MinestomGameJam/src/main/java/dev/celestialfox/spectrumsurvival/utils/classes/NPC.java

package dev.celestialfox.spectrumsurvival.utils.classes;

import net.kyori.adventure.text.Component;
import net.minestom.server.entity.*;
import net.minestom.server.entity.metadata.PlayerMeta;
import net.minestom.server.network.packet.server.play.EntityMetaDataPacket;
import net.minestom.server.network.packet.server.play.PlayerInfoRemovePacket;
import net.minestom.server.network.packet.server.play.PlayerInfoUpdatePacket;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.ArrayList;
import java.util.Map;

@SuppressWarnings("UnstableApiUsage")
public class NPC extends Entity {
    private final String username;

    private final String skinTexture;
    private final String skinSignature;

    public NPC(@NotNull String username, @Nullable String skinTexture, @Nullable String skinSignature) {
        super(EntityType.PLAYER);
        this.username = username;
        setCustomName(Component.text(username));

        this.skinTexture = skinTexture;
        this.skinSignature = skinSignature;

        setNoGravity(true);
    }

    @Override
    public void updateNewViewer(@NotNull Player player) {
        var properties = new ArrayList<PlayerInfoUpdatePacket.Property>();
        if (skinTexture != null && skinSignature != null) {
            properties.add(new PlayerInfoUpdatePacket.Property("textures", skinTexture, skinSignature));
        }
        var entry = new PlayerInfoUpdatePacket.Entry(getUuid(), username, properties, false,
                0, GameMode.SURVIVAL, null, null);
        player.sendPacket(new PlayerInfoUpdatePacket(PlayerInfoUpdatePacket.Action.ADD_PLAYER, entry));

        // Spawn the player entity
        super.updateNewViewer(player);
        setSkin();
        player.sendPackets(new EntityMetaDataPacket(getEntityId(), Map.of(17, Metadata.Byte((byte) 127))));
    }

    @Override
    public void updateOldViewer(@NotNull Player player) {
        super.updateOldViewer(player);

        player.sendPacket(new PlayerInfoRemovePacket(getUuid()));
    }

    public void setSkin() {
        PlayerMeta meta = (PlayerMeta) this.entityMeta;

        // Nice and pretty second layer
        meta.setNotifyAboutChanges(false);
        meta.setCapeEnabled(true);
        meta.setHatEnabled(true);
        meta.setJacketEnabled(true);
        meta.setLeftLegEnabled(true);
        meta.setRightLegEnabled(true);
        meta.setLeftSleeveEnabled(true);
        meta.setRightSleeveEnabled(true);
        meta.setNotifyAboutChanges(true);
    }
}