import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:em2rp/models/event_model.dart';
import 'package:em2rp/models/equipment_model.dart';
import 'package:em2rp/providers/event_provider.dart';
import 'package:em2rp/providers/equipment_provider.dart';
import 'package:em2rp/providers/local_user_provider.dart';
import 'package:em2rp/services/event_preparation_service.dart';
import 'package:em2rp/utils/colors.dart';
import 'package:em2rp/views/widgets/nav/custom_app_bar.dart';
import 'package:em2rp/views/widgets/event/equipment_checklist_item.dart';
import 'package:em2rp/views/widgets/event/missing_equipment_dialog.dart';
import 'package:em2rp/views/widgets/event/preparation_success_dialog.dart';

class EventPreparationPage extends StatefulWidget {
  final String eventId;

  const EventPreparationPage({
    super.key,
    required this.eventId,
  });

  @override
  State<EventPreparationPage> createState() => _EventPreparationPageState();
}

class _EventPreparationPageState extends State<EventPreparationPage> {
  final EventPreparationService _preparationService = EventPreparationService();
  EventModel? _event;
  Map<String, EquipmentModel> _equipmentMap = {};
  Map<String, int> _returnedQuantities = {}; // Pour les quantités retournées (consommables)
  bool _isLoading = true;
  bool _isSaving = false;

  // Mode déterminé automatiquement
  bool get _isReturnMode {
    if (_event == null) return false;
    // Mode retour si préparation complétée et retour pas encore complété
    return _event!.preparationStatus == PreparationStatus.completed ||
        _event!.preparationStatus == PreparationStatus.completedWithMissing;
  }

  String get _pageTitle => _isReturnMode ? 'Retour matériel' : 'Préparation matériel';

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

  Future<void> _loadEventAndEquipment() async {
    try {
      // Charger l'événement
      final eventProvider = context.read<EventProvider>();
      final event = await eventProvider.getEvent(widget.eventId);

      if (event == null) {
        throw Exception('Événement non trouvé');
      }

      // Charger tous les équipements assignés
      final equipmentProvider = context.read<EquipmentProvider>();
      final Map<String, EquipmentModel> equipmentMap = {};

      for (var assignedEq in event.assignedEquipment) {
        final equipment = await equipmentProvider.getEquipmentById(assignedEq.equipmentId);
        if (equipment != null) {
          equipmentMap[assignedEq.equipmentId] = equipment;

          // Initialiser les quantités retournées pour les consommables
          if (_isReturnMode &&
              (equipment.category == EquipmentCategory.consumable ||
               equipment.category == EquipmentCategory.cable)) {
            _returnedQuantities[assignedEq.equipmentId] = assignedEq.returnedQuantity ?? assignedEq.quantity;
          }
        }
      }

      setState(() {
        _event = event;
        _equipmentMap = equipmentMap;
        _isLoading = false;
      });
    } catch (e) {
      setState(() => _isLoading = false);
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('Erreur: $e'),
            backgroundColor: Colors.red,
          ),
        );
      }
    }
  }

  Future<void> _toggleEquipmentValidation(String equipmentId, bool isValidated) async {
    try {
      if (_isReturnMode) {
        if (isValidated) {
          final returnedQty = _returnedQuantities[equipmentId];
          await _preparationService.validateEquipmentReturn(
            widget.eventId,
            equipmentId,
            returnedQuantity: returnedQty,
          );
        }
      } else {
        await _preparationService.validateEquipmentPreparation(widget.eventId, equipmentId);
      }

      // Recharger l'événement
      await _loadEventAndEquipment();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Erreur: $e'), backgroundColor: Colors.red),
        );
      }
    }
  }

  Future<void> _validateAllQuickly() async {
    setState(() => _isSaving = true);

    try {
      if (_isReturnMode) {
        await _preparationService.validateAllReturn(widget.eventId, _returnedQuantities);
      } else {
        await _preparationService.validateAllPreparation(widget.eventId);
      }

      // Afficher le dialog de succès avec animation
      if (mounted) {
        await showDialog(
          context: context,
          barrierDismissible: false,
          builder: (context) => PreparationSuccessDialog(isReturnMode: _isReturnMode),
        );

        // Retour à la page précédente
        Navigator.of(context).pop();
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Erreur: $e'), backgroundColor: Colors.red),
        );
      }
    } finally {
      setState(() => _isSaving = false);
    }
  }

  Future<void> _validatePreparation() async {
    if (_event == null) return;

    // Vérifier quels équipements ne sont pas validés
    final missingEquipment = <EquipmentModel>[];
    final missingIds = <String>[];

    for (var assignedEq in _event!.assignedEquipment) {
      final isValidated = _isReturnMode ? assignedEq.isReturned : assignedEq.isPrepared;

      if (!isValidated) {
        final equipment = _equipmentMap[assignedEq.equipmentId];
        if (equipment != null) {
          missingEquipment.add(equipment);
          missingIds.add(assignedEq.equipmentId);
        }
      }
    }

    // Si tout est validé, on finalise directement
    if (missingEquipment.isEmpty) {
      await _validateAllQuickly();
      return;
    }

