From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Sun, 25 Dec 2022 23:39:05 +0100
Subject: [PATCH] Ignore null legacy structure data

License: GPL-3.0 (https://www.gnu.org/licenses/gpl-3.0.html)
Gale - https://galemc.org

This patch is based on the following patch:
"Add null check in LegacyStructureDataHandler"
By: PureGero <puregero@gmail.com>
As part of: MultiPaper (https://github.com/MultiPaper/MultiPaper)
Licensed under: GPL-3.0 (https://www.gnu.org/licenses/gpl-3.0.html)

diff --git a/src/main/java/net/minecraft/world/level/levelgen/structure/LegacyStructureDataHandler.java b/src/main/java/net/minecraft/world/level/levelgen/structure/LegacyStructureDataHandler.java
index cc7222cc7e53e8ae693e4e94ad53391db7a663c4..9d1d7033fdd2ae65b8fd323e9199b9d5ea43fe35 100644
--- a/src/main/java/net/minecraft/world/level/levelgen/structure/LegacyStructureDataHandler.java
+++ b/src/main/java/net/minecraft/world/level/levelgen/structure/LegacyStructureDataHandler.java
@@ -19,6 +19,7 @@ import net.minecraft.resources.ResourceKey;
 import net.minecraft.world.level.ChunkPos;
 import net.minecraft.world.level.dimension.LevelStem;
 import net.minecraft.world.level.storage.DimensionDataStorage;
+import org.galemc.gale.configuration.GaleGlobalConfiguration;
 
 public class LegacyStructureDataHandler {
 
@@ -171,6 +172,7 @@ public class LegacyStructureDataHandler {
 
     private void populateCaches(@Nullable DimensionDataStorage persistentStateManager) {
         if (persistentStateManager != null) {
+            boolean ignoreNullLegacyStructureData = GaleGlobalConfiguration.get().misc.ignoreNullLegacyStructureData; // Gale - MultiPaper - ignore null legacy structure data
             Iterator iterator = this.legacyKeys.iterator();
 
             while (iterator.hasNext()) {
@@ -178,7 +180,11 @@ public class LegacyStructureDataHandler {
                 CompoundTag nbttagcompound = new CompoundTag();
 
                 try {
-                    nbttagcompound = persistentStateManager.readTagFromDisk(s, 1493).getCompound("data").getCompound("Features");
+                    // Gale start - MultiPaper - ignore null legacy structure data
+                    CompoundTag tag = persistentStateManager.readTagFromDisk(s, 1493);
+                    if (ignoreNullLegacyStructureData && tag == null) continue;
+                    nbttagcompound = tag.getCompound("data").getCompound("Features");
+                    // Gale end - MultiPaper - ignore null legacy structure data
                     if (nbttagcompound.isEmpty()) {
                         continue;
                     }
diff --git a/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java b/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
index 1b7ff78c12bc9eb04bc0f74b21ccdbbec6dc54c4..2209468501f1b1bcf01c1944c696aeee27af2ba1 100644
--- a/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
+++ b/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
@@ -88,6 +88,19 @@ public class GaleGlobalConfiguration extends ConfigurationPart {
         public int premiumAccountSlowLoginTimeout = -1;
         // Gale end - make slow login timeout configurable
 
+        // Gale start - MultiPaper - ignore null legacy structure data
+        /**
+         * Whether to ignore any legacy structure data, for which the NBT tag parser returns null for some reason.
+         * If true, no warning will be given when this happens.
+         * If false, an exception will be thrown in the console when this happens.
+         * <ul>
+         *     <li><i>Default</i>: false</li>
+         *     <li><i>Vanilla</i>: false</li>
+         * </ul>
+         */
+        public boolean ignoreNullLegacyStructureData = false;
+        // Gale end - MultiPaper - ignore null legacy structure data
+
         public IncludeInTimingsReport includeInTimingsReport;
 
         public class IncludeInTimingsReport extends ConfigurationPart {