/*
 *                 Sun Public License Notice
 *
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 *
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.tasklist.core.translators;

import org.netbeans.modules.tasklist.core.translators.IconManager;

import java.io.File;
import java.util.HashMap;

import java.awt.*;
import java.awt.image.*;
import javax.imageio.*;
import javax.swing.ImageIcon;


/**
 * This class handles exporting icon gifs to a given directory
 * REQUIRES JDK14!
 * 

 * @author Tor Norbye
 */
class IconManager14 extends IconManager {

    private HashMap written = null;
    private File directory = null;
    private int nextId = 1;

    public IconManager14() {
    }

    /**
     * Set the base directory in which icon files are written.
     * Paths returned by getIcon are relative to this directory.
     */
    public void setBase(File base) {
        this.directory = base;
    }
    
    
    /**
     * Return the file name of the given icon, relative to
     * the directory that this IconManager was initialized with.
     * If the icon does not yet exist on disk, it is created first.
     * You MUST call setBase before the first call to this method.
     * @param icon The image we want a url for
     * @return A relative filename pointing to the image file
     */
    public String getIcon(Image icon) {
        if (written == null) {
            written = new HashMap(50);
        }
        
        String name = (String)written.get(icon);
        if (name == null) {
            // Invent filename for the icon. Can we use any tricks
            // here, if we pass in the node etc.?
            // For now, just use sequential naming
            BufferedImage image = toBufferedImage(icon);
            File output = null;
            // Find unused name
            while (true) {
                // Using PNG format - gif is probably more common, but
                // a gif writer often is not available in ImageIO
                name = "tasklist-html-" + (nextId++) + ".png"; // NOI18N
                output = new File(directory, name);
                if (!output.exists()) {
                    break;
                }
            }
            try {
                ImageIO.write(image, "png", output); // NOI18N
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
            written.put(icon, name);
        }
        return name;
    }


    /**
     * This method is from the The Java Developers Almanac 1.4
     * http://javaalmanac.com/egs/java.awt.image/Image2Buf.html
     * and is copyright by that book's author(s)
     */
    private static BufferedImage toBufferedImage(Image image) {
        // This method returns a buffered image with the contents of an image
        if (image instanceof BufferedImage) {
            return (BufferedImage)image;
        }
    
        // This code ensures that all the pixels in the image are loaded
        image = new ImageIcon(image).getImage();
    
        // Determine if the image has transparent pixels; for this method's
        // implementation, see e665 Determining If an Image Has Transparent Pixels
        //boolean hasAlpha = hasAlpha(image);
        boolean hasAlpha = true;
    
        // Create a buffered image with a format that's compatible with the screen
        BufferedImage bimage = null;
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        try {
            // Determine the type of transparency of the new buffered image
            int transparency = Transparency.OPAQUE;
            if (hasAlpha) {
                transparency = Transparency.BITMASK;
            }
    
            // Create the buffered image
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage(
                image.getWidth(null), image.getHeight(null), transparency);
        } catch (HeadlessException e) {
            // The system does not have a screen
        }
    
        if (bimage == null) {
            // Create a buffered image using the default color model
            int type = BufferedImage.TYPE_INT_RGB;
            if (hasAlpha) {
                type = BufferedImage.TYPE_INT_ARGB;
            }
            bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), type);
        }
    
        // Copy image to buffered image
        Graphics g = bimage.createGraphics();
    
        // Paint the image onto the buffered image
        g.drawImage(image, 0, 0, null);
        g.dispose();
    
        return bimage;
    }
    
}