private void HandleAddAdmin(ChatUser user, string[] parts)
{
if (parts.Length == 1)
{
throw new InvalidOperationException("Who do you want to make an admin?");
}
string targetUserName = parts[1];
ChatUser targetUser = _repository.VerifyUser(targetUserName);
_chatService.AddAdmin(user, targetUser);
_notificationService.AddAdmin(targetUser);
_repository.CommitChanges();
}