import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:em2rp/models/option_model.dart';
import 'package:em2rp/utils/colors.dart';
import 'package:intl/intl.dart';

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

  @override
  State<OptionsManagement> createState() => _OptionsManagementState();
}

class _OptionsManagementState extends State<OptionsManagement> {
  String _searchQuery = '';
  List<EventOption> _options = [];
  Map<String, String> _eventTypeNames = {};
  bool _loading = true;

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

  Future<void> _loadData() async {
    setState(() => _loading = true);
    try {
      // Charger les types d'événements pour les noms
      final eventTypesSnapshot = await FirebaseFirestore.instance
          .collection('eventTypes')
          .get();

      _eventTypeNames = {
        for (var doc in eventTypesSnapshot.docs)
          doc.id: doc.data()['name'] as String
      };

      // Charger les options
      final optionsSnapshot = await FirebaseFirestore.instance
          .collection('options')
          .orderBy('code')
          .get();

      setState(() {
        _options = optionsSnapshot.docs
            .map((doc) => EventOption.fromMap(doc.data(), doc.id))
            .toList();
        _loading = false;
      });
    } catch (e) {
      setState(() => _loading = false);
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('Erreur lors du chargement : $e')),
      );
    }
  }

  List<EventOption> get _filteredOptions {
    if (_searchQuery.isEmpty) return _options;
    return _options.where((option) =>
        option.name.toLowerCase().contains(_searchQuery.toLowerCase()) ||
        option.code.toLowerCase().contains(_searchQuery.toLowerCase()) ||
        option.details.toLowerCase().contains(_searchQuery.toLowerCase())
    ).toList();
  }

  Future<List<Map<String, dynamic>>> _getBlockingEvents(String optionId) async {
    final eventsSnapshot = await FirebaseFirestore.instance
        .collection('events')
        .get();

    final now = DateTime.now();
    List<Map<String, dynamic>> futureEvents = [];
    List<Map<String, dynamic>> pastEvents = [];

    for (final doc in eventsSnapshot.docs) {
      final eventData = doc.data();
      final options = eventData['options'] as List<dynamic>? ?? [];

      // Vérifier si cette option est utilisée dans cet événement
      bool optionUsed = options.any((opt) => opt['id'] == optionId);

      if (optionUsed) {
        final eventDate = eventData['StartDateTime']?.toDate() ?? DateTime.now();
        // Corriger la récupération du nom - utiliser 'Name' au lieu de 'name'
        final eventName = eventData['Name'] as String? ?? 'Événement sans nom';

        if (eventDate.isAfter(now)) {
          futureEvents.add({
            'id': doc.id,
            'name': eventName,
            'startDateTime': eventDate,
          });
        } else {
          pastEvents.add({
            'id': doc.id,
            'name': eventName,
            'startDateTime': eventDate,
          });
        }
      }
    }

    return [...futureEvents, ...pastEvents];
  }

  Future<void> _deleteOption(EventOption option) async {
    final events = await _getBlockingEvents(option.id);
    final futureEvents = events.where((e) =>
        (e['startDateTime'] as DateTime).isAfter(DateTime.now())).toList();

    if (futureEvents.isNotEmpty) {
      // Il y a des événements futurs, empêcher la suppression
      _showBlockingEventsDialog(option, events, canDelete: false);
      return;
    }

    if (events.isNotEmpty) {
      // Il n'y a que des événements passés, afficher un avertissement
      _showBlockingEventsDialog(option, events, canDelete: true);
      return;
    }

    // Aucun événement, suppression directe
    _confirmAndDelete(option);
  }

  void _showBlockingEventsDialog(EventOption option, List<Map<String, dynamic>> events, {required bool canDelete}) {
    final futureEvents = events.where((e) =>
        (e['startDateTime'] as DateTime).isAfter(DateTime.now())).toList();
    final pastEvents = events.where((e) =>
        (e['startDateTime'] as DateTime).isBefore(DateTime.now())).toList();

