import 'package:flutter/material.dart';
import '../utils/constants.dart';
import '../models/allarme.dart';
import '../services/api_service.dart';
import '../widgets/allarme_card.dart';

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

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

class _HomeScreenState extends State<HomeScreen> {
  final _apiService = ApiService();
  List<Allarme> _allarmi = [];
  List<Allarme> _allarmiFiltered = [];
  bool _isLoading = true;
  String? _errorMessage;
  String? _selectedSeverita;
  String _searchQuery = '';
  String _sortBy = 'data_desc'; // data_desc, data_asc, severita

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

  Future<void> _loadAllarmi({bool refresh = false}) async {
    if (refresh) setState(() => _isLoading = true);

    try {
      final response = await _apiService.getAllarmi(severita: _selectedSeverita);
      setState(() {
        _allarmi = response.items;
        _applyFiltersAndSort();
        _isLoading = false;
      });
    } catch (e) {
      setState(() {
        _errorMessage = 'Errore caricamento allarmi';
        _isLoading = false;
      });
    }
  }

  void _applyFiltersAndSort() {
    // Filtra per ricerca
    var filtered = _allarmi.where((allarme) {
      if (_searchQuery.isEmpty) return true;
      final query = _searchQuery.toLowerCase();
      return allarme.titolo.toLowerCase().contains(query) ||
          allarme.descrizione?.toLowerCase().contains(query) == true ||
          allarme.tipoReadable.toLowerCase().contains(query);
    }).toList();

    // Ordina
    switch (_sortBy) {
      case 'data_desc':
        filtered.sort((a, b) => b.timestampRilevamento.compareTo(a.timestampRilevamento));
        break;
      case 'data_asc':
        filtered.sort((a, b) => a.timestampRilevamento.compareTo(b.timestampRilevamento));
        break;
      case 'severita':
        filtered.sort((a, b) {
          final severityOrder = {'critical': 0, 'warning': 1, 'info': 2};
          return (severityOrder[a.severita] ?? 3).compareTo(severityOrder[b.severita] ?? 3);
        });
        break;
    }

    _allarmiFiltered = filtered;
  }

  void _showFilterDialog() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Filtri'),
        content: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            ListTile(
              title: const Text('Tutti'),
              leading: Radio<String?>(value: null, groupValue: _selectedSeverita, onChanged: (val) { Navigator.pop(context); setState(() => _selectedSeverita = val); _loadAllarmi(refresh: true); }),
            ),
            ListTile(
              title: const Text('CRITICO'),
              leading: Radio<String?>(value: 'critical', groupValue: _selectedSeverita, onChanged: (val) { Navigator.pop(context); setState(() => _selectedSeverita = val); _loadAllarmi(refresh: true); }),
            ),
            ListTile(
              title: const Text('AVVISO'),
              leading: Radio<String?>(value: 'warning', groupValue: _selectedSeverita, onChanged: (val) { Navigator.pop(context); setState(() => _selectedSeverita = val); _loadAllarmi(refresh: true); }),
            ),
          ],
        ),
      ),
    );
  }

  void _showSortDialog() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Ordina per'),
        content: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            _buildSortOption('data_desc', 'Più recenti', Icons.arrow_downward),
            _buildSortOption('data_asc', 'Meno recenti', Icons.arrow_upward),
            _buildSortOption('severita', 'Severità', Icons.warning),
          ],
        ),
      ),
    );
  }

  Widget _buildSortOption(String value, String label, IconData icon) {
    final isSelected = _sortBy == value;

    return ListTile(
      leading: Icon(
        icon,
        color: isSelected ? AppColors.primary : AppColors.textSecondary,
      ),
      title: Text(
        label,
        style: TextStyle(
          fontWeight: isSelected ? FontWeight.bold : FontWeight.normal,
          color: isSelected ? AppColors.primary : null,
        ),
      ),
      trailing: isSelected ? const Icon(Icons.check, color: AppColors.primary) : null,
      onTap: () {
        Navigator.pop(context);
        setState(() {
          _sortBy = value;
          _applyFiltersAndSort();
        });
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Column(
          children: [Text('ASE Monitor'), Text('Allarmi Attivi', style: TextStyle(fontSize: 12))],
        ),
        actions: [
          IconButton(icon: const Icon(Icons.sort), onPressed: _showSortDialog),
          IconButton(icon: const Icon(Icons.filter_list), onPressed: _showFilterDialog),
        ],
      ),
      body: Column(
        children: [
          // Search bar
          Padding(
            padding: const EdgeInsets.all(AppSizes.paddingM),
            child: TextField(
              decoration: InputDecoration(
                hintText: 'Cerca allarmi...',
                prefixIcon: const Icon(Icons.search),
                suffixIcon: _searchQuery.isNotEmpty
                    ? IconButton(
                        icon: const Icon(Icons.clear),
                        onPressed: () {
                          setState(() {
                            _searchQuery = '';
                            _applyFiltersAndSort();
                          });
                        },
                      )
                    : null,
                border: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(12),
                ),
                filled: true,
                fillColor: Colors.grey[100],
              ),
              onChanged: (value) {
                setState(() {
                  _searchQuery = value;
                  _applyFiltersAndSort();
                });
              },
            ),
          ),
          // Results count
          if (_searchQuery.isNotEmpty)
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: AppSizes.paddingM),
              child: Text(
                '${_allarmiFiltered.length} risultati trovati',
                style: AppTextStyles.bodySmall.copyWith(color: AppColors.textSecondary),
              ),
            ),
          // List
          Expanded(
            child: _isLoading
                ? const Center(child: CircularProgressIndicator())
                : _errorMessage != null
                    ? Center(child: Column(mainAxisAlignment: MainAxisAlignment.center, children: [const Icon(Icons.error_outline, size: 64, color: AppColors.critical), Text(_errorMessage!)]))
                    : _allarmiFiltered.isEmpty
                  ? const Center(child: Column(mainAxisAlignment: MainAxisAlignment.center, children: [Icon(Icons.check_circle_outline, size: 64, color: AppColors.success), SizedBox(height: 16), Text('Nessun allarme', style: AppTextStyles.h3)]))
                  : RefreshIndicator(
                      onRefresh: () => _loadAllarmi(refresh: true),
                      child: ListView.builder(
                        padding: const EdgeInsets.all(AppSizes.paddingM),
                        itemCount: _allarmiFiltered.length,
                        itemBuilder: (context, index) => AllarmeCard(allarme: _allarmiFiltered[index]),
                      ),
                    ),
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () => _loadAllarmi(refresh: true),
        child: const Icon(Icons.refresh),
      ),
    );
  }
}