Core/Combat Improve extra attacks handling

Port From (https://github.com/TrinityCore/TrinityCore/commit/6c9bde098b40f38905ea7407d0cd77437b0b953c)

Source/Game/Spells/Auras/AuraEffect.cs

@@ -645,8 +645,16 @@ namespace Game.Spells
                     uint triggerSpellId = GetSpellEffectInfo().TriggerSpell;
                     SpellInfo triggeredSpellInfo = Global.SpellMgr.GetSpellInfo(triggerSpellId, GetBase().GetCastDifficulty());
                     if (triggeredSpellInfo != null)
-                        if (aurApp.GetTarget().ExtraAttacks != 0 && triggeredSpellInfo.HasEffect(SpellEffectName.AddExtraAttacks))
-                            return false;
+                    {
+                        if (triggeredSpellInfo.HasEffect(SpellEffectName.AddExtraAttacks))
+                        {
+                            uint lastExtraAttackSpell = eventInfo.GetActor().GetLastExtraAttackSpell();
+
+                            // Patch 1.12.0(?) extra attack abilities can no longer chain proc themselves
+                            if (lastExtraAttackSpell == triggerSpellId)
+                                return false;
+                        }
+                    }
                     break;
                 }
                 case AuraType.ModSpellCritChance:

Source/Game/Spells/Spell.cs

@@ -140,7 +140,7 @@ namespace Game.Spells
         void InitExplicitTargets(SpellCastTargets targets)
         {
             m_targets = targets;
-            m_targets.SetOrigUnitTarget(m_targets.GetUnitTarget());
+
             // this function tries to correct spell explicit targets for spell
             // client doesn't send explicit targets correctly sometimes - we need to fix such spells serverside
             // this also makes sure that we correctly send explicit targets to client (removes redundant data)
@@ -3132,14 +3132,8 @@ namespace Game.Spells
                 if (m_comboPointGain != 0)
                     unitCaster.AddComboPoints(m_comboPointGain);
 
-                if (unitCaster.ExtraAttacks != 0 && m_spellInfo.HasEffect(SpellEffectName.AddExtraAttacks))
-                {
-                    Unit victim = Global.ObjAccessor.GetUnit(unitCaster, m_targets.GetOrigUnitTargetGUID());
-                    if (victim)
-                        unitCaster.HandleProcExtraAttackFor(victim);
-                    else
-                        unitCaster.ExtraAttacks = 0;
-                }
+                if (m_spellInfo.HasEffect(SpellEffectName.AddExtraAttacks))
+                    unitCaster.SetLastExtraAttackSpell(m_spellInfo.Id);
             }
 
             // Handle procs on finish
@@ -8337,6 +8331,8 @@ namespace Game.Spells
                     }
                     else
                     {
+                        caster.SetLastDamagedTargetGuid(spell.unitTarget.GetGUID());
+
                         // Add bonuses and fill damageInfo struct
                         caster.CalculateSpellDamageTaken(damageInfo, spell.m_damage, spell.m_spellInfo, spell.m_attackType, IsCrit);
                         Unit.DealDamageMods(damageInfo.attacker, damageInfo.target, ref damageInfo.damage, ref damageInfo.absorb);

Source/Game/Spells/SpellCastTargets.cs

@@ -114,28 +114,6 @@ namespace Game.Spells
                 data.Name = m_strTarget;
         }
 
-        public ObjectGuid GetOrigUnitTargetGUID()
-        {
-            switch (m_origObjectTargetGUID.GetHigh())
-            {
-                case HighGuid.Player:
-                case HighGuid.Vehicle:
-                case HighGuid.Creature:
-                case HighGuid.Pet:
-                    return m_origObjectTargetGUID;
-                default:
-                    return ObjectGuid.Empty;
-            }
-        }
-
-        public void SetOrigUnitTarget(Unit target)
-        {
-            if (!target)
-                return;
-
-            m_origObjectTargetGUID = target.GetGUID();
-        }
-
         public ObjectGuid GetUnitTargetGUID()
         {
             if (m_objectTargetGUID.IsUnit())
@@ -420,7 +398,6 @@ namespace Game.Spells
         Item m_itemTarget;
 
         // object GUID/etc, can be used always
-        ObjectGuid m_origObjectTargetGUID;
         ObjectGuid m_objectTargetGUID;
         ObjectGuid m_itemTargetGUID;
         uint m_itemTargetEntry;

Source/Game/Spells/SpellEffects.cs

@@ -3487,10 +3487,7 @@ namespace Game.Spells
             if (!unitTarget || !unitTarget.IsAlive())
                 return;
 
-            if (unitTarget.ExtraAttacks != 0)
-                return;
-
-            unitTarget.ExtraAttacks = (uint)damage;
+            unitTarget.AddExtraAttacks((uint)damage);
 
             ExecuteLogEffectExtraAttacks(effectInfo.Effect, unitTarget, (uint)damage);
         }