/**
    * This file Copyright (c) 2003-2015 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.cms.filters;
  
  import info.magnolia.cms.beans.runtime.Document;
  import info.magnolia.cms.beans.runtime.MultipartForm;
  import info.magnolia.cms.core.Path;
  import info.magnolia.context.MgnlContext;
  
  import java.io.IOException;
  import java.util.Enumeration;
  import java.util.Iterator;
  
  import javax.servlet.FilterChain;
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.lang3.StringUtils;
  
  import com.oreilly.servlet.MultipartRequest;
  
  /**
   * Processes multipart post requests (fileuploads). Files can be accessed with {@link MultipartForm#getDocument(String)}.
   */
  public class CosMultipartRequestFilter extends OncePerRequestAbstractMgnlFilter {
  
      /**
       * Max file upload size.
       */
      private static final int MAX_FILE_SIZE = 2000000000; // 2GB
  
      @Override
      public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
              throws IOException, ServletException {
  
          String type = null;
          String type1 = request.getHeader("Content-Type");
          String type2 = request.getContentType();
          if (type1 == null && type2 != null) {
              type = type2;
          } else if (type2 == null && type1 != null) {
              type = type1;
          } else if (type1 != null) {
              type = (type1.length() > type2.length() ? type1 : type2);
          }
          boolean isMultipart = (type != null) && type.toLowerCase().startsWith("multipart/form-data");
          MultipartForm mpf = null;
          try {
              if (isMultipart) {
                  mpf = parseParameters(request);
                  request = new MultipartRequestWrapper(request, mpf);
                  MgnlContext.push(request, response);
              }
              try {
                  chain.doFilter(request, response);
              } finally {
                  if (isMultipart) {
                      MgnlContext.pop();
                  }
              }
          } finally {
              if (mpf != null) {
                  Iterator<Document> keys = mpf.getDocuments().values().iterator();
                  while (keys.hasNext()) {
                      Document doc = keys.next();
                      if (doc != null && doc.getFile() != null && doc.getFile().exists()) {
                          doc.delete();
                     }
                 }
             }
         }
     }
 
     /**
      * Adds all request paramaters as request attributes.
      *
      * @param request HttpServletRequest
      */
     private static MultipartForm parseParameters(HttpServletRequest request) throws IOException {
         MultipartForm form = new MultipartForm();
         String encoding = StringUtils.defaultString(request.getCharacterEncoding(), "UTF-8");
         MultipartRequest multi = new MultipartRequest(
                 request,
                 Path.getTempDirectoryPath(),
                 MAX_FILE_SIZE,
                 encoding,
                 null);
         Enumeration params = multi.getParameterNames();
         while (params.hasMoreElements()) {
             String name = (String) params.nextElement();
             String value = multi.getParameter(name);
             form.addParameter(name, value);
             String[] s = multi.getParameterValues(name);
             if (s != null) {
                 form.addparameterValues(name, s);
             }
         }
         Enumeration files = multi.getFileNames();
         while (files.hasMoreElements()) {
             String name = (String) files.nextElement();
             form.addDocument(name, multi.getFilesystemName(name), multi.getContentType(name), multi.getFile(name));
         }
         request.setAttribute(MultipartForm.REQUEST_ATTRIBUTE_NAME, form);
         return form;
     }
 }