Gamesparks sdk +unity sdk user management

GameSparks,FB unity integraion.cs

using System;
using UnityEngine;

using System.Collections.Generic;
using GameSparks.Api;
using GameSparks.Api.Messages;
using GameSparks.Api.Requests;
using GameSparks.Api.Responses;
using GameSparks.Core;
using Facebook;


namespace MyApp
{
	public class UserManager : MonoBehaviour
	{
		public UserManager ()
		{
		}
		// Tries to silently log in user if already logged in before in another gaming session 
		public void Awake(){
			if (!FB.IsInitialized) {
				FB.Init (()=>{});
			} else {
				if (FB.IsLoggedIn) LoginFacebook();
			}
		}

		// initiates the action to login to facebook and forwards login to gamesparks.
		// it is async and uses callback style instead of return value
		public void LoginFacebook(Action<UserDetails> success = null, Action<FBResult> error=null){
			if (FB.IsLoggedIn) {
				FacebookUserLoggedIn(null,success,error);
			}else{
				FB.Login("email,user_friends", (result)=>{
					FacebookUserLoggedIn(result,success,error);
				});
			}
		}

		private void FacebookUserLoggedIn(FBResult result=null,Action<UserDetails> success=null, Action<FBResult> error=null){
			if(result !=null && result.Error != null){
				Debug.Log("Error logging in to facebook");
				if(error!=null)error(result);
			}else{
				new FacebookConnectRequest().SetAccessToken(FB.AccessToken).Send((response) => {
					Debug.Log("OK! fb connected");
					var userDetails = new UserDetails();
					userDetails.id = response.UserId;
					if(success!=null) success(userDetails);
				});
			}
		}
	}
}