PaperMC/paper-server/patches/sources/net/minecraft/server/level/ChunkMap.java.patch

--- a/net/minecraft/server/level/ChunkMap.java
+++ b/net/minecraft/server/level/ChunkMap.java
@@ -104,6 +104,10 @@
 import org.apache.commons.lang3.mutable.MutableBoolean;
 import org.slf4j.Logger;
 
+// CraftBukkit start
+import org.bukkit.craftbukkit.generator.CustomChunkGenerator;
+// CraftBukkit end
+
 public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider, GeneratingChunkMap {
 
     private static final ChunkResult<List<ChunkAccess>> UNLOADED_CHUNK_LIST_RESULT = ChunkResult.error("Unloaded chunks found in range");
@@ -149,6 +153,33 @@
     public int serverViewDistance;
     private final WorldGenContext worldGenContext;
 
+    // CraftBukkit start - recursion-safe executor for Chunk loadCallback() and unloadCallback()
+    public final CallbackExecutor callbackExecutor = new CallbackExecutor();
+    public static final class CallbackExecutor implements java.util.concurrent.Executor, Runnable {
+
+        private final java.util.Queue<Runnable> queue = new java.util.ArrayDeque<>();
+
+        @Override
+        public void execute(Runnable runnable) {
+            this.queue.add(runnable);
+        }
+
+        @Override
+        public void run() {
+            Runnable task;
+            while ((task = this.queue.poll()) != null) {
+                task.run();
+            }
+        }
+    };
+    // CraftBukkit end
+
+    // Paper start
+    public final ChunkHolder getUnloadingChunkHolder(int chunkX, int chunkZ) {
+        return this.pendingUnloads.get(ca.spottedleaf.moonrise.common.util.CoordinateUtils.getChunkKey(chunkX, chunkZ));
+    }
+    // Paper end
+
     public ChunkMap(ServerLevel world, LevelStorageSource.LevelStorageAccess session, DataFixer dataFixer, StructureTemplateManager structureTemplateManager, Executor executor, BlockableEventLoop<Runnable> mainThreadExecutor, LightChunkGetter chunkProvider, ChunkGenerator chunkGenerator, ChunkProgressListener worldGenerationProgressListener, ChunkStatusUpdateListener chunkStatusChangeListener, Supplier<DimensionDataStorage> persistentStateManagerFactory, int viewDistance, boolean dsync) {
         super(new RegionStorageInfo(session.getLevelId(), world.dimension(), "chunk"), session.getDimensionPath(world.dimension()).resolve("region"), dataFixer, dsync);
         this.visibleChunkMap = this.updatingChunkMap.clone();
@@ -170,13 +201,19 @@
         RegistryAccess iregistrycustom = world.registryAccess();
         long j = world.getSeed();
 
-        if (chunkGenerator instanceof NoiseBasedChunkGenerator chunkgeneratorabstract) {
+        // CraftBukkit start - SPIGOT-7051: It's a rigged game! Use delegate for random state creation, otherwise it is not so random.
+        ChunkGenerator randomGenerator = chunkGenerator;
+        if (randomGenerator instanceof CustomChunkGenerator customChunkGenerator) {
+            randomGenerator = customChunkGenerator.getDelegate();
+        }
+        if (randomGenerator instanceof NoiseBasedChunkGenerator chunkgeneratorabstract) {
+            // CraftBukkit end
             this.randomState = RandomState.create((NoiseGeneratorSettings) chunkgeneratorabstract.generatorSettings().value(), (HolderGetter) iregistrycustom.lookupOrThrow(Registries.NOISE), j);
         } else {
             this.randomState = RandomState.create(NoiseGeneratorSettings.dummy(), (HolderGetter) iregistrycustom.lookupOrThrow(Registries.NOISE), j);
         }
 
