feat: Listens for visitor IQs. (#2241)

modules/xmpp/ChatRoom.js

         return this.role === 'moderator';
     }
 
+    /**
+     * Redirected back.
+     * @param iq The received iq.
+     */
+    onVisitorIQ(iq) {
+        const visitors = $(iq).find('>visitors[xmlns="jitsi:visitors"]');
+        const response = $(iq).find('response-promotion');
+
+        if (visitors.length && response.length
+            && String(response.attr('allow')).toLowerCase() === 'true') {
+            logger.warn('Redirected back to main room.');
+
+            this.eventEmitter.emit(
+                XMPPEvents.REDIRECTED, undefined, visitors.attr('focusjid'), response.attr('username'));
+        }
+    }
+
     /**
      * Obtains the info about given media advertised (in legacy format) in the MUC presence of the participant
      * identified by the given endpoint JID. This is for mantining interop with endpoints that do not support

modules/xmpp/strophe.emuc.js

             'http://jitsi.org/jitmeet/audio', 'iq', 'set', null, null);
         this.connection.addHandler(this.onMuteVideo.bind(this),
             'http://jitsi.org/jitmeet/video', 'iq', 'set', null, null);
+        this.connection.addHandler(this.onVisitors.bind(this),
+            'jitsi:visitors', 'iq', 'set', null, null);
     }
 
     /**
 
         return true;
     }
+
+    /**
+     * A visitor IQ is received, pass it to the room.
+     * @param iq The received iq.
+     * @returns {boolean}
+     */
+    onVisitors(iq) {
+        const from = iq.getAttribute('from');
+        const room = this.rooms[Strophe.getBareJidFromJid(from)];
+
+        room?.onVisitorIQ(iq);
+
+        return true;
+    }
 }