MediaChannelRelay.swift

//
//  JoinChannelVC.swift
//  APIExample
//
//  Created by 张乾泽 on 2020/4/17.
//  Copyright © 2020 Agora Corp. All rights reserved.
//
import UIKit
import AGEVideoLayout
import AgoraRtcKit

class MediaChannelRelayEntry : UIViewController
{
    @IBOutlet weak var joinButton: UIButton!
    @IBOutlet weak var channelTextField: UITextField!
    let identifier = "MediaChannelRelay"
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    @IBAction func doJoinPressed(sender: UIButton) {
        guard let channelName = channelTextField.text else {return}
        //resign channel text field
        channelTextField.resignFirstResponder()
        
        let storyBoard: UIStoryboard = UIStoryboard(name: identifier, bundle: nil)
        // create new view controller every time to ensure we get a clean vc
        guard let newViewController = storyBoard.instantiateViewController(withIdentifier: identifier) as? BaseViewController else {return}
        newViewController.title = channelName
        newViewController.configs = ["channelName":channelName]
        self.navigationController?.pushViewController(newViewController, animated: true)
    }
}

class MediaChannelRelayMain: BaseViewController {
    var localVideo = Bundle.loadView(fromNib: "VideoView", withType: VideoView.self)
    var remoteVideo = Bundle.loadView(fromNib: "VideoView", withType: VideoView.self)
    
    @IBOutlet weak var container: AGEVideoContainer!
    @IBOutlet weak var relayButton: UIButton!
    @IBOutlet weak var stopButton: UIButton!
    @IBOutlet weak var relayChannelField: UITextField!
    var agoraKit: AgoraRtcEngineKit!
    
    // indicate if current instance has joined channel
    var isJoined: Bool = false
    var isRelaying: Bool = false {
        didSet {
            stopButton.isHidden = !isRelaying
            relayButton.isHidden = isRelaying
            relayChannelField.isEnabled = !isRelaying
        }
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // layout render view
        localVideo.setPlaceholder(text: "Local Host".localized)
        remoteVideo.setPlaceholder(text: "Remote Host".localized)
        container.layoutStream(views: [localVideo, remoteVideo])
        
        // set up agora instance when view loadedlet config = AgoraRtcEngineConfig()
        let config = AgoraRtcEngineConfig()
        config.appId = KeyCenter.AppId
        config.areaCode = GlobalSettings.shared.area.rawValue
        // setup log file path
        let logConfig = AgoraLogConfig()
        logConfig.level = .info
        config.logConfig = logConfig
        
        agoraKit = AgoraRtcEngineKit.sharedEngine(with: config, delegate: self)
        
        // get channel name from configs
        guard let channelName = configs["channelName"] as? String,
              let resolution = GlobalSettings.shared.getSetting(key: "resolution")?.selectedOption().value as? CGSize,
              let fps = GlobalSettings.shared.getSetting(key: "fps")?.selectedOption().value as? AgoraVideoFrameRate,
              let orientation = GlobalSettings.shared.getSetting(key: "orientation")?.selectedOption().value as? AgoraVideoOutputOrientationMode else {return}
        
        
        // make myself a broadcaster
        agoraKit.setChannelProfile(.liveBroadcasting)
        agoraKit.setClientRole(.broadcaster)
        
        // enable video module and set up video encoding configs
        agoraKit.enableVideo()
        agoraKit.setVideoEncoderConfiguration(AgoraVideoEncoderConfiguration(size: resolution,
                frameRate: fps,
                bitrate: AgoraVideoBitrateStandard,
                orientationMode: orientation))
        
        // set up local video to render your local camera preview
        let videoCanvas = AgoraRtcVideoCanvas()
        videoCanvas.uid = 0
        // the view to be binded
        videoCanvas.view = localVideo.videoView
        videoCanvas.renderMode = .hidden
        agoraKit.setupLocalVideo(videoCanvas)
        
        // Set audio route to speaker
        agoraKit.setDefaultAudioRouteToSpeakerphone(true)
        
        // start joining channel
        // 1. Users can only see each other after they join the
        // same channel successfully using the same app id.
        // 2. If app certificate is turned on at dashboard, token is needed
        // when joining channel. The channel name and uid used to calculate
        // the token has to match the ones used for channel join
        let option = AgoraRtcChannelMediaOptions()
        let result = agoraKit.joinChannel(byToken: KeyCenter.Token, channelId: channelName, info: nil, uid: SCREEN_SHARE_BROADCASTER_UID, options: option)
        if result != 0 {
            // Usually happens with invalid parameters
            // Error code description can be found at:
            // en: https://docs.agora.io/en/Voice/API%20Reference/oc/Constants/AgoraErrorCode.html
            // cn: https://docs.agora.io/cn/Voice/API%20Reference/oc/Constants/AgoraErrorCode.html
            self.showAlert(title: "Error", message: "joinChannel call failed: \(result), please check your params")
        }
    }
    
    /// start relay
    @IBAction func doRelay(_ sender: UIButton) {
        guard let destinationChannelName = relayChannelField.text else {return}
        
        // prevent operation if target channel name is empty
        if(destinationChannelName.isEmpty) {
            self.showAlert(message: "Destination channel name is empty")
            return
        }
        
        // configure source info, channel name defaults to current, and uid defaults to local
        let config = AgoraChannelMediaRelayConfiguration()
        config.sourceInfo = AgoraChannelMediaRelayInfo(token: nil)
        
