Code/net/minecraft/world/level/levelgen/structure/structures/ShipwreckPieces.java

package net.minecraft.world.level.levelgen.structure.structures;

import java.util.Map;
import net.minecraft.Util;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Vec3i;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.resources.ResourceKey;
import net.minecraft.resources.ResourceLocation;
import net.minecraft.util.RandomSource;
import net.minecraft.world.RandomizableContainer;
import net.minecraft.world.level.ChunkPos;
import net.minecraft.world.level.ServerLevelAccessor;
import net.minecraft.world.level.StructureManager;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.block.Mirror;
import net.minecraft.world.level.block.Rotation;
import net.minecraft.world.level.chunk.ChunkGenerator;
import net.minecraft.world.level.levelgen.Heightmap;
import net.minecraft.world.level.levelgen.structure.BoundingBox;
import net.minecraft.world.level.levelgen.structure.StructurePieceAccessor;
import net.minecraft.world.level.levelgen.structure.TemplateStructurePiece;
import net.minecraft.world.level.levelgen.structure.pieces.StructurePieceSerializationContext;
import net.minecraft.world.level.levelgen.structure.pieces.StructurePieceType;
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.StructureTemplateManager;
import net.minecraft.world.level.storage.loot.BuiltInLootTables;
import net.minecraft.world.level.storage.loot.LootTable;

public class ShipwreckPieces {
    private static final int NUMBER_OF_BLOCKS_ALLOWED_IN_WORLD_GEN_REGION = 32;
    static final BlockPos PIVOT = new BlockPos(4, 0, 15);
    private static final ResourceLocation[] STRUCTURE_LOCATION_BEACHED = new ResourceLocation[]{
        ResourceLocation.withDefaultNamespace("shipwreck/with_mast"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_full"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_fronthalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_backhalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_full"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_fronthalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_backhalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/with_mast_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_full_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_fronthalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_backhalf_degraded")
    };
    private static final ResourceLocation[] STRUCTURE_LOCATION_OCEAN = new ResourceLocation[]{
        ResourceLocation.withDefaultNamespace("shipwreck/with_mast"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_full"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_fronthalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_backhalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_full"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_fronthalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_backhalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_full"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_fronthalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_backhalf"),
        ResourceLocation.withDefaultNamespace("shipwreck/with_mast_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_full_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_fronthalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/upsidedown_backhalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_full_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_fronthalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/sideways_backhalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_full_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_fronthalf_degraded"),
        ResourceLocation.withDefaultNamespace("shipwreck/rightsideup_backhalf_degraded")
    };
    static final Map<String, ResourceKey<LootTable>> MARKERS_TO_LOOT = Map.of(
        "map_chest", BuiltInLootTables.SHIPWRECK_MAP, "treasure_chest", BuiltInLootTables.SHIPWRECK_TREASURE, "supply_chest", BuiltInLootTables.SHIPWRECK_SUPPLY
    );

    public static ShipwreckPieces.ShipwreckPiece addRandomPiece(
        StructureTemplateManager p_334187_, BlockPos p_334016_, Rotation p_333925_, StructurePieceAccessor p_330683_, RandomSource p_331305_, boolean p_332987_
    ) {
        ResourceLocation resourcelocation = Util.getRandom(p_332987_ ? STRUCTURE_LOCATION_BEACHED : STRUCTURE_LOCATION_OCEAN, p_331305_);
        ShipwreckPieces.ShipwreckPiece shipwreckpieces$shipwreckpiece = new ShipwreckPieces.ShipwreckPiece(
            p_334187_, resourcelocation, p_334016_, p_333925_, p_332987_
        );
        p_330683_.addPiece(shipwreckpieces$shipwreckpiece);
        return shipwreckpieces$shipwreckpiece;
    }

    public static class ShipwreckPiece extends TemplateStructurePiece {
        private final boolean isBeached;

        public ShipwreckPiece(StructureTemplateManager p_229354_, ResourceLocation p_229355_, BlockPos p_229356_, Rotation p_229357_, boolean p_229358_) {
            super(StructurePieceType.SHIPWRECK_PIECE, 0, p_229354_, p_229355_, p_229355_.toString(), makeSettings(p_229357_), p_229356_);
            this.isBeached = p_229358_;
        }

        public ShipwreckPiece(StructureTemplateManager p_229360_, CompoundTag p_229361_) {
            super(StructurePieceType.SHIPWRECK_PIECE, p_229361_, p_229360_, p_391081_ -> makeSettings(p_229361_.read("Rot", Rotation.LEGACY_CODEC).orElseThrow()));
            this.isBeached = p_229361_.getBooleanOr("isBeached", false);
        }

