package org.webslinger.ext.image;

 import java.awt.Rectangle;

 import java.io.File;

 import java.io.IOException;

 import org.apache.commons.vfs.FileObject;

 public abstract class AbstractSizingTransformerFactory implements ImageTransformerFactory {

     public Rectangle getKey(ImageDescriptor image) throws IOException {

         return getSize(image);

     }

     public boolean isEnabled(ImageDescriptor image) throws IOException {

         return true;

     }

     public ImageTransformer getTransformer(final ImageDescriptor image) throws IOException {

         final Rectangle size = getSize(image);

         if (size == null) {

             return new ImageTransformer() {

                 public boolean isEnabled() throws IOException {

                     return false;

                 }

                 public Rectangle transform(File file, Rectangle dimensions) throws InterruptedException, IOException {

                     throw new InternalError();

                 }

                 public String toString() {

                     return "";

                 }

             };

         }

         return new ImageTransformer() {

             public boolean isEnabled() throws IOException {

                 return true;

             }

             public Rectangle transform(File file, Rectangle dimensions) throws InterruptedException, IOException {

                 return AbstractSizingTransformerFactory.this.transform(image, file, size, dimensions);

             }

             public String toString() {

                 return "" + ((int) size.getWidth()) + '-' + ((int) size.getHeight());

             }

         };

     }

     public Rectangle transform(ImageDescriptor image, File file, Rectangle size, Rectangle dimensions) throws InterruptedException, IOException {

         return transform(image, file, (int) size.getWidth(), (int) size.getHeight());

     }

     protected abstract Rectangle transform(ImageDescriptor image, File file, int width, int height) throws InterruptedException, IOException;

     protected abstract Rectangle getSize(ImageDescriptor image) throws IOException;

 }