Add getOrCreate method to directChatRepo

data/src/main/java/org/mercury_im/messenger/data/repository/XmppDirectChatRepository.java

@@ -78,6 +78,19 @@ public class XmppDirectChatRepository
                 .observeOn(observerScheduler());
     }
 
+    @Override
+    public Single<DirectChat> getOrCreateChatWithPeer(Peer _peer) {
+        return getDirectChatByPeer(_peer)
+                .switchIfEmpty(insertDirectChat(new IDirectChat(){
+                    {
+                        setAccount(_peer.getAccount());
+                        setPeer(_peer);
+                    }
+                }))
+                .subscribeOn(subscriberScheduler())
+                .observeOn(observerScheduler());
+    }
+
     @Override
     public Observable<Optional<DirectChat>> observeDirectChatByPeer(Peer peer) {
         return data().select(DirectChatModel.class)