import 'package:flutter/material.dart';

import '../models.dart';
import '../services/api_service.dart';
import '../services/auth_service.dart';
import '../services/update_service.dart';
import '../widgets/server_card.dart';
import 'settings_screen.dart';

class ServersScreen extends StatefulWidget {
  const ServersScreen({
    super.key,
    required this.auth,
    required this.api,
    required this.onLoggedOut,
  });
  final AuthService auth;
  final ApiService api;
  final VoidCallback onLoggedOut;

  @override
  State<ServersScreen> createState() => _ServersScreenState();
}

class _ServersScreenState extends State<ServersScreen> {
  List<GameServer>? _servers;
  String? _error;
  final _busy = <String>{};

  @override
  void initState() {
    super.initState();
    _refresh();
    _checkUpdate();
  }

  Future<void> _refresh() async {
    try {
      final servers = await widget.api.servers();
      if (mounted) setState(() {
        _servers = servers;
        _error = null;
      });
    } on UnauthorizedException {
      await widget.auth.logout();
      widget.onLoggedOut();
    } catch (e) {
      if (mounted) setState(() => _error = '$e');
    }
  }

  Future<void> _toggle(GameServer s) async {
    setState(() => _busy.add(s.id));
    try {
      s.isUp ? await widget.api.stop(s.id) : await widget.api.start(s.id);
      await Future.delayed(const Duration(seconds: 2));
      await _refresh();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('$e')));
      }
    } finally {
      if (mounted) setState(() => _busy.remove(s.id));
    }
  }

  Future<void> _checkUpdate() async {
    final info = await UpdateService(widget.api.baseUrl).check();
    if (info == null || !mounted) return;
    final go = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: Text('Mise à jour ${info.version}'),
        content: Text(info.notes.isEmpty ? 'Une nouvelle version est disponible.' : info.notes),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx, false), child: const Text('Plus tard')),
          FilledButton(onPressed: () => Navigator.pop(ctx, true), child: const Text('Installer')),
        ],
      ),
    );
    if (go == true) {
      final ok = await UpdateService(widget.api.baseUrl).apply(info);
      if (mounted && !ok) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Impossible d\'ouvrir le téléchargement.')),
        );
      }
    }
  }

  Future<void> _openSettings() async {
    await Navigator.push(context,
        MaterialPageRoute(builder: (_) => SettingsScreen(api: widget.api)));
    _refresh();
  }

  Future<void> _logout() async {
    await widget.auth.logout();
    widget.onLoggedOut();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Serveurs'),
        actions: [
          IconButton(onPressed: _openSettings, icon: const Icon(Icons.settings_outlined)),
          IconButton(onPressed: _logout, icon: const Icon(Icons.logout)),
        ],
      ),
      body: RefreshIndicator(
        onRefresh: _refresh,
        child: _buildBody(),
      ),
    );
  }

  Widget _buildBody() {
    if (_error != null && _servers == null) {
      return ListView(children: [
        const SizedBox(height: 120),
        Icon(Icons.cloud_off, size: 60, color: Theme.of(context).colorScheme.outline),
        const SizedBox(height: 12),
        Center(child: Text('Connexion à l\'API impossible.\n$_error', textAlign: TextAlign.center)),
        const SizedBox(height: 12),
        Center(child: FilledButton(onPressed: _refresh, child: const Text('Réessayer'))),
      ]);
    }
    if (_servers == null) {
      return const Center(child: CircularProgressIndicator());
    }

    final prod = _servers!.where((s) => !s.isPreprod).toList();
    final preprod = _servers!.where((s) => s.isPreprod).toList();

    final children = <Widget>[];
    if (prod.isNotEmpty) {
      children.add(const _SectionHeader(label: 'Production', icon: Icons.public));
      children.addAll(prod.map(_card));
    }
    if (preprod.isNotEmpty) {
      children.add(const _SectionHeader(label: 'Preprod', icon: Icons.science_outlined));
      children.addAll(preprod.map(_card));
    }

    return ListView(
      padding: const EdgeInsets.fromLTRB(16, 4, 16, 24),
      children: children,
    );
  }

  Widget _card(GameServer s) => Padding(
        padding: const EdgeInsets.only(bottom: 14),
        child: FutureBuilder<String>(
          future: widget.api.iconUrl(s.id),
          builder: (_, snap) => ServerCard(
            server: s,
            iconUrl: snap.data ?? '',
            busy: _busy.contains(s.id),
            onToggle: () => _toggle(s),
          ),
        ),
      );
}

class _SectionHeader extends StatelessWidget {
  const _SectionHeader({required this.label, required this.icon});
  final String label;
  final IconData icon;

  @override
  Widget build(BuildContext context) {
    final c = Theme.of(context).colorScheme.onSurfaceVariant;
    return Padding(
      padding: const EdgeInsets.fromLTRB(4, 14, 4, 10),
      child: Row(
        children: [
          Icon(icon, size: 18, color: c),
          const SizedBox(width: 8),
          Text(label.toUpperCase(),
              style: TextStyle(
                  color: c, fontSize: 13, fontWeight: FontWeight.w800, letterSpacing: 1.1)),
        ],
      ),
    );
  }
}