fix: correct reflected fields for chunk needs saving

- fixes #4064

Bukkit/src/main/java/com/plotsquared/bukkit/generator/BukkitPlotGenerator.java

@@ -34,6 +34,7 @@ import com.plotsquared.core.queue.ZeroedDelegateScopedQueueCoordinator;
 import com.plotsquared.core.util.ChunkManager;
 import com.sk89q.worldedit.bukkit.BukkitAdapter;
 import com.sk89q.worldedit.math.BlockVector2;
+import com.sk89q.worldedit.math.BlockVector3;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.bukkit.HeightMap;
@@ -420,7 +421,11 @@ public class BukkitPlotGenerator extends ChunkGenerator implements GeneratorWrap
         if (lastPlotArea != null && name.equals(this.levelName) && chunkX == lastChunkX && chunkZ == lastChunkZ) {
             return lastPlotArea;
         }
-        PlotArea area = UncheckedWorldLocation.at(name, chunkX << 4, 0, chunkZ << 4).getPlotArea();
+        BlockVector3 loc = BlockVector3.at(chunkX << 4, 0, chunkZ << 4);
+        if (lastPlotArea != null && lastPlotArea.getRegion().contains(loc) && lastPlotArea.getRegion().contains(loc)) {
+            return lastPlotArea;
+        }
+        PlotArea area = UncheckedWorldLocation.at(name, loc).getPlotArea();
         if (area == null) {
             throw new IllegalStateException(String.format(
                     "Cannot generate chunk that does not belong to a plot area. World: %s",

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/PlayerEventListener.java

@@ -1167,7 +1167,7 @@ public class PlayerEventListener implements Listener {
                     }
                 }
                 if (type.isEdible()) {
-                    //Allow all players to eat while also allowing the block place event ot be fired
+                    //Allow all players to eat while also allowing the block place event to be fired
                     return;
                 }
                 if (type == Material.ARMOR_STAND) {

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());
     }
 

Core/src/main/java/com/plotsquared/core/generator/HybridGen.java

@@ -69,8 +69,8 @@ public class HybridGen extends IndependentPlotGenerator {
             EnumSet<SchematicFeature> features
     ) {
         int minY; // Math.min(world.PLOT_HEIGHT, world.ROAD_HEIGHT);
-        if ((features.contains(SchematicFeature.ROAD) && Settings.Schematics.PASTE_ROAD_ON_TOP)
-                || (!features.contains(SchematicFeature.ROAD) && Settings.Schematics.PASTE_ON_TOP)) {
+        boolean isRoad = features.contains(SchematicFeature.ROAD);
+        if ((isRoad && Settings.Schematics.PASTE_ROAD_ON_TOP) || (!isRoad && Settings.Schematics.PASTE_ON_TOP)) {
             minY = world.SCHEM_Y;
         } else {
             minY = world.getMinBuildHeight();

Core/src/main/java/com/plotsquared/core/generator/HybridPlotManager.java

@@ -162,6 +162,7 @@ public class HybridPlotManager extends ClassicPlotManager {
         } else {
             minY = hybridPlotWorld.getMinBuildHeight();
         }
+        int schemYDiff = (isRoad ? hybridPlotWorld.getRoadYStart() : hybridPlotWorld.getPlotYStart()) - minY;
         BaseBlock airBlock = BlockTypes.AIR.getDefaultState().toBaseBlock();
         for (int x = pos1.getX(); x <= pos2.getX(); x++) {
             short absX = (short) ((x - hybridPlotWorld.ROAD_OFFSET_X) % size);
@@ -178,10 +179,14 @@ public class HybridPlotManager extends ClassicPlotManager {
                     for (int y = 0; y < blocks.length; y++) {
                         if (blocks[y] != null) {
                             queue.setBlock(x, minY + y, z, blocks[y]);
-                        } else if (!isRoad) {
-                            // This is necessary, otherwise any blocks not specified in the schematic will remain after a clear
-                            //  Do not set air for road as this may cause cavernous roads when debugroadregen is used
+                        } else if (y > schemYDiff) {
+                            // This is necessary, otherwise any blocks not specified in the schematic will remain after a clear.
+                            // This should only be done where the schematic has actually "started"
                             queue.setBlock(x, minY + y, z, airBlock);
+                        } else if (isRoad) {
+                            queue.setBlock(x, minY + y, z, hybridPlotWorld.ROAD_BLOCK.toPattern());
+                        } else {
+                            queue.setBlock(x, minY + y, z, hybridPlotWorld.MAIN_BLOCK.toPattern());
                         }
                     }
                 }

