Fix splash skip on epic

Reactor/Patches/SplashSkip.cs

@@ -1,4 +1,7 @@
+using System.Reflection;
 using HarmonyLib;
+using System;
+using MonoMod.Utils;
 
 namespace Reactor.Patches
 {
@@ -10,4 +13,23 @@ private static void Prefix(SplashManager __instance)
             __instance.minimumSecondsBeforeSceneChange = 0;
         }
     }
+
+    [HarmonyPatch(typeof(SplashManager), nameof(SplashManager.Update))]
+    internal static class WaitForEpicAuth
+    {
+        private static readonly PropertyInfo? _localUserIdProperty = typeof(EpicManager).GetProperty("localUserId", BindingFlags.Static | BindingFlags.Public);
+        private static readonly Func<object>? _localUserId = _localUserIdProperty == null ? null : _localUserIdProperty.GetMethod.CreateDelegate<Func<object>>();
+
+        private static bool Prefix(SplashManager __instance)
+        {
+            if (__instance.startedSceneLoad) return true;
+
+            if (_localUserId != null && _localUserId() == null)
+            {
+                return false;
+            }
+
+            return true;
+        }
+    }
 }