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 GmbH & Co. KG, 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.loader;
  
  import org.opencms.configuration.CmsParameterConfiguration;
  import org.opencms.file.CmsObject;
  import org.opencms.file.CmsResource;
  import org.opencms.i18n.CmsEncoder;
  import org.opencms.i18n.CmsLocaleManager;
  import org.opencms.main.CmsException;
  import org.opencms.main.CmsLog;
  import org.opencms.main.CmsRuntimeException;
  import org.opencms.main.OpenCms;
  import org.opencms.util.CmsRequestUtil;
  import org.opencms.util.CmsStringUtil;
  
  import java.io.IOException;
  import java.util.Locale;
  import java.util.Map;
  
  import javax.servlet.ServletRequest;
  import javax.servlet.ServletResponse;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  /**
   * Loader for "pointers" to resources in the VFS or to external resources.<p>
   *
   * @since 6.0.0
   */
  public class CmsPointerLoader extends CmsDumpLoader {
  
      /**
       * The configuration parameter for the OpenCms XML configuration to enable
       * that the parameters in requests to pointer resources are appended to the
       * pointer target link.
       */
      public static final String CONFIGURATION_REQUEST_PARAM_SUPPORT_ENABLED = "pointer.requestparamsupport.enabled";
  
      /** The id of this loader. */
      public static final int RESOURCE_POINTER_LOADER_ID = 4;
  
      /**
       * Flag that controls if parameters in requests to pointer resources are
       * appended to the target link when redirecting.
       */
      protected static boolean m_requestParamSupportEnabled;
  
      /** The html-code prefix for generating the export file for external links. */
      private static String EXPORT_PREFIX = "<html>\n<head>\n<meta http-equiv="
          + '"'
          + "refresh"
          + '"'
          + " content="
          + '"'
          + "0; url=";
  
      /** The html-code suffix for generating the export file for external links. */
      private static String EXPORT_SUFFIX = '"' + ">\n</head>\n<body></body>\n</html>";
  
      /**
       * The constructor of the class is empty and does nothing.<p>
       */
      public CmsPointerLoader() {
  
          // NOOP
      }
  
      /**
       * Returns <code>true</code> if parameters in requests to pointer resources
       * are appended to the target link when redirecting.
       * <p>
       * This is controlled by the configuration of this loader in
       * <code>opencms-system.xml</code>.
       * <p>
       *
       * @return <code>true</code> if parameters in requests to pointer resources
       *         are appended to the target link when redirecting.
       */
      public static boolean isRequestParamSupportEnabled() {
  
          return m_requestParamSupportEnabled;
      }
  
      /**
       * Internal helper that is used by
       * <code>{@link #load(CmsObject, CmsResource, HttpServletRequest, HttpServletResponse)}</code>
       * and
       * <code>{@link #export(CmsObject, CmsResource, HttpServletRequest, HttpServletResponse)}</code>
       * to handle conditional request parameter support for links to pointer
       * resources.
       * <p>
       *
       * @param pointerLink
       *            the link to append request parameters to
       *
       * @param req
       *            the original request to the pointer
       *
       * @return the pointer with the parameters
       */
      private static String appendLinkParams(String pointerLink, HttpServletRequest req) {
  
          String result = pointerLink;
          if (isRequestParamSupportEnabled()) {
              Map<String, String[]> params = req.getParameterMap();
              if (params.size() > 0) {
                  result = CmsRequestUtil.appendParameters(result, params, false);
              }
          }
          return result;
      }
  
      /**
       * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#addConfigurationParameter(java.lang.String, java.lang.String)
       */
      @Override
      public void addConfigurationParameter(String paramName, String paramValue) {
  
          if (CmsStringUtil.isNotEmpty(paramName) && CmsStringUtil.isNotEmpty(paramValue)) {
              if (CONFIGURATION_REQUEST_PARAM_SUPPORT_ENABLED.equals(paramName)) {
                  m_requestParamSupportEnabled = Boolean.valueOf(paramValue).booleanValue();
              }
          }
      }
  
      /**
       * Destroy this ResourceLoder, this is a NOOP so far.<p>
       */
      @Override
      public void destroy() {
  
          // NOOP
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#dump(org.opencms.file.CmsObject, org.opencms.file.CmsResource, java.lang.String, java.util.Locale, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
       */
      @Override
      public byte[] dump(
          CmsObject cms,
          CmsResource resource,
          String element,
          Locale locale,
          HttpServletRequest req,
          HttpServletResponse res) throws CmsException {
  
          return cms.readFile(resource).getContents();
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#export(org.opencms.file.CmsObject, org.opencms.file.CmsResource, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
       */
      @Override
      public byte[] export(CmsObject cms, CmsResource resource, HttpServletRequest req, HttpServletResponse res)
      throws IOException, CmsException {
  
