implement hacky Bukkit structure workaround

platforms/bukkit/src/main/java/com/dfsek/terra/bukkit/nms/NMSChunkGeneratorDelegate.java

@@ -3,9 +3,7 @@ package com.dfsek.terra.bukkit.nms;
 import com.dfsek.terra.api.config.ConfigPack;
 import com.dfsek.terra.api.world.biome.generation.BiomeProvider;
 import com.dfsek.terra.api.world.info.WorldProperties;
-import com.dfsek.terra.bukkit.generator.BukkitProtoChunk;
 import com.dfsek.terra.bukkit.world.BukkitAdapter;
-import com.dfsek.terra.bukkit.world.BukkitServerWorld;
 
 import com.mojang.serialization.Codec;
 import net.minecraft.core.BlockPosition;
@@ -25,7 +23,8 @@ import net.minecraft.world.level.levelgen.WorldGenStage;
 import net.minecraft.world.level.levelgen.blending.Blender;
 import org.bukkit.craftbukkit.v1_18_R2.CraftWorld;
 import org.bukkit.craftbukkit.v1_18_R2.block.data.CraftBlockData;
-import org.bukkit.craftbukkit.v1_18_R2.generator.CraftChunkData;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
@@ -33,7 +32,7 @@ import java.util.concurrent.Executor;
 
 
 public class NMSChunkGeneratorDelegate extends ChunkGenerator {
-    
+    private static final Logger LOGGER = LoggerFactory.getLogger(ChunkGenerator.class);
     private final NMSBiomeProvider biomeSource;
     private final com.dfsek.terra.api.world.chunk.generation.ChunkGenerator delegate;
     
@@ -41,6 +40,8 @@ public class NMSChunkGeneratorDelegate extends ChunkGenerator {
     private final ConfigPack pack;
     private final CraftWorld world;
     
+    private volatile boolean structures = false;
+    
     
     public NMSChunkGeneratorDelegate(ChunkGenerator vanilla, ConfigPack pack, NMSBiomeProvider biomeProvider, CraftWorld world) {
         super(vanilla.b, vanilla.e, biomeProvider, biomeProvider, world.getSeed());
@@ -51,6 +52,14 @@ public class NMSChunkGeneratorDelegate extends ChunkGenerator {
         this.world = world;
     }
     
+    public void enableStructures() {
+        if(structures) {
+            throw new IllegalStateException("Structures have already been enabled!");
+        }
+        LOGGER.info("Enabling structure generation...");
+        this.structures = true;
+    }
+    
     @Override //applyCarvers
     public void a(RegionLimitedWorldAccess regionlimitedworldaccess, long var2, BiomeManager var4, StructureManager var5,
                   IChunkAccess ichunkaccess, WorldGenStage.Features var7) {
@@ -76,7 +85,9 @@ public class NMSChunkGeneratorDelegate extends ChunkGenerator {
     
     @Override
     public void a(GeneratorAccessSeed gas, StructureManager manager, IChunkAccess ica) {
-        vanilla.a(gas, manager, ica);
+        if(structures) {
+            vanilla.a(gas, manager, ica);
+        }
     }
     
     @Override

platforms/bukkit/src/main/java/com/dfsek/terra/bukkit/nms/NMSInjectListener.java

@@ -7,6 +7,7 @@ import org.bukkit.craftbukkit.v1_18_R2.CraftWorld;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.world.WorldInitEvent;
+import org.bukkit.event.world.WorldLoadEvent;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -46,4 +47,16 @@ public class NMSInjectListener implements Listener {
             INJECT_LOCK.unlock();
         }
     }
+    
+    @EventHandler
+    public void onWorldLoad(WorldLoadEvent event) {
+        if (INJECTED.contains(event.getWorld()) && event.getWorld().getGenerator() instanceof BukkitChunkGeneratorWrapper bukkitChunkGeneratorWrapper) {
+            LOGGER.info("Enabling structure deadlock workaround on world {}.", event.getWorld().getName());
+            CraftWorld craftWorld = (CraftWorld) event.getWorld();
+            WorldServer serverWorld = craftWorld.getHandle();
+            
+            ((NMSChunkGeneratorDelegate) serverWorld.k().a.u).enableStructures();
+            LOGGER.info("Thank you Bukkit.");
+        }
+    }
 }