import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:worldhopper/l10n/app_localizations.dart';
import 'package:worldhopper/helpers/snackbar_helper.dart';
import 'package:worldhopper/providers/download_provider.dart';
import 'package:worldhopper/screens/settings/about_screen.dart';
import 'package:worldhopper/screens/settings/advanced_settings_screen.dart';
import 'package:worldhopper/screens/settings/appearance_settings_screen.dart';
import 'package:worldhopper/screens/settings/language_settings_screen.dart';
import 'package:worldhopper/screens/settings/readers_settings_screen.dart';
import 'package:worldhopper/widgets/worldhopper_app_bar.dart';

/// Screen for app settings and configuration
class SettingsScreen extends ConsumerWidget {
  const SettingsScreen({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final l10n = AppLocalizations.of(context);

    return Scaffold(
      appBar: WorldhopperAppBar(
        title: Text(l10n.settingsTitle),
      ),
      body: ListView(
        children: [
          const SizedBox(height: 8),
          Card(
            margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
            child: Column(
              children: [
                ListTile(
                  leading: const Icon(Icons.palette_outlined),
                  title: Text(l10n.settingsAppearance),
                  subtitle: Text(l10n.settingsAppearanceSubtitle),
                  trailing: const Icon(Icons.chevron_right),
                  onTap: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => const AppearanceSettingsScreen(),
                      ),
                    );
                  },
                ),
                const Divider(height: 1),
                ListTile(
                  leading: const Icon(Icons.language_outlined),
                  title: Text(l10n.settingsLanguage),
                  subtitle: Text(l10n.settingsLanguageSubtitle),
                  trailing: const Icon(Icons.chevron_right),
                  onTap: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => const LanguageSettingsScreen(),
                      ),
                    );
                  },
                ),
                const Divider(height: 1),
                ListTile(
                  leading: const Icon(Icons.menu_book_outlined),
                  title: Text(l10n.settingsReaders),
                  subtitle: Text(l10n.settingsReadersSubtitle),
                  trailing: const Icon(Icons.chevron_right),
                  onTap: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => const ReadersSettingsScreen(),
                      ),
                    );
                  },
                ),
                const Divider(height: 1),
                ListTile(
                  leading: const Icon(Icons.tune_outlined),
                  title: Text(l10n.settingsAdvanced),
                  subtitle: Text(l10n.settingsAdvancedSubtitle),
                  trailing: const Icon(Icons.chevron_right),
                  onTap: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => const AdvancedSettingsScreen(),
                      ),
                    );
                  },
                ),
                const Divider(height: 1),
                ListTile(
                  leading: const Icon(Icons.info_outline),
                  title: Text(l10n.settingsAbout),
                  subtitle: Text(l10n.settingsAboutSubtitle),
                  trailing: const Icon(Icons.chevron_right),
                  onTap: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => const AboutScreen(),
                      ),
                    );
                  },
                ),
              ],
            ),
          ),
          const SizedBox(height: 8),
          _DownloadStorageCard(),
          const SizedBox(height: 16),
        ],
      ),
    );
  }
}

class _DownloadStorageCard extends ConsumerWidget {
  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return Card(
      margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
      child: Column(
        children: [
          _DownloadStorageTile(
            onTap: () => _confirmClearDownloads(context, ref),
          ),
        ],
      ),
    );
  }

  Future<void> _confirmClearDownloads(
      BuildContext context, WidgetRef ref) async {
    final l10n = AppLocalizations.of(context);
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(l10n.settingsClearAllDownloads),
        content: Text(l10n.settingsClearAllDownloadsConfirmation),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(false),
            child: Text(l10n.commonCancel),
          ),
          FilledButton(
            onPressed: () => Navigator.of(context).pop(true),
            style: FilledButton.styleFrom(
              backgroundColor: Theme.of(context).colorScheme.error,
            ),
            child: Text(l10n.commonDelete),
          ),
        ],
      ),
    );

    if (confirmed == true && context.mounted) {
      final notifier = ref.read(downloadNotifierProvider.notifier);
      final seriesRepo = ref.read(downloadedSeriesRepositoryProvider);
      final allSeries = await seriesRepo.getAll();
      for (final series in allSeries) {
        await notifier.deleteSeries(series.id);
      }
      if (context.mounted) {
        context.showInfoSnackBar(l10n.settingsDownloadsCleared);
      }
    }
  }

  static String _formatBytes(int bytes) {
    if (bytes < 1024) return '$bytes B';
    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
    if (bytes < 1024 * 1024 * 1024) {
      return '${(bytes / (1024 * 1024)).toStringAsFixed(1)} MB';
    }
    return '${(bytes / (1024 * 1024 * 1024)).toStringAsFixed(1)} GB';
  }
}

class _DownloadStorageTile extends ConsumerStatefulWidget {
  final VoidCallback onTap;

  const _DownloadStorageTile({required this.onTap});

  @override
  ConsumerState<_DownloadStorageTile> createState() =>
      _DownloadStorageTileState();
}

class _DownloadStorageTileState extends ConsumerState<_DownloadStorageTile> {
  Future<int>? _sizeFuture;

  @override
  void initState() {
    super.initState();
    _sizeFuture =
        ref.read(downloadStorageServiceProvider).getTotalDownloadSize();
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);

    return ListTile(
      leading: const Icon(Icons.download_outlined),
      title: Text(l10n.settingsDownloadedContent),
      subtitle: FutureBuilder<int>(
        future: _sizeFuture,
        builder: (context, snapshot) {
          if (snapshot.hasData) {
            return Text(l10n.settingsDownloadSize(
                _DownloadStorageCard._formatBytes(snapshot.data!)));
          }
          return Text(l10n.settingsDownloadedContentSubtitle);
        },
      ),
      trailing: const Icon(Icons.chevron_right),
      onTap: widget.onTap,
    );
  }
}