-        this.chunkGeneratorState = chunkGenerator.createState(iregistrycustom.lookupOrThrow(Registries.STRUCTURE_SET), this.randomState, j);
+        this.chunkGeneratorState = chunkGenerator.createState(iregistrycustom.lookupOrThrow(Registries.STRUCTURE_SET), this.randomState, j, world.spigotConfig); // Spigot
         this.mainThreadExecutor = mainThreadExecutor;
         ConsecutiveExecutor consecutiveexecutor = new ConsecutiveExecutor(executor, "worldgen");
 
@@ -198,6 +235,12 @@
         this.chunksToEagerlySave.add(pos.toLong());
     }
 
+    // Paper start
+    public int getMobCountNear(final ServerPlayer player, final net.minecraft.world.entity.MobCategory mobCategory) {
+        return -1;
+    }
+    // Paper end
+
     protected ChunkGenerator generator() {
         return this.worldGenContext.generator();
     }
@@ -325,7 +368,7 @@
                         throw this.debugFuturesAndCreateReportedException(new IllegalStateException("At least one of the chunk futures were null"), "n/a");
                     }
 
-                    ChunkAccess ichunkaccess = (ChunkAccess) chunkresult.orElse((Object) null);
+                    ChunkAccess ichunkaccess = (ChunkAccess) chunkresult.orElse(null); // CraftBukkit - decompile error
 
                     if (ichunkaccess == null) {
                         return ChunkMap.UNLOADED_CHUNK_LIST_RESULT;
@@ -354,9 +397,9 @@
         };
 
         stringbuilder.append("Updating:").append(System.lineSeparator());
-        this.updatingChunkMap.values().forEach(consumer);
+        ca.spottedleaf.moonrise.common.util.ChunkSystem.getUpdatingChunkHolders(this.level).forEach(consumer); // Paper
         stringbuilder.append("Visible:").append(System.lineSeparator());
-        this.visibleChunkMap.values().forEach(consumer);
+        ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolders(this.level).forEach(consumer); // Paper
         CrashReport crashreport = CrashReport.forThrowable(exception, "Chunk loading");
         CrashReportCategory crashreportsystemdetails = crashreport.addCategory("Chunk loading");
 
@@ -398,6 +441,9 @@
                     holder.setTicketLevel(level);
                 } else {
                     holder = new ChunkHolder(new ChunkPos(pos), level, this.level, this.lightEngine, this::onLevelChange, this);
+                    // Paper start
+                    ca.spottedleaf.moonrise.common.util.ChunkSystem.onChunkHolderCreate(this.level, holder);
+                    // Paper end
                 }
 
                 this.updatingChunkMap.put(pos, holder);
@@ -427,7 +473,7 @@
 
     protected void saveAllChunks(boolean flush) {
         if (flush) {
-            List<ChunkHolder> list = this.visibleChunkMap.values().stream().filter(ChunkHolder::wasAccessibleSinceLastSave).peek(ChunkHolder::refreshAccessibility).toList();
+            List<ChunkHolder> list = ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolders(this.level).stream().filter(ChunkHolder::wasAccessibleSinceLastSave).peek(ChunkHolder::refreshAccessibility).toList(); // Paper
             MutableBoolean mutableboolean = new MutableBoolean();
 
             do {
@@ -453,7 +499,7 @@
         } else {
             this.nextChunkSaveTime.clear();
             long i = Util.getMillis();
-            ObjectIterator objectiterator = this.visibleChunkMap.values().iterator();
+            Iterator<ChunkHolder> objectiterator = ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolders(this.level).iterator(); // Paper
 
             while (objectiterator.hasNext()) {
                 ChunkHolder playerchunk = (ChunkHolder) objectiterator.next();
@@ -478,7 +524,7 @@
     }
 
