import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import 'core/firebase/firebase_providers.dart';
import 'core/router/app_router.dart';
import 'core/settings/settings_provider.dart';
import 'core/theme/app_theme.dart';
import 'features/notifications/data/push_registration_service.dart';
import 'l10n/generated/app_localizations.dart';

class LeafItToMeApp extends ConsumerWidget {
  const LeafItToMeApp({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final settings = ref.watch(settingsProvider);
    final router = ref.watch(appRouterProvider);

    // Nach jedem Login das Gerät für Push-Erinnerungen registrieren.
    ref.listen(authStateProvider, (previous, next) {
      final user = next.value;
      if (user != null) {
        ref.read(pushRegistrationServiceProvider).registerDevice(user);
      }
    });

    return MaterialApp.router(
      routerConfig: router,
      onGenerateTitle: (context) => AppLocalizations.of(context).appTitle,
      theme: buildAppTheme(
        brightness: Brightness.light,
        highContrast: settings.highContrast,
      ),
      darkTheme: buildAppTheme(
        brightness: Brightness.dark,
        highContrast: settings.highContrast,
      ),
      themeMode: settings.themeMode,
      localizationsDelegates: AppLocalizations.localizationsDelegates,
      supportedLocales: AppLocalizations.supportedLocales,
      builder: (context, child) {
        // App-Schriftgröße wird ZUSÄTZLICH zur System-Schriftgröße angewendet,
        // damit die Systemeinstellung des Nutzers respektiert bleibt.
        final systemScale = MediaQuery.textScalerOf(context).scale(1.0);
        return MediaQuery(
          data: MediaQuery.of(context).copyWith(
            textScaler: TextScaler.linear(systemScale * settings.textSize.factor),
          ),
          child: child!,
        );
      },
    );
  }
}