Core: Combat/threat system rewrite (PR #19930)

- PvE combat is now always mutual. UNIT_FLAG_IN_COMBAT is backed by actual references to the units we're in combat with.
- PvP combat is now also tracked, and almost always mutual; spells like Vanish and Feign Death can break this rule. That means we can easily determine a list of players we're fighting.
- By extension, IsInCombatWith now has sensible behavior when invoked on nonplayers.
- Threat and combat systems are no longer the same.
  - They still have an enforced relationship (threat implies combat - clearing combat clears threat)...
  - ...but we can have combat without threat. A creature (with threat list) isn't considered to be engaged until it has an entry on its threat list...
  - ...which means we can now faithfully replicate retail engage behavior. Combat on projectile launch - engagement start on projectile impact. Yay for progress!
- AI method refactor, as already ported in 6113b9d - `JustEngagedWith`, `JustEnteredCombat` and `JustExitedCombat`.
- Vehicle threat is now properly pooled on the main vehicle body (fixes #16542).
- Various edge case bug fixes for threat redirects (Misdirection "cancelling" Vigilance and similar).
- Target re-selection is now significantly faster.
- Fixed a ton of other smaller edge case bugs, probably.

Closes #7951 and #19998.

(cherry picked from commit 532ab1c7f8653d1a2e48aa1f1f8a9ba1041d4bb7)

2 files changed, 73 insertions, 25 deletions

diff --git a/src/server/scripts/Commands/cs_debug.cpp b/src/server/scripts/Commands/cs_debug.cpp
index 15372bc0882..b46b8cfd978 100644
--- a/src/server/scripts/Commands/cs_debug.cpp
+++ b/src/server/scripts/Commands/cs_debug.cpp
@@ -846,23 +846,73 @@ public:
 
     static bool HandleDebugThreatListCommand(ChatHandler* handler, char const* /*args*/)
     {
-        Creature* target = handler->getSelectedCreature();
-        if (!target || target->IsTotem() || target->IsPet())
-            return false;
+        Unit* target = handler->getSelectedUnit();
+        if (!target)
+            target = handler->GetSession()->GetPlayer();
+        
+        ThreatManager& mgr = target->GetThreatManager();
+        if (!target->IsAlive())
+        {
+            handler->PSendSysMessage("%s (%s) is not alive.", target->GetName().c_str(), target->GetGUID().ToString().c_str());
+            return true;
+        }
+        if (!target->CanHaveThreatList())
+            handler->PSendSysMessage("%s (%s) cannot have a threat list.", target->GetName().c_str(), target->GetGUID().ToString().c_str());
 