     public boolean hasWork() {
-        return this.lightEngine.hasLightWork() || !this.pendingUnloads.isEmpty() || !this.updatingChunkMap.isEmpty() || this.poiManager.hasWork() || !this.toDrop.isEmpty() || !this.unloadQueue.isEmpty() || this.worldgenTaskDispatcher.hasWork() || this.lightTaskDispatcher.hasWork() || this.distanceManager.hasTickets();
+        return this.lightEngine.hasLightWork() || !this.pendingUnloads.isEmpty() || ca.spottedleaf.moonrise.common.util.ChunkSystem.hasAnyChunkHolders(this.level) || !this.updatingChunkMap.isEmpty() || this.poiManager.hasWork() || !this.toDrop.isEmpty() || !this.unloadQueue.isEmpty() || this.worldgenTaskDispatcher.hasWork() || this.lightTaskDispatcher.hasWork() || this.distanceManager.hasTickets();
     }
 
     private void processUnloads(BooleanSupplier shouldKeepTicking) {
@@ -537,8 +583,11 @@
                 this.scheduleUnload(pos, chunk);
             } else {
                 ChunkAccess ichunkaccess = chunk.getLatestChunk();
-
-                if (this.pendingUnloads.remove(pos, chunk) && ichunkaccess != null) {
+                // Paper start
+                boolean removed;
+                if ((removed = this.pendingUnloads.remove(pos, chunk)) && ichunkaccess != null) {
+                    ca.spottedleaf.moonrise.common.util.ChunkSystem.onChunkHolderDelete(this.level, chunk);
+                    // Paper end
                     LevelChunk chunk1;
 
                     if (ichunkaccess instanceof LevelChunk) {
@@ -556,7 +605,9 @@
                     this.lightEngine.tryScheduleUpdate();
                     this.progressListener.onStatusChange(ichunkaccess.getPos(), (ChunkStatus) null);
                     this.nextChunkSaveTime.remove(ichunkaccess.getPos().toLong());
-                }
+                } else if (removed) { // Paper start
+                    ca.spottedleaf.moonrise.common.util.ChunkSystem.onChunkHolderDelete(this.level, chunk);
+                } // Paper end
 
             }
         };
@@ -905,7 +956,7 @@
         }
     }
 
-    protected void setServerViewDistance(int watchDistance) {
+    public void setServerViewDistance(int watchDistance) { // Paper - public
         int j = Mth.clamp(watchDistance, 2, 32);
 
         if (j != this.serverViewDistance) {
@@ -922,7 +973,7 @@
 
     }
 
-    int getPlayerViewDistance(ServerPlayer player) {
+    public int getPlayerViewDistance(ServerPlayer player) { // Paper - public
         return Mth.clamp(player.requestedViewDistance(), 2, this.serverViewDistance);
     }
 
@@ -951,7 +1002,7 @@
     }
 
     public int size() {
-        return this.visibleChunkMap.size();
+        return ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolderCount(this.level); // Paper
     }
 
     public DistanceManager getDistanceManager() {
@@ -959,25 +1010,26 @@
     }
 
     protected Iterable<ChunkHolder> getChunks() {
-        return Iterables.unmodifiableIterable(this.visibleChunkMap.values());
+        return Iterables.unmodifiableIterable(ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolders(this.level)); // Paper
     }
 
     void dumpChunks(Writer writer) throws IOException {
         CsvOutput csvwriter = CsvOutput.builder().addColumn("x").addColumn("z").addColumn("level").addColumn("in_memory").addColumn("status").addColumn("full_status").addColumn("accessible_ready").addColumn("ticking_ready").addColumn("entity_ticking_ready").addColumn("ticket").addColumn("spawning").addColumn("block_entity_count").addColumn("ticking_ticket").addColumn("ticking_level").addColumn("block_ticks").addColumn("fluid_ticks").build(writer);
         TickingTracker tickingtracker = this.distanceManager.tickingTracker();
-        ObjectBidirectionalIterator objectbidirectionaliterator = this.visibleChunkMap.long2ObjectEntrySet().iterator();
+        Iterator<ChunkHolder> objectbidirectionaliterator = ca.spottedleaf.moonrise.common.util.ChunkSystem.getVisibleChunkHolders(this.level).iterator(); // Paper
 
