Implement proper paper workaround for initializing viewers of a tracker entry

Avoids trouble down the line...

src/main/generated/com/bergerkiller/generated/net/minecraft/server/level/EntityTrackerEntryHandle.java

@@ -4,7 +4,6 @@ import com.bergerkiller.mountiplex.reflection.declarations.Template;
 import com.bergerkiller.generated.net.minecraft.world.entity.EntityHandle;
 import org.bukkit.entity.Player;
 import java.util.Collection;
-import java.util.List;
 
 /**
  * Instance wrapper handle for type <b>net.minecraft.server.level.EntityTrackerEntry</b>.
@@ -36,7 +35,7 @@ public abstract class EntityTrackerEntryHandle extends Template.Handle {
     public abstract EntityTrackerEntryStateHandle getState();
     public abstract EntityHandle getEntity();
     public abstract void setEntity(EntityHandle entity);
-    public abstract void scanPlayers(List<Player> playerList);
+    public abstract void updateViewers();
     public abstract void removeViewer(Player player);
     public abstract void updatePlayer(Player player);
     public abstract void hideForAll();
@@ -82,7 +81,7 @@ public abstract class EntityTrackerEntryHandle extends Template.Handle {
         public final Template.Method.Converted<Void> setState = new Template.Method.Converted<Void>();
         public final Template.Method.Converted<EntityHandle> getEntity = new Template.Method.Converted<EntityHandle>();
         public final Template.Method.Converted<Void> setEntity = new Template.Method.Converted<Void>();
-        public final Template.Method.Converted<Void> scanPlayers = new Template.Method.Converted<Void>();
+        public final Template.Method<Void> updateViewers = new Template.Method<Void>();
         public final Template.Method.Converted<Void> removeViewer = new Template.Method.Converted<Void>();
         public final Template.Method.Converted<Void> updatePlayer = new Template.Method.Converted<Void>();
         public final Template.Method<Void> hideForAll = new Template.Method<Void>();

src/main/java/com/bergerkiller/bukkit/common/entity/CommonEntity.java

@@ -263,7 +263,7 @@ public class CommonEntity<T extends org.bukkit.entity.Entity> extends ExtendedEn
                 newEntry.updatePlayer(previousViewer);
             }
         } else {
-            newEntry.scanPlayers(getWorld().getPlayers());
+            newEntry.updateViewers();
         }
     }
 

src/main/templates/com/bergerkiller/templates/net/minecraft/server_level_entity_tracker.txt

@@ -299,11 +299,33 @@ class EntityTrackerEntry {
         entry#trackerEntryEntity = entity;
     }
 
+    public void updateViewers() {
+        Entity entity = instance#entity;
+  #if exists net.minecraft.server.level.PlayerChunkMap$EntityTracker final void updatePlayers(com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<net.minecraft.server.level.EntityPlayer> newTrackerCandidates);
+        // Paper after some optimizations were made to tracking
+        #require net.minecraft.server.level.PlayerChunkMap$EntityTracker final void paperUpdatePlayers:updatePlayers(com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<net.minecraft.server.level.EntityPlayer> newTrackerCandidates);
+        com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet players = entity.getPlayersInTrackRange();
+        instance#paperUpdatePlayers(players);
+  #else
+        // Spigot / old paper
+    #if version >= 1.17
+        WorldServer world = (WorldServer) entity.level;
+    #else
+        WorldServer world = (WorldServer) entity.world;
+    #endif
+    #if version >= 1.18
+        java.util.List playersOnWorld = world.players();
+        instance.updatePlayers(playersOnWorld);
+    #else
+        java.util.List playersOnWorld = world.getPlayers();
+        instance.track(playersOnWorld);
+    #endif
+  #endif
+    }
+
   #if version >= 1.18
-    public void scanPlayers:updatePlayers((List<org.bukkit.entity.Player>) List<EntityPlayer> playerList);
     public void removeViewer:removePlayer((org.bukkit.entity.Player) EntityPlayer player);
   #else
-    public void scanPlayers:track((List<org.bukkit.entity.Player>) List<EntityPlayer> playerList);
     public void removeViewer:clear((org.bukkit.entity.Player) EntityPlayer player);
   #endif
 #else
@@ -323,7 +345,15 @@ class EntityTrackerEntry {
         instance#entity = entity;
     }
 
-    public void scanPlayers((List<org.bukkit.entity.Player>) List<EntityHuman> playerList);
+    public void updateViewers() {
+        Entity entity = instance#entity;
+
+        // Spigot / old paper
+        WorldServer world = (WorldServer) entity.world;
+        java.util.List playersOnWorld = world.players;
+        instance.scanPlayers(playersOnWorld);
+    }
+
     public void removeViewer:a((org.bukkit.entity.Player) EntityPlayer player);
 #endif