1 files changed, 27 insertions, 12 deletions

diff --git a/src/server/game/Handlers/SpellHandler.cpp b/src/server/game/Handlers/SpellHandler.cpp
index c0d115e755f..b05c972faf9 100644
--- a/src/server/game/Handlers/SpellHandler.cpp
+++ b/src/server/game/Handlers/SpellHandler.cpp
@@ -330,6 +330,7 @@ void WorldSession::HandleCastSpellOpcode(WorldPacket& recvPacket)
     uint32 spellId;
     uint8  castCount, castFlags;
     recvPacket >> castCount >> spellId >> castFlags;
+    TriggerCastFlags triggerFlag = TRIGGERED_NONE;
 
     TC_LOG_DEBUG("network", "WORLD: got cast spell packet, castCount: %u, spellId: %u, castFlags: %u, data length = %u", castCount, spellId, castFlags, (uint32)recvPacket.size());
 
@@ -369,24 +370,38 @@ void WorldSession::HandleCastSpellOpcode(WorldPacket& recvPacket)
         caster = _player;
     }
 
+    // client provided targets
+    SpellCastTargets targets;
+    targets.Read(recvPacket, caster);
+    HandleClientCastFlags(recvPacket, castFlags, targets);
+
+    // not have spell in spellbook
     if (caster->GetTypeId() == TYPEID_PLAYER && !caster->ToPlayer()->HasActiveSpell(spellId))
     {
-        // not have spell in spellbook
-        recvPacket.rfinish(); // prevent spam at ignore packet
-        return;
+        bool allow = false;
+
+        // allow casting of unknown spells for special lock cases
+        if (GameObject *go = targets.GetGOTarget())
+            if (go->GetSpellForLock(caster->ToPlayer()) == spellInfo)
+                allow = true;
+
+        // TODO: Preparation for #23204
+        // allow casting of spells triggered by clientside periodic trigger auras
+        /*
+         if (caster->HasAuraTypeWithTriggerSpell(SPELL_AURA_PERIODIC_TRIGGER_SPELL_FROM_CLIENT, spellId))
+        {
+            allow = true;
+            triggerFlag = TRIGGERED_FULL_MASK;
+        }
+        */
+
+        if (!allow)
+            return;
     }
 
     // can't use our own spells when we're in possession of another unit,
     if (_player->isPossessing())
-    {
-        recvPacket.rfinish(); // prevent spam at ignore packet
         return;
-    }
-
-    // client provided targets
-    SpellCastTargets targets;
-    targets.Read(recvPacket, caster);
-    HandleClientCastFlags(recvPacket, castFlags, targets);
 
     // Client is resending autoshot cast opcode when other spell is cast during shoot rotation
     // Skip it to prevent "interrupt" message
@@ -415,7 +430,7 @@ void WorldSession::HandleCastSpellOpcode(WorldPacket& recvPacket)
                 spellInfo = actualSpellInfo;
         }
 
-    Spell* spell = new Spell(caster, spellInfo, TRIGGERED_NONE);
+    Spell* spell = new Spell(caster, spellInfo, triggerFlag);
     spell->m_cast_count = castCount;                       // set count of casts
     spell->prepare(targets);
 }