@ class _PinDots extends StatelessWidget {
             shape: BoxShape.circle,
             color: isFilled ? scheme.primary : Colors.transparent,
             border: Border.all(
-              color: isFilled ? scheme.primary : scheme.onSurface.withOpacity(0.3),
+              color: isFilled ? scheme.primary : scheme.onSurface.withValues(alpha: 0.3),
               width: 1.4,
             ),
           ),
@@ -305,21 +305,21 @@ class _KeypadButton extends StatelessWidget {
       width: 72,
       height: 72,
       child: Material(
-        color: scheme.onSurface.withOpacity(0.04),
+        color: scheme.onSurface.withValues(alpha: 0.04),
         shape: const CircleBorder(),
         child: InkWell(
           customBorder: const CircleBorder(),
           onTap: onTap,
           child: Center(
             child: icon != null
-                ? Icon(icon, color: scheme.onSurface.withOpacity(0.8))
+                ? Icon(icon, color: scheme.onSurface.withValues(alpha: 0.8))
                 : Text(
               label!,
               style: TextStyle(
                 fontSize: 24,
                 fontWeight: FontWeight.w600,
                 color: onTap == null
-                    ? scheme.onSurface.withOpacity(0.3)
+                    ? scheme.onSurface.withValues(alpha: 0.3)
                     : scheme.onSurface,
               ),
             ),

lib/views/product_list_view.dart

@@ -6,9 +6,24 @@ import 'package:provider/provider.dart';
 
 import '../viewmodels/product_list_view_model.dart';
 
-class ProductListView extends StatelessWidget {
+class ProductListView extends StatefulWidget {
   const ProductListView({super.key});
 
+  @override
+  State<ProductListView> createState() => _ProductListViewState();
+}
+
+class _ProductListViewState extends State<ProductListView> {
+
+  @override
+  void initState() {
+    super.initState();
+
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      context.read<ProductListViewModel>().loadProducts();
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     final viewModel = context.watch<ProductListViewModel>();
@@ -53,7 +68,7 @@ class ProductListView extends StatelessWidget {
           return ListView.separated(
             padding: const EdgeInsets.all(16),
             itemCount: viewModel.products.length,
-            separatorBuilder: (_, __) => const SizedBox(height: 8),
+            separatorBuilder: (_, _) => const SizedBox(height: 8),
             itemBuilder: (context, index) {
               final product = viewModel.products[index];
 

