fix: correct reflected fields for chunk needs saving

- fixes #4064

Bukkit/src/main/java/com/plotsquared/bukkit/listener/ChunkListener.java

@@ -26,6 +26,7 @@ import com.plotsquared.core.plot.Plot;
 import com.plotsquared.core.plot.PlotArea;
 import com.plotsquared.core.plot.world.PlotAreaManager;
 import com.plotsquared.core.plot.world.SinglePlotArea;
+import com.plotsquared.core.util.ReflectionUtils;
 import com.plotsquared.core.util.ReflectionUtils.RefClass;
 import com.plotsquared.core.util.ReflectionUtils.RefField;
 import com.plotsquared.core.util.ReflectionUtils.RefMethod;
@@ -64,9 +65,11 @@ public class ChunkListener implements Listener {
     private final PlotAreaManager plotAreaManager;
     private final int version;
 
+    private RefMethod methodSetUnsaved;
     private RefMethod methodGetHandleChunk;
     private RefMethod methodGetHandleWorld;
-    private RefField mustSave;
+    private RefField mustNotSave;
+    private Object objChunkStatusFull = null;
     /*
     private RefMethod methodGetFullChunk;
     private RefMethod methodGetBukkitChunk;
@@ -79,7 +82,6 @@ public class ChunkListener implements Listener {
     */
     private Chunk lastChunk;
     private boolean ignoreUnload = false;
-    private boolean isTrueForNotSave = true;
 
     @Inject
     public ChunkListener(final @NonNull PlotAreaManager plotAreaManager) {
@@ -90,22 +92,27 @@ public class ChunkListener implements Listener {
         }
         try {
             RefClass classCraftWorld = getRefClass("{cb}.CraftWorld");
-            this.methodGetHandleWorld = classCraftWorld.getMethod("getHandle");
             RefClass classCraftChunk = getRefClass("{cb}.CraftChunk");
-            this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle");
+            ReflectionUtils.RefClass classChunkAccess = getRefClass("net.minecraft.world.level.chunk.IChunkAccess");
+            this.methodSetUnsaved = classChunkAccess.getMethod("a", boolean.class);
+            try {
+                this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle");
+            } catch (NoSuchMethodException ignored) {
+                try {
+                    RefClass classChunkStatus = getRefClass("net.minecraft.world.level.chunk.ChunkStatus");
+                    this.objChunkStatusFull = classChunkStatus.getRealClass().getField("n").get(null);
+                    this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle", classChunkStatus.getRealClass());
+                } catch (NoSuchMethodException ex) {
+                    throw new RuntimeException(ex);
+                }
+            }
             try {
                 if (version < 17) {
                     RefClass classChunk = getRefClass("{nms}.Chunk");
-                    if (version == 13) {
-                        this.mustSave = classChunk.getField("mustSave");
-                        this.isTrueForNotSave = false;
-                    } else {
-                        this.mustSave = classChunk.getField("mustNotSave");
-                    }
+                    this.mustNotSave = classChunk.getField("mustNotSave");
                 } else {
                     RefClass classChunk = getRefClass("net.minecraft.world.level.chunk.Chunk");
-                    this.mustSave = classChunk.getField("mustNotSave");
-
+                    this.mustNotSave = classChunk.getField("mustNotSave");
                 }
             } catch (NoSuchFieldException e) {
                 e.printStackTrace();
@@ -167,10 +174,13 @@ public class ChunkListener implements Listener {
         if (safe && shouldSave(world, chunk.getX(), chunk.getZ())) {
             return false;
         }
-        Object c = this.methodGetHandleChunk.of(chunk).call();
-        RefField.RefExecutor field = this.mustSave.of(c);
-        if ((Boolean) field.get() != isTrueForNotSave) {
-            field.set(isTrueForNotSave);
+        Object c = objChunkStatusFull != null
+                ? this.methodGetHandleChunk.of(chunk).call(objChunkStatusFull)
+                : this.methodGetHandleChunk.of(chunk).call();
+        RefField.RefExecutor field = this.mustNotSave.of(c);
+        methodSetUnsaved.of(c).call(false);
+        if (!((Boolean) field.get())) {
+            field.set(true);
             if (chunk.isLoaded()) {
                 ignoreUnload = true;
                 chunk.unload(false);

