import 'package:flutter_test/flutter_test.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:travel_mate/models/budget_category.dart';
import 'package:travel_mate/services/budget_service.dart';

void main() {
  const tripId = 'trip-budget-1';
  late BudgetService service;

  setUp(() {
    SharedPreferences.setMockInitialValues({});
    service = BudgetService();
  });

  test('adds and deletes budget envelopes', () async {
    final cat = BudgetCategory.newCategory(
      id: 'food',
      name: 'Food',
      planned: 300,
      currency: 'EUR',
    );
    await service.addBudget(tripId, cat);

    var loaded = await service.loadBudgets(tripId);
    expect(loaded.single.name, 'Food');

    loaded = await service.deleteBudget(tripId, 'food');
    expect(loaded, isEmpty);
  });

  test('updates spent amount', () async {
    final cat = BudgetCategory.newCategory(
      id: 'transport',
      name: 'Transport',
      planned: 200,
      currency: 'USD',
    );
    await service.addBudget(tripId, cat);

    final updated = await service.updateSpent(tripId, 'transport', 55.5);
    expect(updated.first.spent, 55.5);
  });

  test('corrupted payload cleared', () async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.setString('budget_$tripId', 'oops');
    final loaded = await service.loadBudgets(tripId);
    expect(loaded, isEmpty);
    expect(prefs.getString('budget_$tripId'), isNull);
  });
}