lib/views/settings_view.dart

@@ -0,0 +1,345 @@
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+import 'package:provider/provider.dart';
+
+import '../models/settings.dart';
+import '../viewmodels/pin_lock_view_model.dart';
+import '../viewmodels/settings_view_model.dart';
+
+class SettingsScreenView extends StatefulWidget {
+  const SettingsScreenView({super.key});
+
+  @override
+  State<SettingsScreenView> createState() => _SettingsScreenViewState();
+}
+
+class _SettingsScreenViewState extends State<SettingsScreenView> {
+  @override
+  void initState() {
+    super.initState();
+
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      context.read<SettingsViewModel>().ensureLoaded();
+      context.read<PinLockViewModel>().ensureLoaded();
+    });
+  }
+
+  Future<String?> _promptPin(String title, {String hint = 'Enter PIN'}) {
+    final controller = TextEditingController();
+
+    return showDialog<String>(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: Text(title),
+        content: TextField(
+          controller: controller,
+          autofocus: true,
+          obscureText: true,
+          keyboardType: TextInputType.number,
+          maxLength: 6,
+          decoration: InputDecoration(hintText: hint),
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Cancel'),
+          ),
+          FilledButton(
+            onPressed: () => Navigator.pop(context, controller.text),
+            child: const Text('Confirm'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _showError(String message) {
+    if (!mounted) return;
+    ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(message)));
+  }
+
+  Future<void> _enablePin() async {
+    final pin = await _promptPin('Set PIN Code', hint: '4–6 digits');
+    if (pin == null) return;
+
+    if (pin.length < 4) {
+      _showError('PIN must be at least 4 digits');
+      return;
+    }
+
+    final pinLockViewModel = context.read<PinLockViewModel>();
+    final success = await pinLockViewModel.setPin(pin);
+
+    if (!success) {
+      _showError(pinLockViewModel.errorMessage ?? 'Could not set PIN.');
+      return;
+    }
+
+    await context.read<SettingsViewModel>().updatePinRequired(true);
+  }
+
+  Future<void> _changePin() async {
+    final current = await _promptPin('Enter Current PIN');
+    if (current == null) return;
+
+    final newPin = await _promptPin('Enter New PIN', hint: '4–6 digits');
+    if (newPin == null) return;
+
+    if (newPin.length < 4) {
+      _showError('PIN must be at least 4 digits');
+      return;
+    }
+
+    final pinLockViewModel = context.read<PinLockViewModel>();
+    final success = await pinLockViewModel.changePin(
+      currentPin: current,
+      newPin: newPin,
+    );
+
+    if (!success) {
+      _showError(pinLockViewModel.errorMessage ?? 'Could not change PIN.');
+    }
+  }
+
+  Future<void> _disablePin() async {
+    final current = await _promptPin('Enter Current PIN to Disable');
+    if (current == null) return;
+
+    final pinLockViewModel = context.read<PinLockViewModel>();
+    final success = await pinLockViewModel.disablePin(current);
+
+    if (!success) {
+      _showError(pinLockViewModel.errorMessage ?? 'Could not disable PIN.');
+      return;
+    }
+
+    await context.read<SettingsViewModel>().updatePinRequired(false);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final settingsViewModel = context.watch<SettingsViewModel>();
+    final pinLockViewModel = context.watch<PinLockViewModel>();
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Row(
+          children: [
+            IconButton(
+              onPressed: () => context.go('/bar'),
+              icon: const Icon(Icons.arrow_back),
+            ),
+            const SizedBox(width: 5),
+            const Text('Settings'),
+          ],
+        ),
+      ),
+      body: Builder(
+        builder: (context) {
+          final isLoading = settingsViewModel.isLoading || pinLockViewModel.isLoading;
+          final hasLoaded = settingsViewModel.hasLoaded && pinLockViewModel.hasLoaded;
+
+          if (isLoading && !hasLoaded) {
+            return const Center(
+              child: CircularProgressIndicator(strokeWidth: 2.5),
+            );
+          }
+
+          final settings = settingsViewModel.settings;
+
+          return ListView(
+            padding: const EdgeInsets.symmetric(vertical: 12),
+            children: [
+              _SettingsSection(
+                title: 'Security',
+                children: [
+                  _SettingsSwitchTile(
+                    icon: Icons.lock_outline_rounded,
+                    title: 'PIN Required',
+                    value: settings.pinRequired,
+                    onChanged: (value) {
+                      if (value) {
+                        _enablePin();
+                      } else {
+                        _disablePin();
+                      }
+                    },
+                  ),
+                  if (settings.pinRequired)
+                    _SettingsTile(
+                      icon: Icons.pin_rounded,
+                      title: 'Change PIN',
+                      onTap: _changePin,
+                    ),
+                ],
+              ),
+              _SettingsSection(
+                title: 'Appearance',
+                children: [
+                  _SettingsTile(