Bukkit/src/main/java/com/plotsquared/bukkit/listener/SingleWorldListener.java

@@ -31,45 +31,39 @@ import org.bukkit.event.Listener;
 import org.bukkit.event.world.ChunkEvent;
 import org.bukkit.event.world.ChunkLoadEvent;
 
-import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 
 import static com.plotsquared.core.util.ReflectionUtils.getRefClass;
 
 public class SingleWorldListener implements Listener {
 
-    private final Method methodGetHandleChunk;
-    private Field shouldSave = null;
+    private final Method methodSetUnsaved;
+    private Method methodGetHandleChunk;
+    private Object objChunkStatusFull = null;
 
     public SingleWorldListener() throws Exception {
         ReflectionUtils.RefClass classCraftChunk = getRefClass("{cb}.CraftChunk");
-        this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle").getRealMethod();
+        ReflectionUtils.RefClass classChunkAccess = getRefClass("net.minecraft.world.level.chunk.IChunkAccess");
+        this.methodSetUnsaved = classChunkAccess.getMethod("a", boolean.class).getRealMethod();
         try {
-            if (PlotSquared.platform().serverVersion()[1] < 17) {
-                ReflectionUtils.RefClass classChunk = getRefClass("{nms}.Chunk");
-                if (PlotSquared.platform().serverVersion()[1] == 13) {
-                    this.shouldSave = classChunk.getField("mustSave").getRealField();
-                } else {
-                    this.shouldSave = classChunk.getField("s").getRealField();
-                }
-            } else if (PlotSquared.platform().serverVersion()[1] == 17) {
-                ReflectionUtils.RefClass classChunk = getRefClass("net.minecraft.world.level.chunk.Chunk");
-                this.shouldSave = classChunk.getField("r").getRealField();
-            } else if (PlotSquared.platform().serverVersion()[1] == 18) {
-                ReflectionUtils.RefClass classChunk = getRefClass("net.minecraft.world.level.chunk.IChunkAccess");
-                this.shouldSave = classChunk.getField("b").getRealField();
+            this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle").getRealMethod();
+        } catch (NoSuchMethodException ignored) {
+            try {
+                ReflectionUtils.RefClass classChunkStatus = getRefClass("net.minecraft.world.level.chunk.ChunkStatus");
+                this.objChunkStatusFull = classChunkStatus.getRealClass().getField("n").get(null);
+                this.methodGetHandleChunk = classCraftChunk.getMethod("getHandle", classChunkStatus.getRealClass()).getRealMethod();
+            } catch (NoSuchMethodException ex) {
+                throw new RuntimeException(ex);
             }
-        } catch (NoSuchFieldException e) {
-            e.printStackTrace();
         }
     }
 
     public void markChunkAsClean(Chunk chunk) {
         try {
-            Object nmsChunk = methodGetHandleChunk.invoke(chunk);
-            if (shouldSave != null) {
-                this.shouldSave.set(nmsChunk, false);
-            }
+            Object nmsChunk = objChunkStatusFull != null
+                    ? this.methodGetHandleChunk.invoke(chunk, objChunkStatusFull)
+                    : this.methodGetHandleChunk.invoke(chunk);
+            methodSetUnsaved.invoke(nmsChunk, false);
         } catch (Throwable e) {
             e.printStackTrace();
         }
@@ -85,7 +79,12 @@ public class SingleWorldListener implements Listener {
         if (!SinglePlotArea.isSinglePlotWorld(name)) {
             return;
         }
-
+        int x = event.getChunk().getX();
+        int z = event.getChunk().getZ();
+        if (x < 16 && x > -16 && z < 16 && z > -16) {
+            // Allow spawn to generate
+            return;
+        }
         markChunkAsClean(event.getChunk());
     }