Core/Spells: workaround stealth interaction with Death and Decay and GameObject casts

Closes #10179
Closes #16154

(cherry picked from commit b3a4815067d154fb35da87aa8e7365995d6f65f5)

3 files changed, 24 insertions, 7 deletions

diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index 139fea0ed69..547e0f6d77a 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -7911,7 +7911,8 @@ bool Unit::_IsValidAttackTarget(Unit const* target, SpellInfo const* bySpell, Wo
         return false;
 
     // can't attack invisible (ignore stealth for aoe spells) also if the area being looked at is from a spell use the dynamic object created instead of the casting unit. Ignore stealth if target is player and unit in combat with same player
-    if ((!bySpell || !bySpell->HasAttribute(SPELL_ATTR6_CAN_TARGET_INVISIBLE)) && (obj ? !obj->CanSeeOrDetect(target, bySpell && bySpell->IsAffectingArea(GetMap()->GetDifficultyID())) : !CanSeeOrDetect(target, (bySpell && bySpell->IsAffectingArea(GetMap()->GetDifficultyID())) || (target->GetTypeId() == TYPEID_PLAYER && target->HasStealthAura() && target->IsInCombat() && IsInCombatWith(target)))))
+    // skip visibility check for GO casts, needs removal when go cast is implemented
+    if (GetEntry() != WORLD_TRIGGER && (!bySpell || !bySpell->HasAttribute(SPELL_ATTR6_CAN_TARGET_INVISIBLE)) && (obj ? !obj->CanSeeOrDetect(target, bySpell && bySpell->IsAffectingArea(GetMap()->GetDifficultyID())) : !CanSeeOrDetect(target, (bySpell && bySpell->IsAffectingArea(GetMap()->GetDifficultyID())) || (target->GetTypeId() == TYPEID_PLAYER && target->HasStealthAura() && target->IsInCombat() && IsInCombatWith(target)))))
         return false;
 
     // can't attack dead
diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index a9d2d27b9b0..4e04d91c300 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -2045,11 +2045,15 @@ void Spell::prepareDataForTriggerSystem()
 
     // Hunter trap spells - activation proc for Lock and Load, Entrapment and Misdirection
     if (m_spellInfo->SpellFamilyName == SPELLFAMILY_HUNTER &&
-        (m_spellInfo->SpellFamilyFlags[0] & 0x18 ||     // Freezing and Frost Trap, Freezing Arrow
-        m_spellInfo->Id == 57879 ||                     // Snake Trap - done this way to avoid double proc
-        m_spellInfo->SpellFamilyFlags[2] & 0x00024000)) // Explosive and Immolation Trap
+        (m_spellInfo->SpellFamilyFlags[0] & 0x18 ||         // Freezing and Frost Trap, Freezing Arrow
+            m_spellInfo->Id == 57879 ||                     // Snake Trap - done this way to avoid double proc
+            m_spellInfo->SpellFamilyFlags[2] & 0x00024000)) // Explosive and Immolation Trap
     {
         m_procAttacker |= PROC_FLAG_DONE_TRAP_ACTIVATION;
+
+        // also fill up other flags (DoAllEffectOnTarget only fills up flag if both are not set)
+        m_procAttacker |= PROC_FLAG_DONE_SPELL_MAGIC_DMG_CLASS_NEG;
+        m_procVictim |= PROC_FLAG_TAKEN_SPELL_MAGIC_DMG_CLASS_NEG;
     }
 
     // Hellfire Effect - trigger as DOT
@@ -2108,7 +2112,7 @@ void Spell::AddUnitTarget(Unit* target, uint32 effectMask, bool checkIfValid /*=
         return;
 
     if (checkIfValid)
-        if (m_spellInfo->CheckTarget(m_caster, target, implicit) != SPELL_CAST_OK)
+        if (m_spellInfo->CheckTarget(m_caster, target, implicit || m_caster->GetEntry() == WORLD_TRIGGER) != SPELL_CAST_OK) // skip stealth checks for GO casts
             return;
 
     // Check for effect immune skip if immuned
@@ -4949,14 +4953,18 @@ SpellCastResult Spell::CheckCast(bool strict)
     if (!(m_spellInfo->IsPassive() && (!m_targets.GetUnitTarget() || m_targets.GetUnitTarget() == m_caster)))
     {
         // Check explicit target for m_originalCaster - todo: get rid of such workarounds
-        SpellCastResult castResult = m_spellInfo->CheckExplicitTarget(m_originalCaster ? m_originalCaster : m_caster, m_targets.GetObjectTarget(), m_targets.GetItemTarget());
+        Unit* caster = m_caster;
+        if (m_originalCaster && m_caster->GetEntry() != WORLD_TRIGGER) // Do a simplified check for gameobject casts
+            caster = m_originalCaster;
+
+        SpellCastResult castResult = m_spellInfo->CheckExplicitTarget(caster, m_targets.GetObjectTarget(), m_targets.GetItemTarget());
         if (castResult != SPELL_CAST_OK)
             return castResult;
     }
 
     if (Unit* target = m_targets.GetUnitTarget())
     {
-        SpellCastResult castResult = m_spellInfo->CheckTarget(m_caster, target, false);
+        SpellCastResult castResult = m_spellInfo->CheckTarget(m_caster, target, m_caster->GetEntry() == WORLD_TRIGGER); // skip stealth checks for GO casts
         if (castResult != SPELL_CAST_OK)
             return castResult;
 
diff --git a/src/server/game/Spells/SpellMgr.cpp b/src/server/game/Spells/SpellMgr.cpp
index 31eb2365c1c..03f3f94ce7b 100644
--- a/src/server/game/Spells/SpellMgr.cpp
+++ b/src/server/game/Spells/SpellMgr.cpp
@@ -1462,6 +1462,8 @@ void SpellMgr::LoadSpellProcs()
     isTriggerAura[SPELL_AURA_MOD_ROOT_2] = true;
 
     isAlwaysTriggeredAura[SPELL_AURA_OVERRIDE_CLASS_SCRIPTS] = true;
+    isAlwaysTriggeredAura[SPELL_AURA_MOD_STEALTH] = true;
+    isAlwaysTriggeredAura[SPELL_AURA_MOD_CONFUSE] = true;
     isAlwaysTriggeredAura[SPELL_AURA_MOD_FEAR] = true;
     isAlwaysTriggeredAura[SPELL_AURA_MOD_ROOT] = true;
     isAlwaysTriggeredAura[SPELL_AURA_MOD_STUN] = true;
@@ -2660,6 +2662,12 @@ void SpellMgr::LoadSpellInfoCorrections()
         const_cast<SpellEffectInfo*>(spellInfo->GetEffect(EFFECT_0))->SpellClassMask = flag128(685904631, 1151048, 0, 0);
     });
 
+    // Death and Decay
+    ApplySpellFix({ 52212 }, [](SpellInfo* spellInfo)
+    {
+        spellInfo->AttributesEx6 |= SPELL_ATTR6_CAN_TARGET_INVISIBLE;
+    });
+
     // Oscillation Field
     ApplySpellFix({ 37408 }, [](SpellInfo* spellInfo)
     {