+                    icon: Icons.brightness_6_rounded,
+                    title: 'Theme',
+                    subtitle: switch (settings.themeMode) {
+                      AppThemeMode.system => 'System',
+                      AppThemeMode.light => 'Light',
+                      AppThemeMode.dark => 'Dark',
+                    },
+                    onTap: () async {
+                      final selected = await showModalBottomSheet<AppThemeMode>(
+                        context: context,
+                        builder: (context) => SafeArea(
+                          child: Column(
+                            mainAxisSize: MainAxisSize.min,
+                            children: AppThemeMode.values.map((mode) {
+                              return RadioListTile<AppThemeMode>(
+                                value: mode,
+                                groupValue: settings.themeMode,
+                                title: Text(switch (mode) {
+                                  AppThemeMode.system => 'System',
+                                  AppThemeMode.light => 'Light',
+                                  AppThemeMode.dark => 'Dark',
+                                }),
+                                onChanged: (value) => Navigator.pop(context, value),
+                              );
+                            }).toList(),
+                          ),
+                        ),
+                      );
+
+                      if (selected != null) {
+                        await settingsViewModel.updateThemeMode(selected);
+                      }
+                    },
+                  ),
+                ],
+              ),
+            ],
+          );
+        },
+      ),
+    );
+  }
+}
+
+class _SettingsSection extends StatelessWidget {
+  final String title;
+  final List<Widget> children;
+
+  const _SettingsSection({required this.title, required this.children});
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 8),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            title.toUpperCase(),
+            style: TextStyle(
+              fontSize: 12,
+              fontWeight: FontWeight.w700,
+              letterSpacing: 0.5,
+              color: scheme.onSurface.withValues(alpha: 0.5),
+            ),
+          ),
+          const SizedBox(height: 8),
+          Container(
+            decoration: BoxDecoration(
+              color: scheme.onSurface.withValues(alpha: 0.04),
+              borderRadius: BorderRadius.circular(14),
+              border: Border.all(color: scheme.onSurface.withValues(alpha: 0.06)),
+            ),
+            clipBehavior: Clip.antiAlias,
+            child: Column(children: children),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class _SettingsTile extends StatelessWidget {
+  final IconData icon;
+  final String title;
+  final String? subtitle;
+  final VoidCallback? onTap;
+
+  const _SettingsTile({
+    required this.icon,
+    required this.title,
+    this.subtitle,
+    this.onTap,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+
+    return Material(
+      color: Colors.transparent,
+      child: InkWell(
+        onTap: onTap,
+        child: Padding(
+          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+          child: Row(
+            children: [
+              Icon(icon, size: 22, color: scheme.onSurface.withValues(alpha: 0.7)),
+              const SizedBox(width: 14),
+              Expanded(
+                child: Text(
+                  title,
+                  style: TextStyle(fontWeight: FontWeight.w600, color: scheme.onSurface),
+                ),
+              ),
+              if (subtitle != null) ...[
+                Text(subtitle!, style: Theme.of(context).textTheme.bodySmall),
+                const SizedBox(width: 4),
+              ],
+              if (onTap != null)
+                Icon(Icons.chevron_right_rounded, color: scheme.onSurface.withValues(alpha: 0.3)),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class _SettingsSwitchTile extends StatelessWidget {
+  final IconData icon;
+  final String title;
+  final bool value;
+  final ValueChanged<bool> onChanged;
+
+  const _SettingsSwitchTile({
+    required this.icon,
+    required this.title,
+    required this.value,
+    required this.onChanged,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
+      child: Row(
+        children: [
+          Icon(icon, size: 22, color: scheme.onSurface.withValues(alpha: 0.7)),
+          const SizedBox(width: 14),
+          Expanded(
+            child: Text(
+              title,
+              style: TextStyle(fontWeight: FontWeight.w600, color: scheme.onSurface),
+            ),
+          ),
+          Switch(value: value, onChanged: onChanged),
+        ],
+      ),
+    );
+  }
+}

pubspec.yaml

@@ -46,6 +46,10 @@ dependencies:
   intl: ^0.20.3
   flutter_secure_storage: ^9.0.0
   crypto: ^3.0.0
+#  http: ^1.6.0
+#  package_info_plus: ^10.2.1
+#  open_filex: ^4.7.0
+#  permission_handler: ^12.0.3
 
 
 dev_dependencies:

test/widget_test.dart

@@ -5,10 +5,7 @@
 // gestures. You can also use WidgetTester to find child widgets in the widget
 // tree, read text, and verify that the values of widget properties are correct.
 
-import 'package:flutter/material.dart';
-import 'package:flutter_test/flutter_test.dart';
 
-import 'package:kooltab2/main.dart';
 
 void main() {
 }