/**
 * A class for representing a rectangle. This class contains no static attributes and no static methods. 
 * 
 * @author Franck van Breugel
 */
public class Rectangle
{
    private int width;
    private int height;
    
    /**
     * Initializes this rectangle with the given width and height. 
     * 
     * @param width the width of this rectangle.
     * @pre. width >= 0
     * @param height the height of this rectangle.
     * @pre. height >= 0
     */
    public Rectangle(int width, int height)
    {
	this.width = width;
	this.height = height;
    }

    /**
     * Initializes this rectangle with zero width and height. 
     */
    public Rectangle()
    {
	this.width = 0;
	this.height = 0;
    }
    
    /**
     * Initializes this rectangle with the same width and height as the given rectangle. 
     * 
     * @param rectangle the rectangle to be copied.
     */
    public Rectangle(Rectangle rectangle)
    {
	this.width = rectangle.width;
	this.height = rectangle.height;
    }

    /**
     * Returns the width of this rectangle. 
     * 
     * @return the width the width of this rectangle. 
     */
    public int getWidth()
    {
	return this.width;
    }

    /**
     * Sets the width of this rectangle to the given width. 
     * 
     * @param width the width of this rectangle.
     * @pre. width >= 0
     */
    public void setWidth(int width)
    {
	this.width = width;
    }

    /**
     * Returns the height of this rectangle. 
     * 
     * @return the height of this rectangle. 
     */
    public int getHeight()
    {
	return this.height;
    }

    /**
     * Sets the height of this rectangle to the given height. 
     * 
     * @param height the height of this rectangle.
     * @pre. height >= 0
     */
    public void setHeight(int height)
    {
	this.height = height;
    }
    
    /**
     * Returns the area of this rectangle. 
     * 
     * @return the area of this rectangle. 
     */
    public int getArea()
    {
	return this.width * this.height;
    }
    
    /**
     * Returns a string representation of this rectangle. 
     * For example, the string representation of new Rectangle(1, 2) 
     * is "Rectangle of width 1 and height 2". 
     * 
     * @return a string representation of this rectangle.
     */
    public String toString()
    {
	return "Rectangle of width " + this.width + " and height " + this.height;
    }
    
    /**
     * Scales this rectangle with the given factor. 
     * 
     * @param factor the scaling factor.
     * @pre. factor >= 0
     */
    public void scale(int factor)
    {
	this.width = this.width * factor;
	this.height = this.height * factor;
    }

    /**
     * Tests if this rectangle is the same as the given object. 
     * Two rectangles are considered the same if they have the 
     * same width and height.
     * 
     *  @param object an object.
     *  @return true if this rectangle is the same as the given 
     *  object, false otherwise.
     */
    public boolean equals(Object object)
    {
	boolean equal;
	if (object != null && this.getClass() == object.getClass())
	{
	    Rectangle other = (Rectangle) object;
	    equal = this.width == other.width && this.height == other.height;
	}
	else
	{
	    equal = false;
	}
	return equal;
    }

    /**
     * Compares two rectangles. This rectangle is smaller than another 
     * rectangle if its width is smaller than the width of the other 
     * rectangle, or the width of the rectangles is the same and the 
     * height of this rectangle is smaller than the height of the other 
     * rectangle. 
     * 
     * @param other another rectangle.
     * @return 0 if this rectangle is equal to the other rectangle; a 
     * value less than 0 if this rectangle is smaller than the other 
     * rectangle; a value greater than 0 otherwise.
     */
    public int compareTo(Rectangle other)
    {
	int difference;
	if (this.width == other.width)
	{
	    difference = this.height - other.height;
	}
	else
	{
	    difference = this.width - other.width;
	}
	return difference;
    }
}