Core/Creature: implement school immunity for creatures in creature_template (#20709)

4 files changed, 31 insertions, 7 deletions

diff --git a/src/server/game/Entities/Creature/Creature.cpp b/src/server/game/Entities/Creature/Creature.cpp
index 7fda65686ed..49f2f7d977a 100644
--- a/src/server/game/Entities/Creature/Creature.cpp
+++ b/src/server/game/Entities/Creature/Creature.cpp
@@ -613,6 +613,7 @@ bool Creature::UpdateEntry(uint32 entry, CreatureData const* data /*= nullptr*/,
     UpdateMovementFlags();
     LoadCreaturesAddon();
     LoadMechanicTemplateImmunity();
+    LoadSpellTemplateImmunity();
     return true;
 }
 
@@ -2056,6 +2057,26 @@ void Creature::LoadMechanicTemplateImmunity()
     }
 }
 
+void Creature::LoadSpellTemplateImmunity()
+{
+    // uint32 max used for "spell id", the immunity system will not perform SpellInfo checks against invalid spells
+    // used so we know which immunities were loaded from template
+    static uint32 const placeholderSpellId = std::numeric_limits<uint32>::max();
+
+    // unapply template immunities (in case we're updating entry)
+    for (uint8 i = SPELL_SCHOOL_NORMAL; i <= SPELL_SCHOOL_ARCANE; ++i)
+        ApplySpellImmune(placeholderSpellId, IMMUNITY_SCHOOL, i, false);
+
+    // don't inherit immunities for hunter pets
+    if (GetOwnerGUID().IsPlayer() && IsHunterPet())
+        return;
+
+    if (uint8 mask = GetCreatureTemplate()->SpellSchoolImmuneMask)
+        for (uint8 i = SPELL_SCHOOL_NORMAL; i <= SPELL_SCHOOL_ARCANE; ++i)
+            if (mask & (1 << i))
+                ApplySpellImmune(placeholderSpellId, IMMUNITY_SCHOOL, 1 << i, true);
+}
+
 bool Creature::IsImmunedToSpell(SpellInfo const* spellInfo, Unit* caster) const
 {
     if (!spellInfo)
diff --git a/src/server/game/Entities/Creature/Creature.h b/src/server/game/Entities/Creature/Creature.h
index 731b0bf5627..148bfe6ab16 100644
--- a/src/server/game/Entities/Creature/Creature.h
+++ b/src/server/game/Entities/Creature/Creature.h
@@ -107,6 +107,7 @@ class TC_GAME_API Creature : public Unit, public GridObject<Creature>, public Ma
         bool isCanTrainingAndResetTalentsOf(Player* player) const;
         bool CanCreatureAttack(Unit const* victim, bool force = true) const;
         void LoadMechanicTemplateImmunity();
+        void LoadSpellTemplateImmunity();
         bool IsImmunedToSpell(SpellInfo const* spellInfo, Unit* caster) const override;
         bool IsImmunedToSpellEffect(SpellInfo const* spellInfo, uint32 index, Unit* caster) const override;
         bool isElite() const;
diff --git a/src/server/game/Entities/Creature/CreatureData.h b/src/server/game/Entities/Creature/CreatureData.h
index f9ae6f24850..ef0bb7b59a4 100644
--- a/src/server/game/Entities/Creature/CreatureData.h
+++ b/src/server/game/Entities/Creature/CreatureData.h
@@ -144,6 +144,7 @@ struct TC_GAME_API CreatureTemplate
     uint32  movementId;
     bool    RegenHealth;
     uint32  MechanicImmuneMask;
+    uint8   SpellSchoolImmuneMask;
     uint32  flags_extra;
     uint32  ScriptID;
     WorldPacket QueryData[TOTAL_LOCALES];
diff --git a/src/server/game/Globals/ObjectMgr.cpp b/src/server/game/Globals/ObjectMgr.cpp
index ddcc9e7cae4..69470e119c6 100644
--- a/src/server/game/Globals/ObjectMgr.cpp
+++ b/src/server/game/Globals/ObjectMgr.cpp
@@ -414,8 +414,8 @@ void ObjectMgr::LoadCreatureTemplates()
                                              "spell2, spell3, spell4, spell5, spell6, spell7, spell8, PetSpellDataId, VehicleId, mingold, maxgold, AIName, MovementType, "
     //                                        62           63           64              65            66             67              68                  69
                                              "InhabitType, HoverHeight, HealthModifier, ManaModifier, ArmorModifier, DamageModifier, ExperienceModifier, RacialLeader, "
-    //                                             70          71                72               73          74
-                                             "movementId, RegenHealth, mechanic_immune_mask, flags_extra, ScriptName "
+    //                                        70          71           72                    73                        74           75
+                                             "movementId, RegenHealth, mechanic_immune_mask, spell_school_immune_mask, flags_extra, ScriptName "
                                              "FROM creature_template;");
 
     if (!result)
@@ -511,11 +511,12 @@ void ObjectMgr::LoadCreatureTemplate(Field* fields)
     creatureTemplate.ModExperience  = fields[68].GetFloat();
     creatureTemplate.RacialLeader   = fields[69].GetBool();
 
-    creatureTemplate.movementId         = fields[70].GetUInt32();
-    creatureTemplate.RegenHealth        = fields[71].GetBool();
-    creatureTemplate.MechanicImmuneMask = fields[72].GetUInt32();
-    creatureTemplate.flags_extra        = fields[73].GetUInt32();
-    creatureTemplate.ScriptID           = GetScriptId(fields[74].GetString());
+    creatureTemplate.movementId            = fields[70].GetUInt32();
+    creatureTemplate.RegenHealth           = fields[71].GetBool();
+    creatureTemplate.MechanicImmuneMask    = fields[72].GetUInt32();
+    creatureTemplate.SpellSchoolImmuneMask = fields[73].GetUInt8();
+    creatureTemplate.flags_extra           = fields[74].GetUInt32();
+    creatureTemplate.ScriptID              = GetScriptId(fields[75].GetString());
 }
 
 void ObjectMgr::LoadCreatureTemplateAddons()