Core/Creatures: moved summon passive spell casting into SummonInfo API and allow any controlled summon to cast them

src/server/game/DataStores/DBCStores.cpp

@@ -637,10 +637,6 @@ void DBCManager::LoadStores(const std::string& dataPath, uint32 defaultLocale)
         if (!spellInfo)
             continue;
 
-        SpellLevelsEntry const* levels = sSpellLevelsStore.LookupEntry(spellInfo->LevelsID);
-        if (spellInfo->LevelsID && (!levels || levels->SpellLevel))
-            continue;
-
         if (spellInfo && spellInfo->Attributes & SPELL_ATTR0_PASSIVE)
         {
             for (CreatureFamilyEntry const* cFamily : sCreatureFamilyStore)

src/server/game/Entities/Creature/SummonInfo/SummonInfo.cpp

@@ -25,6 +25,7 @@
 #include "Log.h"
 #include "ObjectAccessor.h"
 #include "Player.h"
+#include "SpellMgr.h"
 #include "SummonInfoArgs.h"
 #include "TotemPackets.h"
 
@@ -130,6 +131,8 @@ void SummonInfo::HandlePreSummonActions()
 
         // Totem slot summons always send the TotemCreated packet. Some non-Shaman classes use this
         // to display summon icons that can be canceled (Consecration, DK ghouls, Wild Mushrooms)
+        // This packet must be sent before the creature is being added to the world so that the client
+        // does send correct GUIDs in CMSG_TOTEM_DESTROYED
         switch (slot)
         {
             case SummonPropertiesSlot::Totem1:
@@ -187,6 +190,10 @@ void SummonInfo::HandlePostSummonActions()
         if (_summonedCreature->IsAIEnabled())
             _summonedCreature->AI()->IsSummonedBy(summoner);
     }
+
+    // Casting passive spells
+    if (IsControlledBySummoner())
+        castPassiveSpells();
 }
 
 void SummonInfo::HandlePreUnsummonActions()
@@ -288,3 +295,31 @@ SummonPropertiesControl SummonInfo::GetControl() const
 {
     return _control;
 }
+
+void SummonInfo::castPassiveSpells()
+{
+    CreatureTemplate const* creatureInfo = _summonedCreature->GetCreatureTemplate();
+    if (!creatureInfo)
+        return;
+
+    CreatureFamilyEntry const* creatureFamilyEntry = sCreatureFamilyStore.LookupEntry(creatureInfo->family);
+    if (!creatureFamilyEntry)
+        return;
+
+    auto const petSpellStore = sPetFamilySpellsStore.find(creatureFamilyEntry->ID);
+    if (petSpellStore == sPetFamilySpellsStore.end())
+        return;
+
+    for (uint32 spellId : petSpellStore->second)
+    {
+        if (SpellInfo const* spellInfo = sSpellMgr->GetSpellInfo(spellId))
+        {
+            if (spellInfo->IsPassive())
+            {
+                _summonedCreature->CastSpell(nullptr, spellId);
+                //if (spellInfo->HasAttribute(SPELL_ATTR4_OWNER_POWER_SCALING))
+                //    _scalingAuras.push_back(spellId);
+            }
+        }
+    }
+}

src/server/game/Entities/Creature/SummonInfo/SummonInfo.h

@@ -31,6 +31,15 @@ class Unit;
 
 struct SummonInfoArgs;
 
+/*
+The API for summoned creatures. This class contains all the functionality and features to handle summons
+in a safe manner. However, do not store pointers to SummonInfo instances in scripts as they may change during runtime.
+Instead resort to the accessor methods provided in the Unit class which always return intact instances
+and pointers to both ends of a summon relation:
+- Unit::GetSummonInSlot
+- Unit::GetSummonsByCreatureId
+- Unit::GetSummonsBySpellId
+ */
 class TC_GAME_API SummonInfo
 {
 public:
@@ -93,9 +102,12 @@ public:
     SummonPropertiesControl GetControl() const;
 
 private:
+    // Looks up and casts all passive spells of the creature summon. Often used for scaling auras.
+    void castPassiveSpells();
+
     Creature* _summonedCreature;
     ObjectGuid _summonerGUID;
-    Optional<Milliseconds> _remainingDuration;  // NYI
+    Optional<Milliseconds> _remainingDuration;  // Implemented in SummonInfo::UpdateRemainingDuration
     Optional<uint64> _maxHealth;                // Implemented in Creature::UpdateLevelDependantStats
     Optional<uint32> _factionId;                // Implemented in Creature::UpdateEntry
     Optional<uint8> _creatureLevel;             // Implemented in Creature::SelectLevel