Code/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.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.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> p_330436_, Level p_334777_) {
        super(p_330436_, p_334777_);
        this.noPhysics = true;
    }

    public static OminousItemSpawner create(Level p_328154_, ItemStack p_332415_) {
        OminousItemSpawner ominousitemspawner = new OminousItemSpawner(EntityType.OMINOUS_ITEM_SPAWNER, p_328154_);
        ominousitemspawner.spawnItemAfterTicks = p_328154_.random.nextIntBetweenInclusive(60, 120);
        ominousitemspawner.setItem(p_332415_);
        return ominousitemspawner;
    }

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

    private void tickServer(ServerLevel p_365525_) {
        if (this.tickCount == this.spawnItemAfterTicks - 36L) {
            p_365525_.playSound(null, this.blockPosition(), SoundEvents.TRIAL_SPAWNER_ABOUT_TO_SPAWN_ITEM, SoundSource.NEUTRAL);
        }

        if (this.tickCount >= this.spawnItemAfterTicks) {
            this.spawnItem();
            this.kill(p_365525_);
        }
    }

    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 p_363229_, ProjectileItem p_362437_, ItemStack p_369507_) {
        ProjectileItem.DispenseConfig projectileitem$dispenseconfig = p_362437_.createDispenseConfig();
        projectileitem$dispenseconfig.overrideDispenseEvent().ifPresent(p_374937_ -> p_363229_.levelEvent(p_374937_, this.blockPosition(), 0));
        Direction direction = Direction.DOWN;
        Projectile projectile = Projectile.spawnProjectileUsingShoot(
            p_362437_.asProjectile(p_363229_, this.position(), p_369507_, direction),
            p_363229_,
            p_369507_,
            direction.getStepX(),
            direction.getStepY(),
            direction.getStepZ(),
            projectileitem$dispenseconfig.power(),
            projectileitem$dispenseconfig.uncertainty()
        );
        projectile.setOwner(this);
        return projectile;
    }

    @Override
    protected void defineSynchedData(SynchedEntityData.Builder p_330200_) {
        p_330200_.define(DATA_ITEM, ItemStack.EMPTY);
    }

    @Override
    protected void readAdditionalSaveData(CompoundTag p_331393_) {
        RegistryOps<Tag> registryops = this.registryAccess().createSerializationContext(NbtOps.INSTANCE);
        this.setItem(p_331393_.read("item", ItemStack.CODEC, registryops).orElse(ItemStack.EMPTY));
        this.spawnItemAfterTicks = p_331393_.getLongOr("spawn_item_after_ticks", 0L);
    }

    @Override
    protected void addAdditionalSaveData(CompoundTag p_329696_) {
        if (!this.getItem().isEmpty()) {
            RegistryOps<Tag> registryops = this.registryAccess().createSerializationContext(NbtOps.INSTANCE);
            p_329696_.store("item", ItemStack.CODEC, registryops, this.getItem());
        }

        p_329696_.putLong("spawn_item_after_ticks", this.spawnItemAfterTicks);
    }

    @Override
    protected boolean canAddPassenger(Entity p_332041_) {
        return false;
    }

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

    @Override
    protected void addPassenger(Entity p_333815_) {
        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 d0 = 0.4;
            Vec3 vec31 = 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 vec32 = vec3.vectorTo(vec31);
            this.level().addParticle(ParticleTypes.OMINOUS_SPAWNING, vec3.x(), vec3.y(), vec3.z(), vec32.x(), vec32.y(), vec32.z());
        }
    }

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

    private void setItem(ItemStack p_328604_) {
        this.getEntityData().set(DATA_ITEM, p_328604_);
    }

    @Override
    public final boolean hurtServer(ServerLevel p_360846_, DamageSource p_368088_, float p_369389_) {
        return false;
    }
}