From aa5994f457b2178e9153a7020be0150900a9b9f6 Mon Sep 17 00:00:00 2001
From: hondacrx <prelude_20032002@yahoo.com>
Date: Sun, 26 Sep 2021 14:23:30 -0400
Subject: [PATCH] Core/Threat: Re-add fixate system. I am being told
 Netherspite needs it.

Port From (https://github.com/TrinityCore/TrinityCore/commit/16eb5032ad0e8fbc9cd9d3229be65a8f0190347b)
---
 Source/Game/Chat/Commands/DebugCommands.cs |  3 +-
 Source/Game/Combat/ThreatManager.cs        | 33 +++++++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/Source/Game/Chat/Commands/DebugCommands.cs b/Source/Game/Chat/Commands/DebugCommands.cs
index 04d0fafd2..fdee92923 100644
--- a/Source/Game/Chat/Commands/DebugCommands.cs
+++ b/Source/Game/Chat/Commands/DebugCommands.cs
@@ -933,10 +933,11 @@ namespace Game.Chat
                         handler.SendSysMessage($"{target.GetName()} ({target.GetGUID()}, SpawnID {(target.IsCreature() ? target.ToCreature().GetSpawnId() : 0)}) is not engaged, but still has a threat list? Well, here it is:");
 
                     count = 0;
+                    Unit fixateVictim = mgr.GetFixateTarget();
                     foreach (ThreatReference refe in mgr.GetSortedThreatList())
                     {
                         Unit unit = refe.GetVictim();
-                        handler.SendSysMessage($"   {++count}.   {unit.GetName()}   ({unit.GetGUID()})  - threat {refe.GetThreat()}[{refe.GetTauntState()}][{refe.GetOnlineState()}]");
+                        handler.SendSysMessage($"   {++count}.   {unit.GetName()}   ({unit.GetGUID()})  - threat {refe.GetThreat()}[{(unit == fixateVictim ? "FIXATE" : refe.GetTauntState())}][{refe.GetOnlineState()}]");
                     }
                     handler.SendSysMessage("End of threat list.");
                 }
diff --git a/Source/Game/Combat/ThreatManager.cs b/Source/Game/Combat/ThreatManager.cs
index 7fb845902..964cf6226 100644
--- a/Source/Game/Combat/ThreatManager.cs
+++ b/Source/Game/Combat/ThreatManager.cs
@@ -37,6 +37,7 @@ namespace Game.Combat
         List<ThreatReference> _sortedThreatList = new();
         Dictionary<ObjectGuid, ThreatReference> _myThreatListEntries = new();
         ThreatReference _currentVictimRef;
+        ThreatReference _fixateRef;
 
         Dictionary<ObjectGuid, ThreatReference> _threatenedByMe = new(); // these refs are entries for myself on other units' threat lists
         public float[] _singleSchoolModifiers = new float[(int)SpellSchools.Max]; // most spells are single school - we pre-calculate these and store them
@@ -387,10 +388,38 @@ namespace Game.Combat
             while (!_myThreatListEntries.Empty());
         }
 
+        public void FixateTarget(Unit target)
+        {
+            if (target)
+            {
+                var it = _myThreatListEntries.LookupByKey(target.GetGUID());
+                if (it != null)
+                {
+                    _fixateRef = it;
+                    return;
+                }
+            }
+            _fixateRef = null;
+        }
+
+        public Unit GetFixateTarget()
+        {
+            if (_fixateRef != null)
+                return _fixateRef.GetVictim();
+            else
+                return null;
+        }
+
+        public void ClearFixate() { FixateTarget(null); }
+
         ThreatReference ReselectVictim()
         {
+            // fixated target is always preferred
+            if (_fixateRef != null && _fixateRef.IsAvailable())
+                return _fixateRef;
+
             ThreatReference oldVictimRef = _currentVictimRef;
-            if (oldVictimRef != null && !oldVictimRef.IsAvailable())
+            if (oldVictimRef != null && oldVictimRef.IsOffline())
                 oldVictimRef = null;
 
             // in 99% of cases - we won't need to actually look at anything beyond the first element
@@ -640,6 +669,8 @@ namespace Game.Combat
 
             if (_currentVictimRef == refe)
                 _currentVictimRef = null;
+            if (_fixateRef == refe)
+                _fixateRef = null;
 
             _sortedThreatList.Remove(refe);
             _sortedThreatList.Sort();