BetterEnd/src/main/java/ru/betterend/world/features/CrashedShipFeature.java

package ru.betterend.world.features;

import net.minecraft.core.BlockPos;
import net.minecraft.resources.ResourceLocation;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.Mirror;
import net.minecraft.world.level.block.Rotation;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.levelgen.feature.FeaturePlaceContext;
import net.minecraft.world.level.levelgen.feature.configurations.NoneFeatureConfiguration;
import net.minecraft.world.level.levelgen.structure.BoundingBox;
import net.minecraft.world.level.levelgen.structure.templatesystem.BlockIgnoreProcessor;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructurePlaceSettings;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructureProcessor;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructureProcessorType;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructureTemplate;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructureTemplate.StructureBlockInfo;
import net.minecraft.world.level.material.Material;
import ru.bclib.api.TagAPI;
import ru.bclib.util.MHelper;
import ru.bclib.util.StructureHelper;
import ru.bclib.world.features.NBTStructureFeature;
import ru.betterend.util.BlockFixer;

import java.util.Random;

public class CrashedShipFeature extends NBTStructureFeature {
	private static final StructureProcessor REPLACER;
	private static final String STRUCTURE_PATH = "/data/minecraft/structures/end_city/ship.nbt";
	private StructureTemplate structure;
	
	@Override
	protected StructureTemplate getStructure(WorldGenLevel world, BlockPos pos, Random random) {
		if (structure == null) {
			structure = world.getLevel().getStructureManager().getOrCreate(new ResourceLocation("end_city/ship"));
			if (structure == null) {
				structure = StructureHelper.readStructure(STRUCTURE_PATH);
			}
		}
		return structure;
	}
	
	@Override
	protected boolean canSpawn(WorldGenLevel world, BlockPos pos, Random random) {
		long x = pos.getX() >> 4;
		long z = pos.getX() >> 4;
		if (x * x + z * z < 3600) {
			return false;
		}
		return pos.getY() > 5 && world.getBlockState(pos.below()).is(TagAPI.BLOCK_GEN_TERRAIN);
	}
	
	@Override
	protected Rotation getRotation(WorldGenLevel world, BlockPos pos, Random random) {
		return Rotation.getRandom(random);
	}
	
	@Override
	protected Mirror getMirror(WorldGenLevel world, BlockPos pos, Random random) {
		return Mirror.values()[random.nextInt(3)];
	}
	
	@Override
	protected int getYOffset(StructureTemplate structure, WorldGenLevel world, BlockPos pos, Random random) {
		int min = structure.getSize().getY() >> 3;
		int max = structure.getSize().getY() >> 2;
		return -MHelper.randRange(min, max, random);
	}
	
	@Override
	protected TerrainMerge getTerrainMerge(WorldGenLevel world, BlockPos pos, Random random) {
		return TerrainMerge.NONE;
	}
	
	@Override
	public boolean place(FeaturePlaceContext<NoneFeatureConfiguration> featureConfig) {
		final Random random = featureConfig.random();
		BlockPos center = featureConfig.origin();
		final WorldGenLevel world = featureConfig.level();
		center = new BlockPos(((center.getX() >> 4) << 4) | 8, 128, ((center.getZ() >> 4) << 4) | 8);
		center = getGround(world, center);
		BoundingBox bounds = makeBox(center);
		
		if (!canSpawn(world, center, random)) {
			return false;
		}
		
		StructureTemplate structure = getStructure(world, center, random);
		Rotation rotation = getRotation(world, center, random);
		Mirror mirror = getMirror(world, center, random);
		BlockPos offset = StructureTemplate.transform(
			new BlockPos(structure.getSize()),
			mirror,
			rotation,
			BlockPos.ZERO
		);
		center = center.offset(0, getYOffset(structure, world, center, random) + 0.5, 0);
		StructurePlaceSettings placementData = new StructurePlaceSettings().setRotation(rotation).setMirror(mirror);
		center = center.offset(-offset.getX() * 0.5, 0, -offset.getZ() * 0.5);
		
		BoundingBox structB = structure.getBoundingBox(placementData, center);
		bounds = StructureHelper.intersectBoxes(bounds, structB);
		
		addStructureData(placementData);
		structure.placeInWorld(world, center, center, placementData.setBoundingBox(bounds), random, 2);
		
		StructureHelper.erodeIntense(world, bounds, random);
		BlockFixer.fixBlocks(
			world,
			new BlockPos(bounds.minX(), bounds.minY(), bounds.minZ()),
			new BlockPos(bounds.maxX(), bounds.maxY(), bounds.maxZ())
		);
		
		return true;
	}
	
	@Override
	protected void addStructureData(StructurePlaceSettings data) {
		data.addProcessor(BlockIgnoreProcessor.STRUCTURE_AND_AIR).addProcessor(REPLACER).setIgnoreEntities(true);
	}
	
	static {
		REPLACER = new StructureProcessor() {
			@Override
			public StructureBlockInfo processBlock(LevelReader worldView, BlockPos pos, BlockPos blockPos, StructureBlockInfo structureBlockInfo, StructureBlockInfo structureBlockInfo2, StructurePlaceSettings structurePlacementData) {
				BlockState state = structureBlockInfo2.state;
				if (state.is(Blocks.SPAWNER) || state.getMaterial().equals(Material.WOOL)) {
					return new StructureBlockInfo(structureBlockInfo2.pos, AIR, null);
				}
				return structureBlockInfo2;
			}
			
			@Override
			protected StructureProcessorType<?> getType() {
				return StructureProcessorType.NOP;
			}
		};
	}
}