import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../models/home_config.dart';
import '../providers/providers.dart';
import '../widgets/build_info_text.dart';
import 'home_edit_screen.dart';
import 'remote_screen.dart';

/// Экран "Дома" -- список серверов Ignis.
/// Пользователь может добавить, удалить, переключить активный дом.
class HomesScreen extends ConsumerStatefulWidget {
  const HomesScreen({super.key});

  @override
  ConsumerState<HomesScreen> createState() => _HomesScreenState();
}

class _HomesScreenState extends ConsumerState<HomesScreen> {
  late final UserLocationNotifier _userLocationNotifier;

  @override
  void initState() {
    super.initState();
    _userLocationNotifier = ref.read(userLocationProvider.notifier);
    Future.microtask(() => _userLocationNotifier.startWatching());
  }

  @override
  void dispose() {
    _userLocationNotifier.stopWatching();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final homes = ref.watch(homesProvider);
    final currentHome = ref.watch(currentHomeProvider);
    final location = ref.watch(userLocationProvider);

    return Scaffold(
      appBar: AppBar(
        title: const Text('ДОМА'),
        automaticallyImplyLeading: false,
      ),
      body: Column(
        children: [
          Expanded(
            child: homes.isEmpty
                ? const _EmptyHomesView()
                : ListView.builder(
                    padding: const EdgeInsets.all(12),
                    itemCount: homes.length,
                    itemBuilder: (context, index) {
                      final home = homes[index];
                      final isActive = currentHome?.id == home.id;
                      final distKm = location.distanceToKm(
                        home.latitude,
                        home.longitude,
                      );

                      return Card(
                        margin: const EdgeInsets.only(bottom: 8),
                        child: ListTile(
                          leading: Icon(
                            Icons.home,
                            color: isActive
                                ? Colors.deepOrange
                                : Colors.white38,
                            size: 28,
                          ),
                          title: Text(
                            home.name,
                            style: TextStyle(
                              fontWeight: isActive
                                  ? FontWeight.bold
                                  : FontWeight.normal,
                              color: isActive
                                  ? Colors.deepOrange
                                  : Colors.white,
                            ),
                          ),
                          subtitle: _HomeSubtitle(
                            home: home,
                            location: location,
                            distKm: distKm,
                          ),
                          trailing: Row(
                            mainAxisSize: MainAxisSize.min,
                            children: [
                              IconButton(
                                icon: const Icon(
                                  Icons.edit,
                                  size: 20,
                                  color: Colors.white38,
                                ),
                                onPressed: () => _editHome(context, home),
                              ),
                              IconButton(
                                icon: const Icon(
                                  Icons.delete_outline,
                                  size: 20,
                                  color: Colors.redAccent,
                                ),
                                onPressed: () => _confirmDelete(context, home),
                              ),
                            ],
                          ),
                          onTap: () => _selectHome(context, home),
                        ),
                      );
                    },
                  ),
          ),
          const Padding(
            padding: EdgeInsets.only(bottom: 10),
            child: BuildInfoText(),
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        backgroundColor: Colors.deepOrange,
        onPressed: () => _addHome(context),
        child: const Icon(Icons.add),
      ),
    );
  }

  void _selectHome(BuildContext context, HomeConfig home) async {
    try {
      await ref.read(currentHomeProvider.notifier).switchTo(home);
      await ref.read(authInfoProvider.notifier).load(failOnError: true);
      if (context.mounted) {
        Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (_) => const RemoteScreen()),
        );
      }
    } catch (e) {
      if (context.mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Не удалось выбрать дом: $e')));
      }
    }
  }

  void _addHome(BuildContext context) {
    Navigator.of(
      context,
    ).push(MaterialPageRoute(builder: (_) => const HomeEditScreen()));
  }

  void _editHome(BuildContext context, HomeConfig home) {
    Navigator.of(
      context,
    ).push(MaterialPageRoute(builder: (_) => HomeEditScreen(home: home)));
  }

  void _confirmDelete(BuildContext context, HomeConfig home) {
    showDialog(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Удалить дом?'),
        content: Text('Удалить "${home.name}" (${home.url})?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(ctx).pop(),
            child: const Text('Отмена'),
          ),
          TextButton(
            onPressed: () async {
              Navigator.of(ctx).pop();
              await ref.read(homesProvider.notifier).remove(home.id);
              await syncGeofenceTask(ref.read(homesProvider));
            },
            child: const Text(
              'Удалить',
              style: TextStyle(color: Colors.redAccent),
            ),
          ),
        ],
      ),
    );
  }
}

class _EmptyHomesView extends StatelessWidget {
  const _EmptyHomesView();

  @override
  Widget build(BuildContext context) {
    return const Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(Icons.home_outlined, size: 64, color: Colors.white24),
          SizedBox(height: 16),
          Text(
            'Нет добавленных домов',
            style: TextStyle(color: Colors.white54, fontSize: 16),
          ),
          SizedBox(height: 8),
          Text(
            'Добавьте сервер Ignis',
            style: TextStyle(color: Colors.white38, fontSize: 14),
          ),
        ],
      ),
    );
  }
}

class _HomeSubtitle extends StatelessWidget {
  final HomeConfig home;
  final UserLocation location;
  final double? distKm;

  const _HomeSubtitle({
    required this.home,
    required this.location,
    required this.distKm,
  });

  @override
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(
          home.url,
          style: const TextStyle(color: Colors.white38, fontSize: 12),
        ),
        if (distKm != null)
          Padding(
            padding: const EdgeInsets.only(top: 2),
            child: Row(
              children: [
                const Icon(Icons.near_me, size: 11, color: Colors.white30),
                const SizedBox(width: 4),
                Text(
                  '~${formatDistance(distKm!)}',
                  style: const TextStyle(color: Colors.white30, fontSize: 11),
                ),
              ],
            ),
          )
        else if (home.hasCoordinates && !location.hasPosition)
          Row(
            children: [
              const Icon(Icons.location_on, size: 12, color: Colors.white24),
              const SizedBox(width: 4),
              Text(
                location.error ?? 'Координаты заданы',
                style: const TextStyle(color: Colors.white24, fontSize: 11),
              ),
            ],
          ),
      ],
    );
  }
}