import 'dart:async';

import 'package:external_repos/external_repos.dart';
import 'package:injectable/injectable.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'package:uae_stat/domain/repos/t_favorites_repo.dart';

@dev
@prod
@Injectable(as: TFavoritesRepo)
class PFavoritesRepo implements TFavoritesRepo {
  static const _key = 'favorite_indicators';

  Future<Set<IndicatorEnum>> _load() async {
    final prefs = await SharedPreferences.getInstance();
    final raw = prefs.getStringList(_key) ?? [];
    return raw
        .map(
          (s) => IndicatorEnum.values.firstWhere((id) => id.name == s),
        )
        .toSet();
  }

  Future<void> _save(Set<IndicatorEnum> ids) async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.setStringList(_key, ids.map((e) => e.name).toList());
  }

  @override
  FutureOr<Set<IndicatorEnum>> getAll() => _load();

  @override
  Future<void> removeExisting(IndicatorEnum id) async {
    final favs = await _load();
    favs.remove(id);
    await _save(favs);
  }

  @override
  Future<void> addNew(IndicatorEnum id) async {
    final favs = await _load();
    favs.add(id);
    await _save(favs);
  }
}