-        ThreatContainer::StorageType const& threatList = target->GetThreatManager().getThreatList();
-        ThreatContainer::StorageType::const_iterator itr;
         uint32 count = 0;
-        handler->PSendSysMessage("Threat list of %s (%s)", target->GetName().c_str(), target->GetGUID().ToString().c_str());
-        for (itr = threatList.begin(); itr != threatList.end(); ++itr)
+        auto const& threatenedByMe = target->GetThreatManager().GetThreatenedByMeList();
+        if (threatenedByMe.empty())
+            handler->PSendSysMessage("%s (%s) does not threaten any units.", target->GetName().c_str(), target->GetGUID().ToString().c_str());
+        else
         {
-            Unit* unit = (*itr)->getTarget();
-            if (!unit)
-                continue;
-            ++count;
-            handler->PSendSysMessage("   %u.   %s   (%s)  - threat %f", count, unit->GetName().c_str(), unit->GetGUID().ToString().c_str(), (*itr)->getThreat());
+            handler->PSendSysMessage("List of units threatened by %s (%s)", target->GetName().c_str(), target->GetGUID().ToString().c_str());
+            for (auto const& pair : threatenedByMe)
+            {
+                Unit* unit = pair.second->GetOwner();
+                handler->PSendSysMessage("   %u.   %s   (%s, SpawnID %u)  - threat %f", ++count, unit->GetName().c_str(), unit->GetGUID().ToString().c_str(), unit->GetTypeId() == TYPEID_UNIT ? unit->ToCreature()->GetSpawnId() : 0, pair.second->GetThreat());
+            }
+            handler->SendSysMessage("End of threatened-by-me list.");
         }
-        handler->SendSysMessage("End of threat list.");
+
+        if (!mgr.CanHaveThreatList())
+            return true;
+        if (mgr.IsEngaged())
+        {
+            count = 0;
+            handler->PSendSysMessage("Threat list of %s (%s, SpawnID %u)", target->GetName().c_str(), target->GetGUID().ToString().c_str(), target->GetTypeId() == TYPEID_UNIT ? target->ToCreature()->GetSpawnId() : 0);
+            for (ThreatReference const* ref : mgr.GetSortedThreatList())
+            {
+                Unit* unit = ref->GetVictim();
+                char const* onlineStr;
+                switch (ref->GetOnlineState())
+                {
+                    case ThreatReference::ONLINE_STATE_SUPPRESSED:
+                        onlineStr = " [SUPPRESSED]";
+                        break;
+                    case ThreatReference::ONLINE_STATE_OFFLINE:
+                        onlineStr = " [OFFLINE]";
+                        break;
+                    default:
+                        onlineStr = "";
+                }
+                char const* tauntStr;
+                switch (ref->GetTauntState())
+                {
+                    case ThreatReference::TAUNT_STATE_TAUNT:
+                        tauntStr = " [TAUNT]";
+                        break;
+                    case ThreatReference::TAUNT_STATE_DETAUNT:
+                        tauntStr = " [DETAUNT]";
+                        break;
+                    default:
+                        tauntStr = "";
+                }
+                handler->PSendSysMessage("   %u.   %s   (%s)  - threat %f%s%s", ++count, unit->GetName().c_str(), unit->GetGUID().ToString().c_str(), ref->GetThreat(), tauntStr, onlineStr);
+            }
+            handler->SendSysMessage("End of threat list.");
+        }
+        else
+            handler->PSendSysMessage("%s (%s, SpawnID %u) is not currently engaged.", target->GetName().c_str(), target->GetGUID().ToString().c_str(), target->GetTypeId() == TYPEID_UNIT ? target->ToCreature()->GetSpawnId() : 0);
         return true;
     }
 
@@ -871,19 +921,18 @@ public:
         Unit* target = handler->getSelectedUnit();
         if (!target)
             target = handler->GetSession()->GetPlayer();
-        HostileReference* ref = target->getHostileRefManager().getFirst();
-        uint32 count = 0;
-        handler->PSendSysMessage("Hostil reference list of %s (%s)", target->GetName().c_str(), target->GetGUID().ToString().c_str());
-        while (ref)
+
+        handler->PSendSysMessage("Combat refs: (Combat state: %d | Manager state: %d)", target->IsInCombat(), target->GetCombatManager().HasCombat());
+        for (auto const& ref : target->GetCombatManager().GetPvPCombatRefs())
         {
-            if (Unit* unit = ref->GetSource()->GetOwner())
-            {
-                ++count;
-                handler->PSendSysMessage("   %u.   %s   (%s, SpawnId: %s)  - threat %f", count, unit->GetName().c_str(), unit->GetGUID().ToString().c_str(), unit->GetTypeId() == TYPEID_UNIT ? std::to_string(unit->ToCreature()->GetSpawnId()).c_str() : "0", ref->getThreat());
-            }
-            ref = ref->next();
+            Unit* unit = ref.second->GetOther(target);
+            handler->PSendSysMessage("[PvP] %s (SpawnID %u)", unit->GetName().c_str(), unit->GetTypeId() == TYPEID_UNIT ? unit->ToCreature()->GetSpawnId() : 0);
+        }
+        for (auto const& ref : target->GetCombatManager().GetPvECombatRefs())
+        {
+            Unit* unit = ref.second->GetOther(target);
+            handler->PSendSysMessage("[PvE] %s (SpawnID %u)", unit->GetName().c_str(), unit->GetTypeId() == TYPEID_UNIT ? unit->ToCreature()->GetSpawnId() : 0);
         }
-        handler->SendSysMessage("End of hostil reference list.");
         return true;
     }
 
diff --git a/src/server/scripts/Commands/cs_misc.cpp b/src/server/scripts/Commands/cs_misc.cpp
index 0b3547670bc..c8fe798fcaf 100644
--- a/src/server/scripts/Commands/cs_misc.cpp
+++ b/src/server/scripts/Commands/cs_misc.cpp
@@ -2491,7 +2491,6 @@ public:
             return false;
 
         target->CombatStop();
-        target->getHostileRefManager().deleteReferences();
         return true;
     }