/**
    * This file Copyright (c) 2015-2016 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.templating.imaging;
  
  import info.magnolia.imaging.ImagingException;
  import info.magnolia.imaging.OutputFormat;
  import info.magnolia.imaging.ParameterProvider;
  import info.magnolia.imaging.operations.ImageOperation;
  import info.magnolia.imaging.operations.ImageOperationChain;
  import info.magnolia.templating.imaging.parameters.ThemeAwareParameter;
  import info.magnolia.templating.imaging.variation.ImageOperationProvidingVariation;
  
  import java.awt.image.BufferedImage;
  import java.io.IOException;
  
  import javax.imageio.ImageIO;
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * {@link info.magnolia.imaging.ImageGenerator} that is aware of {@link info.magnolia.module.site.theme.Theme}s.
   */
  public class ThemeAwareImageGenerator extends ImageOperationChain<ParameterProvider<ThemeAwareParameter>> {
  
      private static final Logger log = LoggerFactory.getLogger(ThemeAwareImageGenerator.class);
  
      public static final String GENERATOR_NAME = "mte";
  
      @Override
      public BufferedImage generate(ParameterProvider<ThemeAwareParameter> parameters) throws ImagingException {
          final ThemeAwareParameter parameter = parameters.getParameter();
          return resolveImageVariation(parameter);
      }
  
      @Override
      public OutputFormat getOutputFormat(ParameterProvider<ThemeAwareParameter> parameters) {
          final ThemeAwareParameter parameter = parameters.getParameter();
  
          OutputFormat format;
          try {
              format = getOutputFormat().clone();
          } catch (CloneNotSupportedException e) {
              throw new RuntimeException("Can't clone the output format to produce a dynamic format.", e);
          }
  
          String extension = parameter.getExtension();
          format.setFormatName(extension);
  
          if ("gif".equals(StringUtils.lowerCase(extension))) {
              format.setCompressionType("lzw");
          } else {
              format.setCompressionType(null);
          }
  
          return format;
      }
  
      private BufferedImage resolveImageVariation(final ThemeAwareParameter parameter) throws ImagingException {
          final ImageOperationProvidingVariation variation = parameter.getImageVariation();
          if (variation == null) {
              try {
                  log.info("No image variation found, will return original image.");
                  return ImageIO.read(parameter.getBinary().getStream());
              } catch (IOException e) {
                 log.error("Error reading image from stream. Parameter was [{}].", parameter, e);
             } catch (RepositoryException e) {
                 log.error("Error reading image from stream. Parameter was [{}].", parameter, e);
             }
             return null;
         }
 
         final ImageOperation<ParameterProvider<Node>> imageOperation = variation.getImageOperation();
 
         return imageOperation.apply(null, new ParameterProvider<Node>() {
             @Override
             public Node getParameter() {
                 return parameter.getNode();
             }
         });
     }
 }