//Triangle.java

/**
 * Class for drawing triangles on the screen using keyboard
 * characters. A triangle points up. Its size is determined
 * by the length of its base, which must be an odd integer. 
 * Inherits getOffset, setOffset, and drawAt from the class
 * ShapeBasics.
 */
public class Triangle
    extends ShapeBasics
    implements TriangleInterface
{
    private int base;

    public Triangle()
    {
        super();
        base = 0;
    }

    public Triangle
    (
        int theOffset,
        int theBase
    )
    {
        super(theOffset);
        base = theBase;
    }

    /**
     * Precondition: newBase is odd.
     */
    public void set
    (
        int newBase
    )
    {
        base = newBase;
    }

    /**
     * Draws the shape at current line.
     */
    public void drawHere()
    {
        drawTop();
        drawBase();
    }

    private void drawBase()
    {
        skipSpaces(getOffset());
        for (int count = 0; count < base; count++)
            System.out.print('*');
        System.out.println();
    }

    private void drawTop()
    {
        //startOfLine == number of spaces to the 
        //first '*' on a line. Initially set to the  
        //number of spaces before the topmost '*'.
        int startOfLine = getOffset() + base / 2;
        skipSpaces(startOfLine);
        System.out.println('*');//top '*'
        int lineCount = base / 2 - 1; //Height above base

        //insideWidth == number of spaces between the
        //two '*'s on a line.
        int insideWidth = 1;
        for (int count = 0; count < lineCount; count++)
        {
            //Down one line, so the first '*' is one more
            //space to the left.
            startOfLine--;
            skipSpaces(startOfLine);
            System.out.print('*');
            skipSpaces(insideWidth);
            System.out.println('*');

            //Down one line, so the inside is 2 spaces wider.
            insideWidth = insideWidth + 2;
        }
    }

    private static void skipSpaces
    (
        int number
    )
    {
        for (int count = 0; count < number; count++)
            System.out.print(' ');
    }
}