package ij.plugin;
import ij.*;
import ij.process.*;
import ij.gui.*;
import java.awt.*;
import ij.io.*;
import java.net.URL;
import java.awt.image.*;

    /** This plugin implements the Help/About ImageJ command by opening
     * about.jpg in ij.jar, scaling it 600% and adding text to an overlay.
    */
    public class AboutBox implements PlugIn {
        private static final int SMALL_FONT=20, LARGE_FONT=45;
        private static final Color TEXT_COLOR = new Color(255,255,80);

    public void run(String arg) {
        System.gc();
        int lines = 7;
        String[] text = new String[lines];
        text[0] = "ImageJ "+ImageJ.VERSION+ImageJ.BUILD;
        text[1] = "Wayne Rasband and contributors";
        text[2] = "National Institutes of Health, USA";
        text[3] = IJ.URL;
        text[4] = "Java "+System.getProperty("java.version")+(IJ.is64Bit()?" (64-bit)":" (32-bit)");
        text[5] = IJ.freeMemory();
        text[6] = "ImageJ is in the public domain";
        ImageProcessor ip = null;
        ImageJ ij = IJ.getInstance();
        URL url = ij .getClass() .getResource("/about.jpg");
        if (url!=null) {
            Image img = null;
            try {img = ij.createImage((ImageProducer)url.getContent());}
            catch(Exception e) {}
            if (img!=null) {
                ImagePlus sImp = new ImagePlus("", img);
                ip = sImp.getProcessor();
            }
        }
        if (ip==null) 
            ip =  new ColorProcessor(55,45);
        ip = ip.resize(ip.getWidth()*6, ip.getHeight()*6);
        ImagePlus imp = new ImagePlus("About ImageJ", ip);
        int width = imp.getWidth();
        Overlay overlay = new Overlay();
        Font font = new Font("SansSerif", Font.PLAIN, LARGE_FONT);
        int y  = 60;
        add(text[0], width-20, y, font, TextRoi.RIGHT, overlay);
        int xcenter = 410;
        font = new Font("SansSerif", Font.PLAIN, SMALL_FONT);
        y += 45;
        add(text[1], xcenter, y, font, TextRoi.CENTER, overlay);
        y += 27;
        add(text[2], xcenter, y, font, TextRoi.CENTER, overlay);
        y += 27;
        add(text[3], xcenter, y, font, TextRoi.CENTER, overlay);
        y += 27;
        add(text[4], xcenter, y, font, TextRoi.CENTER, overlay);
        if (IJ.maxMemory()>0L) {
            y += 27;
            add(text[5], xcenter, y, font, TextRoi.CENTER, overlay);
        }
        add(text[6], width-10, ip.getHeight()-10, font, TextRoi.RIGHT, overlay);
        imp.setOverlay(overlay);
        ImageWindow.centerNextImage();
        imp.show();
    }
    
    private void add(String text, int x, int y, Font font, int justification, Overlay overlay) {
        TextRoi roi = new TextRoi(text, x, y, font);
        roi.setStrokeColor(TEXT_COLOR);
        roi.setJustification(justification);
        overlay.add(roi);
    }

}