         while (objectbidirectionaliterator.hasNext()) {
-            Entry<ChunkHolder> entry = (Entry) objectbidirectionaliterator.next();
-            long i = entry.getLongKey();
+            ChunkHolder playerchunk = objectbidirectionaliterator.next(); // Paper
+            long i = playerchunk.pos.toLong(); // Paper
             ChunkPos chunkcoordintpair = new ChunkPos(i);
-            ChunkHolder playerchunk = (ChunkHolder) entry.getValue();
+            // Paper - move up
             Optional<ChunkAccess> optional = Optional.ofNullable(playerchunk.getLatestChunk());
             Optional<LevelChunk> optional1 = optional.flatMap((ichunkaccess) -> {
                 return ichunkaccess instanceof LevelChunk ? Optional.of((LevelChunk) ichunkaccess) : Optional.empty();
             });
 
-            csvwriter.writeRow(chunkcoordintpair.x, chunkcoordintpair.z, playerchunk.getTicketLevel(), optional.isPresent(), optional.map(ChunkAccess::getPersistedStatus).orElse((Object) null), optional1.map(LevelChunk::getFullStatus).orElse((Object) null), ChunkMap.printFuture(playerchunk.getFullChunkFuture()), ChunkMap.printFuture(playerchunk.getTickingChunkFuture()), ChunkMap.printFuture(playerchunk.getEntityTickingChunkFuture()), this.distanceManager.getTicketDebugString(i), this.anyPlayerCloseEnoughForSpawning(chunkcoordintpair), optional1.map((chunk) -> {
+            // CraftBukkit - decompile error
+            csvwriter.writeRow(chunkcoordintpair.x, chunkcoordintpair.z, playerchunk.getTicketLevel(), optional.isPresent(), optional.map(ChunkAccess::getPersistedStatus).orElse(null), optional1.map(LevelChunk::getFullStatus).orElse(null), ChunkMap.printFuture(playerchunk.getFullChunkFuture()), ChunkMap.printFuture(playerchunk.getTickingChunkFuture()), ChunkMap.printFuture(playerchunk.getEntityTickingChunkFuture()), this.distanceManager.getTicketDebugString(i), this.anyPlayerCloseEnoughForSpawning(chunkcoordintpair), optional1.map((chunk) -> {
                 return chunk.getBlockEntities().size();
             }).orElse(0), tickingtracker.getTicketDebugString(i), tickingtracker.getLevel(i), optional1.map((chunk) -> {
                 return chunk.getBlockTicks().count();
@@ -990,7 +1042,7 @@
 
     private static String printFuture(CompletableFuture<ChunkResult<LevelChunk>> future) {
         try {
-            ChunkResult<LevelChunk> chunkresult = (ChunkResult) future.getNow((Object) null);
+            ChunkResult<LevelChunk> chunkresult = (ChunkResult) future.getNow(null); // CraftBukkit - decompile error
 
             return chunkresult != null ? (chunkresult.isSuccess() ? "done" : "unloaded") : "not completed";
         } catch (CompletionException completionexception) {
@@ -1002,12 +1054,14 @@
 
     private CompletableFuture<Optional<CompoundTag>> readChunk(ChunkPos chunkPos) {
         return this.read(chunkPos).thenApplyAsync((optional) -> {
-            return optional.map(this::upgradeChunkTag);
+            return optional.map((nbttagcompound) -> this.upgradeChunkTag(nbttagcompound, chunkPos)); // CraftBukkit
         }, Util.backgroundExecutor().forName("upgradeChunk"));
     }
 
