import 'package:connectivity_plus/connectivity_plus.dart';
import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../app/theme.dart';
import '../../core/invite_storage.dart';
import '../../features/matches/team_providers.dart';
import '../../providers/auth_provider.dart';
import '../../shared/api_client.dart';
import '../../shared/models/invite_preview.dart';
import '../../shared/widgets/match_live_wordmark.dart';
import '../../shared/widgets/primary_cta.dart';
import '../../shared/widgets/screen_insets.dart';

class LoginScreen extends ConsumerStatefulWidget {
  const LoginScreen({super.key, this.inviteToken});

  final String? inviteToken;

  @override
  ConsumerState<LoginScreen> createState() => _LoginScreenState();
}

class _LoginScreenState extends ConsumerState<LoginScreen> {
  final _formKey = GlobalKey<FormState>();
  final _emailController = TextEditingController();
  final _passwordController = TextEditingController(text: 'password123');
  bool _obscure = true;
  InvitePreview? _invite;
  String? _inviteToken;
  bool _loadingInvite = false;

  @override
  void initState() {
    super.initState();
    _bootstrapInvite();
  }

  Future<void> _bootstrapInvite() async {
    _inviteToken = widget.inviteToken ?? await InviteStorage.readToken();
    if (_inviteToken == null) return;

    setState(() => _loadingInvite = true);
    try {
      final preview = await ApiClient().fetchInvitePreview(_inviteToken!);
      if (!mounted) return;
      setState(() {
        _invite = preview;
        if (preview.email.isNotEmpty) {
          _emailController.text = preview.email;
        }
      });
    } catch (_) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Invito non valido o scaduto')),
        );
      }
      await InviteStorage.clear();
    } finally {
      if (mounted) setState(() => _loadingInvite = false);
    }
  }

  @override
  void dispose() {
    _emailController.dispose();
    _passwordController.dispose();
    super.dispose();
  }

  Future<void> _acceptInviteIfNeeded(ApiClient client) async {
    final token = _inviteToken;
    if (token == null) return;

    try {
      final message = await client.acceptInvitation(token);
      await InviteStorage.clear();
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text(message)),
        );
      }
    } on DioException catch (e) {
      final err = e.response?.data;
      final msg = err is Map ? (err['error'] as String?) : null;
      if (mounted && msg != null) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(msg)));
      }
      rethrow;
    }
  }

  Future<void> _login() async {
    if (!_formKey.currentState!.validate()) return;

    final connectivity = await Connectivity().checkConnectivity();
    if (connectivity.contains(ConnectivityResult.none)) {
      ref.read(authProvider.notifier).setError(
            'Nessuna connessione. Disattiva la modalità aereo e verifica Wi‑Fi.',
          );
      return;
    }

    ref.read(authProvider.notifier).setLoading(true);
    try {
      final client = ApiClient();
      final result = await client.login(
        email: _emailController.text.trim(),
        password: _passwordController.text,
      );
      ref.read(authProvider.notifier).setSession(
            user: result.user,
            accessToken: result.tokens.accessToken,
            refreshToken: result.tokens.refreshToken,
          );

      final authed = ApiClient(accessToken: result.tokens.accessToken);
      if (_inviteToken != null) {
        await _acceptInviteIfNeeded(authed);
      }

      ref.invalidate(teamsProvider);
      ref.invalidate(matchesProvider);
      ref.read(authProvider.notifier).setLoading(false);
      if (mounted) context.go('/matches');
      return;
    } on DioException catch (e) {
      if (e.response?.statusCode == 422) {
        ref.read(authProvider.notifier).setLoading(false);
        return;
      }
      final message = switch (e.type) {
        DioExceptionType.connectionTimeout ||
        DioExceptionType.receiveTimeout ||
        DioExceptionType.connectionError =>
          'Server non raggiungibile. Verifica che il backend sia avviato (docker compose up).',
        DioExceptionType.badResponse when e.response?.statusCode == 401 =>
          'Email o password non corretti',
        _ => 'Errore di rete: ${e.message}',
      };
      ref.read(authProvider.notifier).setError(message);
    } catch (e) {
      ref.read(authProvider.notifier).setError('Errore imprevisto: $e');
    }
    ref.read(authProvider.notifier).setLoading(false);
  }

