Add SipUaHelperListener onNewInfo callback

lib/src/sip_ua_helper.dart

@@ -351,6 +351,10 @@ class SIPUAHelper extends EventManager {
       });
     });
 
+    handlers.on(EventNewInfo(), (EventNewInfo event) {
+      _notifyInfoListeners(event);
+    });
+
     handlers.on(EventReInvite(), (EventReInvite event) {
       logger.d('Reinvite received in helper, notifying listeners');
       _notifyReInviteListeners(event);
@@ -520,6 +524,22 @@ class SIPUAHelper extends EventManager {
       listener.onNewNotify(Notify(request: event.request));
     }
   }
+
+  void _notifyInfoListeners(EventNewInfo event) {
+    // Copy to prevent concurrent modification exception
+    List<SipUaHelperListener> listeners = _sipUaHelperListeners.toList();
+    final IncomingRequest? request =
+        event.request is IncomingRequest ? event.request as IncomingRequest : null;
+    final SipInfo info = SipInfo(
+      contentType: event.info?.contentType ?? request?.getHeader('content-type'),
+      body: event.info?.body ?? request?.body,
+      request: request,
+      originator: event.originator,
+    );
+    for (SipUaHelperListener listener in listeners) {
+      listener.onNewInfo(info);
+    }
+  }
 }
 
 enum CallStateEnum {
@@ -775,13 +795,22 @@ abstract class SipUaHelperListener {
   void onNewMessage(SIPMessageRequest msg);
   void onNewNotify(Notify ntf);
   void onNewReinvite(ReInvite event);
+  void onNewInfo(SipInfo info) {}
 }
 
 class Notify {
   Notify({this.request});
   IncomingRequest? request;
 }
 
+class SipInfo {
+  SipInfo({this.contentType, this.body, this.request, this.originator});
+  String? contentType;
+  String? body;
+  IncomingRequest? request;
+  Originator? originator;
+}
+
 class ReInvite {
   ReInvite({this.hasVideo, this.hasAudio, this.sdp, this.accept, this.reject});
   bool? hasVideo;