//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//A Simple Fractal
//Description: Draws a Sierpinski Triangle with a square for a starting shape.
//CS 284
//Programmed by Jonathan Voris
//for 1/24/06
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

//for graphics usage
import java.awt.*;
//for keyboard input
import java.util.Scanner;

//the fractal class extends Frame to use its window calls
class fractal extends Frame
{
	private int windowSize = 700;
	private int numSteps = 1;

	public static void main(String[] args)
	{
		//call fractal's constructor
		fractal fract = new fractal();
		//start the fractal drawing process
		fract.run();
	}

	//fractal constructor creates a window by calling Frame methods
    public fractal()
    {
		//window title
		setTitle("Sierpinski Triangle");
		//window location
		setLocation(0, 0);
		//window size
		setSize(windowSize, windowSize);
		//background color of the window
		setBackground(Color.white);
		//make the window appear
		setVisible(true);
    }

	//run performs the fractal's drawing process
    private void run()
    {
		//create a new scanner for reading keyboard input
		Scanner sc = new Scanner(System.in);

		//loop continuously
		while (true)
		{
			//input the number of steps of the fractal to draw
			System.out.print("Please input the number of steps to use:");
			numSteps = sc.nextInt();
			System.out.println();

			// ask window system to call paint() to draw fractal with
			// the new number of steps
			repaint();

		}
	}

	public void paint(Graphics g)
	{
		g.setColor(Color.black);
		//initial call to drawFract - start with g, which is necessary for graphics output,
		//the inputted number of steps, and the desired overall fractal size. Using
		//0, 0, windowSize will create a fractal that takes up the whole graphics window.
		drawFract(g, numSteps, 0, 0, windowSize);
    }

	//drawFract accepts a graphics object, the number of times of detail to repeat in the fractal
	//pattern, square coordinates and a square size as input. It recursively calls itself,
	//further subdividing the fractal each time. This continues until the desired level of detail
	//has been exhausted, at which point a properly sized shape is drawn.
    private void drawFract(Graphics g, int numSteps, int squareX, int squareY, double squareSize)
    {
		//Base case - if the function is called with 1 for numSteps, no further level of detail
		//is needed.
		if (numSteps == 1)
		{
			//Draw a rectangle with the given coordinates and size.
			g.fillRect(squareX, squareY, (int)squareSize, (int)squareSize);
			//(I left the following line commented out since the starting shape used does not
			//affect the shape produced by the fractal.)
			//g.fillOval(squareX, squareY, (int)squareSize, (int)squareSize);
		}
		//Recursion - if more steps of detail are required, then recursively call drawFact
		//three times - one for each subobject to be drawn
		else
		{
			//draw a fractal in the top-middle of the current fractal space
			drawFract(g, numSteps-1, squareX + (int)squareSize/4,  squareY + 0, squareSize/2);
			//draw a fractal in the bottom-left of the current fractal space
			drawFract(g, numSteps-1, squareX + 0, squareY + (int)squareSize/2, squareSize/2);
			//draw a fractal in the bottom-right of the current fractal space
			drawFract(g, numSteps-1, squareX + (int)squareSize/2, squareY + (int)squareSize/2, squareSize/2);
		}
	}
}