make transcriber leave a conference based on participants presence (j…

…itsi#129)

* make transcriber leave a conference based on participants presence

* remove TranscriptionStatus from Jigasi

* change leave logic of Transcriber to use TranscriptionRequestExtension

* update jitsi-desk

pom.xml

@@ -20,7 +20,7 @@
   <properties>
     <assembly.skipAssembly>true</assembly.skipAssembly>
     <smack.version>4.2.1</smack.version>
-    <jitsi-desktop.version>2.13.812e3ed</jitsi-desktop.version>
+    <jitsi-desktop.version>2.13.5160aa9</jitsi-desktop.version>
   </properties>
 
   <dependencies>

src/main/java/org/jitsi/jigasi/TranscriptionGatewaySession.java

@@ -23,7 +23,6 @@
 import net.java.sip.communicator.service.protocol.event.*;
 import net.java.sip.communicator.service.protocol.media.*;
 import org.jitsi.jigasi.transcription.*;
-import org.jitsi.jigasi.xmpp.*;
 import org.jitsi.service.neomedia.*;
 import org.jitsi.service.neomedia.device.*;
 import org.jitsi.util.*;
@@ -58,6 +57,12 @@ public class TranscriptionGatewaySession
      */
     public final static String DISPLAY_NAME = "Transcriber";
 
+    /**
+     * How long the transcriber should wait until really leaving the conference
+     * when no participant is requesting transcription anymore.
+     */
+    public final static int PRESENCE_UPDATE_WAIT_UNTIL_LEAVE_DURATION = 2500;
+
     /**
      * The TranscriptionService used by this session
      */
@@ -296,6 +301,27 @@ void notifyChatRoomMemberUpdated(ChatRoomMember chatMember, Presence presence)
         {
             this.transcriber.updateParticipantTargetLanguage(identifier, null);
         }
+
+        if(transcriber.isTranscribing() &&
+            !transcriber.isAnyParticipantRequestingTranscription())
+        {
+            new Thread(() ->
+            {
+                try
+                {
+                    Thread.sleep(PRESENCE_UPDATE_WAIT_UNTIL_LEAVE_DURATION);
+                }
+                catch (InterruptedException e)
+                {
+                    e.printStackTrace();
+                }
+
+                if(!transcriber.isAnyParticipantRequestingTranscription())
+                {
+                    jvbConference.stop();
+                }
+            }).start();
+        }
     }
 
     @Override

src/main/java/org/jitsi/jigasi/transcription/Participant.java

@@ -342,6 +342,13 @@ private AvatarIdPacketExtension getAvatarIdExtensionOrNull(Presence p)
             AvatarIdPacketExtension.NAME_SPACE);
     }
 
+    private TranscriptionRequestExtension
+                getTranscriptionRequestExtensionOrNull(Presence p)
+    {
+        return p.getExtension(TranscriptionRequestExtension.ELEMENT_NAME,
+                              TranscriptionRequestExtension.NAMESPACE);
+    }
+
     /**
      * Get the ssrc of the audio of this participant
      *
@@ -364,7 +371,9 @@ public long getSSRC()
      */
     public String getSourceLanguage()
     {
-        return sourceLanguageLocale.getLanguage();
+        return sourceLanguageLocale == null ?
+            null :
+            sourceLanguageLocale.getLanguage();
     }
 
     /**
@@ -384,7 +393,14 @@ public String getTranslationLanguage()
      */
     public void setSourceLanguage(String language)
     {
-        sourceLanguageLocale = Locale.forLanguageTag(language);
+        if (language == null)
+        {
+            sourceLanguageLocale = null;
+        }
+        else
+        {
+            sourceLanguageLocale = Locale.forLanguageTag(language);
+        }
     }
 
     /**
@@ -617,4 +633,37 @@ private static long getConferenceMemberAudioSSRC(
         // bitwise AND to fix signed int casted to long
         return confMember.getAudioSsrc() & 0xffffffffL;
     }
+
+    /**
+     * Check whether this Participant is requesting a source language
+     *
+     * @return true when the source language is set and non-empty, false
+     * otherwise.
+     */
+    public boolean hasValidSourceLanguage()
+    {
+        String lang = this.getSourceLanguage();
+
+        return lang != null && !lang.isEmpty();
+    }
+
+    /**
+     * Get whether this {@link Participant} is requesting transcription by
+     * checking the {@link TranscriptionRequestExtension} in the
+     * {@link Presence}
+     *
+     * @return true when the {@link Participant} is requesting transcription,
+     * false otherwise
+     */
+    public boolean isRequestingTranscription()
+    {
+        ChatRoomMemberJabberImpl memberJabber
+            = ((ChatRoomMemberJabberImpl) this.chatMember);
+
+        TranscriptionRequestExtension ext
+            = getTranscriptionRequestExtensionOrNull(
+                memberJabber.getLastPresence());
+
+        return ext != null && Boolean.valueOf(ext.getText());
+    }
 }

src/main/java/org/jitsi/jigasi/transcription/Transcriber.java

@@ -611,10 +611,14 @@ public void bufferReceived(ReceiveStream receiveStream, Buffer buffer)
         long ssrc = receiveStream.getSSRC() & 0xffffffffL;
 
         Participant p = findParticipant(ssrc);
+
         if (p != null)
         {
-            logger.trace("Gave audio to buffer");
-            p.giveBuffer(buffer);
+            if (p.hasValidSourceLanguage())
+            {
+                logger.trace("Gave audio to buffer");
+                p.giveBuffer(buffer);
+            }
         }
         else
         {
@@ -660,6 +664,25 @@ private Participant getParticipant(String identifier)
         }
     }
 
+    /**
+     * Check whether any {@link Participant} are requesting transcription
+     *
+     * @return true when at least one {@link Participant} is requesting
+     * transcription, false otherwise
+     */
+    public boolean isAnyParticipantRequestingTranscription()
+    {
+        List<Participant> participantsCopy;
+        synchronized (this.participants)
+        {
+            participantsCopy = new ArrayList<>(this.participants.values());
+        }
+
+        return participantsCopy
+            .stream()
+            .anyMatch(Participant::isRequestingTranscription);
+    }
+
     /**
      * Get the MediaDevice this transcriber is listening to for audio
      *