import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:hl_lieferservice/bloc/app_bloc.dart';
import 'package:hl_lieferservice/data/network/keycloak_oidc_token_provider.dart';
import 'package:hl_lieferservice/feature/authentication/bloc/auth_bloc.dart';
import 'package:hl_lieferservice/feature/authentication/bloc/auth_event.dart';
import 'package:hl_lieferservice/feature/authentication/presentation/login_enforcer.dart';
import 'package:hl_lieferservice/main.dart' show locator;
import 'package:hl_lieferservice/feature/car_selection/presentation/car_selection_enforcer.dart';
import 'package:hl_lieferservice/feature/cars/presentation/car_management_page.dart';
import 'package:hl_lieferservice/data/repository/payment_methods_repository_impl.dart';
import 'package:hl_lieferservice/feature/payment_methods/bloc/payment_methods_cubit.dart';
import 'package:holzleitner_api/holzleitner_api.dart' show HolzleitnerApi;
import 'package:hl_lieferservice/feature/feature_flags/feature_flags.dart';
import 'package:hl_lieferservice/widget/home/bloc/navigation_bloc.dart';
import 'package:hl_lieferservice/widget/operations/bloc/operation_bloc.dart';
import 'package:hl_lieferservice/widget/operations/presentation/operation_view_enforcer.dart';
import 'package:hl_lieferservice/widget/session_scope.dart';

import 'package:hl_lieferservice/bloc/app_states.dart';
import 'home/presentation/home.dart';

class DeliveryApp extends StatefulWidget {
  const DeliveryApp({super.key});

  @override
  State<StatefulWidget> createState() => _DeliveryAppState();
}

class _DeliveryAppState extends State<DeliveryApp> {
  @override
  Widget build(BuildContext context) {
    return BlocBuilder<AppBloc, AppState>(
      builder: (context, state) {
        if (state is AppConfigLoaded) {
          return MultiBlocProvider(
            // Pro Server-Umgebung ein eigener Baum: Beim Wechsel entstehen
            // alle Blocs neu und holen sich den frisch registrierten
            // API-Client. Kein Bloc hält Daten der alten Umgebung.
            key: ValueKey('environment-${state.active.id}'),
            providers: [
              // Feature-Schalter aus `assets/feature_flags.json`; Widgets lesen
              // sie über `FeatureGate` bzw. `context.read<FeatureFlags>()`.
              RepositoryProvider<FeatureFlags>.value(value: state.featureFlags),
              BlocProvider(create: (context) => NavigationBloc()),
              BlocProvider(create: (context) => OperationBloc()),
              BlocProvider(
                create:
                    (context) => AuthBloc(
                          tokenProvider:
                              locator<KeycloakOidcTokenProvider>(),
                          operationBloc: context.read<OperationBloc>(),
                        )
                        // Beim ersten Build: prüfen, ob ein
                        // Refresh-Token aus der Secure Storage da ist,
                        // und ggf. direkt einloggen.
                        ..add(const RestoreSessionRequested()),
              ),
              BlocProvider(
                // Zahlungsmethoden sind firmenweite Stammdaten — wir laden
                // sie einmal beim App-Start und cachen sie im Cubit. Der
                // Detail-Screen einer Lieferung greift darauf zu, um den
                // `paymentMethodId`-FK auf einen lesbaren Namen aufzulösen.
                create: (context) => PaymentMethodsCubit(
                  repository:
                      PaymentMethodsRepositoryImpl(locator<HolzleitnerApi>()),
                )..load(),
              ),
            ],
            // Fahrerbezogene Blocs (Tour, Fahrzeuge, Auswahl, Phase) je
            // Anmeldung neu — siehe SessionScope.
            child: SessionScope(
              environmentId: state.active.id,
                child: MaterialApp(
                title: 'Holzleitner Auslieferung',
                debugShowCheckedModeBanner: false,
                // Wrap the Navigator (not just the home route) so the loading
                // overlay covers every pushed route — DeliveryDetail, Cars,
                // dialogs, etc. — not only the initial home tree.
                builder: (context, child) =>
                    OperationViewEnforcer(child: child ?? const SizedBox.shrink()),
                home: BlocBuilder<AppBloc, AppState>(
                  builder: (context, state) {
                    if (state is AppConfigLoading) {
                      return Scaffold(
                        body: Center(child: CircularProgressIndicator()),
                      );
                    }

                    if (state is AppConfigLoadingFailed) {
                      return Scaffold(body: Center(child: Text(state.message)));
                    }

                    if (state is AppConfigLoaded) {
                      // Zahlungsmethoden lädt SessionScope nach jeder Anmeldung neu.
                      return LoginEnforcer(
                        child: CarSelectionEnforcer(child: Home()),
                      );
                    }

                    return Container();
                  },
                ),
                routes: {"/cars": (context) => CarManagementPage()},
              ),
            ),
          );
        }

        if (state is AppConfigLoadingFailed) {
          return MaterialApp(
            title: 'Holzleitner Auslieferung',
            debugShowCheckedModeBanner: false,
            home: Scaffold(
              body: Center(
                child: Padding(
                  padding: const EdgeInsets.all(24),
                  child: Text(state.message, textAlign: TextAlign.center),
                ),
              ),
            ),
          );
        }

        return MaterialApp(
          title: 'Holzleitner Auslieferung',
          debugShowCheckedModeBanner: false,
          home: Scaffold(
            body: Center(child: const CircularProgressIndicator()),
          ),
        );
      },
    );
  }
}