Core/src/main/java/com/plotsquared/core/generator/HybridPlotWorld.java

@@ -76,6 +76,9 @@ public class HybridPlotWorld extends ClassicPlotWorld {
      * The Y level at which schematic generation will start, lowest of either road or plot schematic generation.
      */
     public int SCHEM_Y;
+
+    private int plotY;
+    private int roadY;
     private Location SIGN_LOCATION;
     private File root = null;
     private int lastOverlayHeightError = Integer.MIN_VALUE;
@@ -252,13 +255,13 @@ public class HybridPlotWorld extends ClassicPlotWorld {
 
         SCHEM_Y = schematicStartHeight();
 
-        // plotY and roadY are important to allow plot and/or road schematic "overflow" into each other without causing AIOOB
-        //  exceptions when attempting either to set blocks to, or get block from G_SCH
+        // plotY and roadY are important to allow plot and/or road schematic "overflow" into each other
+        // without causing AIOOB exceptions when attempting either to set blocks to, or get block from G_SCH
         // Default plot schematic start height, normalized to the minimum height schematics are pasted from.
-        int plotY = PLOT_HEIGHT - SCHEM_Y;
+        plotY = PLOT_HEIGHT - SCHEM_Y;
         int minRoadWall = Settings.Schematics.USE_WALL_IN_ROAD_SCHEM_HEIGHT ? Math.min(ROAD_HEIGHT, WALL_HEIGHT) : ROAD_HEIGHT;
         // Default road schematic start height, normalized to the minimum height schematics are pasted from.
-        int roadY = minRoadWall - SCHEM_Y;
+        roadY = minRoadWall - SCHEM_Y;
 
         int worldGenHeight = getMaxGenHeight() - getMinGenHeight() + 1;
 
@@ -267,14 +270,15 @@ public class HybridPlotWorld extends ClassicPlotWorld {
 
         // SCHEM_Y should be normalised to the plot "start" height
         if (schematic3 != null) {
-            plotSchemHeight = maxSchematicHeight = schematic3.getClipboard().getDimensions().getY();
-            if (maxSchematicHeight == worldGenHeight) {
+            plotSchemHeight = schematic3.getClipboard().getDimensions().getY();
+            if (plotSchemHeight == worldGenHeight) {
                 SCHEM_Y = getMinGenHeight();
                 plotY = 0;
             } else if (!Settings.Schematics.PASTE_ON_TOP) {
                 SCHEM_Y = getMinBuildHeight();
                 plotY = 0;
             }
+            maxSchematicHeight = plotY + plotSchemHeight;
         }
 
         int roadSchemHeight;
@@ -554,4 +558,24 @@ public class HybridPlotWorld extends ClassicPlotWorld {
         return this.root;
     }
 
+    /**
+     * Get the y value where the plot schematic should be pasted from.
+     *
+     * @return plot schematic y start value
+     * @since TODO
+     */
+    public int getPlotYStart() {
+        return SCHEM_Y + plotY;
+    }
+
+    /**
+     * Get the y value where the road schematic should be pasted from.
+     *
+     * @return road schematic y start value
+     * @since TODO
+     */
+    public int getRoadYStart() {
+        return SCHEM_Y + roadY;
+    }
+
 }

Core/src/main/java/com/plotsquared/core/generator/HybridUtils.java

@@ -668,7 +668,7 @@ public class HybridUtils {
                     }
                     if (condition) {
                         BaseBlock[] blocks = plotWorld.G_SCH.get(MathMan.pair(absX, absZ));
-                        int minY = Settings.Schematics.PASTE_ROAD_ON_TOP ? plotWorld.SCHEM_Y : area.getMinGenHeight() + 1;
+                        int minY = plotWorld.getRoadYStart();
                         int maxDy = Math.max(extend, blocks.length);
                         for (int dy = 0; dy < maxDy; dy++) {
                             if (dy > blocks.length - 1) {

Core/src/main/java/com/plotsquared/core/plot/world/DefaultPlotAreaManager.java

@@ -29,17 +29,17 @@ import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 
 @Singleton
 public class DefaultPlotAreaManager implements PlotAreaManager {
 
     final PlotArea[] noPlotAreas = new PlotArea[0];
-    private final Map<String, PlotWorld> plotWorlds = new HashMap<>();
+    private final Map<String, PlotWorld> plotWorlds = new ConcurrentHashMap<>();
 
     @Override
     public @NonNull PlotArea[] getAllPlotAreas() {