content: /*
   * This library is part of OpenCms -
   * the Open Source Content Management System
   *
   * Copyright (c) Alkacon Software GmbH & Co. KG (https://www.alkacon.com)
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * For further information about Alkacon Software, please see the
   * company website: https://www.alkacon.com
   *
   * For further information about OpenCms, please see the
   * project website: https://www.opencms.org
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.opencms.pdftools;
  
  import org.opencms.file.CmsFile;
  import org.opencms.file.CmsObject;
  import org.opencms.loader.CmsImageScaler;
  import org.opencms.main.CmsException;
  import org.opencms.main.CmsLog;
  import org.opencms.main.OpenCms;
  
  import java.io.ByteArrayInputStream;
  import java.net.URI;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.apache.commons.logging.Log;
  
  import org.xhtmlrenderer.extend.FSImage;
  import org.xhtmlrenderer.layout.SharedContext;
  import org.xhtmlrenderer.pdf.ITextFSImage;
  import org.xhtmlrenderer.resource.CSSResource;
  import org.xhtmlrenderer.resource.ImageResource;
  import org.xhtmlrenderer.swing.NaiveUserAgent;
  
  import com.lowagie.text.Image;
  
  /**
   * This class is responsible for loading external resources while generating PDF from XHTML.
   *
   * Resources will be loaded from the VFS. Additionally, if there are image scaler parameters in  an image
   * URI, the scaled image data will be returned. Please note that this class just reads the data from the linked
   * resources; it will not go through OpenCms's resource loaders, so you can't e.g. use a JSP as a dynamic stylesheet.
   */
  public class CmsPdfUserAgent extends NaiveUserAgent {
  
      /** The regex to match image scaler parameters. */
      public static final Pattern SCALE_PARAMS_PATTERN = Pattern.compile("__scale=(.*?)(?:&|$)");
  
      /** The image cache capacity. */
      private static final int IMAGE_CACHE_CAPACITY = 64;
  
      /** The logger instance for this class. */
      private static final Log LOG = CmsLog.getLog(CmsPdfUserAgent.class);
  
      /** The CMS context to use for loading the resources. */
      private CmsObject m_cms;
  
      /** The CMS context to use, with the site root set to the root site. */
      private CmsObject m_rootCms;
  
      /** The shared context. */
      private SharedContext m_sharedContext;
  
      /**
       * Creates a new instance.<p>
       *
       * @param cms the CMS context
       *
       * @throws CmsException if something goes wrong
       */
      public CmsPdfUserAgent(CmsObject cms)
      throws CmsException {
  
          super(IMAGE_CACHE_CAPACITY);
  
          m_cms = cms;
          m_rootCms = OpenCms.initCmsObject(cms);
          m_rootCms.getRequestContext().setSiteRoot("");
      }
  
      /**
       * @see org.xhtmlrenderer.swing.NaiveUserAgent#getBinaryResource(java.lang.String)
       */
      @Override
      public byte[] getBinaryResource(String uri) {
  
          return readFile(uri);
      }
  
      /**
       * @see org.xhtmlrenderer.swing.NaiveUserAgent#getCSSResource(java.lang.String)
       */
      @Override
      public CSSResource getCSSResource(String uri) {
  
          return new CSSResource(getStream(readFile(uri)));
      }
  
      /**
       * @see org.xhtmlrenderer.swing.NaiveUserAgent#getImageResource(java.lang.String)
       */
      @SuppressWarnings("unchecked")
      @Override
      public ImageResource getImageResource(String uri) {
  
          ImageResource resource = null;
          resource = (ImageResource)_imageCache.get(uri);
          if (resource == null) {
              byte[] imageData = readImage(uri);
              if (imageData != null) {
                  try {
                      Image image = Image.getInstance(imageData);
                      scaleToOutputResolution(image);
                      resource = new ImageResource(uri, new ITextFSImage(image));
                      _imageCache.put(uri, resource);
                  } catch (Exception e) {
                      LOG.error("Problem with getting image resource " + uri, e);
                  }
              }
          }
  
          if (resource != null) {
              resource = new ImageResource(resource.getImageUri(), (FSImage)((ITextFSImage)resource.getImage()).clone());
          } else {
              resource = new ImageResource(uri, null);
          }
          return resource;
      }
  
      /**
       * Gets the shared context.<p>
       *
       * @return the shared context
       */
      public SharedContext getSharedContext() {
  
          return m_sharedContext;
      }
  
      /**
       * @see org.xhtmlrenderer.swing.NaiveUserAgent#resolveURI(java.lang.String)
       */
      @Override
      public String resolveURI(String uri) {
  
          // we want to pass the uri unchanged to the get... methods
          return uri;
      }
  
      /**
       * Sets the shared context.<p>
       *
       * @param sharedContext the shared context
       */
      public void setSharedContext(SharedContext sharedContext) {
  
          m_sharedContext = sharedContext;
      }
  
      /**
       * Converts a byte array to an input stream, but returns null if the byte array is null.<p>
       *
       * @param data the data
       * @return the input stream for the data, or null
       */
      ByteArrayInputStream getStream(byte[] data) {
  
          if (data == null) {
              return null;
          } else {
              return new ByteArrayInputStream(data);
          }
      }
  
      /**
       * Reads a file from the VFS.<p>
       *
       * @param uriWithParams the
       * @return the file data
       */
      private byte[] readFile(String uriWithParams) {
  
          try {
              String pathAndQuery = OpenCms.getLinkManager().getRootPath(m_cms, uriWithParams);
              URI uri = new URI(pathAndQuery);
              String path = uri.getPath();
              CmsFile file = m_rootCms.readFile(path);
              return file.getContents();
          } catch (Exception e) {
              LOG.error("Problem with reading CSS " + uriWithParams + ": " + e.getLocalizedMessage(), e);
              return null;
          }
      }
  
      /**
       * Reads an image from the VFS, scaling it if necessary.<p>
       *
       * @param uriWithParams the image uri, possible with scaling parameter
       *
       * @return the image data
       */
      private byte[] readImage(String uriWithParams) {
  
          try {
              String pathAndQuery = OpenCms.getLinkManager().getRootPath(m_cms, uriWithParams);
              URI uri = new URI(pathAndQuery);
              String path = uri.getPath();
              String query = uri.getQuery();
              String scaleParams = null;
              if (query != null) {
                  Matcher matcher = SCALE_PARAMS_PATTERN.matcher(query);
                  if (matcher.find()) {
                      scaleParams = matcher.group(1);
                  }
              }
              CmsFile imageFile = m_rootCms.readFile(path);
              byte[] result = imageFile.getContents();
              if (scaleParams != null) {
                  CmsImageScaler scaler = new CmsImageScaler(scaleParams);
                  result = scaler.scaleImage(imageFile);
              }
              return result;
          } catch (Exception e) {
              LOG.error("Problem with reading image " + uriWithParams + ": " + e.getLocalizedMessage(), e);
              return null;
          }
      }
  
      /**
       * Scales the image to output resolution.<p>
       *
       * @param image the image to scale
       */
      private void scaleToOutputResolution(Image image) {
  
          float factor = m_sharedContext.getDotsPerPixel();
          if (factor != 1.0f) {
              image.scaleAbsolute(image.getPlainWidth() * factor, image.getPlainHeight() * factor);
          }
      }
  
  }
  