RelicCraft/src/main/java/com/thebrokenrail/reliccraft/block/DragonEggHolderBlockEntity.java

package com.thebrokenrail.reliccraft.block;

import com.thebrokenrail.reliccraft.RelicCraft;
import net.minecraft.block.Block;
import net.minecraft.block.BlockState;
import net.minecraft.block.entity.BlockEntity;
import net.minecraft.entity.player.PlayerEntity;
import net.minecraft.inventory.Inventories;
import net.minecraft.inventory.Inventory;
import net.minecraft.item.ItemStack;
import net.minecraft.item.Items;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.util.Tickable;
import net.minecraft.util.collection.DefaultedList;
import java.util.Objects;

public class DragonEggHolderBlockEntity extends BlockEntity implements Inventory, Tickable {
    public DragonEggHolderBlockEntity() {
        super(RelicCraft.DRAGON_EGG_HOLDER_BLOCK_ENTITY);
    }

    @Override
    public void fromTag(BlockState state, CompoundTag tag) {
        super.fromTag(state, tag);
        DefaultedList<ItemStack> list = DefaultedList.ofSize(size(), ItemStack.EMPTY);
        Inventories.fromTag(tag, list);
        stack = list.get(0);
    }

    @Override
    public CompoundTag toTag(CompoundTag tag) {
        DefaultedList<ItemStack> list = DefaultedList.ofSize(size(), ItemStack.EMPTY);
        list.set(0, stack);
        Inventories.toTag(tag, list);
        return super.toTag(tag);
    }

    private ItemStack stack = ItemStack.EMPTY;

    @Override
    public int size() {
        return 1;
    }

    @Override
    public int getMaxCountPerStack() {
        return 1;
    }

    @Override
    public boolean isEmpty() {
        return stack.isEmpty();
    }

    @Override
    public ItemStack getStack(int slot) {
        return stack;
    }

    @Override
    public ItemStack removeStack(int slot, int amount) {
        ItemStack newStack = getStack(0).split(amount);
        markDirty();
        return newStack;
    }

    @Override
    public ItemStack removeStack(int slot) {
        ItemStack newStack = getStack(0).copy();
        setStack(0, ItemStack.EMPTY);
        return newStack;
    }

    @Override
    public void setStack(int slot, ItemStack stack) {
        this.stack = stack;
        if (stack.getCount() > getMaxCountPerStack()) {
            stack.setCount(getMaxCountPerStack());
        }
        markDirty();
    }

    @Override
    public boolean canPlayerUse(PlayerEntity player) {
        return true;
    }

    @Override
    public void clear() {
        setStack(0, ItemStack.EMPTY);
    }

    @Override
    public void tick() {
        if (hasWorld()) {
            assert getWorld() != null;
            Block block = getWorld().getBlockState(getPos()).getBlock();
            if (block instanceof AbstractDragonEggHolderBlock && !getWorld().isClient()) {
                ((AbstractDragonEggHolderBlock) block).tick(getWorld(), getPos());
            }
        }
    }

    @Override
    public boolean isValid(int slot, ItemStack stack) {
        return stack.getItem() == Items.DRAGON_EGG;
    }

    @Override
    public void markDirty() {
        super.markDirty();
        if (hasWorld() && !Objects.requireNonNull(getWorld()).isClient()) {
            updateBlockState();
        }
    }

    private void updateBlockState() {
        if (hasWorld()) {
            assert getWorld() != null;
            BlockState state = getWorld().getBlockState(pos);
            boolean active = !getStack(0).isEmpty();
            if (state.get(TeleportationRestrictorBlock.ACTIVE) != active) {
                getWorld().setBlockState(getPos(), state.with(TeleportationRestrictorBlock.ACTIVE, active));
                RelicCraft.playInteractTeleportRestrictorSound(getWorld(), getPos());
            }
        }
    }
}