          String pointer = new String(
              cms.readFile(resource).getContents(),
              CmsLocaleManager.getResourceEncoding(cms, resource));
          StringBuffer result = new StringBuffer(128);
          result.append(EXPORT_PREFIX);
          // conditionally append parameters of the current request:
          pointer = appendLinkParams(pointer, req);
          if (pointer.indexOf(':') < 0) {
              result.append(OpenCms.getLinkManager().substituteLink(cms, pointer));
          } else {
              result.append(pointer);
          }
          result.append(EXPORT_SUFFIX);
          load(cms, resource, req, res);
          return result.toString().getBytes(OpenCms.getSystemInfo().getDefaultEncoding());
      }
  
      /**
       * Will always return <code>null</code> since this loader does not
       * need to be cnofigured.<p>
       *
       * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#getConfiguration()
       */
      @Override
      public CmsParameterConfiguration getConfiguration() {
  
          CmsParameterConfiguration result = new CmsParameterConfiguration();
          CmsParameterConfiguration config = super.getConfiguration();
          if (config != null) {
              result.putAll(config);
          }
          result.put(CONFIGURATION_REQUEST_PARAM_SUPPORT_ENABLED, String.valueOf(m_requestParamSupportEnabled));
          return result;
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#getLoaderId()
       */
      @Override
      public int getLoaderId() {
  
          return RESOURCE_POINTER_LOADER_ID;
      }
  
      /**
       * Return a String describing the ResourceLoader,
       * which is (localized to the system default locale)
       * <code>"The OpenCms default resource loader for pointers"</code>.<p>
       *
       * @return a describing String for the ResourceLoader
       */
      @Override
      public String getResourceLoaderInfo() {
  
          return Messages.get().getBundle().key(Messages.GUI_LOADER_POINTER_DEFAULT_DESC_0);
      }
  
      /**
       * @see org.opencms.configuration.I_CmsConfigurationParameterHandler#initConfiguration()
       */
      @Override
      public void initConfiguration() {
  
          if (CmsLog.INIT.isInfoEnabled()) {
              CmsLog.INIT.info(
                  Messages.get().getBundle().key(Messages.INIT_LOADER_INITIALIZED_1, this.getClass().getName()));
          }
      }
  
      /**
       * Returns true if request parameter support is disabled. <p>
       *
       * @return
       *      true if request parameter support is disabled
       *
       * @see org.opencms.loader.I_CmsResourceLoader#isStaticExportEnabled()
       */
      @Override
      public boolean isStaticExportEnabled() {
  
          return !m_requestParamSupportEnabled;
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#isStaticExportProcessable()
       */
      @Override
      public boolean isStaticExportProcessable() {
  
          return false;
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#isUsableForTemplates()
       */
      @Override
      public boolean isUsableForTemplates() {
  
          return false;
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#isUsingUriWhenLoadingTemplate()
       */
      @Override
      public boolean isUsingUriWhenLoadingTemplate() {
  
          return false;
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#load(org.opencms.file.CmsObject, org.opencms.file.CmsResource, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
       */
      @Override
      public void load(CmsObject cms, CmsResource resource, HttpServletRequest req, HttpServletResponse res)
      throws IOException, CmsException {
  
          if ((res == null) || res.isCommitted()) {
              // nothing we can do
              return;
          }
  
          String pointer = new String(
              cms.readFile(resource).getContents(),
              CmsLocaleManager.getResourceEncoding(cms, resource));
          if (CmsStringUtil.isEmptyOrWhitespaceOnly(pointer)) {
              throw new CmsLoaderException(
                  Messages.get().container(Messages.ERR_INVALID_POINTER_FILE_1, resource.getName()));
          }
          if (pointer.indexOf(':') < 0) {
              pointer = OpenCms.getLinkManager().substituteLink(cms, pointer);
          } else {
              pointer = CmsEncoder.convertHostToPunycode(pointer);
          }
  
          // conditionally append parameters of the current request:
          pointer = appendLinkParams(pointer, req);
  
          res.sendRedirect(pointer);
      }
  
      /**
       * @see org.opencms.loader.I_CmsResourceLoader#service(org.opencms.file.CmsObject, org.opencms.file.CmsResource, javax.servlet.ServletRequest, javax.servlet.ServletResponse)
       */
      @Override
      public void service(CmsObject cms, CmsResource file, ServletRequest req, ServletResponse res) {
  
          throw new CmsRuntimeException(
              Messages.get().container(Messages.ERR_SERVICE_UNSUPPORTED_1, getClass().getName()));
      }
  }