buffered world builder api

common/api/src/main/java/com/dfsek/terra/api/world/BufferedWorld.java

@@ -1,12 +1,18 @@
 package com.dfsek.terra.api.world;
 
+import java.util.Objects;
+
 import com.dfsek.terra.api.block.entity.BlockEntity;
 import com.dfsek.terra.api.block.state.BlockState;
 import com.dfsek.terra.api.config.ConfigPack;
 import com.dfsek.terra.api.entity.Entity;
 import com.dfsek.terra.api.entity.EntityType;
+import com.dfsek.terra.api.util.vector.Vector3Int;
 import com.dfsek.terra.api.world.biome.generation.BiomeProvider;
 import com.dfsek.terra.api.world.chunk.generation.ChunkGenerator;
+import com.dfsek.terra.api.world.util.Interceptors;
+import com.dfsek.terra.api.world.util.ReadInterceptor;
+import com.dfsek.terra.api.world.util.WriteInterceptor;
 
 
 /**
@@ -17,12 +23,18 @@ public class BufferedWorld implements WritableWorld {
     private final WritableWorld delegate;
     private final int offsetX, offsetY, offsetZ;
     
-    protected BufferedWorld(WritableWorld delegate, int offsetX, int offsetY, int offsetZ) {
+    private final ReadInterceptor readInterceptor;
+    private final WriteInterceptor writeInterceptor;
+    
+    protected BufferedWorld(WritableWorld delegate, int offsetX, int offsetY, int offsetZ,
+                            ReadInterceptor readInterceptor, WriteInterceptor writeInterceptor) {
         this.delegate = delegate;
         this.offsetX = offsetX;
         
         this.offsetY = offsetY;
         this.offsetZ = offsetZ;
+        this.readInterceptor = readInterceptor;
+        this.writeInterceptor = writeInterceptor;
     }
     
     @Override
@@ -32,7 +44,7 @@ public class BufferedWorld implements WritableWorld {
     
     @Override
     public BlockState getBlockState(int x, int y, int z) {
-        return delegate.getBlockState(x + offsetX, y + offsetY, z + offsetZ);
+        return readInterceptor.read(x, y, z, delegate);
     }
     
     @Override
@@ -72,7 +84,7 @@ public class BufferedWorld implements WritableWorld {
     
     @Override
     public void setBlockState(int x, int y, int z, BlockState data, boolean physics) {
-        delegate.setBlockState(x + offsetX, y + offsetY, z + offsetZ, data, physics);
+        writeInterceptor.write(x, y, z, data, delegate, physics);
     }
     
     @Override
@@ -82,9 +94,69 @@ public class BufferedWorld implements WritableWorld {
     
     /**
      * Get the world this {@link BufferedWorld} delegates to.
+     *
      * @return Delegate world.
      */
     public WritableWorld getDelegate() {
         return delegate;
     }
+    
+    public static final class Builder {
+        private final WritableWorld delegate;
+        private ReadInterceptor readInterceptor;
+        private WriteInterceptor writeInterceptor;
+        
+        private int x = 0;
+        private int y = 0;
+        private int z = 0;
+        
+        private Builder(WritableWorld delegate) {
+            this.delegate = delegate;
+        }
+        
+        public Builder read(ReadInterceptor interceptor) {
+            this.readInterceptor = interceptor;
+            return this;
+        }
+        
+        public Builder write(WriteInterceptor interceptor) {
+            this.writeInterceptor = interceptor;
+            return this;
+        }
+        
+        public Builder offsetX(int x) {
+            this.x = x;
+            return this;
+        }
+        
+        public Builder offsetY(int y) {
+            this.y = y;
+            return this;
+        }
+        
+        public Builder offsetZ(int z) {
+            this.z = z;
+            return this;
+        }
+        
+        public Builder offset(Vector3Int vector) {
+            this.x = vector.getX();
+            this.y = vector.getY();
+            this.z = vector.getZ();
+            return this;
+        }
+        
+        public BufferedWorld build() {
+            return new BufferedWorld(delegate,
+                                     x,
+                                     y,
+                                     z,
+                                     Objects.requireNonNullElse(readInterceptor, Interceptors.readThrough()),
+                                     Objects.requireNonNullElse(writeInterceptor, Interceptors.writeThrough()));
+        }
+    }
+    
+    protected static Builder builder(WritableWorld world) {
+        return new Builder(world);
+    }
 }

common/api/src/main/java/com/dfsek/terra/api/world/WritableWorld.java

@@ -6,6 +6,7 @@ import com.dfsek.terra.api.entity.EntityType;
 import com.dfsek.terra.api.util.vector.Vector3;
 import com.dfsek.terra.api.util.vector.Vector3Int;
 import com.dfsek.terra.api.world.chunk.generation.util.Column;
+import com.dfsek.terra.api.world.util.Interceptors;
 
 
 public interface WritableWorld extends ReadableWorld {
@@ -55,7 +56,11 @@ public interface WritableWorld extends ReadableWorld {
     Entity spawnEntity(double x, double y, double z, EntityType entityType);
     
     default BufferedWorld buffer(int offsetX, int offsetY, int offsetZ) {
-        return new BufferedWorld(this, offsetX, offsetY, offsetZ);
+        return BufferedWorld.builder(this).offsetX(offsetX).offsetY(offsetY).offsetZ(offsetZ).build();
+    }
+    
+    default BufferedWorld.Builder buffer() {
+        return BufferedWorld.builder(this);
     }
     
     default Column<WritableWorld> column(int x, int z) {

common/api/src/main/java/com/dfsek/terra/api/world/util/Interceptors.java

@@ -0,0 +1,17 @@
+package com.dfsek.terra.api.world.util;
+
+public final class Interceptors {
+    private static final ReadInterceptor READ_THROUGH = ((x, y, z, world) -> world.getBlockState(x, y, z));
+    private static final WriteInterceptor WRITE_THROUGH = ((x, y, z, block, world, physics) -> world.setBlockState(x, y, z, block, physics));
+    private Interceptors() {
+    
+    }
+    
+    public static ReadInterceptor readThrough() {
+        return READ_THROUGH;
+    }
+    
+    public static WriteInterceptor writeThrough() {
+        return WRITE_THROUGH;
+    }
+}

common/api/src/main/java/com/dfsek/terra/api/world/util/ReadInterceptor.java

@@ -0,0 +1,9 @@
+package com.dfsek.terra.api.world.util;
+
+import com.dfsek.terra.api.block.state.BlockState;
+import com.dfsek.terra.api.world.ReadableWorld;
+
+
+public interface ReadInterceptor {
+    BlockState read(int x, int y, int z, ReadableWorld world);
+}

common/api/src/main/java/com/dfsek/terra/api/world/util/WriteInterceptor.java

@@ -0,0 +1,13 @@
+package com.dfsek.terra.api.world.util;
+
+import com.dfsek.terra.api.block.state.BlockState;
+import com.dfsek.terra.api.world.WritableWorld;
+
+
+public interface WriteInterceptor {
+    default void write(int x, int y, int z, BlockState block, WritableWorld world) {
+        write(x, y, z, block, world, false);
+    }
+    
+    void write(int x, int y, int z, BlockState block, WritableWorld world, boolean physics);
+}