    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(canDelete ? 'Avertissement' : 'Suppression impossible'),
        content: SizedBox(
          width: double.maxFinite,
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              if (!canDelete) ...[
                const Text(
                  'Impossible de supprimer cette option car elle est utilisée par des événements futurs :',
                  style: TextStyle(color: Colors.red, fontWeight: FontWeight.bold),
                ),
                const SizedBox(height: 12),
                ...futureEvents.map((event) => Padding(
                  padding: const EdgeInsets.only(bottom: 4),
                  child: Text(
                    '• ${event['name']} - ${DateFormat('dd/MM/yyyy').format(event['startDateTime'])}',
                    style: const TextStyle(color: Colors.red),
                  ),
                )),
              ],
              if (canDelete && pastEvents.isNotEmpty) ...[
                const Text(
                  'Cette option est utilisée par des événements passés :',
                  style: TextStyle(color: Colors.orange, fontWeight: FontWeight.bold),
                ),
                const SizedBox(height: 12),
                ...pastEvents.take(5).map((event) => Padding(
                  padding: const EdgeInsets.only(bottom: 4),
                  child: Text(
                    '• ${event['name']} - ${DateFormat('dd/MM/yyyy').format(event['startDateTime'])}',
                    style: const TextStyle(color: Colors.orange),
                  ),
                )),
                if (pastEvents.length > 5)
                  Text('... et ${pastEvents.length - 5} autres événements'),
                const SizedBox(height: 12),
                const Text('Voulez-vous vraiment continuer la suppression ?'),
              ],
            ],
          ),
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('Annuler'),
          ),
          if (canDelete)
            ElevatedButton(
              onPressed: () {
                Navigator.pop(context);
                _confirmAndDelete(option);
              },
              style: ElevatedButton.styleFrom(backgroundColor: Colors.red),
              child: const Text('Supprimer quand même', style: TextStyle(color: Colors.white)),
            ),
        ],
      ),
    );
  }

  void _confirmAndDelete(EventOption option) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Confirmer la suppression'),
        content: Text('Êtes-vous sûr de vouloir supprimer l\'option "${option.code} - ${option.name}" ?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('Annuler'),
          ),
          ElevatedButton(
            onPressed: () async {
              Navigator.pop(context);
              try {
                await FirebaseFirestore.instance
                    .collection('options')
                    .doc(option.id)
                    .delete();

                ScaffoldMessenger.of(context).showSnackBar(
                  const SnackBar(content: Text('Option supprimée avec succès')),
                );
                _loadData();
              } catch (e) {
                ScaffoldMessenger.of(context).showSnackBar(
                  SnackBar(content: Text('Erreur lors de la suppression : $e')),
                );
              }
            },
            style: ElevatedButton.styleFrom(backgroundColor: Colors.red),
            child: const Text('Supprimer', style: TextStyle(color: Colors.white)),
          ),
        ],
      ),
    );
  }

  void _showCreateEditDialog({EventOption? option}) {
    showDialog(
      context: context,
      builder: (context) => _OptionFormDialog(
        option: option,
        eventTypeNames: _eventTypeNames,
        onSaved: _loadData,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(16.0),
      child: Column(
        children: [
          // Header avec recherche et bouton ajouter
          Row(
            children: [
              Expanded(
                child: TextField(
                  decoration: const InputDecoration(
                    labelText: 'Rechercher une option (code, nom, détails)',
                    prefixIcon: Icon(Icons.search),
                    border: OutlineInputBorder(),
                  ),
                  onChanged: (value) => setState(() => _searchQuery = value),
                ),
              ),
              const SizedBox(width: 16),
              ElevatedButton.icon(
                onPressed: () => _showCreateEditDialog(),
                icon: const Icon(Icons.add),
                label: const Text('Nouvelle option'),
                style: ElevatedButton.styleFrom(
                  backgroundColor: AppColors.rouge,
                  foregroundColor: Colors.white,
                ),
              ),
            ],
          ),
          const SizedBox(height: 16),

          // Liste des options
          Expanded(
            child: _loading
                ? const Center(child: CircularProgressIndicator())
                : _filteredOptions.isEmpty
                    ? const Center(
                        child: Text(
                          'Aucune option trouvée',
                          style: TextStyle(fontSize: 16, color: Colors.grey),
                        ),
                      )
                    : ListView.builder(
                        itemCount: _filteredOptions.length,
                        itemBuilder: (context, index) {
                          final option = _filteredOptions[index];
                          final currencyFormat = NumberFormat.currency(locale: 'fr_FR', symbol: '€');

