/*

 * Copyright (c) 2007, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.swingset3.demos.spinner;

import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.awt.geom.Point2D;

import java.awt.image.BufferedImage;

import java.awt.image.DataBufferInt;

import java.util.List;

import com.sun.swingset3.demos.ResourceManager;

/**

 * @author Mikhail Lapshin

 */

public class JMandelbrot extends JComponent {

    private static final double EPSILON = 1E-16;

    private static final int MIN_WIDTH = 50;

    private static final int MIN_HEIGHT = 50;

    private static final double ZOOM_RATE = 3;

    private static final int NUM_OF_THREADS = 4;

    private Point2D center;

    public static final String CENTER_PROPERTY_NAME = "center";

    private int maxIteration = 300;

    public static final String MAX_ITERATION_PROPERTY_NAME = "maxIteration";

    private Palette palette;

    public static final String PALETTE_PROPERTY_NAME = "palette";

    private BufferedImage buffer;

    private final MandelbrotCalculator[] calculators

            = new MandelbrotCalculator[NUM_OF_THREADS];

    private double xLowLimit = -2;

    private double xHighLimit = 2;

    private double yLowLimit = -2;

    private double yHighLimit = 2;

    private double xScale = 100;

    private double yScale = 100;

    private int oldComponentWidth = (int) (xScale * (xHighLimit - xLowLimit));

    private int oldComponentHeight = (int) (yScale * (yHighLimit - yLowLimit));

    public JMandelbrot(int width, int height, Palette palette,

            ResourceManager resourceManager) {

        setPreferredSize(new Dimension(width, height));

        setMinimumSize(new Dimension(MIN_WIDTH, MIN_HEIGHT));

        calcConstants(width, height);

        setPalette(palette);

        setToolTipText(resourceManager.getString("SpinnerDemo.toolTip"));

        installListeners();

    }

    private void calcConstants() {

        calcConstants(getWidth(), getHeight());

    }

    private void calcConstants(int width, int height) {

        if ((width >= MIN_WIDTH) && (height >= MIN_HEIGHT)) {

            double oldIntervalWidth = xHighLimit - xLowLimit;

            double oldIntervalHeight = yHighLimit - yLowLimit;

            double newIntervalWidth

                    = width * oldIntervalWidth / oldComponentWidth;

            double newIntervalHeight

                    = height * oldIntervalHeight / oldComponentHeight;

            double xDiff = newIntervalWidth - oldIntervalWidth;

            double yDiff = newIntervalHeight - oldIntervalHeight;

            xLowLimit -= xDiff / 2;

            xHighLimit += xDiff / 2;

            yLowLimit -= yDiff / 2;

            yHighLimit += yDiff / 2;

            buffer = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

            oldComponentWidth = width;

            oldComponentHeight = height;

            setCenter(calcCenter());

        }

    }

    private void installListeners() {

        addMouseListener(new MouseAdapter() {

            @Override

            public void mousePressed(MouseEvent e) {

                int xCoord = e.getX();

                int yCoord = e.getY();

                double intervalWidth = xHighLimit - xLowLimit;

                double intervalHeight = yHighLimit - yLowLimit;

                double x = intervalWidth * xCoord / getWidth() + xLowLimit;

                double y = intervalHeight * yCoord / getHeight() + yLowLimit;

                double newIntervalWidth;

                double newIntervalHeight;

                if (e.getButton() == MouseEvent.BUTTON1) {

                    boolean limitReached = false;

                    newIntervalWidth = intervalWidth / ZOOM_RATE;

                    if ((newIntervalWidth / getWidth()) < EPSILON) {

                        newIntervalWidth = intervalWidth;

                        limitReached = true;

                    }

                    newIntervalHeight = intervalHeight / ZOOM_RATE;

                    if ((newIntervalHeight / getHeight()) < EPSILON) {

                        newIntervalHeight = intervalHeight;

                        limitReached = true;

                    }

                    if (!limitReached) {

                        xLowLimit = x - (x - xLowLimit) / ZOOM_RATE;

                        yLowLimit = y - (y - yLowLimit) / ZOOM_RATE;

                    }

                } else {

                    newIntervalWidth = intervalWidth * ZOOM_RATE;

                    newIntervalHeight = intervalHeight * ZOOM_RATE;

                    xLowLimit = x - (x - xLowLimit) * ZOOM_RATE;

                    yLowLimit = y - (y - yLowLimit) * ZOOM_RATE;

                }

                xHighLimit = xLowLimit + newIntervalWidth;

                yHighLimit = yLowLimit + newIntervalHeight;

                setCenter(calcCenter());

                xScale = getWidth() / newIntervalWidth;

                yScale = getHeight() / newIntervalHeight;

                calculatePicture();

