ModernUO/Projects/UOContent/Items/Games/BasePiece.cs

namespace Server.Items
{
    public class BasePiece : Item
    {
        public BasePiece(int itemID, BaseBoard board) : base(itemID) => Board = board;

        public BasePiece(Serial serial) : base(serial)
        {
        }

        public BaseBoard Board { get; set; }

        public override bool IsVirtualItem => true;

        public override bool CanTarget => false;

        public override void Serialize(IGenericWriter writer)
        {
            base.Serialize(writer);

            writer.Write(0);
            writer.Write(Board);
        }

        public override void Deserialize(IGenericReader reader)
        {
            base.Deserialize(reader);

            var version = reader.ReadInt();

            switch (version)
            {
                case 0:
                    {
                        Board = (BaseBoard)reader.ReadEntity<Item>();

                        if (Board == null || Parent == null)
                        {
                            Delete();
                        }

                        break;
                    }
            }
        }

        public override void OnSingleClick(Mobile from)
        {
            if (Board?.Deleted != false)
            {
                Delete();
            }
            else if (!IsChildOf(Board))
            {
                Board.DropItem(this);
            }
            else
            {
                base.OnSingleClick(from);
            }
        }

        public override bool OnDragLift(Mobile from)
        {
            if (Board?.Deleted != false)
            {
                Delete();
                return false;
            }

            if (!IsChildOf(Board))
            {
                Board.DropItem(this);
                return false;
            }

            return true;
        }

        public override bool DropToMobile(Mobile from, Mobile target, Point3D p) => false;

        public override bool DropToItem(Mobile from, Item target, Point3D p) =>
            target == Board && p.X != -1 && p.Y != -1 && base.DropToItem(from, target, p);

        public override bool DropToWorld(Mobile from, Point3D p) => false;

        public override int GetLiftSound(Mobile from) => -1;
    }
}