/*
 *            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
 *                    Version 2, December 2004
 *
 * Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
 *
 * Everyone is permitted to copy and distribute verbatim or modified
 * copies of this license document, and changing it is allowed as long
 * as the name is changed.
 *
 *            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
 *   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
 *
 *  0. You just DO WHAT THE FUCK YOU WANT TO.
 *
 */
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Image;
import java.awt.Point;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.DataBufferInt;
import java.awt.image.Raster;
import java.io.File;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.swing.JComponent;
import javax.swing.JFrame;

final class NoiseGen {

    private NoiseGen() {
    }

    public static void main(String[] args) {
        final int w = 768;
        final int h = 768;
        final int alpha = 60;

        var buffer = new DataBufferInt(
            new Random().ints(w * h).parallel()
                .map(x -> (x & (alpha << 24)))
                .toArray(),
            w * h);

        var raster = Raster.createPackedRaster(
            buffer,
            w, h, w,
            // ARGB
            new int[] { 0x00FF0000, 0x0000FF00, 0x000000FF, 0xFF000000 },
            new Point(0, 0));

        var img = new BufferedImage(ColorModel.getRGBdefault(), raster,
            false, null);

        preview(img);

        try {
            ImageIO.write(img, "PNG", new File("noise.png"));
        } catch (IOException exception) {
            exception.printStackTrace();
        }
    }

    private static void preview(Image img) {
        int w = img.getWidth(null);
        int h = img.getHeight(null);

        var contentPane = new JComponent() {

            private static final long serialVersionUID = 1L;

            public void paint(java.awt.Graphics g) {
                g.drawImage(img,
                    ((getWidth() - w) >> 1),
                    ((getHeight() - h) >> 1),
                    this);
            };

        };
        contentPane.setPreferredSize(new Dimension(w + 10, h + 10));
        contentPane.setSize(w + 10, h + 10);

        var frame = new JFrame("Preview");
        frame.setDefaultCloseOperation(3);
        frame.setBackground(Color.WHITE);
        frame.setContentPane(contentPane);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

}