import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:google_fonts/google_fonts.dart';
import 'package:nearle_pos/app/app.dart';
import 'package:nearle_pos/data/datasources/local_store.dart';
import 'package:nearle_pos/data/datasources/seed_data.dart';
import 'package:nearle_pos/app/providers.dart';
import 'package:nearle_pos/domain/entities/shift_report.dart';
import 'package:nearle_pos/domain/entities/store_account.dart';
import 'package:nearle_pos/presentation/auth/providers/auth_controller.dart';
import 'package:nearle_pos/presentation/pos/providers/cart_controller.dart';
import 'package:nearle_pos/presentation/pos/screens/pos_dashboard_screen.dart';
import 'package:nearle_pos/presentation/sync/providers/sync_controller.dart';

/// Boots the real application widget.
///
/// The unit suite proves the money is right; this proves the thing actually
/// assembles — router guard, provider graph, theme and shell — which type
/// checking alone cannot tell you.
void main() {
  setUpAll(() {
    // Tests have no network, and an attempted font fetch throws.
    GoogleFonts.config.allowRuntimeFetching = false;
    LocalStore.registerSeed(
      products: SeedData.products,
      customers: SeedData.customers,
    );
  });

  setUp(() async {
    await LocalStore.instance.reset(withCatalogue: true);
  });

  const testStore = StoreAccount(
    id: 'store-001',
    name: 'Nearle Daily',
    email: DemoCredentials.email,
    address: '1 Test Street',
    gstin: '33AABCU9603R1ZM',
    phone: '9840000000',
    staff: [
      StaffUser(id: 'u1', name: 'Suriya', role: StaffRole.admin),
    ],
  );

  ShiftReport blankReport() => ShiftReport.blank(
        businessDate: DateTime(2026, 7, 31),
        terminalId: 'TERM-01',
        cashierName: 'Suriya',
      );

  Future<void> bootApp(WidgetTester tester) async {
    await tester.pumpWidget(
      ProviderScope(
        overrides: [
          // The background drain would open a broker connection and hit the
          // disk on a clock this test controls. Neither is what these tests
          // measure, and a half-driven timer would leak into the next one.
          syncBootstrapProvider.overrideWith((ref) async {}),

          // Sign-in now reads staff and store details from SQLite. Real disk
          // I/O cannot complete inside a fixed number of pumps on a fake
          // clock, so the sign-in would hang and every later assertion would
          // fail on a screen that never arrived.
          storeAccountProvider.overrideWith((ref) async => testStore),

          // Catalogue reads come from the in-memory cache and resolve on the
          // spot, but these four go to SQLite. Real disk I/O cannot be driven
          // by the fake clock a widget test runs on: sqflite's own lock-warning
          // timer is left pending and trips the binding's leak check. Stubbed
          // so this test measures rendering, which is what it is for.
          unsyncedCountProvider.overrideWith((ref) async => 0),
          parkedBillsProvider.overrideWith((ref) async => []),
          orderSyncRowsProvider.overrideWith((ref) async => []),
          todayReportProvider.overrideWith((ref) async => blankReport()),
          myShiftReportProvider.overrideWith((ref) async => blankReport()),
        ],
        child: const NearlePosApp(),
      ),
    );
    await tester.pumpAndSettle();
  }

  /// Pumps a fixed number of frames instead of settling.
  ///
  /// Once past login the header subscribes to a periodic clock, so there is
  /// always another frame pending and `pumpAndSettle` never returns.
  Future<void> settle(WidgetTester tester, {int frames = 15}) async {
    for (var i = 0; i < frames; i++) {
      await tester.pump(const Duration(milliseconds: 100));
    }
  }

  Future<void> signIn(WidgetTester tester) async {
    final fields = find.byType(TextFormField);
    await tester.enterText(fields.first, DemoCredentials.email);
    await tester.enterText(fields.at(1), DemoCredentials.password);
    await tester.pump();

    await tester.tap(find.text('Sign in').last);
    await settle(tester);
  }

  testWidgets('the terminal starts on the login screen', (tester) async {
    await bootApp(tester);

    expect(find.byType(TextFormField), findsWidgets);
    expect(find.text('Sign in'), findsWidgets);
    expect(tester.takeException(), isNull);
  });

  testWidgets('the auth guard keeps an unauthenticated terminal out',
      (tester) async {
    await bootApp(tester);

    expect(find.byType(PosDashboardScreen), findsNothing);
  });

  testWidgets('signing in reaches the billing terminal', (tester) async {
    await bootApp(tester);
    await signIn(tester);

    expect(find.byType(PosDashboardScreen), findsOneWidget);
    expect(tester.takeException(), isNull);
  });

  testWidgets('the shell renders every module without throwing',
      (tester) async {
    // Wide enough that the sidebar shows labels and the bill stays docked —
    // the layout where a button label and its total compete for width.
    tester.view.physicalSize = const Size(1800, 1200);
    tester.view.devicePixelRatio = 1;
    addTearDown(tester.view.reset);

    await bootApp(tester);
    await signIn(tester);

    for (final label in [
      'Customers',
      'Product Import',
      'Promo',
      'Events',
      'Settings',
      'POS',
    ]) {
      final target = find.text(label);
      expect(target, findsWidgets, reason: 'no sidebar entry for "$label"');

      await tester.tap(target.first);
      await settle(tester);
      expect(tester.takeException(), isNull, reason: 'opening "$label" threw');
    }
  });

  testWidgets('the back office connection dialog opens and validates',
      (tester) async {
    // The only way a shop can point a till at a broker. Until it existed a
    // store was wired up by editing a provider and rebuilding.
    tester.view.physicalSize = const Size(1800, 1200);
    tester.view.devicePixelRatio = 1;
    addTearDown(tester.view.reset);

    await bootApp(tester);
    await signIn(tester);

    await tester.tap(find.text('Settings').first);
    await settle(tester);

    await tester.tap(find.text('Configure').first);
    await settle(tester);

    // "Back office connection" is both the dialog title and the About card's
    // button, so match the dialog itself.
    expect(find.byType(AlertDialog), findsOneWidget);
    expect(find.text('MQTT'), findsOneWidget);

    // Switching to MQTT and saving with no host must be refused, not silently
    // accepted — a terminal pointed at nothing looks identical to one that is
    // simply offline.
    await tester.tap(find.text('MQTT'));
    await settle(tester);
    await tester.tap(find.text('Save'));
    await settle(tester);

    expect(find.text('A broker host is required'), findsOneWidget);
    expect(find.byType(AlertDialog), findsOneWidget,
        reason: 'the dialog must stay open on a validation failure',);
    expect(tester.takeException(), isNull);
  });
}