  @override
  Widget build(BuildContext context) {
    final auth = ref.watch(authProvider);
    final theme = Theme.of(context);

    return Scaffold(
      body: SingleChildScrollView(
        padding: ScreenInsets.contentPadding(context, horizontal: 24, vertical: 16),
        child: Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              const SizedBox(height: 32),
              const Center(child: MatchLiveWordmark(showSlogan: true)),
              const SizedBox(height: 48),
              if (_loadingInvite)
                const Padding(
                  padding: EdgeInsets.only(bottom: 16),
                  child: Center(
                    child: CircularProgressIndicator(color: AppTheme.primaryRed),
                  ),
                ),
              if (_invite != null) ...[
                Container(
                  padding: const EdgeInsets.all(14),
                  decoration: BoxDecoration(
                    color: AppTheme.surfaceElevated,
                    borderRadius: BorderRadius.circular(10),
                    border: Border.all(color: AppTheme.primaryRed.withValues(alpha: 0.35)),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        'Invito staff',
                        style: theme.textTheme.titleMedium?.copyWith(color: AppTheme.primaryRed),
                      ),
                      const SizedBox(height: 6),
                      Text(
                        'Entra in ${_invite!.teamName} come responsabile trasmissione.',
                        style: theme.textTheme.bodyMedium,
                      ),
                      const SizedBox(height: 4),
                      Text(
                        'Accedi con ${_invite!.email}',
                        style: theme.textTheme.bodySmall,
                      ),
                    ],
                  ),
                ),
                const SizedBox(height: 20),
              ],
              Text(
                'ACCEDI',
                style: theme.textTheme.headlineMedium,
                textAlign: TextAlign.center,
              ),
              const SizedBox(height: 8),
              Text(
                _invite != null
                    ? 'Usa l\'email dell\'invito, poi collega YouTube e vai in diretta'
                    : 'Gestisci le dirette della tua squadra',
                style: theme.textTheme.bodyMedium,
                textAlign: TextAlign.center,
              ),
              const SizedBox(height: 32),
              TextFormField(
                controller: _emailController,
                keyboardType: TextInputType.emailAddress,
                readOnly: _invite != null,
                decoration: const InputDecoration(
                  labelText: 'Email',
                  hintText: 'coach@squadra.it',
                ),
                validator: (v) =>
                    v == null || v.isEmpty ? 'Inserisci l\'email' : null,
              ),
              const SizedBox(height: 16),
              TextFormField(
                controller: _passwordController,
                obscureText: _obscure,
                decoration: InputDecoration(
                  labelText: 'Password',
                  suffixIcon: IconButton(
                    icon: Icon(
                      _obscure ? Icons.visibility : Icons.visibility_off,
                    ),
                    onPressed: () => setState(() => _obscure = !_obscure),
                  ),
                ),
                validator: (v) =>
                    v == null || v.isEmpty ? 'Inserisci la password' : null,
              ),
              if (auth.error != null) ...[
                const SizedBox(height: 12),
                Text(
                  auth.error!,
                  style: theme.textTheme.bodyMedium?.copyWith(
                    color: AppTheme.primaryRed,
                  ),
                  textAlign: TextAlign.center,
                ),
              ],
              const SizedBox(height: 32),
              PrimaryCta(
                label: _invite != null ? 'ACCEDI E ACCETTA INVITO' : 'ACCEDI',
                loading: auth.loading,
                onPressed: _login,
              ),
            ],
          ),
        ),
      ),
    );
  }
}