/**
 * Write a description of class MandelbrotGenerator here.
 *
 * @author (your name)
 * @version (a version number or a date)
 */

import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.util.Duration;

import javafx.scene.input.KeyCode;
import javafx.animation.Animation;

public class MandelbrotGenerator extends Application
{
    // intstance variables
    static final int screenWidth = 900;
    static final int screenHeight = 450;

    static final int scale = 0;
    static final int maxIterations = 255;

    @Override
    public void start(Stage stage)
    {
        Canvas canvas = new Canvas(screenWidth, screenHeight);
        GraphicsContext gc = canvas.getGraphicsContext2D();
        Timeline tl = new Timeline(new KeyFrame(Duration.millis(100), e -> run(gc)));
        tl.setCycleCount(Timeline.INDEFINITE);
        canvas.setFocusTraversable(true);

        // handle mouse and key events
        canvas.setOnKeyPressed(e ->
            {
                if(e.getCode() == KeyCode.W)
                {
                    // do something
                }
            });

        canvas.setOnMouseClicked(e ->
            {
                // do something
            });

        stage.setTitle("Mandelbrot Set Generator");
        stage.setScene(new Scene(new StackPane(canvas)));
        stage.show();
        tl.play();
    }

    private void run(GraphicsContext gc)
    {
        // color for background
        gc.setFill(Color.BLACK);
        gc.fillRect(0, 0, screenWidth, screenHeight);

        for (int row = 0; row < screenWidth; row++) {
        	for (int col = 0; col < screenHeight; col++) {
        		checkPoint(row, col, gc);
        	}
        }



    }
    //determinees number of iterations, calls colorPoint if in set
    public static void checkPoint(int x, int y, GraphicsContext gc) {
    	int numIterations = 0;
    	int previousSum = 0;
    	int c = getDistanceSquared(x, y);

    	while (numIterations < maxIterations && previousSum < 4) {
    		previousSum = zFuntionOutput(c, previousSum);
    	}
    	System.out.println("here");
    	if (numIterations < maxIterations)
    		colorPoint(x, y, numIterations, gc);
    }

    //draw and assign color
    public static void colorPoint(int x, int y, double iterations, GraphicsContext gc) {
        iterations = 1 / (iterations + 1);
    	gc.setFill(new Color(iterations, 1 - iterations, iterations, 1));
    	gc.fillRect(x, y, 1, 1);
    }

    public static int zFuntionOutput(int c, int previousSum) {
    	return previousSum * previousSum + c;
    }

    //
    public static int getDistanceSquared(int x, int y) {
    	return translateX(x) * translateX(x) + translateY(y) * translateY(y);
    }



    /*
	@param: takes the X value fromt the top left coordinate system
	@postcondition: returns the X coordinate on the cartesian cooridnate system
    */
     public static int translateX(int x) {
        if (x < screenWidth / 2) {
            return x - screenWidth / 2;
        }
        else if (x > screenWidth / 2) {
            return x / 2;
        }
        else {
            return 0;
        }
    }

    /*
	@param: takes the Y value fromt the top left coordinate system
	@postcondition: returns the Y coordinate on the cartesian cooridnate system
    */
    public static int translateY(int y) {
        if (y < screenHeight / 2) {
            return y + screenHeight / 2;
        }
        else if (y > screenHeight / 2) {
            return -y / 2;
        }
        else {
            return 0;
        }
    }

    // run program
    public static void main(String[] args)
    {
        Application.launch(args);
    }

}