package class9_3_VehicleFunctions_start;

public abstract class Vehicle {
    public static final int DEFAULT_NORTH_METERS_PER_SEC = 4;

    /** The car's position */
    private double northMeters = 0;

    /** The car's speed */
    private double northMetersPerSec;

    /** Create a car at the specied position with the specified initial velocity
     *
     * @param northMeters position north of game center of vehicle's center of mass
     * @param northMetersPerSec velocity north of game center of vehicle's
     *                          center of mass, in m/s.
     */
    public Vehicle(double northMeters, double northMetersPerSec) {
        this.northMeters = northMeters;
        this.northMetersPerSec = northMetersPerSec;
    }

    /**
     * Create a car at the specified position.
     * The vehicle will be moving north by default at about 10mph
     * @param northMeters position north of game center of vehicle's center of mass
     */
    public Vehicle(double northMeters) {
        this(northMeters, DEFAULT_NORTH_METERS_PER_SEC);
    }

    public double getNorthMeters() {
        return northMeters;
    }

    public double getNorthMetersPerSec() {
        return northMetersPerSec;
    }

    /**
     * Step forward the simulation by one second.
     */
    public void step() {
        northMeters += northMetersPerSec;
    }

    @Override
    public abstract String toString();

    @Override
    public boolean equals(Object object) {
        if(!(object instanceof Vehicle)) {
            return false;
        }
        Vehicle other = (Vehicle)object;
        return this.northMeters == other.northMeters
                && this.northMetersPerSec == other.northMetersPerSec;
    }

    @Override
    public int hashCode() {
        return Double.hashCode(northMeters) + Double.hashCode(northMetersPerSec);
    }
}