rooms-android/app/src/main/java/com/nextcloud/talk/adapters/ParticipantDisplayItem.java

package com.nextcloud.talk.adapters;

import android.os.Handler;
import android.os.Looper;
import android.text.TextUtils;

import com.nextcloud.talk.call.CallParticipantModel;
import com.nextcloud.talk.utils.ApiUtils;

import org.webrtc.EglBase;
import org.webrtc.MediaStream;
import org.webrtc.PeerConnection;

public class ParticipantDisplayItem {

    public interface Observer {
        void onChange();
    }

    /**
     * Shared handler to receive change notifications from the model on the main thread.
     */
    private static final Handler handler = new Handler(Looper.getMainLooper());

    private final ParticipantDisplayItemNotifier participantDisplayItemNotifier = new ParticipantDisplayItemNotifier();

    private final String baseUrl;
    private final String defaultGuestNick;
    private final EglBase rootEglBase;

    private final String session;
    private final String streamType;

    private final CallParticipantModel callParticipantModel;

    private final CallParticipantModel.Observer callParticipantModelObserver = this::updateFromModel;

    private String userId;
    private PeerConnection.IceConnectionState iceConnectionState;
    private String nick;
    private String urlForAvatar;
    private MediaStream mediaStream;
    private boolean streamEnabled;
    private boolean isAudioEnabled;

    public ParticipantDisplayItem(String baseUrl, String defaultGuestNick, EglBase rootEglBase, String streamType,
                                  CallParticipantModel callParticipantModel) {
        this.baseUrl = baseUrl;
        this.defaultGuestNick = defaultGuestNick;
        this.rootEglBase = rootEglBase;

        this.session = callParticipantModel.getSessionId();
        this.streamType = streamType;

        this.callParticipantModel = callParticipantModel;
        this.callParticipantModel.addObserver(callParticipantModelObserver, handler);

        updateFromModel();
    }

    public void destroy() {
        this.callParticipantModel.removeObserver(callParticipantModelObserver);
    }

    private void updateFromModel() {
        userId = callParticipantModel.getUserId();
        nick = callParticipantModel.getNick();

        this.updateUrlForAvatar();

        if ("screen".equals(streamType)) {
            iceConnectionState = callParticipantModel.getScreenIceConnectionState();
            mediaStream = callParticipantModel.getScreenMediaStream();
            isAudioEnabled = true;
            streamEnabled = true;
        } else {
            iceConnectionState = callParticipantModel.getIceConnectionState();
            mediaStream = callParticipantModel.getMediaStream();
            isAudioEnabled = callParticipantModel.isAudioAvailable() != null ?
                callParticipantModel.isAudioAvailable() : false;
            streamEnabled = callParticipantModel.isVideoAvailable() != null ?
                callParticipantModel.isVideoAvailable() : false;
        }

        participantDisplayItemNotifier.notifyChange();
    }

    private void updateUrlForAvatar() {
        if (!TextUtils.isEmpty(userId)) {
            urlForAvatar = ApiUtils.getUrlForAvatar(baseUrl, userId, true);
        } else {
            urlForAvatar = ApiUtils.getUrlForGuestAvatar(baseUrl, getNick(), true);
        }
    }

    public boolean isConnected() {
        return iceConnectionState == PeerConnection.IceConnectionState.CONNECTED ||
            iceConnectionState == PeerConnection.IceConnectionState.COMPLETED ||
            // If there is no connection state that means that no connection is needed, so it is a special case that is
            // also seen as "connected".
            iceConnectionState == null;
    }

    public String getNick() {
        if (TextUtils.isEmpty(userId) && TextUtils.isEmpty(nick)) {
            return defaultGuestNick;
        }

        return nick;
    }

    public String getUrlForAvatar() {
        return urlForAvatar;
    }

    public MediaStream getMediaStream() {
        return mediaStream;
    }

    public boolean isStreamEnabled() {
        return streamEnabled;
    }

    public EglBase getRootEglBase() {
        return rootEglBase;
    }

    public boolean isAudioEnabled() {
        return isAudioEnabled;
    }

    public void addObserver(Observer observer) {
        participantDisplayItemNotifier.addObserver(observer);
    }

    public void removeObserver(Observer observer) {
        participantDisplayItemNotifier.removeObserver(observer);
    }

    @Override
    public String toString() {
        return "ParticipantSession{" +
                "userId='" + userId + '\'' +
                ", session='" + session + '\'' +
                ", nick='" + nick + '\'' +
                ", urlForAvatar='" + urlForAvatar + '\'' +
                ", mediaStream=" + mediaStream +
                ", streamType='" + streamType + '\'' +
                ", streamEnabled=" + streamEnabled +
                ", rootEglBase=" + rootEglBase +
                '}';
    }
}