import 'package:flutter_bloc/flutter_bloc.dart';
import '../../models/activity.dart';
import '../../repositories/activity_repository.dart';
import '../../services/activity_places_service.dart';
import '../../services/error_service.dart';
import 'activity_event.dart';
import 'activity_state.dart';

/// BLoC for managing activity-related state and operations
class ActivityBloc extends Bloc<ActivityEvent, ActivityState> {
  final ActivityRepository _repository;
  final ActivityPlacesService _placesService;
  final ErrorService _errorService;

  ActivityBloc({
    required ActivityRepository repository,
    required ActivityPlacesService placesService,
    required ErrorService errorService,
  })  : _repository = repository,
        _placesService = placesService,
        _errorService = errorService,
        super(const ActivityInitial()) {
    
    on<LoadActivities>(_onLoadActivities);
    on<SearchActivities>(_onSearchActivities);
    on<SearchActivitiesByText>(_onSearchActivitiesByText);
    on<AddActivity>(_onAddActivity);
    on<AddActivitiesBatch>(_onAddActivitiesBatch);
    on<VoteForActivity>(_onVoteForActivity);
    on<DeleteActivity>(_onDeleteActivity);
    on<FilterActivities>(_onFilterActivities);
    on<RefreshActivities>(_onRefreshActivities);
    on<ClearSearchResults>(_onClearSearchResults);
    on<UpdateActivity>(_onUpdateActivity);
    on<ToggleActivityFavorite>(_onToggleActivityFavorite);
  }

  /// Handles loading activities for a trip
  Future<void> _onLoadActivities(
    LoadActivities event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      emit(const ActivityLoading());
      
      final activities = await _repository.getActivitiesByTrip(event.tripId);
      
      emit(ActivityLoaded(
        activities: activities,
        filteredActivities: activities,
      ));
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur chargement activités: $e');
      emit(const ActivityError('Impossible de charger les activités'));
    }
  }

  /// Handles searching activities using Google Places API
  Future<void> _onSearchActivities(
    SearchActivities event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      // Si c'est un append (charger plus), on garde l'état actuel et on met isLoading à true
      if (event.appendToExisting && state is ActivitySearchResults) {
        final currentState = state as ActivitySearchResults;
        emit(currentState.copyWith(isLoading: true));
      } else {
        emit(const ActivitySearching());
      }
      
      final searchResults = await _placesService.searchActivities(
        destination: event.destination,
        tripId: event.tripId,
        category: event.category,
        maxResults: event.maxResults ?? 20, // Par défaut 20, ou utiliser la valeur spécifiée
        offset: event.offset ?? 0, // Par défaut 0
      );
      
      List<Activity> finalResults;
      
      // Si on doit ajouter aux résultats existants
      if (event.appendToExisting && state is ActivitySearchResults) {
        final currentState = state as ActivitySearchResults;
        finalResults = [...currentState.searchResults, ...searchResults];
      } else {
        finalResults = searchResults;
      }
      
      emit(ActivitySearchResults(
        searchResults: finalResults,
        query: event.category?.displayName ?? 'Toutes les activités',
        isLoading: false,
      ));
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur recherche activités: $e');
      emit(const ActivityError('Impossible de rechercher les activités'));
    }
  }

  /// Handles text-based activity search
  Future<void> _onSearchActivitiesByText(
    SearchActivitiesByText event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      emit(const ActivitySearching());
      
      final searchResults = await _placesService.searchActivitiesByText(
        query: event.query,
        destination: event.destination,
        tripId: event.tripId,
      );
      
      emit(ActivitySearchResults(
        searchResults: searchResults,
        query: event.query,
      ));
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur recherche textuelle: $e');
      emit(const ActivityError('Impossible de rechercher les activités'));
    }
  }

  /// Handles adding a single activity
  Future<void> _onAddActivity(
    AddActivity event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      // Check if activity already exists
      if (event.activity.placeId != null) {
        final existing = await _repository.findExistingActivity(
          event.activity.tripId,
          event.activity.placeId!,
        );
        
        if (existing != null) {
          emit(const ActivityError('Cette activité a déjà été ajoutée'));
          return;
        }
      }

      final activityId = await _repository.addActivity(event.activity);
      
      if (activityId != null) {
        emit(ActivityAdded(
          activity: event.activity.copyWith(id: activityId),
          message: 'Activité ajoutée avec succès',
        ));
        // Reload activities
        add(LoadActivities(event.activity.tripId));
      } else {
        emit(const ActivityError('Impossible d\'ajouter l\'activité'));
      }
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur ajout activité: $e');
      emit(const ActivityError('Impossible d\'ajouter l\'activité'));
    }
  }

  /// Handles adding multiple activities in batch
  Future<void> _onAddActivitiesBatch(
    AddActivitiesBatch event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      // Filter out existing activities
      final filteredActivities = <Activity>[];
      
      emit(ActivityBatchAdding(
        activitiesToAdd: event.activities,
        progress: 0,
        total: event.activities.length,
      ));
      
      for (int i = 0; i < event.activities.length; i++) {
        final activity = event.activities[i];
        
        if (activity.placeId != null) {
          final existing = await _repository.findExistingActivity(
            activity.tripId,
            activity.placeId!,
          );
          
          if (existing == null) {
            filteredActivities.add(activity);
          }
        } else {
          filteredActivities.add(activity);
        }
        