        // configure target channel info
        let destinationInfo = AgoraChannelMediaRelayInfo(token: nil)
        config.setDestinationInfo(destinationInfo, forChannelName: destinationChannelName)
        agoraKit.startChannelMediaRelay(config)
    }
    
    /// stop relay
    @IBAction func doStop(_ sender: UIButton) {
        agoraKit.stopChannelMediaRelay()
    }
    
    override func willMove(toParent parent: UIViewController?) {
        if parent == nil {
            // leave channel when exiting the view
            // deregister packet processing
            AgoraCustomEncryption.deregisterPacketProcessing(agoraKit)
            if isJoined {
                agoraKit.leaveChannel { (stats) -> Void in
                    LogUtils.log(message: "left channel, duration: \(stats.duration)", level: .info)
                }
            }
        }
    }
}

/// agora rtc engine delegate events
extension MediaChannelRelayMain: AgoraRtcEngineDelegate {
    /// callback when warning occured for agora sdk, warning can usually be ignored, still it's nice to check out
    /// what is happening
    /// Warning code description can be found at:
    /// en: https://docs.agora.io/en/Voice/API%20Reference/oc/Constants/AgoraWarningCode.html
    /// cn: https://docs.agora.io/cn/Voice/API%20Reference/oc/Constants/AgoraWarningCode.html
    /// @param warningCode warning code of the problem
    func rtcEngine(_ engine: AgoraRtcEngineKit, didOccurWarning warningCode: AgoraWarningCode) {
        LogUtils.log(message: "warning: \(warningCode.description)", level: .warning)
    }
    
    /// callback when error occured for agora sdk, you are recommended to display the error descriptions on demand
    /// to let user know something wrong is happening
    /// Error code description can be found at:
    /// en: https://docs.agora.io/en/Voice/API%20Reference/oc/Constants/AgoraErrorCode.html
    /// cn: https://docs.agora.io/cn/Voice/API%20Reference/oc/Constants/AgoraErrorCode.html
    /// @param errorCode error code of the problem
    func rtcEngine(_ engine: AgoraRtcEngineKit, didOccurError errorCode: AgoraErrorCode) {
        LogUtils.log(message: "error: \(errorCode)", level: .error)
        self.showAlert(title: "Error", message: "Error \(errorCode.description) occur")
    }
    
    /// callback when the local user joins a specified channel.
    /// @param channel
    /// @param uid uid of local user
    /// @param elapsed time elapse since current sdk instance join the channel in ms
    func rtcEngine(_ engine: AgoraRtcEngineKit, didJoinChannel channel: String, withUid uid: UInt, elapsed: Int) {
        isJoined = true
        LogUtils.log(message: "Join \(channel) with uid \(uid) elapsed \(elapsed)ms", level: .info)
    }
    
    /// callback when a remote user is joinning the channel, note audience in live broadcast mode will NOT trigger this event
    /// @param uid uid of remote joined user
    /// @param elapsed time elapse since current sdk instance join the channel in ms
    func rtcEngine(_ engine: AgoraRtcEngineKit, didJoinedOfUid uid: UInt, elapsed: Int) {
        LogUtils.log(message: "remote user join: \(uid) \(elapsed)ms", level: .info)
        
        // Only one remote video view is available for this
        // tutorial. Here we check if there exists a surface
        // view tagged as this uid.
        let videoCanvas = AgoraRtcVideoCanvas()
        videoCanvas.uid = uid
        // the view to be binded
        videoCanvas.view = remoteVideo.videoView
        videoCanvas.renderMode = .hidden
        agoraKit.setupRemoteVideo(videoCanvas)
    }
    
    /// callback when a remote user is leaving the channel, note audience in live broadcast mode will NOT trigger this event
    /// @param uid uid of remote joined user
    /// @param reason reason why this user left, note this event may be triggered when the remote user
    /// become an audience in live broadcasting profile
    func rtcEngine(_ engine: AgoraRtcEngineKit, didOfflineOfUid uid: UInt, reason: AgoraUserOfflineReason) {
        LogUtils.log(message: "remote user left: \(uid) reason \(reason)", level: .info)
        
        // to unlink your view from sdk, so that your view reference will be released
        // note the video will stay at its last frame, to completely remove it
        // you will need to remove the EAGL sublayer from your binded view
        let videoCanvas = AgoraRtcVideoCanvas()
        videoCanvas.uid = uid
        // the view to be binded
        videoCanvas.view = nil
        videoCanvas.renderMode = .hidden
        agoraKit.setupRemoteVideo(videoCanvas)
    }
    
    /// callback when a media relay process state changed
    /// @param state state of media relay
    /// @param error error details if media relay reaches failure state
    func rtcEngine(_ engine: AgoraRtcEngineKit, channelMediaRelayStateDidChange state: AgoraChannelMediaRelayState, error: AgoraChannelMediaRelayError) {
        LogUtils.log(message: "channelMediaRelayStateDidChange: \(state.rawValue) error \(error.rawValue)", level: .info)
        
        switch(state){
        case .running:
            isRelaying = true
            break
        case .failure:
            showAlert(message: "Media Relay Failed: \(error.rawValue)")
            isRelaying = false
            break
        case .idle:
            isRelaying = false
            break
        default:break
        }
    }
    
    /// callback when a media relay event received
    /// @param event  event of media relay
    func rtcEngine(_ engine: AgoraRtcEngineKit, didReceive event: AgoraChannelMediaRelayEvent) {
        LogUtils.log(message: "didReceiveRelayEvent: \(event.rawValue)", level: .info)
    }
}