/***
    * Created on May 27, 2005, Copyright UC Regents
    */
   package org.telscenter.pas.steps;
   
   import java.util.logging.Level;
   import java.util.logging.Logger;
   
   import java.awt.Component;
  import java.awt.Container;
  import java.awt.Dimension;
  import java.awt.FlowLayout;
  import java.awt.Image;
  import java.awt.MediaTracker;
  import java.awt.Toolkit;
  import java.awt.datatransfer.DataFlavor;
  import java.awt.datatransfer.Transferable;
  import java.awt.datatransfer.UnsupportedFlavorException;
  import java.io.File;
  import java.io.IOException;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.net.URLConnection;
  import java.util.Iterator;
  import java.util.List;
  
  import javax.swing.ImageIcon;
  import javax.swing.JComponent;
  import javax.swing.JLabel;
  import javax.swing.JPanel;
  import javax.swing.TransferHandler;
  
  import org.telscenter.pas.beans.PasStep;
  
  
  /***
   * @author turadg
   */
  public class ImageCollector extends PasStep {
  	/***
  	 * Logger for this class
  	 */
  	private static final Logger logger = Logger.getLogger(ImageCollector.class
  			.getName());
  
  	JPanel panel;
  
  	static final int THUMBNAIL_MAX = 128;
  
  	public Component getComponent() {
  		if (panel != null)
  			return panel;
  
  		panel = new JPanel();
  		panel.setTransferHandler(new ImageFileTransferHandler());
  		panel.setLayout(new FlowLayout());
  
  		return panel;
  	}
  
  	Image thumbnailOf(Image original) {
  		// load original
  		MediaTracker mediaTracker = new MediaTracker(new Container());
  		mediaTracker.addImage(original, 0);
  		try {
  			mediaTracker.waitForID(0);
  		} catch (InterruptedException e) {
  			// TODO Auto-generated catch block
  			logger.severe("Image -  : exception: " + e); //$NON-NLS-1$
  		}
  
  		int originalWidth = original.getWidth(new Container());
  		int originalHeight = original.getHeight(new Container());
  
  		if (originalWidth <= THUMBNAIL_MAX && originalHeight <= THUMBNAIL_MAX) {
  			// no need to scale
  			return original;
  		}
  
  		// find new width and height
  		int thumbWidth;
  		int thumbHeight;
  		// which is bigger?
  		if (originalWidth > originalHeight) {
  			thumbWidth = THUMBNAIL_MAX;
  			thumbHeight = (int) (((float) thumbWidth / (float) originalWidth) * originalHeight);
  		} else {
  			thumbHeight = THUMBNAIL_MAX;
  			thumbWidth = (int) (((float) thumbHeight / (float) originalHeight) * originalWidth);
  		}
  
  		Image thumbImage = original.getScaledInstance(thumbWidth, thumbHeight,
  				Image.SCALE_SMOOTH);
  
  		return thumbImage;
  	}
  
  	void addImage(URL url) throws IOException {
  		if (logger.isLoggable(Level.CONFIG)) {
 			logger.config("adding image from url " + url); //$NON-NLS-1$
 		} 
 		URLConnection conn = url.openConnection();
 		String contentType = conn.getContentType();
 		if (contentType.startsWith("image/")) { //$NON-NLS-1$
 			Image image = (Image) conn.getContent(new Class[] { Image.class });
 			Image thumbnail = thumbnailOf(image);
 			ImageIcon imageIcon = new ImageIcon(thumbnail);
 			imageIcon.setDescription(url.toString());
 			JLabel label = new JLabel(imageIcon);
 			label.setMaximumSize(new Dimension(THUMBNAIL_MAX, THUMBNAIL_MAX));
 			panel.add(label);
 			panel.validate();
 		}
 	}
 
 	/***
 	 * derived from code at
 	 * http://www.java2s.com/ExampleCode/Swing-JFC/DroppershowFileDropTargetfromDragnDrop.htm
 	 * 
 	 * @author turadg
 	 */
 	class ImageFileTransferHandler extends TransferHandler {
 
 		public boolean canImport(JComponent comp, DataFlavor[] flavors) {
 			boolean canImport = false;
 			for (int i = 0; i < flavors.length; i++) {
 				DataFlavor flavor = flavors[i];
 				if (flavor.equals(DataFlavor.javaFileListFlavor))
 					canImport = true;
 				if (flavor.equals(DataFlavor.stringFlavor))
 					canImport = true;
 			}
 			return canImport;
 		}
 
 		@SuppressWarnings("unchecked")
 		public boolean importData(JComponent comp, Transferable t) {
 			DataFlavor[] flavors = t.getTransferDataFlavors();
 			logger.info("Trying to import:" + t); //$NON-NLS-1$
 			logger.info("... which has " + flavors.length + " flavors."); //$NON-NLS-1$ //$NON-NLS-2$
 			for (int i = 0; i < flavors.length; i++) {
 				DataFlavor flavor = flavors[i];
 				try {
 					if (flavor.equals(DataFlavor.javaFileListFlavor)) {
 						logger.info("importData: FileListFlavor"); //$NON-NLS-1$
 
 						List l = (List) t
 								.getTransferData(DataFlavor.javaFileListFlavor);
 						Iterator iter = l.iterator();
 						while (iter.hasNext()) {
 							File file = (File) iter.next();
 							logger.info("GOT FILE: " //$NON-NLS-1$
 									+ file.getCanonicalPath());
 							// Now do something with the file...
 							addImage(file.toURL());
 						}
 						return true;
 					} else if (flavor.equals(DataFlavor.stringFlavor)) {
 						logger.info("importData: String Flavor"); //$NON-NLS-1$
 						String fileOrURL = (String) t.getTransferData(flavor);
 						logger.info("GOT STRING: " + fileOrURL); //$NON-NLS-1$
 						try {
 							URL url = new URL(fileOrURL);
 							logger.info("Valid URL: " + url.toString()); //$NON-NLS-1$
 							// Do something with the contents...
 							addImage(url);
 							return true;
 						} catch (MalformedURLException ex) {
 							System.err.println("Not a valid URL"); //$NON-NLS-1$
 							return false;
 						}
 						// now do something with the String.
 
 					} else {
 						logger.info("importData rejected: " + flavor); //$NON-NLS-1$
 						// Don't return; try next flavor.
 					}
 				} catch (IOException ex) {
 					logger.warning("IOError getting data: " + ex); //$NON-NLS-1$
 				} catch (UnsupportedFlavorException e) {
 					logger.warning("Unsupported Flavor: " + e); //$NON-NLS-1$
 				}
 			}
 
 			// If you get here, I didn't like the flavor.
 			Toolkit.getDefaultToolkit().beep();
 			return false;
 		}
 	}
 
 }