/**
    * This file Copyright (c) 2014-2018 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.ui.framework.action;
  
  import com.vaadin.util.EncodeUtil;
  import info.magnolia.ui.api.action.AbstractAction;
  import info.magnolia.ui.api.action.ActionExecutionException;
  import info.magnolia.ui.vaadin.integration.jcr.JcrItemAdapter;
  import info.magnolia.ui.vaadin.integration.jcr.JcrNodeAdapter;
  import info.magnolia.ui.vaadin.server.DownloadStreamResource;
  
  import java.io.InputStream;
  
  import javax.inject.Inject;
  import javax.jcr.Binary;
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  
  import com.vaadin.server.Page;
  import com.vaadin.server.StreamResource;
  
  /**
   * Action for downloading a binary.
   *
   * @param <D> action definition
   */
  public class DownloadBinaryAction<D extends DownloadBinaryActionDefinition> extends AbstractAction<D> {
  
      private static final String CONTENT_TYPE = "application/octet-stream";
      private final DownloadBinaryActionDefinition definition;
      private final JcrItemAdapter item;
  
      @Inject
      public DownloadBinaryAction(D definition, JcrItemAdapter item) {
          super(definition);
          this.definition = definition;
          this.item = item;
      }
  
      @Override
      public void execute() throws ActionExecutionException {
          if (item instanceof JcrNodeAdapter) {
              final Node node = (Node) item.getJcrItem();
              final InputStream inputStream;
              Node binaryNode;
              String fileName;
              StreamResource streamResource;
              try {
                  binaryNode = getBinaryNode(node);
                  fileName = getFileName(binaryNode);
                  inputStream = getInputStream(binaryNode);
                  streamResource = getStreamResource(inputStream, fileName);
  
                  Page.getCurrent().open(streamResource, null, false);
              } catch (RepositoryException e) {
                  throw new ActionExecutionException(String.format("Error getting binary data from node [%s] to download.", node), e);
              }
          }
      }
  
      /**
       * Returns a downloadable {@link DownloadStreamResource} created from the supplied {@link InputStream}.
       *
       * @see com.vaadin.server.DownloadStream#DEFAULT_CACHETIME
       * @see StreamResource
       */
      protected DownloadStreamResource getStreamResource(final InputStream inputStream, String fileName) {
          final DownloadStreamResource resource = new DownloadStreamResource(new StreamResource.StreamSource() {
             @Override
             public InputStream getStream() {
                 return inputStream;
             }
         }, fileName);
         // Accessing the DownloadStream via getStream() will set its cacheTime to whatever is set in the parent
         // StreamResource. By default it is set to 1000 * 60 * 60 * 24, thus we have to override it beforehand.
         // A negative value or zero will disable caching of this stream.
         resource.setCacheTime(-1);
         String encodedFilename = EncodeUtil.rfc5987Encode(fileName);
         resource.getStream().setParameter("Content-Disposition", String.format("attachment;filename=\"%s\"; filename*=utf-8''%s",
                 encodedFilename, encodedFilename));
         resource.setMIMEType(CONTENT_TYPE);
         return resource;
     }
 
     protected InputStream getInputStream(Node binaryNode) throws RepositoryException {
         Binary binary = binaryNode.getProperty(definition.getDataProperty()).getBinary();
         return binary.getStream();
     }
 
     protected String getFileName(Node binaryNode) throws RepositoryException {
         String fileName = binaryNode.getProperty(definition.getFileNameProperty()).getString();
         String extension = "." + binaryNode.getProperty(definition.getExtensionProperty()).getString();
         return fileName.endsWith(extension) ? fileName : fileName + extension;
     }
 
     protected Node getBinaryNode(Node node) throws RepositoryException {
         return node.getNode(definition.getBinaryNodeName());
     }
 
 }