Role Based Filtration

In my Lookup it must show only those contacts who have Specific role.

Example:

Contact-1 , Contact-2 are present

Contact-1 Have Role-1 and contact-2 will have Role-2

Lookup must show only Contacts with Role-1 . 

If not possible Can we have workaround for this .

In my Example it will show all contacts who are system users.

for these i want to filter collection based on role.

I tried this Please let me know the changes needed.

"lookupListConfig": {

                    // Array of filters used for the query that forms the lookup field data.

                    "filters": [

                        function() {

                            var filterGroup = Ext.create("Terrasoft.FilterGroup");

                            // Adding the "IsUser" filter to the resulting filters collection.

                            // The filter provides for the selection of all records in the Contact core schema

                            // to which the Id column from the SysAdminUnit schema is connected, for which

                            // Id is not equal to null.

                            filterGroup.add("IsUser",

                                Terrasoft.createColumnIsNotNullFilter("[SysAdminUnit:Contact].Id"));

                                                        // Adding the "IsActive" filter to the resultant filters collection.

                            // The filter provides for the selection of all records from the core schema.

                            // Contact to which the Id column from the SysAdminUnit schema, for which

                            // Active=true, is connected.

                            filterGroup.add("IsActive",

                                Terrasoft.createColumnFilterWithParameter(

                                    Terrasoft.ComparisonType.EQUAL,

                                    "[SysAdminUnit:Contact].Active",

                                    true));

                            return filterGroup;

                        }

                    ]

                }

            }