/*

  * 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.filter;

 import net.sourceforge.pebble.Constants;

 import net.sourceforge.pebble.domain.AbstractBlog;

 import net.sourceforge.pebble.domain.Blog;

 import net.sourceforge.pebble.domain.BlogManager;

 import net.sourceforge.pebble.domain.MultiBlog;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import javax.servlet.*;

 import javax.servlet.http.HttpServletRequest;

 import java.io.IOException;

 import java.net.URLDecoder;

 /**

  * A filter that transforms an incoming URI into an action URI.

  *

  * @author    Simon Brown

  */

 public class TransformingFilter implements Filter {

   /** the config of this filter */

   private FilterConfig filterConfig;

   /** the log used by this class */

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

   /**

    * Initialises this instance.

    *

    * @param config    a FilterConfig instance

    */

   public void init(FilterConfig config) {

     this.filterConfig = config;

   }

   /**

    * Called when this filter is taken out of service.

    */

   public void destroy() {

   }

   /**

    * Contains the processing associated with this filter.

    */

   public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

       throws ServletException, IOException {

     HttpServletRequest httpRequest = (HttpServletRequest)request;

     AbstractBlog blog = (AbstractBlog)request.getAttribute(Constants.BLOG_KEY);

     String originalUri = httpRequest.getRequestURI();

     // get URI and strip off the context (e.g. /blog)

     String uri = originalUri.substring(httpRequest.getContextPath().length(), originalUri.length());

     // now we're left with a URI

     if (BlogManager.getInstance().isMultiBlog()) {

       if (uri.length() == 0) {

         uri = "/";

       }

       int index = uri.indexOf("/", 1);

       if (index == -1) {

         index = uri.length();

       }

       String blogName = uri.substring(1, index);

       blogName = URLDecoder.decode(blogName, "UTF-8");

       if (BlogManager.getInstance().hasBlog(blogName)) {

         uri = uri.substring(index, uri.length());

       }

     }

     if (uri == null || uri.trim().equals("")) {

       uri = "/";

     }

     log.trace("uri : " + uri);

     // Only add the query string to external URI, otherwise each parameter in the query string will end up being put in

     // twice to the parameter map.

     String externalUri = uri;

     if (httpRequest.getQueryString() != null) {

       externalUri += "?" + httpRequest.getQueryString();

       originalUri += "?" + httpRequest.getQueryString();

     }

     httpRequest.setAttribute(Constants.ORIGINAL_URI, originalUri);

     httpRequest.setAttribute(Constants.EXTERNAL_URI, externalUri);

     UriTransformer transformer = new UriTransformer();

     String internalUri;

     if (blog instanceof Blog) {

       internalUri = transformer.getUri(uri, (Blog)blog);

     } else {

       internalUri = transformer.getUri(uri, (MultiBlog)blog);

     }

     request.setAttribute(Constants.INTERNAL_URI, internalUri);

     log.trace(uri + " -> " + internalUri);

     chain.doFilter(request, response);

   }

 }