text: //
  //  FMDatabase+EncryptionKey.h
  //  CloudantSync
  //
  //  Created by Enrique de la Torre Fernandez on 27/04/2015.
  //  Copyright (c) 2015 IBM Cloudant. All rights reserved.
  //
  //  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
  //  except in compliance with the License. You may obtain a copy of the License at
  //  http://www.apache.org/licenses/LICENSE-2.0
  //  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 "FMDatabase.h"
  
  #import "CDTEncryptionKeyProvider.h"
  
  extern NSString *const FMDatabaseEncryptionKeyErrorDomain;
  
  /**
   Errors for 'setKeyWithProvider:error:'
   */
  typedef NS_ENUM(NSInteger, FMDatabaseEncryptionKeyError) {
      FMDatabaseEncryptionKeyErrorKeyNotSet,
      FMDatabaseEncryptionKeyErrorDBCorruptedOrNoKeyProvided,
      FMDatabaseEncryptionKeyErrorWrongKeyOrDBNotEncrypted
  };
  
  @interface FMDatabase (EncryptionKey)
  
  /**
   This method performs 3 steps:
   - Get an encryption key from the provider
   - Set the key (if there is any, a provider can return nil)
   - Check that the db can be read
  
   @param provider Returns the key to decipher the db (or nil)
   @param error Output param, it will contain an error if the method does not succeed
  
   @return `YES` if success, `NO` on error.
   */
  - (BOOL)setKeyWithProvider:(id<CDTEncryptionKeyProvider>)provider error:(NSError **)error;
  
  @end
  