        // Update progress
        emit(ActivityBatchAdding(
          activitiesToAdd: event.activities,
          progress: i + 1,
          total: event.activities.length,
        ));
      }

      if (filteredActivities.isEmpty) {
        emit(const ActivityError('Toutes les activités ont déjà été ajoutées'));
        return;
      }

      final addedIds = await _repository.addActivitiesBatch(filteredActivities);
      
      if (addedIds.isNotEmpty) {
        emit(ActivityOperationSuccess(
          '${addedIds.length} activité(s) ajoutée(s) avec succès',
          operationType: 'batch_add',
        ));
        // Reload activities
        add(LoadActivities(event.activities.first.tripId));
      } else {
        emit(const ActivityError('Impossible d\'ajouter les activités'));
      }
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur ajout en lot: $e');
      emit(const ActivityError('Impossible d\'ajouter les activités'));
    }
  }

  /// Handles voting for an activity
  Future<void> _onVoteForActivity(
    VoteForActivity event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      // Show voting state
      if (state is ActivityLoaded) {
        final currentState = state as ActivityLoaded;
        emit(ActivityVoting(
          activityId: event.activityId,
          activities: currentState.activities,
        ));
      }

      final success = await _repository.voteForActivity(
        event.activityId,
        event.userId,
        event.vote,
      );
      
      if (success) {
        emit(ActivityVoteRecorded(
          activityId: event.activityId,
          vote: event.vote,
          userId: event.userId,
        ));
        
        // Reload activities to reflect the new vote
        if (state is ActivityLoaded) {
          final currentState = state as ActivityLoaded;
          final activities = await _repository.getActivitiesByTrip(
            currentState.activities.first.tripId,
          );
          
          emit(currentState.copyWith(
            activities: activities,
            filteredActivities: _applyFilters(
              activities,
              currentState.activeFilter,
              currentState.minRating,
              currentState.showVotedOnly,
              event.userId,
            ),
          ));
        }
      } else {
        emit(const ActivityError('Impossible d\'enregistrer le vote'));
      }
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur vote: $e');
      emit(const ActivityError('Impossible d\'enregistrer le vote'));
    }
  }

  /// Handles deleting an activity
  Future<void> _onDeleteActivity(
    DeleteActivity event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      final success = await _repository.deleteActivity(event.activityId);
      
      if (success) {
        emit(ActivityDeleted(
          activityId: event.activityId,
          message: 'Activité supprimée avec succès',
        ));
        
        // Reload if we're on the activity list
        if (state is ActivityLoaded) {
          final currentState = state as ActivityLoaded;
          if (currentState.activities.isNotEmpty) {
            add(LoadActivities(currentState.activities.first.tripId));
          }
        }
      } else {
        emit(const ActivityError('Impossible de supprimer l\'activité'));
      }
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur suppression: $e');
      emit(const ActivityError('Impossible de supprimer l\'activité'));
    }
  }

  /// Handles filtering activities
  Future<void> _onFilterActivities(
    FilterActivities event,
    Emitter<ActivityState> emit,
  ) async {
    if (state is ActivityLoaded) {
      final currentState = state as ActivityLoaded;
      
      final filteredActivities = _applyFilters(
        currentState.activities,
        event.category,
        event.minRating,
        event.showVotedOnly ?? false,
        '', // UserId would be needed for showVotedOnly filter
      );
      
      emit(currentState.copyWith(
        filteredActivities: filteredActivities,
        activeFilter: event.category,
        minRating: event.minRating,
        showVotedOnly: event.showVotedOnly ?? false,
      ));
    }
  }

  /// Handles refreshing activities
  Future<void> _onRefreshActivities(
    RefreshActivities event,
    Emitter<ActivityState> emit,
  ) async {
    add(LoadActivities(event.tripId));
  }

  /// Handles clearing search results
  Future<void> _onClearSearchResults(
    ClearSearchResults event,
    Emitter<ActivityState> emit,
  ) async {
    if (state is ActivitySearchResults) {
      emit(const ActivityInitial());
    }
  }

  /// Handles updating an activity
  Future<void> _onUpdateActivity(
    UpdateActivity event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      if (state is ActivityLoaded) {
        final currentState = state as ActivityLoaded;
        emit(ActivityUpdating(
          activityId: event.activity.id,
          activities: currentState.activities,
        ));
      }

      final success = await _repository.updateActivity(event.activity);
      
      if (success) {
        emit(const ActivityOperationSuccess(
          'Activité mise à jour avec succès',
          operationType: 'update',
        ));
        
        // Reload activities
        add(LoadActivities(event.activity.tripId));
      } else {
        emit(const ActivityError('Impossible de mettre à jour l\'activité'));
      }
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur mise à jour: $e');
      emit(const ActivityError('Impossible de mettre à jour l\'activité'));
    }
  }

  /// Handles toggling activity favorite status
  Future<void> _onToggleActivityFavorite(
    ToggleActivityFavorite event,
    Emitter<ActivityState> emit,
  ) async {
    try {
      // This would require extending the Activity model to include favorites
      // For now, we'll use the voting system as a favorite system
      add(VoteForActivity(
        activityId: event.activityId,
        userId: event.userId,
        vote: 1,
      ));
    } catch (e) {
      _errorService.logError('activity_bloc', 'Erreur favori: $e');
      emit(const ActivityError('Impossible de modifier les favoris'));
    }
  }

  /// Applies filters to the activities list
  List<Activity> _applyFilters(
    List<Activity> activities,
    String? category,
    double? minRating,
    bool showVotedOnly,
    String userId,
  ) {
    var filtered = activities;

    if (category != null) {
      filtered = filtered.where((a) => a.category == category).toList();
    }

    if (minRating != null) {
      filtered = filtered.where((a) => (a.rating ?? 0) >= minRating).toList();
    }

    if (showVotedOnly && userId.isNotEmpty) {
      filtered = filtered.where((a) => a.hasUserVoted(userId)).toList();
    }

    return filtered;
  }
}