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

import 'core/providers/biometric_provider.dart';
import 'core/providers/model_download_provider.dart';
import 'core/providers/settings_provider.dart';
import 'core/providers/theme_provider.dart';
import 'features/model_download/model_download_screen.dart';
import 'shell.dart';

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

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final skipped = ref.watch(modelSkippedProvider);
    final modelPresentAsync = ref.watch(modelPresentProvider);
    final themeModeAsync = ref.watch(themeModeProvider);
    final biometricEnabled =
        ref.watch(settingProvider(SettingsKeys.biometricEnabled));
    final biometricUnlocked = ref.watch(biometricUnlockedProvider);

    final themeMode = themeModeAsync.value ?? ThemeMode.system;

    Widget mainContent() {
      if (biometricEnabled.value == 'true' && !biometricUnlocked) {
        return const _BiometricLockScreen();
      }
      return const AppShell();
    }

    return MaterialApp(
      title: 'DailyYou',
      debugShowCheckedModeBanner: false,
      theme: _lightTheme(),
      darkTheme: _darkTheme(),
      themeMode: themeMode,
      home: skipped
          ? mainContent()
          : modelPresentAsync.when(
              data: (present) =>
                  present ? mainContent() : const ModelDownloadScreen(),
              loading: () => const Scaffold(
                body: Center(child: CircularProgressIndicator()),
              ),
              error: (_, __) => const ModelDownloadScreen(),
            ),
    );
  }

  ThemeData _lightTheme() => ThemeData(
        useMaterial3: true,
        colorScheme: ColorScheme.fromSeed(
          seedColor: const Color(0xFF6B8CFF),
          brightness: Brightness.light,
        ),
      );

  ThemeData _darkTheme() => ThemeData(
        useMaterial3: true,
        colorScheme: ColorScheme.fromSeed(
          seedColor: const Color(0xFF6B8CFF),
          brightness: Brightness.dark,
        ),
      );
}

class _BiometricLockScreen extends ConsumerStatefulWidget {
  const _BiometricLockScreen();

  @override
  ConsumerState<_BiometricLockScreen> createState() =>
      _BiometricLockScreenState();
}

class _BiometricLockScreenState extends ConsumerState<_BiometricLockScreen> {
  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      ref.read(biometricUnlockedProvider.notifier).tryUnlock();
    });
  }

  @override
  Widget build(BuildContext context) {
    final cs = Theme.of(context).colorScheme;
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(Icons.lock_outline, size: 64, color: cs.primary),
            const SizedBox(height: 24),
            Text('DailyYou is locked',
                style: Theme.of(context).textTheme.titleLarge),
            const SizedBox(height: 16),
            FilledButton.icon(
              onPressed: () =>
                  ref.read(biometricUnlockedProvider.notifier).tryUnlock(),
              icon: const Icon(Icons.fingerprint),
              label: const Text('Unlock'),
            ),
          ],
        ),
      ),
    );
  }
}