public string Login([FromBody] Credentials login)// string username, string password)
        {
            // return status or session id
            var player = auth.Authenticate(login.username, login.password);

            if (player != null)
            {
                HttpContext.Session.SetInt32("active", 1);
                HttpContext.Session.CommitAsync();

                // check if a session exists with the username
                // if so, terminate it. cannot be logged in on multiple devices.

                if (sessionManager.TryGetByUsername(login.username, out var existingSession))
                {
                    sessionManager.EndSession(existingSession);
                }

                return(sessionManager.BeginSession(HttpContext.Session.Id, player));
            }

            return(null);
        }