ZombieController.java

package net.citizensnpcs.nms.v1_15_R1.entity;

import org.bukkit.Bukkit;
import org.bukkit.craftbukkit.v1_15_R1.CraftServer;
import org.bukkit.craftbukkit.v1_15_R1.entity.CraftEntity;
import org.bukkit.craftbukkit.v1_15_R1.entity.CraftZombie;
import org.bukkit.entity.Zombie;
import org.bukkit.util.Vector;

import net.citizensnpcs.api.npc.NPC;
import net.citizensnpcs.nms.v1_15_R1.util.ForwardingNPCHolder;
import net.citizensnpcs.nms.v1_15_R1.util.NMSBoundingBox;
import net.citizensnpcs.nms.v1_15_R1.util.NMSImpl;
import net.citizensnpcs.npc.CitizensNPC;
import net.citizensnpcs.npc.ai.NPCHolder;
import net.citizensnpcs.util.NMS;
import net.citizensnpcs.util.Util;
import net.minecraft.server.v1_15_R1.AxisAlignedBB;
import net.minecraft.server.v1_15_R1.BlockPosition;
import net.minecraft.server.v1_15_R1.DamageSource;
import net.minecraft.server.v1_15_R1.Entity;
import net.minecraft.server.v1_15_R1.EntityBoat;
import net.minecraft.server.v1_15_R1.EntityMinecartAbstract;
import net.minecraft.server.v1_15_R1.EntityTypes;
import net.minecraft.server.v1_15_R1.EntityZombie;
import net.minecraft.server.v1_15_R1.FluidType;
import net.minecraft.server.v1_15_R1.IBlockData;
import net.minecraft.server.v1_15_R1.NBTTagCompound;
import net.minecraft.server.v1_15_R1.SoundEffect;
import net.minecraft.server.v1_15_R1.Tag;
import net.minecraft.server.v1_15_R1.Vec3D;
import net.minecraft.server.v1_15_R1.World;

public class ZombieController extends MobEntityController {
    public ZombieController() {
        super(EntityZombieNPC.class);
    }

    @Override
    public Zombie getBukkitEntity() {
        return (Zombie) super.getBukkitEntity();
    }

    public static class EntityZombieNPC extends EntityZombie implements NPCHolder {
        private final CitizensNPC npc;

        public EntityZombieNPC(EntityTypes<? extends EntityZombie> types, World world) {
            this(types, world, null);
        }

        public EntityZombieNPC(EntityTypes<? extends EntityZombie> types, World world, NPC npc) {
            super(types, world);
            this.npc = (CitizensNPC) npc;
        }

        @Override
        public void a(AxisAlignedBB bb) {
            super.a(NMSBoundingBox.makeBB(npc, bb));
        }

        @Override
        protected void a(double d0, boolean flag, IBlockData block, BlockPosition blockposition) {
            if (npc == null || !npc.isFlyable()) {
                super.a(d0, flag, block, blockposition);
            }
        }

        @Override
        public void a(Entity entity, float strength, double dx, double dz) {
            NMS.callKnockbackEvent(npc, strength, dx, dz, (evt) -> super.a(entity, (float) evt.getStrength(),
                    evt.getKnockbackVector().getX(), evt.getKnockbackVector().getZ()));
        }

        @Override
        public boolean b(float f, float f1) {
            if (npc == null || !npc.isFlyable()) {
                return super.b(f, f1);
            }
            return false;
        }

        @Override
        public boolean b(Tag<FluidType> tag) {
            return NMSImpl.fluidPush(npc, this, () -> super.b(tag));
        }

        @Override
        public void checkDespawn() {
            if (npc == null) {
                super.checkDespawn();
            }
        }

        @Override
        public void collide(net.minecraft.server.v1_15_R1.Entity entity) {
            // this method is called by both the entities involved - cancelling
            // it will not stop the NPC from moving.
            super.collide(entity);
            if (npc != null)
                Util.callCollisionEvent(npc, entity.getBukkitEntity());
        }

        @Override
        public boolean d(NBTTagCompound save) {
            return npc == null ? super.d(save) : false;
        }

        @Override
        public void e(Vec3D vec3d) {
            if (npc == null || !npc.isFlyable()) {
                super.e(vec3d);
            } else {
                NMSImpl.flyingMoveLogic(this, vec3d);
            }
        }

        @Override
        public void enderTeleportTo(double d0, double d1, double d2) {
            NMS.enderTeleportTo(npc,  () -> super.enderTeleportTo(d0, d1, d2));
        }

        @Override
        public CraftEntity getBukkitEntity() {
            if (npc != null && !(super.getBukkitEntity() instanceof NPCHolder)) {
                NMSImpl.setBukkitEntity(this, new ZombieNPC(this));
            }
            return super.getBukkitEntity();
        }

        @Override
        public NPC getNPC() {
            return npc;
        }

        @Override
        protected SoundEffect getSoundAmbient() {
            return NMSImpl.getSoundEffect(npc, super.getSoundAmbient(), NPC.Metadata.AMBIENT_SOUND);
        }

        @Override
        protected SoundEffect getSoundDeath() {
            return NMSImpl.getSoundEffect(npc, super.getSoundDeath(), NPC.Metadata.DEATH_SOUND);
        }

        @Override
        protected SoundEffect getSoundHurt(DamageSource damagesource) {
            return NMSImpl.getSoundEffect(npc, super.getSoundHurt(damagesource), NPC.Metadata.HURT_SOUND);
        }

        @Override
        public void h(double x, double y, double z) {
            Vector vector = Util.callPushEvent(npc, x, y, z);
            if (vector != null) {
                super.h(vector.getX(), vector.getY(), vector.getZ());
            }
        }

        @Override
        public boolean isClimbing() {
            if (npc == null || !npc.isFlyable()) {
                return super.isClimbing();
            } else {
                return false;
            }
        }

        @Override
        public boolean isLeashed() {
            return NMSImpl.isLeashed(npc, super::isLeashed, this);
        }

        @Override
        public void mobTick() {
            super.mobTick();
            if (npc != null) {
                NMSImpl.updateMinecraftAIState(npc, this);
                npc.update();
            }
        }

        @Override
        protected boolean n(Entity entity) {
            if (npc != null && (entity instanceof EntityBoat || entity instanceof EntityMinecartAbstract)) {
                return !npc.isProtected();
            }
            return super.n(entity);
        }
    }

    public static class ZombieNPC extends CraftZombie implements ForwardingNPCHolder {
        public ZombieNPC(EntityZombieNPC entity) {
            super((CraftServer) Bukkit.getServer(), entity);
        }
    }
}