/**
    * This file Copyright (c) 2003-2018 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.cms.filters;
  
  import info.magnolia.cms.beans.config.URI2RepositoryManager;
  import info.magnolia.cms.beans.config.URI2RepositoryMapping;
  import info.magnolia.cms.core.AggregationState;
  import info.magnolia.cms.util.SelectorUtil;
  import info.magnolia.context.MgnlContext;
  
  import java.io.IOException;
  
  import javax.inject.Inject;
  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 org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Maps a URI to content stored in the repository. Determine the workspace name
   * and content path.
   *
   * @see URI2RepositoryMapping
   * @see URI2RepositoryManager
   */
  public class RepositoryMappingFilter extends AbstractMgnlFilter {
      private static final Logger log = LoggerFactory.getLogger(RepositoryMappingFilter.class);
  
      private URI2RepositoryManager uri2RepositoryManager;
  
      @Inject
      public RepositoryMappingFilter(URI2RepositoryManager uri2RepositoryManager) {
          this.uri2RepositoryManager = uri2RepositoryManager;
      }
  
      @Override
      public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
          String uri = MgnlContext.getAggregationState().getCurrentURI();
          int firstSelectorDelimiterPos = StringUtils.indexOf(uri, SelectorUtil.SELECTOR_DELIMITER, StringUtils.lastIndexOf(uri, '/'));
          String path;
          // TODO Warning - this might change in the future - see MAGNOLIA-2343 for details.
          String selector;
          if (firstSelectorDelimiterPos > -1) {
              int lastSelectorDelimiterPos = StringUtils.lastIndexOf(uri, SelectorUtil.SELECTOR_DELIMITER);
              path = StringUtils.substring(uri, 0, firstSelectorDelimiterPos);
              selector = StringUtils.substring(uri, firstSelectorDelimiterPos + 1, lastSelectorDelimiterPos);
          } else {
              // no tilde (and no extension)
              path = uri;
              selector = "";
          }
  
          URI2RepositoryMapping mapping = uri2RepositoryManager.getMapping(uri);
  
          // remove prefix if any
          path = mapping.getHandle(path);
  
          final AggregationState aggregationState = MgnlContext.getAggregationState();
          aggregationState.setRepository(mapping.getRepository());
          aggregationState.setHandle(path);
  
          // selector could potentially be set from some other place, but we have no better idea for now :)
          try {
              aggregationState.setSelector(selector);
         } catch (IllegalArgumentException e) {
             // Selector which is part of an URI is malformed and cannot be decoded - send back error 400
             if (!response.isCommitted()) {
                 response.sendError(HttpServletResponse.SC_BAD_REQUEST, "URL is malformed (not encoded properly).");
             }
             // stop filter chain
             return;
         }
         chain.doFilter(request, response);
     }
 }