import 'package:flutter/material.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:pyramid/core/app_state.dart';
import 'package:pyramid/core/notification_service.dart' show checkPendingReply, setAppForeground;
import 'package:pyramid/core/router.dart';
import 'package:pyramid/core/settings_prefs.dart';
import 'package:pyramid/core/theme.dart';
import 'package:pyramid/features/auth/login_notifier.dart';
import 'package:pyramid/widgets/pyramid_loader.dart';

class PyramidApp extends ConsumerStatefulWidget {
  const PyramidApp({super.key});

  @override
  ConsumerState<PyramidApp> createState() => _PyramidAppState();
}

class _PyramidAppState extends ConsumerState<PyramidApp>
    with WidgetsBindingObserver {
  bool _prefsLoaded = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    _loadPersistedPrefs();
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    switch (state) {
      case AppLifecycleState.resumed:
        setAppForeground(true);
        checkPendingReply(ref);
      case AppLifecycleState.paused:
      case AppLifecycleState.detached:
        // Clears heartbeat so PushService.kt shows FCM notifications immediately.
        // Background Matrix syncs must not re-set the heartbeat (see notification_service.dart).
        setAppForeground(false);
      default:
        break;
    }
  }

  Future<void> _loadPersistedPrefs() async {
    final saved = await loadThemePrefs();
    if (!mounted) return;
    ref.read(themeModeProvider.notifier).state = saved.isDark;
    ref.read(accentProvider.notifier).state = saved.accentIdx;
    ref.read(radiusProvider.notifier).state = saved.radius;
    ref.read(motionProvider.notifier).state = saved.motion;
    setState(() => _prefsLoaded = true);
  }

  @override
  Widget build(BuildContext context) {
    // Block the router from rendering until auth state is known so the
    // /server page never flashes before the redirect to /app fires.
    final authAsync = ref.watch(isLoggedInProvider);
    if (authAsync.isLoading || !_prefsLoaded) {
      return const MaterialApp(
        debugShowCheckedModeBanner: false,
        home: Scaffold(
          backgroundColor: Color(0xFF1A1B1E),
          body: Center(child: PyramidLoader(size: 80)),
        ),
      );
    }

    final router = ref.watch(routerProvider);
    final isDark = ref.watch(themeModeProvider);
    final accentIdx = ref.watch(accentProvider);
    final radius = ref.watch(radiusProvider);
    final density = ref.watch(densityProvider);
    final motion = ref.watch(motionProvider);
    final accent = accentPresets[accentIdx].color;

    return PyramidTheme(
      isDark: isDark,
      accent: accent,
      radius: radius,
      density: density,
      motion: motion,
      child: MaterialApp.router(
        title: 'Pyramid',
        theme: buildPyramidThemeData(false),
        darkTheme: buildPyramidThemeData(true),
        themeMode: isDark ? ThemeMode.dark : ThemeMode.light,
        routerConfig: router,
        localizationsDelegates: const [
          GlobalMaterialLocalizations.delegate,
          GlobalWidgetsLocalizations.delegate,
          GlobalCupertinoLocalizations.delegate,
        ],
        supportedLocales: const [Locale('de'), Locale('en')],
        debugShowCheckedModeBanner: false,
      ),
    );
  }
}