-    private CompoundTag upgradeChunkTag(CompoundTag nbt) {
-        return this.upgradeChunkTag(this.level.dimension(), this.overworldDataStorage, nbt, this.generator().getTypeNameForDataFixer());
+    // CraftBukkit start
+    private CompoundTag upgradeChunkTag(CompoundTag nbttagcompound, ChunkPos chunkcoordintpair) {
+        return this.upgradeChunkTag(this.level.getTypeKey(), this.overworldDataStorage, nbttagcompound, this.generator().getTypeNameForDataFixer(), chunkcoordintpair, this.level);
+        // CraftBukkit end
     }
 
     void forEachSpawnCandidateChunk(Consumer<ChunkHolder> callback) {
@@ -1025,10 +1079,23 @@
     }
 
     public boolean anyPlayerCloseEnoughForSpawning(ChunkPos pos) {
-        return !this.distanceManager.hasPlayersNearby(pos.toLong()) ? false : this.anyPlayerCloseEnoughForSpawningInternal(pos);
+        // Spigot start
+        return this.anyPlayerCloseEnoughForSpawning(pos, false);
     }
 
+    boolean anyPlayerCloseEnoughForSpawning(ChunkPos chunkcoordintpair, boolean reducedRange) {
+        return !this.distanceManager.hasPlayersNearby(chunkcoordintpair.toLong()) ? false : this.anyPlayerCloseEnoughForSpawningInternal(chunkcoordintpair, reducedRange);
+        // Spigot end
+    }
+
     private boolean anyPlayerCloseEnoughForSpawningInternal(ChunkPos pos) {
+        // Spigot start
+        return this.anyPlayerCloseEnoughForSpawningInternal(pos, false);
+    }
+
+    private boolean anyPlayerCloseEnoughForSpawningInternal(ChunkPos chunkcoordintpair, boolean reducedRange) {
+        double blockRange; // Paper - use from event
+        // Spigot end
         Iterator iterator = this.playerMap.getAllPlayers().iterator();
 
         ServerPlayer entityplayer;
@@ -1039,7 +1106,16 @@
             }
 
             entityplayer = (ServerPlayer) iterator.next();
-        } while (!this.playerIsCloseEnoughForSpawning(entityplayer, pos));
+            // Paper start - PlayerNaturallySpawnCreaturesEvent
+            com.destroystokyo.paper.event.entity.PlayerNaturallySpawnCreaturesEvent event;
+            blockRange = 16384.0D;
+            if (reducedRange) {
+                event = entityplayer.playerNaturallySpawnedEvent;
+                if (event == null || event.isCancelled()) continue;
+                blockRange = (double) ((event.getSpawnRadius() << 4) * (event.getSpawnRadius() << 4));
+            }
+            // Paper end - PlayerNaturallySpawnCreaturesEvent
+        } while (!this.playerIsCloseEnoughForSpawning(entityplayer, chunkcoordintpair, blockRange)); // Spigot
 
         return true;
     }
@@ -1056,7 +1132,7 @@
             while (iterator.hasNext()) {
                 ServerPlayer entityplayer = (ServerPlayer) iterator.next();
 
-                if (this.playerIsCloseEnoughForSpawning(entityplayer, pos)) {
+                if (this.playerIsCloseEnoughForSpawning(entityplayer, pos, 16384.0D)) { // Spigot
                     builder.add(entityplayer);
                 }
             }
@@ -1065,13 +1141,13 @@
         }
     }
 
-    private boolean playerIsCloseEnoughForSpawning(ServerPlayer player, ChunkPos pos) {
-        if (player.isSpectator()) {
+    private boolean playerIsCloseEnoughForSpawning(ServerPlayer entityplayer, ChunkPos chunkcoordintpair, double range) { // Spigot
+        if (entityplayer.isSpectator()) {
             return false;
         } else {
-            double d0 = ChunkMap.euclideanDistanceSquared(pos, player);
+            double d0 = ChunkMap.euclideanDistanceSquared(chunkcoordintpair, entityplayer);
 
-            return d0 < 16384.0D;
+            return d0 < range; // Spigot
         }
     }
 
