ViewController.swift

//
//  ViewController.swift
//  sendbird_channel_change
//
//  Created by Jason.Allshorn on 08/06/2021.
//

import UIKit
import SendBirdSDK

class ViewController: UIViewController {

    override func viewDidLoad() {
        
        super.viewDidLoad()
        //Init
        let APP_ID = "APP_ID"
        SBDMain.initWithApplicationId(APP_ID)
        let USER_ID = "UserA"
        //Connect
        SBDMain.connect(withUserId: USER_ID, completionHandler: { (user, error) in
            guard error == nil else { return }
        })
    }
    
    @IBAction func getChangedChannels(_ sender: Any) {
        // Button Clicked
        self.processChangedChannels()
    }
    
    func writeLog (_ updatedChannels: [SBDGroupChannel]?, _ deletedChannels: [String]?, _ nextToken: String?) {
        print("updated channels \(updatedChannels!)")
        print("deletedChannels \(deletedChannels!)")
        //Update change log token
        
    }

    func processChangedChannels () {
        
        //Set change log params
        let params = SBDGroupChannelChangeLogsParams()
        params.includeEmptyChannel = true
        //If change log token doesn't exist locally
        if (UserDefaults.standard.string(forKey: "nextToken") == nil) {
            
            let ts = SBDMain.getLastConnectedAt()
            
            SBDMain.getMyGroupChannelChangeLogs(byTimestamp: ts, params: params) { updatedChannels, deletedChannels, hasMore, nextToken, error in
                guard error == nil else {
                    return
                }
                self.writeLog(updatedChannels, deletedChannels, nextToken)
                
            }
        } else {

            let token = UserDefaults.standard.string(forKey: "nextToken")
            SBDMain.getMyGroupChannelChangeLogs(byToken: token, params: params) { updatedChannels, deletedChannels, hasMore, nextToken, error in
                
                guard error == nil else { return }
                self.writeLog(updatedChannels, deletedChannels, nextToken)

            }
        }
    }
}