The algorithm has been reworked once more, to correct a bug I introduced

during the last commit, and to make it simpler.

ui/nG6/pi6/class.tx_nG6_pi6.php

@@ -119,30 +119,42 @@ class tx_nG6_pi6 extends \TYPO3\CMS\Frontend\Plugin\AbstractPlugin {
                         	}
                            $users_id[$u["right_level_label"]][] = $u["user_id"];
                            $users_emails[$u["right_level_label"]][] = $u["email"];
-                        }      
+                        }
 
                         #Warn if mail is sent to several manager
                         $email_warn="" ;
                         $purge_email_to="";
-                        $purge_user_id_to=Array();
                         
                         if ( count( $users_emails['manager']) > 1 ) {
                         	$email_warn.="Be aware that every user associated with this project received this email, please send only one answer per purge alert number.\n";
                         }
                         
-                        $users_emails_to = array_merge($users_emails['administrator'],$users_emails['manager'],$users_emails['member']);
-                        $purge_user_id_to = array_merge($users_id['administrator'],$users_id['manager'],$users_id['member']);
+                        $purge_user_id_to = array();
+                        $users_emails_to = array();
+                        if(isset($users_emails['administrator'])){
+                        	$users_emails_to = array_merge($users_emails_to, $users_emails['administrator']);
+                        	$purge_user_id_to = array_merge($purge_user_id_to, $users_id['administrator']);
+                        }
+                        if(isset($users_emails['manager'])){
+                        	$users_emails_to = array_merge($users_emails_to,$users_emails['manager']);
+                        	$purge_user_id_to = array_merge($purge_user_id_to, $users_id['manager']);
+                        }
+                        if(isset($users_emails['member'])){
+                        	$users_emails_to = array_merge($users_emails_to, $users_emails['member']);
+                        	$purge_user_id_to = array_merge($purge_user_id_to, $users_id['member']);
+                        }
+                        
                         $purge_email_to = join(', ',$users_emails_to );
                         
                         $email_warn.=  "Every user associated with this project received this alert.\n";
-                        if( count($users_emails['administrator']) > 0 ){
+                        if( isset($users_emails['administrator']) && count($users_emails['administrator']) > 0 ){
 							$email_warn.=  " - Administrator(s): ".join(', ',$users_emails['administrator']). "\n";
 						}
-						if( count($users_emails['manager']) > 0 ){
+						if( isset($users_emails['manager']) && count($users_emails['manager']) > 0 ){
 							$email_warn.=  " - Manager(s): ".join(', ',$users_emails['manager']). "\n";
 						}
-						if( count($users_emails['member']) > 0 ){
-							$email_warn.=  " - Members(s): ".join(', ',$users_emails['member']). "\n";
+						if( isset($users_emails['member']) && count($users_emails['member']) > 0 ){
+							$email_warn.=  " - Member(s): ".join(', ',$users_emails['member']). "\n";
                         }
                         
                         //Retrieve purgeable information for email