import java.util.ArrayList;
import java.util.Random;

public class EntityWithRollers<T extends EntityTracktor, U extends IDrawningRollers> {
    static Random rnd = new Random();
    private ArrayList<T> entities;
    private ArrayList<U> rollers;

    public int maxEntitiesCount = 0;
    public int maxRollersCount = 0;

    public EntityWithRollers(int count) {
        entities = new ArrayList<T>();
        rollers = new ArrayList<U>();
        maxEntitiesCount = count;
        maxRollersCount = count;
    }

    public boolean add(T entity) {
        if (entities.size() >= maxEntitiesCount){
            return false;
        }
        entities.add(entity);
        return true;
    }

    public boolean add(U roller) {
        if (rollers.size() >= maxRollersCount){
            return false;
        }
        rollers.add(roller);
        return true;
    }

    public IDrawningObject constructTracktor() {
        if (entities.size() == 0 || rollers.size() == 0) {
            return null;
        }

        EntityTracktor entity = (EntityTracktor) entities.get(rnd.nextInt(0, entities.size()));
        IDrawningRollers roller = (IDrawningRollers) rollers.get(rnd.nextInt(0, rollers.size()));

        if (entity instanceof EntityTrackedVehicle advancedEntity) {
            return new DrawningObjectExcavator(new DrawningTrackedVehicle(advancedEntity, roller));
        }
        return new DrawningObjectExcavator(new DrawningTracktor(entity, roller));
    }
}