@@ -1215,9 +1291,19 @@
     }
 
     public void addEntity(Entity entity) {
+        org.spigotmc.AsyncCatcher.catchOp("entity track"); // Spigot
+        // Paper start - ignore and warn about illegal addEntity calls instead of crashing server
+        if (!entity.valid || entity.level() != this.level || this.entityMap.containsKey(entity.getId())) {
+            LOGGER.error("Illegal ChunkMap::addEntity for world " + this.level.getWorld().getName()
+                + ": " + entity  + (this.entityMap.containsKey(entity.getId()) ? " ALREADY CONTAINED (This would have crashed your server)" : ""), new Throwable());
+            return;
+        }
+        // Paper end - ignore and warn about illegal addEntity calls instead of crashing server
+        if (entity instanceof ServerPlayer && ((ServerPlayer) entity).supressTrackerForLogin) return; // Paper - Fire PlayerJoinEvent when Player is actually ready; Delay adding to tracker until after list packets
         if (!(entity instanceof EnderDragonPart)) {
             EntityType<?> entitytypes = entity.getType();
             int i = entitytypes.clientTrackingRange() * 16;
+            i = org.spigotmc.TrackingRange.getEntityTrackingRange(entity, i); // Spigot
 
             if (i != 0) {
                 int j = entitytypes.updateInterval();
@@ -1250,6 +1336,7 @@
     }
 
     protected void removeEntity(Entity entity) {
+        org.spigotmc.AsyncCatcher.catchOp("entity untrack"); // Spigot
         if (entity instanceof ServerPlayer entityplayer) {
             this.updatePlayerStatus(entityplayer, false);
             ObjectIterator objectiterator = this.entityMap.values().iterator();
@@ -1391,7 +1478,7 @@
         });
     }
 
-    private class ChunkDistanceManager extends DistanceManager {
+    public class ChunkDistanceManager extends DistanceManager { // Paper - public
 
         protected ChunkDistanceManager(final Executor workerExecutor, final Executor mainThreadExecutor) {
             super(workerExecutor, mainThreadExecutor);
@@ -1424,7 +1511,7 @@
         public final Set<ServerPlayerConnection> seenBy = Sets.newIdentityHashSet();
 
         public TrackedEntity(final Entity entity, final int i, final int j, final boolean flag) {
-            this.serverEntity = new ServerEntity(ChunkMap.this.level, entity, j, flag, this::broadcast);
+            this.serverEntity = new ServerEntity(ChunkMap.this.level, entity, j, flag, this::broadcast, this.seenBy); // CraftBukkit
             this.entity = entity;
             this.range = i;
             this.lastSectionPos = SectionPos.of((EntityAccess) entity);
@@ -1469,6 +1556,7 @@
         }
 
         public void removePlayer(ServerPlayer player) {
+            org.spigotmc.AsyncCatcher.catchOp("player tracker clear"); // Spigot
             if (this.seenBy.remove(player.connection)) {
                 this.serverEntity.removePairing(player);
             }
@@ -1476,6 +1564,7 @@
         }
 
         public void updatePlayer(ServerPlayer player) {
+            org.spigotmc.AsyncCatcher.catchOp("player tracker update"); // Spigot
             if (player != this.entity) {
                 Vec3 vec3d = player.position().subtract(this.entity.position());
                 int i = ChunkMap.this.getPlayerViewDistance(player);
@@ -1484,6 +1573,11 @@
                 double d2 = d0 * d0;
                 boolean flag = d1 <= d2 && this.entity.broadcastToPlayer(player) && ChunkMap.this.isChunkTracked(player, this.entity.chunkPosition().x, this.entity.chunkPosition().z);
 
+                // CraftBukkit start - respect vanish API
+                if (!player.getBukkitEntity().canSee(this.entity.getBukkitEntity())) {
+                    flag = false;
+                }
+                // CraftBukkit end
                 if (flag) {
                     if (this.seenBy.add(player.connection)) {
                         this.serverEntity.addPairing(player);
@@ -1506,6 +1600,7 @@
             while (iterator.hasNext()) {
                 Entity entity = (Entity) iterator.next();
                 int j = entity.getType().clientTrackingRange() * 16;
+                j = org.spigotmc.TrackingRange.getEntityTrackingRange(entity, j); // Paper
 
                 if (j > i) {
                     i = j;