import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import '../../core/auth/auth_notifier.dart';
import '../../core/api/api_client_provider.dart';
import '../../core/chat/unread_notifier.dart';
import '../../core/pairing/pairing_notifier.dart';
import '../chat/widgets/pricing_bottom_sheet.dart';

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

  @override
  ConsumerState<HomeScreen> createState() => _HomeScreenState();
}

class _HomeScreenState extends ConsumerState<HomeScreen> with WidgetsBindingObserver {
  Map<String, dynamic>? _activeSession;
  bool _loadingSession = true;

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

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

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      _checkActiveSession();
    }
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _checkActiveSession();
  }

  Future<void> _checkActiveSession() async {
    try {
      final apiClient = ref.read(apiClientProvider);
      final response = await apiClient.get('/api/client/chat/session/active');
      final data = response['data'];
      if (mounted) {
        setState(() {
          _activeSession = data is Map<String, dynamic> ? data : null;
          _loadingSession = false;
        });
      }
    } catch (_) {
      if (mounted) setState(() => _loadingSession = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final authState = ref.watch(authProvider);
    final authData = authState.valueOrNull;

    final displayName = switch (authData) {
      AuthAuthenticatedData d => d.profile['display_name'] as String? ?? '',
      AuthAnonymousData d => d.displayName,
      _ => '',
    };

    ref.listen(pairingProvider, (prev, next) {
      if (next is PairingSearchingData) {
        context.go('/chat/searching');
      } else if (next is PairingNoBestieData) {
        context.go('/chat/no-bestie');
      } else if (next is PairingErrorData) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text(next.message)),
        );
      }
    });

    return Scaffold(
        appBar: AppBar(
          title: const Text('Halo Bestie'),
          actions: [
            IconButton(
              icon: const Icon(Icons.history),
              onPressed: () => context.push('/chat/history'),
            ),
            IconButton(
              icon: const Icon(Icons.logout),
              onPressed: () => ref.read(authProvider.notifier).logout(),
            ),
          ],
        ),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.all(32),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Text('Halo, $displayName!', style: const TextStyle(fontSize: 24)),
                const SizedBox(height: 32),
                if (_loadingSession)
                  const CircularProgressIndicator()
                else if (_activeSession != null)
                  _ActiveSessionCard(
                    session: _activeSession!,
                    onTap: () {
                      final sessionId = _activeSession!['id'] as String;
                      final mitraName = _activeSession!['mitra_display_name'] as String? ?? 'Bestie';
                      context.push('/chat/session/$sessionId', extra: mitraName);
                    },
                  )
                else ...[
                  const SizedBox(height: 16),
                  ElevatedButton(
                    style: ElevatedButton.styleFrom(
                      padding: const EdgeInsets.symmetric(horizontal: 48, vertical: 16),
                    ),
                    onPressed: () => PricingBottomSheet.show(context),
                    child: const Text('Mulai Curhat', style: TextStyle(fontSize: 18)),
                  ),
                ],
              ],
            ),
          ),
        ),
    );
  }
}

class _ActiveSessionCard extends ConsumerWidget {
  final Map<String, dynamic> session;
  final VoidCallback onTap;

  const _ActiveSessionCard({required this.session, required this.onTap});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final mitraName = session['mitra_display_name'] as String? ?? 'Bestie';
    final unreadCount = ref.watch(unreadCountProvider);

    return Card(
      elevation: 2,
      child: InkWell(
        onTap: onTap,
        borderRadius: BorderRadius.circular(12),
        child: Padding(
          padding: const EdgeInsets.all(20),
          child: Row(
            children: [
              Badge(
                isLabelVisible: unreadCount > 0,
                label: Text('$unreadCount'),
                child: const CircleAvatar(
                  backgroundColor: Colors.green,
                  child: Icon(Icons.chat, color: Colors.white),
                ),
              ),
              const SizedBox(width: 16),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    const Text(
                      'Sesi Aktif',
                      style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
                    ),
                    const SizedBox(height: 4),
                    Text(
                      'Sedang curhat dengan $mitraName',
                      style: const TextStyle(fontSize: 14, color: Colors.grey),
                    ),
                  ],
                ),
              ),
              const Icon(Icons.chevron_right),
            ],
          ),
        ),
      ),
    );
  }
}