DeadDropSystem: check lifecycle and null refs on compromise. (new-fro…

…ntiers-14#2251)

* DeadDropSystem: compromise checks teardown

* DeadDropSystem: check teardown

Content.Server/_NF/Smuggling/DeadDropSystem.cs

@@ -195,11 +195,18 @@ private void OnStationShutdown(EntityUid stationUid, StationDeadDropComponent co
 
     public void CompromiseDeadDrop(EntityUid uid, DeadDropComponent _)
     {
-        //Get our station: FIXME - check lifecycle on entities before adding another drop.
+        // Remove the dead drop.
+        RemComp<DeadDropComponent>(uid);
+
         var station = _station.GetOwningStation(uid);
+        // If station is terminating, or if we aren't on one, nothing to do here.
+        if (station == null ||
+            !station.Value.Valid ||
+            MetaData(station.Value).EntityLifeStage >= EntityLifeStage.Terminating)
+        {
+            return;
+        }
 
-        //Remove the dead drop.
-        RemComp<DeadDropComponent>(uid);
         //Find a new potential dead drop to spawn.
         var deadDropQuery = EntityManager.EntityQueryEnumerator<PotentialDeadDropComponent>();
         List<(EntityUid ent, PotentialDeadDropComponent comp)> potentialDeadDrops = new();
@@ -220,6 +227,12 @@ public void CompromiseDeadDrop(EntityUid uid, DeadDropComponent _)
         if (potentialDeadDrops.Count > 0)
         {
             var item = _random.Pick(potentialDeadDrops);
+
+            // If the item is tearing down, do nothing for now.
+            // FIXME: separate sector-wide scheduler?
+            if (MetaData(item.ent).EntityLifeStage >= EntityLifeStage.Terminating)
+                return;
+
             AddDeadDrop(item.ent);
             _sawmill.Debug($"Dead drop at {uid} compromised, new drop at {item.ent}!");
         }