fix: Visionİnformation ignoring flashed, severedeyes and blindness (#846)

* fix

* remove magic number

* i forgot update comment l'ne

* Update VisionInformationFix.cs

Author: MS-crew

EXILED/Exiled.Events/Patches/Fixes/VisionInformationFix.cs

@@ -0,0 +1,81 @@
+// -----------------------------------------------------------------------
+// <copyright file="VisionInformationFix.cs" company="ExMod Team">
+// Copyright (c) ExMod Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+namespace Exiled.Events.Patches.Fixes
+{
+    using System.Collections.Generic;
+    using System.Reflection.Emit;
+
+    using API.Features.Pools;
+
+    using CustomPlayerEffects;
+
+    using HarmonyLib;
+
+    using PlayerRoles.PlayableScps;
+
+    using static HarmonyLib.AccessTools;
+
+    /// <summary>
+    /// Patches <see cref="VisionInformation.CheckIsInDarkness"/>.
+    /// Fix for effects that blind the player are not perceived as blindness.
+    /// Bug reported to NW (https://git.scpslgame.com/northwood-qa/scpsl-bug-reporting/-/issues/3125).
+    /// </summary>
+    [HarmonyPatch(typeof(VisionInformation), nameof(VisionInformation.CheckIsInDarkness))]
+    internal class VisionInformationFix
+    {
+        private static IEnumerable<CodeInstruction> Transpiler(IEnumerable<CodeInstruction> instructions, ILGenerator generator)
+        {
+            List<CodeInstruction> newInstructions = ListPool<CodeInstruction>.Pool.Get(instructions);
+
+            LocalBuilder effectsController = generator.DeclareLocal(typeof(PlayerEffectsController));
+
+            Label retTrue = generator.DefineLabel();
+            Label @continue = generator.DefineLabel();
+
+            newInstructions[0].labels.Add(@continue);
+
+            newInstructions.InsertRange(0, new CodeInstruction[]
+            {
+                // effectsController = hub.playerEffectsController;
+                new(OpCodes.Ldarg_0),
+                new(OpCodes.Ldfld, Field(typeof(ReferenceHub), nameof(ReferenceHub.playerEffectsController))),
+                new(OpCodes.Dup),
+                new(OpCodes.Stloc_S, effectsController),
+
+                // if (effectsController.GetEffect<Flashed>().IsEnabled)
+                //     return true;
+                new(OpCodes.Callvirt, Method(typeof(PlayerEffectsController), nameof(PlayerEffectsController.GetEffect)).MakeGenericMethod(typeof(Flashed))),
+                new(OpCodes.Callvirt, PropertyGetter(typeof(Flashed), nameof(Flashed.IsEnabled))),
+                new(OpCodes.Brtrue_S, retTrue),
+
+                // if (effectsController.GetEffect<SeveredEyes>().IsEnabled)
+                //     return true;
+                new(OpCodes.Ldloc_S, effectsController),
+                new(OpCodes.Callvirt, Method(typeof(PlayerEffectsController), nameof(PlayerEffectsController.GetEffect)).MakeGenericMethod(typeof(SeveredEyes))),
+                new(OpCodes.Callvirt, PropertyGetter(typeof(SeveredEyes), nameof(SeveredEyes.IsEnabled))),
+                new(OpCodes.Brtrue_S, retTrue),
+
+                // if (effectsController.GetEffect<Blindness>().Intensity >= Blindness.MaxHealableIntensity)
+                //     return true;
+                new(OpCodes.Ldloc_S, effectsController),
+                new(OpCodes.Callvirt, Method(typeof(PlayerEffectsController), nameof(PlayerEffectsController.GetEffect)).MakeGenericMethod(typeof(Blindness))),
+                new(OpCodes.Callvirt, PropertyGetter(typeof(Blindness), nameof(Blindness.Intensity))),
+                new(OpCodes.Ldc_I4, (int)Blindness.MaxHealableIntensity),
+                new(OpCodes.Bge_S, retTrue),
+
+                new(OpCodes.Br_S, @continue),
+                new CodeInstruction(OpCodes.Ldc_I4_1).WithLabels(retTrue),
+                new(OpCodes.Ret),
+            });
+
+            for (int z = 0; z < newInstructions.Count; z++)
+                yield return newInstructions[z];
+
+            ListPool<CodeInstruction>.Pool.Return(newInstructions);
+        }
+    }
+}