        @Override
        protected void addAdditionalSaveData(StructurePieceSerializationContext p_229373_, CompoundTag p_229374_) {
            super.addAdditionalSaveData(p_229373_, p_229374_);
            p_229374_.putBoolean("isBeached", this.isBeached);
            p_229374_.store("Rot", Rotation.LEGACY_CODEC, this.placeSettings.getRotation());
        }

        private static StructurePlaceSettings makeSettings(Rotation p_229371_) {
            return new StructurePlaceSettings()
                .setRotation(p_229371_)
                .setMirror(Mirror.NONE)
                .setRotationPivot(ShipwreckPieces.PIVOT)
                .addProcessor(BlockIgnoreProcessor.STRUCTURE_AND_AIR);
        }

        @Override
        protected void handleDataMarker(String p_229376_, BlockPos p_229377_, ServerLevelAccessor p_229378_, RandomSource p_229379_, BoundingBox p_229380_) {
            ResourceKey<LootTable> resourcekey = ShipwreckPieces.MARKERS_TO_LOOT.get(p_229376_);
            if (resourcekey != null) {
                RandomizableContainer.setBlockEntityLootTable(p_229378_, p_229379_, p_229377_.below(), resourcekey);
            }
        }

        @Override
        public void postProcess(
            WorldGenLevel p_229363_,
            StructureManager p_229364_,
            ChunkGenerator p_229365_,
            RandomSource p_229366_,
            BoundingBox p_229367_,
            ChunkPos p_229368_,
            BlockPos p_229369_
        ) {
            if (this.isTooBigToFitInWorldGenRegion()) {
                super.postProcess(p_229363_, p_229364_, p_229365_, p_229366_, p_229367_, p_229368_, p_229369_);
            } else {
                int i = p_229363_.getMaxY() + 1;
                int j = 0;
                Vec3i vec3i = this.template.getSize();
                Heightmap.Types heightmap$types = this.isBeached ? Heightmap.Types.WORLD_SURFACE_WG : Heightmap.Types.OCEAN_FLOOR_WG;
                int k = vec3i.getX() * vec3i.getZ();
                if (k == 0) {
                    j = p_229363_.getHeight(heightmap$types, this.templatePosition.getX(), this.templatePosition.getZ());
                } else {
                    BlockPos blockpos = this.templatePosition.offset(vec3i.getX() - 1, 0, vec3i.getZ() - 1);

                    for (BlockPos blockpos1 : BlockPos.betweenClosed(this.templatePosition, blockpos)) {
                        int l = p_229363_.getHeight(heightmap$types, blockpos1.getX(), blockpos1.getZ());
                        j += l;
                        i = Math.min(i, l);
                    }

                    j /= k;
                }

                this.adjustPositionHeight(this.isBeached ? this.calculateBeachedPosition(i, p_229366_) : j);
                super.postProcess(p_229363_, p_229364_, p_229365_, p_229366_, p_229367_, p_229368_, p_229369_);
            }
        }

        public boolean isTooBigToFitInWorldGenRegion() {
            Vec3i vec3i = this.template.getSize();
            return vec3i.getX() > 32 || vec3i.getY() > 32;
        }

        public int calculateBeachedPosition(int p_332021_, RandomSource p_332823_) {
            return p_332021_ - this.template.getSize().getY() / 2 - p_332823_.nextInt(3);
        }

        public void adjustPositionHeight(int p_331508_) {
            this.templatePosition = new BlockPos(this.templatePosition.getX(), p_331508_, this.templatePosition.getZ());
        }
    }
}