Core/SAI: Allow SMART_TARGET_ACTION_INVOKER to target GameObjects (#24416)

* Core/SAI: Allow SMART_TARGET_ACTION_INVOKER to target GameObjects

* Include new Coalesce(..) template by @Shauren

3 files changed, 19 insertions, 7 deletions

diff --git a/src/common/Utilities/Util.h b/src/common/Utilities/Util.h
index 4915df56477..866e01e7bf6 100644
--- a/src/common/Utilities/Util.h
+++ b/src/common/Utilities/Util.h
@@ -519,4 +519,16 @@ constexpr typename std::underlying_type<E>::type AsUnderlyingType(E enumValue)
     return static_cast<typename std::underlying_type<E>::type>(enumValue);
 }
 
+template<typename Ret, typename Only>
+Ret* Coalesce(Only* arg)
+{
+    return arg;
+}
+
+template<typename Ret, typename T1, typename... T>
+Ret* Coalesce(T1* first, T*... rest)
+{
+    return static_cast<Ret*>(first ? static_cast<Ret*>(first) : Coalesce<Ret>(rest...));
+}
+
 #endif
diff --git a/src/server/game/AI/SmartScripts/SmartScript.cpp b/src/server/game/AI/SmartScripts/SmartScript.cpp
index a12095a3ec0..dcd3f7124a3 100644
--- a/src/server/game/AI/SmartScripts/SmartScript.cpp
+++ b/src/server/game/AI/SmartScripts/SmartScript.cpp
@@ -243,7 +243,7 @@ void SmartScript::ProcessAction(SmartScriptHolder& e, Unit* unit, uint32 var0, u
         TC_LOG_DEBUG("scripts.ai", "SmartScript::ProcessAction: Invoker: %s %s", tempInvoker->GetName().c_str(), tempInvoker->GetGUID().ToString().c_str());
 
     ObjectVector targets;
-    GetTargets(targets, e, unit);
+    GetTargets(targets, e, Coalesce<WorldObject>(unit, gob));
 
     switch (e.GetActionType())
     {
@@ -2468,9 +2468,9 @@ SmartScriptHolder SmartScript::CreateSmartEvent(SMART_EVENT e, uint32 event_flag
     return script;
 }
 
-void SmartScript::GetTargets(ObjectVector& targets, SmartScriptHolder const& e, Unit* invoker /*= nullptr*/) const
+void SmartScript::GetTargets(ObjectVector& targets, SmartScriptHolder const& e, WorldObject* invoker /*= nullptr*/) const
 {
-    Unit* scriptTrigger = nullptr;
+    WorldObject* scriptTrigger = nullptr;
     if (invoker)
         scriptTrigger = invoker;
     else if (Unit* tempLastInvoker = GetLastInvoker())
@@ -2548,8 +2548,8 @@ void SmartScript::GetTargets(ObjectVector& targets, SmartScriptHolder const& e,
                 targets.push_back(scriptTrigger);
             break;
         case SMART_TARGET_ACTION_INVOKER_VEHICLE:
-            if (scriptTrigger && scriptTrigger->GetVehicle() && scriptTrigger->GetVehicle()->GetBase())
-                targets.push_back(scriptTrigger->GetVehicle()->GetBase());
+            if (scriptTrigger && scriptTrigger->ToUnit() && scriptTrigger->ToUnit()->GetVehicle() && scriptTrigger->ToUnit()->GetVehicle()->GetBase())
+                targets.push_back(scriptTrigger->ToUnit()->GetVehicle()->GetBase());
             break;
         case SMART_TARGET_INVOKER_PARTY:
             if (scriptTrigger)
@@ -3086,7 +3086,7 @@ void SmartScript::ProcessEvent(SmartScriptHolder& e, Unit* unit, uint32 var0, ui
                 (!e.event.spellHit.school || (spell->SchoolMask & e.event.spellHit.school)))
                 {
                     RecalcTimer(e, e.event.spellHit.cooldownMin, e.event.spellHit.cooldownMax);
-                    ProcessAction(e, unit, 0, 0, bvar, spell);
+                    ProcessAction(e, unit, 0, 0, bvar, spell, gob);
                 }
             break;
         }
diff --git a/src/server/game/AI/SmartScripts/SmartScript.h b/src/server/game/AI/SmartScripts/SmartScript.h
index 7b01f3ee26e..fe8db54a8a5 100644
--- a/src/server/game/AI/SmartScripts/SmartScript.h
+++ b/src/server/game/AI/SmartScripts/SmartScript.h
@@ -47,7 +47,7 @@ class TC_GAME_API SmartScript
         static void InitTimer(SmartScriptHolder& e);
         void ProcessAction(SmartScriptHolder& e, Unit* unit = nullptr, uint32 var0 = 0, uint32 var1 = 0, bool bvar = false, SpellInfo const* spell = nullptr, GameObject* gob = nullptr);
         void ProcessTimedAction(SmartScriptHolder& e, uint32 const& min, uint32 const& max, Unit* unit = nullptr, uint32 var0 = 0, uint32 var1 = 0, bool bvar = false, SpellInfo const* spell = nullptr, GameObject* gob = nullptr);
-        void GetTargets(ObjectVector& targets, SmartScriptHolder const& e, Unit* invoker = nullptr) const;
+        void GetTargets(ObjectVector& targets, SmartScriptHolder const& e, WorldObject* invoker = nullptr) const;
         void GetWorldObjectsInDist(ObjectVector& objects, float dist) const;
         void InstallTemplate(SmartScriptHolder const& e);
         static SmartScriptHolder CreateSmartEvent(SMART_EVENT e, uint32 event_flags, uint32 event_param1, uint32 event_param2, uint32 event_param3, uint32 event_param4, uint32 event_param5, SMART_ACTION action, uint32 action_param1, uint32 action_param2, uint32 action_param3, uint32 action_param4, uint32 action_param5, uint32 action_param6, SMARTAI_TARGETS t, uint32 target_param1, uint32 target_param2, uint32 target_param3, uint32 target_param4, uint32 phaseMask);