content: import '../data_classes/filter/FilterPreferences.dart';
  import '../data_classes/settings/MensaColorScheme.dart';
  import '../data_classes/settings/MealPlanFormat.dart';
  import '../data_classes/settings/PriceCategory.dart';
  
  /// This is an interface to the local storage.
  abstract class ILocalStorage {
    /// Returns the client identifier.
    String? getClientIdentifier();
  
    /// Sets the device identifier.
    Future<void> setClientIdentifier(String identifier);
  
    /// Returns the FilterPreferences.
    FilterPreferences? getFilterPreferences();
  
    /// Sets the FilterPreferences.
    Future<void> setFilterPreferences(FilterPreferences filter);
  
    /// Returns the saved canteen id.
    String? getCanteen();
  
    /// Sets the committed id of the canteen.
    Future<void> setCanteen(String canteen);
  
    /// Returns the saved ColorScheme.
    MensaColorScheme? getColorScheme();
  
    /// Sets the committed ColorScheme.
    Future<void> setColorScheme(MensaColorScheme scheme);
  
    /// Returns the saved PriceCategory.
    PriceCategory? getPriceCategory();
  
    /// Sets the committed PriceCategory.
    Future<void> setPriceCategory(PriceCategory category);
  
    /// Returns the saved MealPlanFormat.
    MealPlanFormat? getMealPlanFormat();
  
    /// Sets the committed MealPlanFormat.
    Future<void> setMealPlanFormat(MealPlanFormat format);
  }