/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/



package graphical;

import java.awt.Image;
import java.awt.image.PixelGrabber;
import java.awt.image.ImageObserver;
import java.io.File;
//import javax.imageio.ImageIO;
import java.lang.reflect.Method;

class ImageHelper
{
    Image m_aImage;
    int[] m_aPixels;
    int m_w = 0;
    int m_h = 0;
    boolean m_bGrabbed = false;
    
    private ImageHelper(Image _aImage)
    {
         m_aImage = _aImage;

         // grab all (consume much memory)
         m_w = getWidth();
         m_h = getHeight();
		 int x = 0;
		 int y = 0;
         m_aPixels = new int[m_w * m_h];
         PixelGrabber pg = new PixelGrabber(m_aImage, x, y, m_w, m_h, m_aPixels, 0, m_w);
         try
         {
             pg.grabPixels();
         }
         catch (InterruptedException e)
         {
             System.err.println("interrupted waiting for pixels!");
             return;
         }
         if ((pg.getStatus() & ImageObserver.ABORT) != 0)
         {
             System.err.println("image fetch aborted or errored");
             return;
         }
         m_bGrabbed = true;
    }
    public int getWidth() {return m_aImage.getWidth(null);}
    public int getHeight() {return m_aImage.getHeight(null);}
    // direct access to a pixel
    public int getPixel(final int x, final int y)
        {
            return m_aPixels[y * m_w + x];
        }

    // Write down the current image to a file.
    // public void storeImage(String _sFilename)
    //    { 
    //    }

    public static ImageHelper createImageHelper(String _sFilename)
        throws java.io.IOException
        {
            Image aImage = null;
            File aFile = new File(_sFilename);
            Exception ex = null;
            try {
                Class imageIOClass = Class.forName("javax.imageio.ImageIO");
                Method readMethod = imageIOClass.getDeclaredMethod("read", new Class[]{java.io.File.class});
                Object retValue = readMethod.invoke(imageIOClass, new Object[]{aFile});
                aImage = (Image)retValue;
            }
            catch(java.lang.ClassNotFoundException e) {
                ex = e;
            }
            catch(java.lang.NoSuchMethodException e) {
                ex = e;
            }
            catch(java.lang.IllegalAccessException e) {
                ex = e;
            }
            catch(java.lang.reflect.InvocationTargetException e) {
                ex = e;
            }

            if (ex != null) {
                // get Java version:
                String javaVersion = System.getProperty("java.version");
                throw new java.io.IOException(
                    "Cannot construct object with current Java version " +
                    javaVersion + ": " + ex.getMessage());
            }
//            aImage = ImageIO.read(aFile);            
            return new ImageHelper(aImage);
        }
}