    // Sinon, afficher le dialog des manquants
    if (mounted) {
      final result = await showDialog<String>(
        context: context,
        builder: (context) => MissingEquipmentDialog(
          missingEquipments: missingEquipment,
          eventId: widget.eventId,
          isReturnMode: _isReturnMode,
        ),
      );

      if (result == 'confirm_with_missing') {
        setState(() => _isSaving = true);
        try {
          if (_isReturnMode) {
            await _preparationService.completeReturnWithMissing(widget.eventId, missingIds);
          } else {
            await _preparationService.completePreparationWithMissing(widget.eventId, missingIds);
          }

          if (mounted) {
            await showDialog(
              context: context,
              barrierDismissible: false,
              builder: (context) => PreparationSuccessDialog(isReturnMode: _isReturnMode),
            );
            Navigator.of(context).pop();
          }
        } catch (e) {
          if (mounted) {
            ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(content: Text('Erreur: $e'), backgroundColor: Colors.red),
            );
          }
        } finally {
          setState(() => _isSaving = false);
        }
      } else if (result == 'validate_missing') {
        // Valider tous les manquants
        setState(() => _isSaving = true);
        try {
          for (var equipmentId in missingIds) {
            await _toggleEquipmentValidation(equipmentId, true);
          }
          await _validateAllQuickly();
        } finally {
          setState(() => _isSaving = false);
        }
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final userProvider = context.watch<LocalUserProvider>();
    final userId = userProvider.uid;
    final hasManagePermission = userProvider.hasPermission('manage_events');

    // Vérifier si l'utilisateur fait partie de l'équipe
    final isInWorkforce = _event?.workforce.any((ref) => ref.id == userId) ?? false;
    final hasPermission = hasManagePermission || isInWorkforce;

    if (!hasPermission) {
      return Scaffold(
        appBar: const CustomAppBar(title: 'Accès refusé'),
        body: const Center(
          child: Text('Vous n\'avez pas les permissions pour accéder à cette page.'),
        ),
      );
    }

    return Scaffold(
      appBar: CustomAppBar(title: _pageTitle),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : _event == null
              ? const Center(child: Text('Événement introuvable'))
              : Column(
                  children: [
                    // En-tête avec info de l'événement
                    _buildEventHeader(),

                    // Bouton "Tout confirmer"
                    _buildQuickValidateButton(),

                    // Liste des équipements
                    Expanded(child: _buildEquipmentList()),

                    // Bouton de validation final
                    _buildValidateButton(),
                  ],
                ),
    );
  }

  Widget _buildEventHeader() {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: AppColors.rouge.withOpacity(0.1),
        border: Border(
          bottom: BorderSide(color: Colors.grey.shade300),
        ),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            _event!.name,
            style: const TextStyle(
              fontSize: 20,
              fontWeight: FontWeight.bold,
            ),
          ),
          const SizedBox(height: 4),
          Text(
            '${_event!.assignedEquipment.length} équipement(s) assigné(s)',
            style: TextStyle(color: Colors.grey.shade700),
          ),
        ],
      ),
    );
  }

  Widget _buildQuickValidateButton() {
    return Container(
      padding: const EdgeInsets.all(16),
      child: ElevatedButton.icon(
        onPressed: _isSaving ? null : _validateAllQuickly,
        style: ElevatedButton.styleFrom(
          backgroundColor: Colors.green,
          minimumSize: const Size(double.infinity, 50),
        ),
        icon: const Icon(Icons.check_circle, color: Colors.white),
        label: Text(
          _isReturnMode ? 'Tout confirmer comme retourné' : 'Tout confirmer comme préparé',
          style: const TextStyle(color: Colors.white, fontSize: 16),
        ),
      ),
    );
  }

  Widget _buildEquipmentList() {
    return ListView.builder(
      padding: const EdgeInsets.all(16),
      itemCount: _event!.assignedEquipment.length,
      itemBuilder: (context, index) {
        final assignedEq = _event!.assignedEquipment[index];
        final equipment = _equipmentMap[assignedEq.equipmentId];

        if (equipment == null) {
          return const SizedBox.shrink();
        }

        final isValidated = _isReturnMode ? assignedEq.isReturned : assignedEq.isPrepared;

        return EquipmentChecklistItem(
          equipment: equipment,
          isValidated: isValidated,
          onValidate: (value) => _toggleEquipmentValidation(assignedEq.equipmentId, value),
          isReturnMode: _isReturnMode,
          quantity: assignedEq.quantity,
          returnedQuantity: _returnedQuantities[assignedEq.equipmentId],
          onReturnedQuantityChanged: _isReturnMode
              ? (value) {
                  setState(() {
                    _returnedQuantities[assignedEq.equipmentId] = value;
                  });
                }
              : null,
        );
      },
    );
  }

  Widget _buildValidateButton() {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: Colors.white,
        boxShadow: [
          BoxShadow(
            color: Colors.grey.withOpacity(0.3),
            spreadRadius: 1,
            blurRadius: 5,
            offset: const Offset(0, -2),
          ),
        ],
      ),
      child: ElevatedButton(
        onPressed: _isSaving ? null : _validatePreparation,
        style: ElevatedButton.styleFrom(
          backgroundColor: AppColors.rouge,
          minimumSize: const Size(double.infinity, 50),
        ),
        child: _isSaving
            ? const CircularProgressIndicator(color: Colors.white)
            : Text(
                _isReturnMode ? 'Finaliser le retour' : 'Finaliser la préparation',
                style: const TextStyle(color: Colors.white, fontSize: 16),
              ),
      ),
    );
  }
}