                          return Card(
                            margin: const EdgeInsets.only(bottom: 8),
                            child: ListTile(
                              leading: CircleAvatar(
                                backgroundColor: AppColors.rouge,
                                child: Text(
                                  option.code.substring(0, 2).toUpperCase(),
                                  style: const TextStyle(
                                    color: Colors.white,
                                    fontWeight: FontWeight.bold,
                                    fontSize: 12,
                                  ),
                                ),
                              ),
                              title: Text(
                                '${option.code} - ${option.name}',
                                style: const TextStyle(fontWeight: FontWeight.bold),
                              ),
                              subtitle: Column(
                                crossAxisAlignment: CrossAxisAlignment.start,
                                children: [
                                  if (option.details.isNotEmpty)
                                    Text(option.details),
                                  const SizedBox(height: 4),
                                  Text(
                                    'Prix : ${currencyFormat.format(option.valMin)} - ${currencyFormat.format(option.valMax)}',
                                    style: const TextStyle(
                                      fontWeight: FontWeight.w500,
                                      color: Colors.green,
                                    ),
                                  ),
                                  const SizedBox(height: 4),
                                  Wrap(
                                    spacing: 4,
                                    children: option.eventTypes.map((typeId) {
                                      final typeName = _eventTypeNames[typeId] ?? typeId;
                                      return Chip(
                                        label: Text(
                                          typeName,
                                          style: const TextStyle(fontSize: 10),
                                        ),
                                        materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
                                        backgroundColor: AppColors.rouge.withOpacity(0.1),
                                      );
                                    }).toList(),
                                  ),
                                ],
                              ),
                              trailing: Row(
                                mainAxisSize: MainAxisSize.min,
                                children: [
                                  IconButton(
                                    icon: const Icon(Icons.edit, color: Colors.blue),
                                    onPressed: () => _showCreateEditDialog(option: option),
                                    tooltip: 'Modifier',
                                  ),
                                  IconButton(
                                    icon: const Icon(Icons.delete, color: Colors.red),
                                    onPressed: () => _deleteOption(option),
                                    tooltip: 'Supprimer',
                                  ),
                                ],
                              ),
                            ),
                          );
                        },
                      ),
          ),
        ],
      ),
    );
  }
}

class _OptionFormDialog extends StatefulWidget {
  final EventOption? option;
  final Map<String, String> eventTypeNames;
  final VoidCallback onSaved;

  const _OptionFormDialog({
    this.option,
    required this.eventTypeNames,
    required this.onSaved,
  });

  @override
  State<_OptionFormDialog> createState() => _OptionFormDialogState();
}

class _OptionFormDialogState extends State<_OptionFormDialog> {
  final _formKey = GlobalKey<FormState>();
  final _codeController = TextEditingController();
  final _nameController = TextEditingController();
  final _detailsController = TextEditingController();
  final _minPriceController = TextEditingController();
  final _maxPriceController = TextEditingController();
  List<String> _selectedTypes = [];
  bool _loading = false;
  String? _error;

  @override
  void initState() {
    super.initState();
    if (widget.option != null) {
      _codeController.text = widget.option!.code;
      _nameController.text = widget.option!.name;
      _detailsController.text = widget.option!.details;
      _minPriceController.text = widget.option!.valMin.toString();
      _maxPriceController.text = widget.option!.valMax.toString();
      _selectedTypes = List.from(widget.option!.eventTypes);
    }
  }

  @override
  void dispose() {
    _codeController.dispose();
    _nameController.dispose();
    _detailsController.dispose();
    _minPriceController.dispose();
    _maxPriceController.dispose();
    super.dispose();
  }

  Future<bool> _isCodeUnique(String code) async {
    final doc = await FirebaseFirestore.instance
        .collection('options')
        .doc(code)
        .get();

    // Si on modifie et que c'est le même document, c'est OK
    if (widget.option != null && widget.option!.id == code) {
      return true;
    }

    return !doc.exists;
  }

  Future<void> _submit() async {
    if (!_formKey.currentState!.validate()) return;
    if (_selectedTypes.isEmpty) {
      setState(() => _error = 'Sélectionnez au moins un type d\'événement');
      return;
    }

    final code = _codeController.text.trim().toUpperCase();
    final name = _nameController.text.trim();
    final min = double.tryParse(_minPriceController.text.replaceAll(',', '.'));
    final max = double.tryParse(_maxPriceController.text.replaceAll(',', '.'));

    if (min == null || max == null) {
      setState(() => _error = 'Les prix doivent être des nombres valides');
      return;
    }

    if (min > max) {
      setState(() => _error = 'Le prix minimum ne peut pas être supérieur au prix maximum');
      return;
    }

    setState(() => _loading = true);

    try {
      // Vérifier l'unicité du code seulement pour les nouvelles options
      if (widget.option == null) {
        final isUnique = await _isCodeUnique(code);
        if (!isUnique) {
          setState(() {
            _error = 'Ce code d\'option existe déjà';
            _loading = false;
          });
          return;
        }
      }

      final data = {
        'code': code,
        'name': name,
        'details': _detailsController.text.trim(),
        'valMin': min,
        'valMax': max,
        'eventTypes': _selectedTypes,
      };

