minecraft-src/net/minecraft/world/item/component/BundleContents.java

package net.minecraft.world.item.component;

import com.google.common.collect.Lists;
import com.mojang.serialization.Codec;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Stream;
import net.minecraft.core.component.DataComponents;
import net.minecraft.network.RegistryFriendlyByteBuf;
import net.minecraft.network.codec.ByteBufCodecs;
import net.minecraft.network.codec.StreamCodec;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.inventory.Slot;
import net.minecraft.world.inventory.tooltip.TooltipComponent;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.block.entity.BeehiveBlockEntity;
import org.apache.commons.lang3.math.Fraction;
import org.jetbrains.annotations.Nullable;

public final class BundleContents implements TooltipComponent {
	public static final BundleContents EMPTY = new BundleContents(List.of());
	public static final Codec<BundleContents> CODEC = ItemStack.CODEC.listOf().xmap(BundleContents::new, bundleContents -> bundleContents.items);
	public static final StreamCodec<RegistryFriendlyByteBuf, BundleContents> STREAM_CODEC = ItemStack.STREAM_CODEC
		.apply(ByteBufCodecs.list())
		.map(BundleContents::new, bundleContents -> bundleContents.items);
	private static final Fraction BUNDLE_IN_BUNDLE_WEIGHT = Fraction.getFraction(1, 16);
	private static final int NO_STACK_INDEX = -1;
	final List<ItemStack> items;
	final Fraction weight;

	BundleContents(List<ItemStack> items, Fraction weight) {
		this.items = items;
		this.weight = weight;
	}

	public BundleContents(List<ItemStack> items) {
		this(items, computeContentWeight(items));
	}

	private static Fraction computeContentWeight(List<ItemStack> content) {
		Fraction fraction = Fraction.ZERO;

		for (ItemStack itemStack : content) {
			fraction = fraction.add(getWeight(itemStack).multiplyBy(Fraction.getFraction(itemStack.getCount(), 1)));
		}

		return fraction;
	}

	static Fraction getWeight(ItemStack stack) {
		BundleContents bundleContents = stack.get(DataComponents.BUNDLE_CONTENTS);
		if (bundleContents != null) {
			return BUNDLE_IN_BUNDLE_WEIGHT.add(bundleContents.weight());
		} else {
			List<BeehiveBlockEntity.Occupant> list = stack.getOrDefault(DataComponents.BEES, List.of());
			return !list.isEmpty() ? Fraction.ONE : Fraction.getFraction(1, stack.getMaxStackSize());
		}
	}

	public ItemStack getItemUnsafe(int index) {
		return (ItemStack)this.items.get(index);
	}

	public Stream<ItemStack> itemCopyStream() {
		return this.items.stream().map(ItemStack::copy);
	}

	public Iterable<ItemStack> items() {
		return this.items;
	}

	public Iterable<ItemStack> itemsCopy() {
		return Lists.<ItemStack, ItemStack>transform(this.items, ItemStack::copy);
	}

	public int size() {
		return this.items.size();
	}

	public Fraction weight() {
		return this.weight;
	}

	public boolean isEmpty() {
		return this.items.isEmpty();
	}

	public boolean equals(Object object) {
		if (this == object) {
			return true;
		} else {
			return !(object instanceof BundleContents bundleContents)
				? false
				: this.weight.equals(bundleContents.weight) && ItemStack.listMatches(this.items, bundleContents.items);
		}
	}

	public int hashCode() {
		return ItemStack.hashStackList(this.items);
	}

	public String toString() {
		return "BundleContents" + this.items;
	}

	public static class Mutable {
		private final List<ItemStack> items;
		private Fraction weight;

		public Mutable(BundleContents contents) {
			this.items = new ArrayList(contents.items);
			this.weight = contents.weight;
		}

		public BundleContents.Mutable clearItems() {
			this.items.clear();
			this.weight = Fraction.ZERO;
			return this;
		}

		private int findStackIndex(ItemStack stack) {
			if (!stack.isStackable()) {
				return -1;
			} else {
				for (int i = 0; i < this.items.size(); i++) {
					if (ItemStack.isSameItemSameComponents((ItemStack)this.items.get(i), stack)) {
						return i;
					}
				}

				return -1;
			}
		}

		private int getMaxAmountToAdd(ItemStack stack) {
			Fraction fraction = Fraction.ONE.subtract(this.weight);
			return Math.max(fraction.divideBy(BundleContents.getWeight(stack)).intValue(), 0);
		}

		public int tryInsert(ItemStack stack) {
			if (!stack.isEmpty() && stack.getItem().canFitInsideContainerItems()) {
				int i = Math.min(stack.getCount(), this.getMaxAmountToAdd(stack));
				if (i == 0) {
					return 0;
				} else {
					this.weight = this.weight.add(BundleContents.getWeight(stack).multiplyBy(Fraction.getFraction(i, 1)));
					int j = this.findStackIndex(stack);
					if (j != -1) {
						ItemStack itemStack = (ItemStack)this.items.remove(j);
						ItemStack itemStack2 = itemStack.copyWithCount(itemStack.getCount() + i);
						stack.shrink(i);
						this.items.add(0, itemStack2);
					} else {
						this.items.add(0, stack.split(i));
					}

					return i;
				}
			} else {
				return 0;
			}
		}

		public int tryTransfer(Slot slot, Player player) {
			ItemStack itemStack = slot.getItem();
			int i = this.getMaxAmountToAdd(itemStack);
			return this.tryInsert(slot.safeTake(itemStack.getCount(), i, player));
		}

		@Nullable
		public ItemStack removeOne() {
			if (this.items.isEmpty()) {
				return null;
			} else {
				ItemStack itemStack = ((ItemStack)this.items.remove(0)).copy();
				this.weight = this.weight.subtract(BundleContents.getWeight(itemStack).multiplyBy(Fraction.getFraction(itemStack.getCount(), 1)));
				return itemStack;
			}
		}

		public Fraction weight() {
			return this.weight;
		}

		public BundleContents toImmutable() {
			return new BundleContents(List.copyOf(this.items), this.weight);
		}
	}
}