/*

  * Copyright (c) 2003-2011, Simon Brown

  * All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions are met:

  *

  *   - Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  *

  *   - Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in

  *     the documentation and/or other materials provided with the

  *     distribution.

  *

  *   - Neither the name of Pebble nor the names of its contributors may

  *     be used to endorse or promote products derived from this software

  *     without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

  * POSSIBILITY OF SUCH DAMAGE.

  */

 package net.sourceforge.pebble.web.listener;

 import org.xhtmlrenderer.pdf.ITextRenderer;

 import org.xhtmlrenderer.pdf.PDFCreationListener;

 import java.util.Properties;

 import java.util.Enumeration;

 import org.w3c.dom.Document;

 import org.w3c.dom.Element;

 import org.w3c.dom.Node;

 import org.w3c.dom.NodeList;

 import com.lowagie.text.pdf.PdfName;

 import com.lowagie.text.pdf.PdfString;

 import com.lowagie.text.pdf.PdfObject;

 import com.lowagie.text.pdf.PdfWriter;

 import com.lowagie.text.pdf.PdfDictionary;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 /**

  * Add ability to manipulate PDF output document before it's closed and opened.

  *  

  * Soltuion was adopted from: https://xhtmlrenderer.dev.java.net/servlets/ReadMsg?listName=users&msgNo=1908

  *

  * @author    Alexander Zagniotov

  */

 public class PebblePDFCreationListener implements PDFCreationListener {

         /** the log used by this class */

         private static Log log = LogFactory.getLog(PebblePDFCreationListener.class);

         Properties headerTags = null;

         public PebblePDFCreationListener()  {

                 headerTags = new Properties();

         }

         public void parseMetaTags(Document sourceXHTML) {

                 try {

                         NodeList e = sourceXHTML.getDocumentElement().getElementsByTagName("head");

                         Element e1 = (Element) e.item(0);

                         NodeList retVal = e1.getElementsByTagName("meta");

                         for (int i = 0; i < retVal.getLength(); i++) {

                                         Element thisNode = (Element) retVal.item(i);

                                         String name = thisNode.getAttribute("name");

                                         String content = thisNode.getAttribute("content");

                                         //<meta name="XXXXX" content="XXXXX" />

                                         if (name.length() != 0 && content.length() != 0) {

                                                 headerTags.setProperty(name,content);

                                         }

                                 }

                 }

                 catch (Exception e)  {

                                 log.warn("Could not parse header meta tags: " + e);

                 }

      }

     /**

          * Called directly before calling open() on the Document. 

          * That allows you to e.g. modify headers before the document is created.

          *

          */

         public void preOpen(ITextRenderer renderer) { 

                 try {

                         Enumeration e = headerTags.propertyNames();

                         PdfWriter writer = renderer.getWriter(); 

                          if (writer == null) {

                                          log.warn("PdfWriter is null, not able to set header meta tags to PDF document");

                                          return;

                          }

                          /*

                                         Available versions:

                                         PdfWriter.VERSION_1_2,

                                         PdfWriter.VERSION_1_3,

                                         PdfWriter.VERSION_1_4,  //default

                                         PdfWriter.VERSION_1_5,

                                         PdfWriter.VERSION_1_6,

                                         PdfWriter.VERSION_1_7

                                 */

                         writer.setPdfVersion(PdfWriter.VERSION_1_5);

                         //Full compression means that not only page streams are compressed, 

                         //but some other objects as well, such as the cross-reference table. 

                         //This is only possible since PDF-1.5

                         writer.setFullCompression();

                         while (e.hasMoreElements())  { 

                                   String key = (String) e.nextElement() ;

                                   PdfString val = new PdfString(headerTags.getProperty(key), PdfObject.TEXT_UNICODE);

                                   PdfDictionary dictionary = writer.getInfo();

                                   if (key.equals("title" )) {

                                                 dictionary.put(PdfName.TITLE, val);

                                   }

                                   else if (key.equals("author")) {

                                                 dictionary.put(PdfName.AUTHOR, val);  

                                   }

                                   else if (key.equals("subject")) {

                                                 dictionary.put(PdfName.SUBJECT, val);  

                                   }

                                   else if (key.equals("keywords")) {

                                                 dictionary.put(PdfName.KEYWORDS, val);  

                                   }

                                   else if (key.equals("creator")) {

                                                 dictionary.put(PdfName.CREATOR, val);  

                                   }

                                   else if (key.equals("producer")) {

                                                 dictionary.put(PdfName.PRODUCER, val);  

                                   }

                                   else  {

                                                 log.warn("Unexpected header meta tag: " + key + ", value: " + val);

                                   }

                                 }

                         }

                         catch (Exception e)  {

                                 log.warn("Could not set header meta tags to PDF document: " + e);

                         }

         }

     public void onClose(ITextRenderer renderer) { 

                 PdfWriter writer = renderer.getWriter(); 

                 if (writer == null) {

                          log.warn("PdfWriter is null, not able to set header meta tags to PDF document");

                          return;

                 }

                 //Display doc title in the title bar instead of filename,

                 writer.setViewerPreferences(PdfWriter.DisplayDocTitle);

         }

 }