Modify the gritter response on restitution request

presentation/maarchRM/Presenter/medona/archiveModification.php

@@ -71,17 +71,23 @@ class archiveModification
         } else {
             $success = count($result['success']);
             $echec = count($result['error']);
+            $this->json->message='';
 
-            $this->json->message = '%1$s archive(s) flagged for restitution.';
-            $this->json->message = $this->translator->getText($this->json->message);
-            $this->json->message = sprintf($this->json->message, $success);
+            if ($success > 0) {
+                $this->json->message = '%1$s archive(s) flagged for restitution.';
+                $this->json->message = $this->translator->getText($this->json->message);
+                $this->json->message = sprintf($this->json->message, $success);
+            }
 
             if ($echec > 0) {
-                $message = '%1$s archive(s) can not be flagged.';
+                if ($success > 0) {
+                    $this->json->message .= '<br>';
+                }
+                $message = '%1$s archive(s) can not be flagged because an action is already in progress on this(these) archive(s) (or on one of its/their objects).';
                 $message = $this->translator->getText($message);
                 $message = sprintf($message, $echec);
 
-                $this->json->message .= ' '.$message;
+                $this->json->message .= $message;
             }
         }