text: //
  //  Created by Andrew Podkovyrin
  //  Copyright © 2019 Dash Core Group. All rights reserved.
  //
  //  Licensed under the MIT License (the "License");
  //  you may not use this file except in compliance with the License.
  //  You may obtain a copy of the License at
  //
  //  https://opensource.org/licenses/MIT
  //
  //  Unless required by applicable law or agreed to in writing, software
  //  distributed under the License is distributed on an "AS IS" BASIS,
  //  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  //  See the License for the specific language governing permissions and
  //  limitations under the License.
  //
  
  #import <Foundation/Foundation.h>
  
  NS_ASSUME_NONNULL_BEGIN
  
  @protocol CLMTimeFetcher;
  @class CLMAlertCampaign;
  
  @protocol CLMStateKeeper
  
  @property (readonly, nonatomic, assign) NSTimeInterval lastDisplayTimeInterval;
  @property (readonly, nonatomic, assign) NSTimeInterval lastFetchTimeInterval;
  @property (readonly, nonatomic, copy) NSArray<NSString *> *impressionIDs;
  
  - (void)recordAlertImpression:(CLMAlertCampaign *)alertCampaign;
  - (void)recordFetch;
  
  @end
  
  /// A wrapper around NSUserDefaults to store internal states.
  @interface CLMStateKeeper : NSObject <CLMStateKeeper>
  
  - (instancetype)initWithUserDefaults:(NSUserDefaults *)userDefaults
                           timeFetcher:(id<CLMTimeFetcher>)timeFetcher;
  
  - (instancetype)init NS_UNAVAILABLE;
  + (instancetype)new NS_UNAVAILABLE;
  
  @end
  
  NS_ASSUME_NONNULL_END
  