/**
 * A <tt>RectangularPrism</tt> has three dimensions: length,
 * height and depth.
 */
public final class RectangularPrism extends Rectangle
implements Cloneable, ThreeD {

    private double depth;

    /**
      * Construct a <tt>RectangularPrism</tt> object using the
      * default size for its dimensions.
      */
     public RectangularPrism() {
      this(Shape.DEFAULT_SIZE, Shape.DEFAULT_SIZE,
             Shape.DEFAULT_SIZE);
    }

    /**
     * Construct a <tt>RectangularPrism</tt> object using the
     * arguments. If an argument is <= 0, the default size
     * specified in <tt>Shape</tt> is used instead.
     * @param theLength length of this <tt>RectangularPrism</tt>;
     *         must be > 0
     * @param theHeight height of this <tt>RectangularPrism</tt>;
     *         must be > 0
     * @param theDepth depth of this <tt>RectangularPrism</tt>;
     *        must be > 0
     */
    public RectangularPrism( double theLength, double theHeight,
                             double theDepth ) {
        setShapeName( "Rectangular Prism" );
        if ( theLength <= 0.0 )
          setLength( Shape.DEFAULT_SIZE );
        else
          setLength( theLength );

        if ( theHeight <= 0.0 )
          setHeight( Shape.DEFAULT_SIZE );
        else
          setHeight( theHeight );

        if ( theDepth <= 0.0 )
          setDepth( Shape.DEFAULT_SIZE );
        else
          setDepth( theDepth );
    }

    /**
     * Construct a <tt>RectangularPrism</tt> object using the
     * arguments. If an argument is <= 0, the default size
     * specified in <tt>Shape</tt> is used instead.
     * Solution to CheckPoint 1.11, Chapter 1.
     * @param theRect contains length and height; cannot be null
     * @param theDepth double the depth should be > 0.0
     * @throws NullPointerException if <tt>r</tt> is <tt>null</tt>
     */
    public RectangularPrism( Rectangle theRect, double theDepth ) {
      if ( theRect == null )
          throw new NullPointerException();

        setLength( theRect.getLength() );
        setHeight( theRect.getHeight() );
        if ( theDepth <= 0.0 )
           setDepth( Shape.DEFAULT_SIZE );
         else
           setDepth( theDepth );
    }

    /**
     * Get the surface area of this <tt>RectangularPrism</tt>.
     * Overridden method inherited from Rectangle.
     * @return the surface area of this <tt>RectangularPrism</tt>
     */
    public double getSurfaceArea() {
        return  super.getSurfaceArea() * 2   // front and back
                + this.depth * getHeight() * 2    // sides
                + this.depth * getLength() * 2;  // top and bottom
    }

    /**
     * Get the perimeter of this <tt>RectangularPrism</tt>.
     * Overridden method inherited from Rectangle.
     * @return the perimeter of this <tt>RectangularPrism</tt>
     */
    public double getPerimeter() {
        return 2 * super.getPerimeter() + 4 * this.depth;
    }

    /* methods unique to RectPrism */

    /**
     * Get the volume of this <tt>RectangularPrism</tt>.
     * @return the volume of this <tt>RectangularPrism</tt>
     */
    public double getVolume() {
        return this.depth * getLength() * getHeight();
    }

    /**
     * Get the depth of this <tt>RectangularPrism</tt>.
     * @return the depth of this <tt>RectangularPrism</tt>
     */
    public double getDepth() {
        return this.depth ;
    }

    /**
     * Reset the depth of this <tt>RectangularPrism</tt>.
     * If <tt>theDepth</tt> is <= 0, the dimension is unchanged.
     * @param theDepth the new depth of this
     *        <tt>RectangularPrism</tt>; must be > 0
     */
    public void setDepth( double theDepth ) {
        if ( theDepth <= 0 )
            return;
        this.depth = theDepth;
    }


    /**
     * Returns a <tt>String</tt> object representing this
     * <tt>RectangularPrism</tt>'s value. Overridden from
     * <tt>Object</tt>.
     * @return a string representation of this object
     */
    public String toString() {
         return   super.toString() + ", depth = " + getDepth();
    }

    /**
     * Returns <tt>true</tt> if and only if the argument is not
     * <tt>null</tt> and is a <tt>RectangularPrism</tt> object that
     * represents the same rectangular prism value as this object.
     * The comparison is done based on the dimensions length,
     * height and depth.
     * @param o the object to compare with
     * @return <tt>true</tt> if the <tt>RectangularPrism</tt>
     * objects represent the same value; <tt>false</tt> otherwise.
     */
    public boolean equals( Object o ) {
       if ( ( o == null ) ||
            ( !( o instanceof RectangularPrism ) ) )
           return false;
       return super.equals( o ) &&
             ((RectangularPrism)o).getDepth() == this.getDepth();
    }

    /**
     * Make a clone of this <tt>RectangularPrism</tt>. Overridden
     * from <tt>Object</tt>.
     * @return Object a copy of this <tt>RectangularPrism</tt>.
     */
    public Object clone() {
        return super.clone();
    }
}