From 12c4df777dea48fd4fd5d9bb147b88aa85a0c199 Mon Sep 17 00:00:00 2001
From: Mike Primm <mike@primmhome.com>
Date: Sat, 1 Dec 2018 19:22:47 -0600
Subject: [PATCH] Add workaround for Spigot 1.13.2 bug with
 loadChunk(x,z,false)

Workaround problem with fact that World.loadChunk(x, z, false) fails
when called on existing chunks that have not been migrated to 1.13.x
format.
---
 .../helper/v113_2/MapChunkCache113_2.java     | 22 +++++++++++++++++++
 .../bukkit/helper/AbstractMapChunkCache.java  |  6 ++++-
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/bukkit-helper-113-2/src/main/java/org/dynmap/bukkit/helper/v113_2/MapChunkCache113_2.java b/bukkit-helper-113-2/src/main/java/org/dynmap/bukkit/helper/v113_2/MapChunkCache113_2.java
index 382d82ea..6d822667 100644
--- a/bukkit-helper-113-2/src/main/java/org/dynmap/bukkit/helper/v113_2/MapChunkCache113_2.java
+++ b/bukkit-helper-113-2/src/main/java/org/dynmap/bukkit/helper/v113_2/MapChunkCache113_2.java
@@ -2,6 +2,7 @@ package org.dynmap.bukkit.helper.v113_2;
 
 import org.bukkit.block.Biome;
 import org.bukkit.ChunkSnapshot;
+import org.bukkit.World;
 import org.dynmap.bukkit.helper.AbstractMapChunkCache;
 import org.dynmap.bukkit.helper.BukkitVersionHelper;
 import org.dynmap.renderer.DynmapBlockState;
@@ -63,4 +64,25 @@ public class MapChunkCache113_2 extends AbstractMapChunkCache {
 	public Snapshot wrapChunkSnapshot(ChunkSnapshot css) {
 		return new WrappedSnapshot(css);
 	}
+	@Override
+    public boolean loadChunkNoGenerate(World w, int x, int z) {
+		boolean rslt = w.loadChunk(x,  z, false);
+		// Workaround for Spigot 1.13.2 bug - check if generated and do load-with-generate if so to drive migration of old chunks
+		if (!rslt) {
+			boolean generated = true;
+			// Check one in each direction: see if all are generated
+			for (int xx = x-3; xx <= x+3; xx++) {
+				for (int zz = z-3; zz <= z+3; zz++) {
+					if (w.isChunkGenerated(xx, zz) == false) {
+						generated = false;
+						break;
+					}
+				}
+			}
+			if (generated) {
+				rslt = w.loadChunk(x, z, true);
+			}
+		}
+		return rslt;
+    }
 }
diff --git a/bukkit-helper/src/main/java/org/dynmap/bukkit/helper/AbstractMapChunkCache.java b/bukkit-helper/src/main/java/org/dynmap/bukkit/helper/AbstractMapChunkCache.java
index d106ac6a..5eec9145 100644
--- a/bukkit-helper/src/main/java/org/dynmap/bukkit/helper/AbstractMapChunkCache.java
+++ b/bukkit-helper/src/main/java/org/dynmap/bukkit/helper/AbstractMapChunkCache.java
@@ -796,7 +796,7 @@ public abstract class AbstractMapChunkCache extends MapChunkCache {
                 wasLoaded = true;
             }
             try {
-                didload = w.loadChunk(chunk.x, chunk.z, false);
+                didload = loadChunkNoGenerate(w, chunk.x, chunk.z);
             } catch (Throwable t) { /* Catch chunk error from Bukkit */
                 Log.warning("Bukkit error loading chunk " + chunk.x + "," + chunk.z + " on " + w.getName());
                 if(!wasLoaded) {    /* If wasn't loaded, we loaded it if it now is */
@@ -1013,6 +1013,10 @@ public abstract class AbstractMapChunkCache extends MapChunkCache {
         return dw;
     }
     
+    public boolean loadChunkNoGenerate(World w, int x, int z) {
+        return w.loadChunk(x, z, false);
+    }
+    
     static {
         Biome[] b = Biome.values();
         BiomeMap[] bm = BiomeMap.values();