reply message from thread and room

back/mails/utils/mailBuilder.ts

@@ -13,7 +13,7 @@ export default class MailBuilder {
         this.message.to = addresses;
         return this;
     }
-    
+
     cc(addresses: string[] | string): MailBuilder {
         this.message.cc = addresses;
         return this;
@@ -43,4 +43,10 @@ export default class MailBuilder {
         this.message.inReplyTo = messageID;
         return this;
     }
-}
+
+    inReplySubject(originSubject: string): MailBuilder {
+        // todo concate if multiple ?
+        this.message.subject = "RE: " + originSubject;
+        return this;
+    }
+}