/**
 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(' ');
    }
}