Properly stop attacking after player leaves ffa area (like Gurubashi Arena) (#18952)

src/server/game/Entities/Player/Player.cpp

@@ -7060,9 +7060,14 @@ void Player::UpdateArea(uint32 newArea)
     m_areaUpdateId = newArea;
 
     AreaTableEntry const* area = sAreaTableStore.LookupEntry(newArea);
+    bool oldFFAPvPArea = pvpInfo.IsInFFAPvPArea;
     pvpInfo.IsInFFAPvPArea = area && (area->flags & AREA_FLAG_ARENA);
     UpdatePvPState(true);
 
+    // check if we were in ffa arena and we left
+    if (oldFFAPvPArea && !pvpInfo.IsInFFAPvPArea)
+        ValidateAttackersAndOwnTarget();
+
     UpdateAreaDependentAuras(newArea);
 
     // previously this was in UpdateZone (but after UpdateArea) so nothing will break

src/server/game/Entities/Unit/Unit.cpp

@@ -5874,6 +5874,24 @@ bool Unit::AttackStop()
     return true;
 }
 
+void Unit::ValidateAttackersAndOwnTarget()
+{
+    // iterate attackers
+    UnitVector toRemove;
+    AttackerSet const& attackers = getAttackers();
+    for (Unit* attacker : attackers)
+        if (!attacker->IsValidAttackTarget(this))
+            toRemove.push_back(attacker);
+
+    for (Unit* attacker : toRemove)
+        attacker->AttackStop();
+
+    // remove our own victim
+    if (Unit* victim = GetVictim())
+        if (!IsValidAttackTarget(victim))
+            AttackStop();
+}
+
 void Unit::CombatStop(bool includingCast)
 {
     if (includingCast && IsNonMeleeSpellCast(false))

src/server/game/Entities/Unit/Unit.h

@@ -1264,6 +1264,7 @@ class TC_GAME_API Unit : public WorldObject
     public:
         typedef std::set<Unit*> AttackerSet;
         typedef std::set<Unit*> ControlList;
+        typedef std::vector<Unit*> UnitVector;
 
         typedef std::multimap<uint32, Aura*> AuraMap;
         typedef std::pair<AuraMap::const_iterator, AuraMap::const_iterator> AuraMapBounds;
@@ -1340,6 +1341,7 @@ class TC_GAME_API Unit : public WorldObject
             return m_attacking;
         }
 
+        void ValidateAttackersAndOwnTarget();
         void CombatStop(bool includingCast = false);
         void CombatStopWithPets(bool includingCast = false);
         void StopAttackFaction(uint32 faction_id);