quantum-space-buddies/EpicRerouter/ExeSide/EpicEntitlementRetriever.cs

using Epic.OnlineServices;
using Epic.OnlineServices.Ecom;
using System;
using static EntitlementsManager;

namespace EpicRerouter.ExeSide
{
	public static class EpicEntitlementRetriever
	{
		private const string _eosDlcItemID = "49a9ac61fe464cbf8c8c73f46b3f1133";

		private static EcomInterface _ecomInterface;
		private static OwnershipStatus _epicDlcOwnershipStatus;
		private static bool _epicResultReceived;

		public static void Init() =>
			EpicPlatformManager.OnAuthSuccess += EOSQueryOwnership;

		public static void Uninit() =>
			EpicPlatformManager.OnAuthSuccess -= EOSQueryOwnership;

		public static AsyncOwnershipStatus GetOwnershipStatus()
		{
			if (!_epicResultReceived)
			{
				return AsyncOwnershipStatus.NotReady;
			}

			return _epicDlcOwnershipStatus == OwnershipStatus.Owned ?
				AsyncOwnershipStatus.Owned : AsyncOwnershipStatus.NotOwned;
		}

		private static void EOSQueryOwnership()
		{
			Console.WriteLine("[EOS] querying DLC ownership");
			_ecomInterface = EpicPlatformManager.PlatformInterface.GetEcomInterface();
			var queryOwnershipOptions = new QueryOwnershipOptions
			{
				LocalUserId = EpicPlatformManager.LocalUserId,
				CatalogItemIds = new[] { _eosDlcItemID }
			};
			_ecomInterface.QueryOwnership(queryOwnershipOptions, null, OnEOSQueryOwnershipComplete);
		}

		private static void OnEOSQueryOwnershipComplete(QueryOwnershipCallbackInfo data)
		{
			if (data.ResultCode == Result.Success)
			{
				_epicDlcOwnershipStatus = data.ItemOwnership[0].OwnershipStatus;
				_epicResultReceived = true;
				Console.WriteLine($"[EOS] Query DLC ownership complete: {_epicDlcOwnershipStatus}");
			}
		}
	}
}