      if (widget.option == null) {
        // Création - utiliser le code comme ID
        await FirebaseFirestore.instance.collection('options').doc(code).set(data);
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Option créée avec succès')),
        );
      } else {
        // Modification
        await FirebaseFirestore.instance
            .collection('options')
            .doc(widget.option!.id)
            .update(data);
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Option modifiée avec succès')),
        );
      }

      widget.onSaved();
      Navigator.pop(context);
    } catch (e) {
      setState(() {
        _error = 'Erreur : $e';
        _loading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Text(widget.option == null ? 'Nouvelle option' : 'Modifier l\'option'),
      content: SizedBox(
        width: 500,
        child: SingleChildScrollView(
          child: Form(
            key: _formKey,
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                TextFormField(
                  controller: _codeController,
                  decoration: const InputDecoration(
                    labelText: 'Code de l\'option *',
                    hintText: 'Ex: TENT_50M2',
                    helperText: 'Max 16 caractères, lettres, chiffres, _ et -',
                    border: OutlineInputBorder(),
                  ),
                  enabled: widget.option == null, // Code non modifiable en édition
                  maxLength: 16,
                  textCapitalization: TextCapitalization.characters,
                  validator: (v) {
                    if (v == null || v.isEmpty) return 'Le code est obligatoire';
                    if (v.length > 16) return 'Maximum 16 caractères';
                    if (!RegExp(r'^[A-Z0-9_-]+$').hasMatch(v)) {
                      return 'Seuls les lettres, chiffres, _ et - sont autorisés';
                    }
                    return null;
                  },
                ),
                const SizedBox(height: 16),
                TextFormField(
                  controller: _nameController,
                  decoration: const InputDecoration(
                    labelText: 'Nom de l\'option *',
                    border: OutlineInputBorder(),
                  ),
                  validator: (v) => v == null || v.trim().isEmpty ? 'Le nom est obligatoire' : null,
                ),
                const SizedBox(height: 16),
                TextFormField(
                  controller: _detailsController,
                  decoration: const InputDecoration(
                    labelText: 'Détails',
                    border: OutlineInputBorder(),
                  ),
                  maxLines: 3,
                ),
                const SizedBox(height: 16),
                Row(
                  children: [
                    Expanded(
                      child: TextFormField(
                        controller: _minPriceController,
                        decoration: const InputDecoration(
                          labelText: 'Prix min (€) *',
                          border: OutlineInputBorder(),
                        ),
                        keyboardType: const TextInputType.numberWithOptions(decimal: true),
                        validator: (v) => v == null || v.isEmpty ? 'Obligatoire' : null,
                      ),
                    ),
                    const SizedBox(width: 8),
                    Expanded(
                      child: TextFormField(
                        controller: _maxPriceController,
                        decoration: const InputDecoration(
                          labelText: 'Prix max (€) *',
                          border: OutlineInputBorder(),
                        ),
                        keyboardType: const TextInputType.numberWithOptions(decimal: true),
                        validator: (v) => v == null || v.isEmpty ? 'Obligatoire' : null,
                      ),
                    ),
                  ],
                ),
                const SizedBox(height: 16),
                Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    const Text('Types d\'événement associés *',
                        style: TextStyle(fontWeight: FontWeight.w500)),
                    const SizedBox(height: 8),
                    Wrap(
                      spacing: 8,
                      children: widget.eventTypeNames.entries.map((entry) {
                        return FilterChip(
                          label: Text(entry.value),
                          selected: _selectedTypes.contains(entry.key),
                          onSelected: (selected) {
                            setState(() {
                              if (selected) {
                                _selectedTypes.add(entry.key);
                              } else {
                                _selectedTypes.remove(entry.key);
                              }
                              _error = null; // Effacer l'erreur lors de la sélection
                            });
                          },
                          selectedColor: AppColors.rouge.withOpacity(0.3),
                        );
                      }).toList(),
                    ),
                  ],
                ),
                if (_error != null) ...[
                  const SizedBox(height: 16),
                  Text(
                    _error!,
                    style: const TextStyle(color: Colors.red),
                  ),
                ],
              ],
            ),
          ),
        ),
      ),
      actions: [
        TextButton(
          onPressed: _loading ? null : () => Navigator.pop(context),
          child: const Text('Annuler'),
        ),
        ElevatedButton(
          onPressed: _loading ? null : _submit,
          style: ElevatedButton.styleFrom(
            backgroundColor: AppColors.rouge,
            foregroundColor: Colors.white,
          ),
          child: _loading
              ? const SizedBox(
                  width: 20,
                  height: 20,
                  child: CircularProgressIndicator(strokeWidth: 2),
                )
              : Text(widget.option == null ? 'Créer' : 'Modifier'),
        ),
      ],
    );
  }
}