fix: alot

test/closed_tab_model_test.dart

@@ -0,0 +1,87 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:kooltap/models/closed_tab.dart';
+import 'package:kooltap/models/closed_tab_item.dart';
+import 'package:kooltap/models/payment_method.dart';
+
+ClosedTabItem _item({
+  required String id,
+  int quantity = 1,
+  int unitPriceInCents = 400,
+  DateTime? removedAt,
+}) {
+  return ClosedTabItem(
+    id: id,
+    closedTabId: 'closed-1',
+    productId: 'prod-1',
+    productName: 'Beer',
+    quantity: quantity,
+    unitPriceInCents: unitPriceInCents,
+    purchasedAt: DateTime(2026, 1, 1, 20),
+    removedAt: removedAt,
+  );
+}
+
+ClosedTab _tab(List<ClosedTabItem> items) {
+  return ClosedTab(
+    id: 'closed-1',
+    originalTabId: 'tab-1',
+    customerName: 'John',
+    closedAt: DateTime(2026, 1, 1, 23),
+    paymentMethod: PaymentMethod.cash,
+    items: items,
+  );
+}
+
+void main() {
+  group('ClosedTabItem', () {
+    test('charges quantity times unit price', () {
+      expect(
+        _item(id: 'a', quantity: 3, unitPriceInCents: 250).lineTotalInCents,
+        750,
+      );
+    });
+
+    test('charges nothing once removed', () {
+      final removed = _item(id: 'a', removedAt: DateTime(2026, 1, 1, 21));
+
+      expect(removed.isRemoved, true);
+      expect(removed.lineTotalInCents, 0);
+    });
+  });
+
+  group('ClosedTab', () {
+    test('totals only the purchases that were not removed', () {
+      final tab = _tab([
+        _item(id: 'a', unitPriceInCents: 400),
+        _item(id: 'b', unitPriceInCents: 400),
+        _item(id: 'c', unitPriceInCents: 600),
+        _item(id: 'd', unitPriceInCents: 400, removedAt: DateTime(2026)),
+      ]);
+
+      expect(tab.totalInCents, 1400);
+      expect(tab.itemCount, 3);
+    });
+
+    test('is zero when every purchase was removed', () {
+      final tab = _tab([
+        _item(id: 'a', removedAt: DateTime(2026)),
+        _item(id: 'b', removedAt: DateTime(2026)),
+      ]);
+
+      expect(tab.totalInCents, 0);
+      expect(tab.itemCount, 0);
+    });
+  });
+
+  group('PaymentMethod', () {
+    test('round-trips through its stored value', () {
+      for (final method in PaymentMethod.values) {
+        expect(PaymentMethod.fromValue(method.value), method);
+      }
+    });
+
+    test('falls back to cash for an unknown value', () {
+      expect(PaymentMethod.fromValue('bitcoin'), PaymentMethod.cash);
+    });
+  });
+}