/// [ChangeNotifier] that loads, filters, and mutates the in-memory item list.
library;

import 'package:flutter/foundation.dart';

import '../models/item.dart';
import '../services/item_repository.dart';
import '../services/storage_service.dart';

/// App-wide catalog state. Screens call [loadItems], [addItem], and [search].
class ItemController extends ChangeNotifier {
  ItemController({
    required this._repository,
    required this._storage,
  }) {
    _repository.useRemoteData = _storage.useRemoteData;
  }

  final ItemRepository _repository;
  final StorageService _storage;

  List<Item> _items = const [];
  bool _isLoading = false;
  String? _error;

  List<Item> get items => List.unmodifiable(_items);
  bool get isLoading => _isLoading;
  String? get error => _error;
  bool get useRemoteData => _repository.useRemoteData;
  int get count => _items.length;

  Future<void> loadItems() async {
    _isLoading = true;
    _error = null;
    notifyListeners();

    try {
      // Small delay so the loading indicator is visible with local data.
      await Future<void>.delayed(const Duration(milliseconds: 250));
      _items = await _repository.fetchItems();
    } catch (error, stackTrace) {
      _error = 'Could not load items.';
      debugPrint('ItemController.loadItems failed: $error\n$stackTrace');
    } finally {
      _isLoading = false;
      notifyListeners();
    }
  }

  Future<void> setUseRemoteData(bool value) async {
    if (value == _repository.useRemoteData) return;
    _repository.useRemoteData = value;
    await _storage.setUseRemoteData(value);
    notifyListeners();
    await loadItems();
  }

  /// Case-insensitive match against title, subtitle, and category.
  List<Item> search(String query) {
    final needle = query.trim().toLowerCase();
    if (needle.isEmpty) return items;

    return _items.where((item) {
      return item.title.toLowerCase().contains(needle) ||
          item.subtitle.toLowerCase().contains(needle) ||
          item.category.label.toLowerCase().contains(needle);
    }).toList(growable: false);
  }

  Item addItem({
    required String title,
    required String subtitle,
    required String description,
    required ItemCategory category,
  }) {
    final created = _repository.createLocal(
      title: title,
      subtitle: subtitle,
      description: description,
      category: category,
    );
    _items = [created, ..._items];
    notifyListeners();
    return created;
  }

  Item? findById(String id) {
    for (final item in _items) {
      if (item.id == id) return item;
    }
    return null;
  }
}