text: //
  //  SBDConstants.h
  //  SendBirdSDK
  //
  //  Created by sendbird-young on 12/10/2018.
  //  Copyright © 2018 SENDBIRD.COM. All rights reserved.
  //
  
  #ifndef SBDConstants_h
  #define SBDConstants_h
  
  #import <Foundation/Foundation.h>
  
  @class SBDGroupChannel, SBDOpenChannel;
  @class SBDBaseMessage, SBDFileMessage;
  @class SBDError;
  
  typedef void (^SBDOpenChannelHandler)(SBDOpenChannel * _Nullable channel, SBDError * _Nullable error);
  typedef void (^SBDFileMessageHandler)(SBDFileMessage * _Nullable message, SBDError * _Nullable error);
  typedef void (^SBDBinaryProgressHandler)(int64_t bytesSent, int64_t totalBytesSent, int64_t totalBytesExpectedToSend);
  typedef void (^SBDMessageChangeLogsHandler)(NSArray<SBDBaseMessage *> * _Nullable updatedMessages,
                                              NSArray<NSNumber *> * _Nullable deletedMessageIds,
                                              BOOL hasMore,
                                              NSString * _Nullable token,
                                              SBDError * _Nullable error);
  typedef void(^SBDChannelChangeLogsHandler)(NSArray <SBDGroupChannel *> * _Nullable updatedChannels,
                                             NSArray <NSString *> * _Nullable deletedChannelUrls,
                                             BOOL hasMore,
                                             NSString * _Nullable token,
                                             SBDError * _Nullable error);
  
  #endif /* SBDConstants_h */
  