From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: NONPLAYT <76615486+NONPLAYT@users.noreply.github.com>
Date: Mon, 3 Mar 2025 19:29:13 +0300
Subject: [PATCH] Async Chunk Sending


diff --git a/ca/spottedleaf/moonrise/patches/chunk_system/player/RegionizedPlayerChunkLoader.java b/ca/spottedleaf/moonrise/patches/chunk_system/player/RegionizedPlayerChunkLoader.java
index 78f2d7c698a4f2c21a473627c3017a9751f80cf1..aabfaa370e4bcb8db61e831072b28684482ed938 100644
--- a/ca/spottedleaf/moonrise/patches/chunk_system/player/RegionizedPlayerChunkLoader.java
+++ b/ca/spottedleaf/moonrise/patches/chunk_system/player/RegionizedPlayerChunkLoader.java
@@ -53,6 +53,8 @@ public final class RegionizedPlayerChunkLoader {
     public static final int LOADED_TICKET_LEVEL = ChunkTaskScheduler.getTicketLevel(ChunkStatus.EMPTY);
     public static final int TICK_TICKET_LEVEL = ChunkHolderManager.ENTITY_TICKING_TICKET_LEVEL;
 
+    private static final org.apache.logging.log4j.Logger LOGGER = org.apache.logging.log4j.LogManager.getLogger("RegionizedPlayerChunkLoader"); // DivineMC - Async Chunk Sending
+
     public static final class ViewDistanceHolder {
 
         private volatile ViewDistances viewDistances;
@@ -424,17 +426,61 @@ public final class RegionizedPlayerChunkLoader {
         }
 
         private void sendChunk(final int chunkX, final int chunkZ) {
-            if (this.sentChunks.add(CoordinateUtils.getChunkKey(chunkX, chunkZ))) {
-                ((ChunkSystemChunkHolder)((ChunkSystemServerLevel)this.world).moonrise$getChunkTaskScheduler().chunkHolderManager
-                        .getChunkHolder(chunkX, chunkZ).vanillaChunkHolder).moonrise$addReceivedChunk(this.player);
+            // DivineMC start - Async Chunk Sending
+            final long chunkKey = CoordinateUtils.getChunkKey(chunkX, chunkZ);
+
+            if (!this.sentChunks.add(chunkKey)) return;
 
-                final LevelChunk chunk = ((ChunkSystemLevel)this.world).moonrise$getFullChunkIfLoaded(chunkX, chunkZ);
+            final LevelChunk chunk = ((ChunkSystemLevel) this.world).moonrise$getFullChunkIfLoaded(chunkX, chunkZ);
+            if (chunk == null) {
+                this.sentChunks.remove(chunkKey);
+                return;
+            }
 
+            try {
+                ((ChunkSystemServerLevel) this.world).moonrise$getChunkTaskScheduler().chunkHolderManager.getChunkHolder(chunkX, chunkZ).vanillaChunkHolder.moonrise$addReceivedChunk(this.player);
                 PlatformHooks.get().onChunkWatch(this.world, chunk, this.player);
-                PlayerChunkSender.sendChunk(this.player.connection, this.world, chunk);
+            } catch (IllegalStateException e) {
+                this.sentChunks.remove(chunkKey);
                 return;
             }
-            throw new IllegalStateException();
+
+            if (org.bxteam.divinemc.DivineConfig.asyncChunkSendingEnabled) {
+                net.minecraft.Util.backgroundExecutor().execute(() -> {
+                    try {
+                        // Modified from PlayerChunkSender#sendChunk
+                        final net.minecraft.server.network.ServerGamePacketListenerImpl connection = this.player.connection;
+                        final ServerLevel serverLevel = this.world;
+
+                        final net.minecraft.network.protocol.game.ClientboundLevelChunkWithLightPacket packet = new net.minecraft.network.protocol.game.ClientboundLevelChunkWithLightPacket(
+                            chunk, serverLevel.getLightEngine(), null, null,
+                            serverLevel.chunkPacketBlockController.shouldModify(this.player, chunk)
+                        );
+
+                        serverLevel.getServer().execute(() -> {
+                            if (this.removed || !this.sentChunks.contains(chunkKey)) return;
+
+                            connection.send(packet);
+
+                            if (io.papermc.paper.event.packet.PlayerChunkLoadEvent.getHandlerList().getRegisteredListeners().length > 0) {
+                                new io.papermc.paper.event.packet.PlayerChunkLoadEvent(
+                                    new org.bukkit.craftbukkit.CraftChunk(chunk),
+                                    this.player.getBukkitEntity()
+                                ).callEvent();
+                            }
+
+                            net.minecraft.network.protocol.game.DebugPackets.sendPoiPacketsForChunk(serverLevel, chunk.getPos());
+                        });
+                    } catch (Exception e) {
+                        LOGGER.error("Failed to send chunk asynchronously!", e);
+
+                        if (!this.removed) this.sentChunks.remove(chunkKey);
+                    }
+                });
+            } else {
+                PlayerChunkSender.sendChunk(this.player.connection, this.world, chunk);
+            }
+            // DivineMC end - Async Chunk Sending
         }
 
         private void sendUnloadChunk(final int chunkX, final int chunkZ) {