            }

        });

        addComponentListener(new ComponentListener() {

            @Override

            public void componentResized(ComponentEvent e) {

                calcConstants();

                calculatePicture();

                repaint();

            }

            @Override

            public void componentMoved(ComponentEvent e) {

            }

            @Override

            public void componentShown(ComponentEvent e) {

            }

            @Override

            public void componentHidden(ComponentEvent e) {

            }

        });

    }

    //<snip>Use SwingWorker to asynchronously calculate parts of the picture

    public void calculatePicture() {

        int yStep = getHeight() / NUM_OF_THREADS;

        int yStart = 0;

        for (int i = 0; i < calculators.length; i++) {

            if ((calculators[i] != null) && !calculators[i].isDone()) {

                calculators[i].cancel(true);

            }

            int yEnd = i == calculators.length - 1 ? getHeight() : yStart + yStep;

            calculators[i] = new MandelbrotCalculator(yStart, yEnd);

            calculators[i].execute();

            yStart = yEnd;

        }

    }

    //</snip>

    private Point2D calcCenter() {

        return new Point2D.Double(xLowLimit + (xHighLimit - xLowLimit) / 2,

                yLowLimit + (yHighLimit - yLowLimit) / 2);

    }

    @Override

    protected void paintComponent(Graphics g) {

        super.paintComponent(g);

        g.drawImage(buffer, 0, 0, null);

    }

    //<snip>Use SwingWorker to asynchronously calculate parts of the picture

    private class MandelbrotCalculator extends SwingWorker<Object, Object> {

        private final int yStart;

        private final int yEnd;

        public MandelbrotCalculator(int yStart, int yEnd) {

            this.yStart = yStart;

            this.yEnd = yEnd;

        }

        @Override

        protected Object doInBackground() throws Exception {

            int[] data = ((DataBufferInt) buffer.getRaster().getDataBuffer()).getData();

            double xArr[] = new double[buffer.getWidth()];

            for (int i = 0; i < xArr.length; i++) {

                xArr[i] = i / xScale + xLowLimit;

            }

            double yArr[] = new double[yEnd - yStart];

            for (int i = 0; i < yArr.length; i++) {

                yArr[i] = (yStart + i) / yScale + yLowLimit;

            }

            int i = yStart * buffer.getWidth();

            for (double y : yArr) {

                for (double x : xArr) {

                    int value = calcValue(x, y);

                    data[i] = value == maxIteration ? 0 : palette.getRgbColor(value);

                    i++;

                }

                if (Thread.currentThread().isInterrupted()) {

                    return null;

                }

                publish();

            }

            return null;

        }

        private int calcValue(double x, double y) {

            double x0 = x;

            double y0 = y;

            for (int i = 0; i < maxIteration; i++) {

                double x2 = x * x;

                double y2 = y * y;

                if (x2 + y2 > 4) {

                    return i;

                }

                y = 2 * x * y + y0;

                x = x2 - y2 + x0;

            }

            return maxIteration;

        }

        @Override

        protected void process(List<Object> chunks) {

            repaint();

        }

    }

    //</snip>

    // Getters and Setters

    public int getMaxIteration() {

        return maxIteration;

    }

    public void setMaxIteration(int maxIteration) {

        int oldValue = this.maxIteration;

        this.maxIteration = maxIteration;

        firePropertyChange(MAX_ITERATION_PROPERTY_NAME, oldValue, maxIteration);

        palette.setSize(maxIteration);

    }

    public double getXHighLimit() {

        return xHighLimit;

    }

    public double getXLowLimit() {

        return xLowLimit;

    }

    public double getYLowLimit() {

        return yLowLimit;

    }

    public double getYHighLimit() {

        return yHighLimit;

    }

    public Point2D getCenter() {

        return center;

    }

    public void setCenter(Point2D coords) {

        Point2D oldValue = this.center;

        this.center = coords;

        double width = xHighLimit - xLowLimit;

        double height = yHighLimit - yLowLimit;

        xLowLimit = coords.getX() - width / 2;

        xHighLimit = xLowLimit + width;

        yLowLimit = coords.getY() - height / 2;

        yHighLimit = yLowLimit + height;

        firePropertyChange(CENTER_PROPERTY_NAME, oldValue, coords);

    }

    public Palette getPalette() {

        return palette;

    }

    public void setPalette(Palette palette) {

        Palette oldValue = this.palette;

        palette.setSize(maxIteration);

        this.palette = palette;

        firePropertyChange(PALETTE_PROPERTY_NAME, oldValue, palette);

    }

}