minecraft-src/net/minecraft/world/entity/OminousItemSpawner.java

package net.minecraft.world.entity;

import net.minecraft.core.Direction;
import net.minecraft.core.particles.ParticleTypes;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.nbt.NbtOps;
import net.minecraft.nbt.Tag;
import net.minecraft.network.syncher.EntityDataAccessor;
import net.minecraft.network.syncher.EntityDataSerializers;
import net.minecraft.network.syncher.SynchedEntityData;
import net.minecraft.network.syncher.SynchedEntityData.Builder;
import net.minecraft.resources.RegistryOps;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.sounds.SoundEvents;
import net.minecraft.sounds.SoundSource;
import net.minecraft.world.damagesource.DamageSource;
import net.minecraft.world.entity.item.ItemEntity;
import net.minecraft.world.entity.projectile.Projectile;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.ProjectileItem;
import net.minecraft.world.item.ProjectileItem.DispenseConfig;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.gameevent.GameEvent;
import net.minecraft.world.level.material.PushReaction;
import net.minecraft.world.phys.Vec3;

public class OminousItemSpawner extends Entity {
	private static final int SPAWN_ITEM_DELAY_MIN = 60;
	private static final int SPAWN_ITEM_DELAY_MAX = 120;
	private static final String TAG_SPAWN_ITEM_AFTER_TICKS = "spawn_item_after_ticks";
	private static final String TAG_ITEM = "item";
	private static final EntityDataAccessor<ItemStack> DATA_ITEM = SynchedEntityData.defineId(OminousItemSpawner.class, EntityDataSerializers.ITEM_STACK);
	public static final int TICKS_BEFORE_ABOUT_TO_SPAWN_SOUND = 36;
	private long spawnItemAfterTicks;

	public OminousItemSpawner(EntityType<? extends OminousItemSpawner> entityType, Level level) {
		super(entityType, level);
		this.noPhysics = true;
	}

	public static OminousItemSpawner create(Level level, ItemStack item) {
		OminousItemSpawner ominousItemSpawner = new OminousItemSpawner(EntityType.OMINOUS_ITEM_SPAWNER, level);
		ominousItemSpawner.spawnItemAfterTicks = level.random.nextIntBetweenInclusive(60, 120);
		ominousItemSpawner.setItem(item);
		return ominousItemSpawner;
	}

	@Override
	public void tick() {
		super.tick();
		if (this.level() instanceof ServerLevel serverLevel) {
			this.tickServer(serverLevel);
		} else {
			this.tickClient();
		}
	}

	private void tickServer(ServerLevel level) {
		if (this.tickCount == this.spawnItemAfterTicks - 36L) {
			level.playSound(null, this.blockPosition(), SoundEvents.TRIAL_SPAWNER_ABOUT_TO_SPAWN_ITEM, SoundSource.NEUTRAL);
		}

		if (this.tickCount >= this.spawnItemAfterTicks) {
			this.spawnItem();
			this.kill(level);
		}
	}

	private void tickClient() {
		if (this.level().getGameTime() % 5L == 0L) {
			this.addParticles();
		}
	}

	private void spawnItem() {
		if (this.level() instanceof ServerLevel serverLevel) {
			ItemStack itemStack = this.getItem();
			if (!itemStack.isEmpty()) {
				Entity entity;
				if (itemStack.getItem() instanceof ProjectileItem projectileItem) {
					entity = this.spawnProjectile(serverLevel, projectileItem, itemStack);
				} else {
					entity = new ItemEntity(serverLevel, this.getX(), this.getY(), this.getZ(), itemStack);
					serverLevel.addFreshEntity(entity);
				}

				serverLevel.levelEvent(3021, this.blockPosition(), 1);
				serverLevel.gameEvent(entity, GameEvent.ENTITY_PLACE, this.position());
				this.setItem(ItemStack.EMPTY);
			}
		}
	}

	private Entity spawnProjectile(ServerLevel level, ProjectileItem projectileItem, ItemStack stack) {
		DispenseConfig dispenseConfig = projectileItem.createDispenseConfig();
		dispenseConfig.overrideDispenseEvent().ifPresent(i -> level.levelEvent(i, this.blockPosition(), 0));
		Direction direction = Direction.DOWN;
		Projectile projectile = Projectile.spawnProjectileUsingShoot(
			projectileItem.asProjectile(level, this.position(), stack, direction),
			level,
			stack,
			direction.getStepX(),
			direction.getStepY(),
			direction.getStepZ(),
			dispenseConfig.power(),
			dispenseConfig.uncertainty()
		);
		projectile.setOwner(this);
		return projectile;
	}

	@Override
	protected void defineSynchedData(Builder builder) {
		builder.define(DATA_ITEM, ItemStack.EMPTY);
	}

	@Override
	protected void readAdditionalSaveData(CompoundTag tag) {
		RegistryOps<Tag> registryOps = this.registryAccess().createSerializationContext(NbtOps.INSTANCE);
		this.setItem((ItemStack)tag.read("item", ItemStack.CODEC, registryOps).orElse(ItemStack.EMPTY));
		this.spawnItemAfterTicks = tag.getLongOr("spawn_item_after_ticks", 0L);
	}

	@Override
	protected void addAdditionalSaveData(CompoundTag tag) {
		if (!this.getItem().isEmpty()) {
			RegistryOps<Tag> registryOps = this.registryAccess().createSerializationContext(NbtOps.INSTANCE);
			tag.store("item", ItemStack.CODEC, registryOps, this.getItem());
		}

		tag.putLong("spawn_item_after_ticks", this.spawnItemAfterTicks);
	}

	@Override
	protected boolean canAddPassenger(Entity passenger) {
		return false;
	}

	@Override
	protected boolean couldAcceptPassenger() {
		return false;
	}

	@Override
	protected void addPassenger(Entity passenger) {
		throw new IllegalStateException("Should never addPassenger without checking couldAcceptPassenger()");
	}

	@Override
	public PushReaction getPistonPushReaction() {
		return PushReaction.IGNORE;
	}

	@Override
	public boolean isIgnoringBlockTriggers() {
		return true;
	}

	public void addParticles() {
		Vec3 vec3 = this.position();
		int i = this.random.nextIntBetweenInclusive(1, 3);

		for (int j = 0; j < i; j++) {
			double d = 0.4;
			Vec3 vec32 = new Vec3(
				this.getX() + 0.4 * (this.random.nextGaussian() - this.random.nextGaussian()),
				this.getY() + 0.4 * (this.random.nextGaussian() - this.random.nextGaussian()),
				this.getZ() + 0.4 * (this.random.nextGaussian() - this.random.nextGaussian())
			);
			Vec3 vec33 = vec3.vectorTo(vec32);
			this.level().addParticle(ParticleTypes.OMINOUS_SPAWNING, vec3.x(), vec3.y(), vec3.z(), vec33.x(), vec33.y(), vec33.z());
		}
	}

	public ItemStack getItem() {
		return this.getEntityData().get(DATA_ITEM);
	}

	private void setItem(ItemStack item) {
		this.getEntityData().set(DATA_ITEM, item);
	}

	@Override
	public final boolean hurtServer(ServerLevel level, DamageSource damageSource, float amount) {
		return false;
	}
}