package com.atlassian.core.util.thumbnail;
   
   import com.atlassian.core.util.ReusableBufferedInputStream;
   import com.google.common.base.Predicate;
   import org.apache.commons.io.IOUtils;
   import org.apache.log4j.Logger;
   
   import java.awt.image.BufferedImage;
   import java.io.IOException;
  import java.io.InputStream;
  
  public class ThumbnailRenderer
  {
  
      private final static Logger log = Logger.getLogger(ThumbnailRenderer.class);
  
      private final Predicate<Dimensions> rasterBasedRenderingThreshold;
      private final ImageScaler memoryImageScaler;
      private final ImageScaler streamImageScaler;
      private final DimensionsHelper dimensionsHelper;
  
      public ThumbnailRenderer(ImageScaler rasterScaler, ImageScaler streamScaler, DimensionsHelper dimensionsHelper, Predicate<Dimensions> rasterBasedRenderingThreshold)
      {
          this.rasterBasedRenderingThreshold = rasterBasedRenderingThreshold;
          this.memoryImageScaler = rasterScaler;
          this.streamImageScaler = streamScaler;
          this.dimensionsHelper = dimensionsHelper;
      }
  
      /**
       * Create a {@link BufferedImage} from the input stream.
       *
       * @param inputStream   - The stream that contains the image data
       * @param maxWidth      - The maximum width of the thumbnail - this renderer maintains the aspect ratio of the original image
       * @param maxHeight     - The maximum height of the thumbnail - this renderer maintains the aspect ratio of the original image
       * @return BufferedImage that is at most {@code maxWidth}x{@code maxHeight}, never returns null
       */
      public BufferedImage createThumbnailImage(final InputStream inputStream, final int maxWidth, final int maxHeight)
      {
          ReusableBufferedInputStream reusableInputStream = new ReusableBufferedInputStream(inputStream);
          try
          {
              final Dimensions originalImageDimensions = dimensionsHelper.dimensionsForImage(reusableInputStream);
              if (!rasterBasedRenderingThreshold.apply(originalImageDimensions))
              {
                  log.debug(String.format("Image dimensions (%s) exceed the threshold for raster based image manipulation. Using stream based renderer.", originalImageDimensions));
                  return streamImageScaler.scaleImage(maxWidth, maxHeight, reusableInputStream);
              }
              return memoryImageScaler.scaleImage(maxWidth, maxHeight, reusableInputStream);
          }
          catch (IOException e)
          {
              throw new ThumbnailRenderException(e);
          }
          finally
          {
              IOUtils.closeQuietly(inputStream);
              try
              {
                  reusableInputStream.destroy();
              }
              catch (IOException e)
              {
                  // Do nothing
              }
          }
      }
  }