import java.awt.Color;
import java.text.NumberFormat;
import javax.swing.JOptionPane;

import uwcse.graphics.GWindow;
import uwcse.graphics.Oval;
import uwcse.graphics.Rectangle;
import uwcse.io.Input;

public class PracticeWithLoops {

	public static void main(String[] args) {
		// interestCalculator();
		// figureOfStars();
		// sum35();
		displayMandelbrotSet();
	}

	/**
	 * Displays a triangle of stars
	 */
	public static void figureOfStars() {
		Input in = new Input();
		int lines;
		do {
			lines = in.readInt("Number of lines (or 0 to stop): ");
			for (int j = 1; j <= lines; j++) {
				// a line of lines - j spaces
				for (int i = 1; i <= lines - j; i++) {
					System.out.print(" ");
				}

				// a line of j stars
				for (int i = 1; i <= j; i++) {
					System.out.print("*");
				}
				System.out.println();
			}
		} while (lines != 0); // 0 is the sentinel value
	}

	/**
	 * Number of years needed to double a money amount given an interest rate
	 */
	public static void interestCalculator() {
		Input in = new Input();
		NumberFormat nf = NumberFormat.getCurrencyInstance();
		char answer;
		do {
			// read the interest rate
			double rate = in
					.readDouble("Enter the interest rate (as a percentage): ");
			// compute the number of years
			double amount = 1000;
			int year = 0;
			while (amount <= 2000) {
				amount *= 1 + rate / 100;
				year++;
			}
			System.out.println("Number of years = " + year);
			System.out.println("Amount = " + nf.format(amount));
			answer = in.readChar("Again (y or n)? ");
		} while (answer == 'y');

	}

	/**
	 * Sums all of the natural numbers below 1000 that are multiple of 5 or 3
	 */
	public static void sum35() {
		int sum = 0;
		for (int i = 3; i < 1000; i++) {
			if (i % 3 == 0 || i % 5 == 0) {
				sum += i;
			}
		}
		System.out.println("Sum = " + sum);
	}

	public static void displayMandelbrotSet() {
		GWindow w = new GWindow();
		w.setExitOnClose();
		double xmin = -1.5;
		double xmax = 0.5;
		double ymin = -1;
		double ymax = +1;
		for (int i = 0; i < w.getWindowWidth(); i++) {
			for (int j = 0; j < w.getWindowHeight(); j++) {
				double x = xmin + (xmax - xmin) * i / w.getWindowWidth();
				double y = ymax - (ymax - ymin) * j / w.getWindowHeight();
				Color c = getMandelbrotColor(x, y);
				Rectangle o = new Rectangle(i, j, 1, 1, c, true);
				w.add(o);
			}
			w.doRepaint();
		}
	}

	public static Color getMandelbrotColor(double x, double y) {
		double x0 = 0, y0 = 0;
		double x1, y1;
		int count = 0;
		do {
			x1 = x0 * x0 - y0 * y0 + x;
			y1 = 2 * x0 * y0 + y;
			x0 = x1;
			y0 = y1;
			count++;
		} while (count < 256 && x1 * x1 + y1 * y1 < 4);

		if (count > 240) {
			return Color.BLACK;
		} else if (count < 20) {
			return Color.BLUE;
		} else {
			int red = 255 - count;
			int green = 255 - count;
			int blue = 255 - count;
			return new Color(red, green, blue);
		}

	}

}