/*
    * Licensed under the GPL License. You may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *   https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
    *
    * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
    * WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
    * PURPOSE.
   */
  package psiprobe.controllers.jsp;
  
  import jakarta.servlet.ServletConfig;
  import jakarta.servlet.ServletContext;
  import jakarta.servlet.http.HttpServletRequest;
  import jakarta.servlet.http.HttpServletResponse;
  import jakarta.servlet.http.HttpSession;
  
  import java.io.InputStream;
  
  import org.apache.catalina.Context;
  import org.apache.jasper.EmbeddedServletOptions;
  import org.apache.jasper.Options;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.annotation.Value;
  import org.springframework.stereotype.Controller;
  import org.springframework.web.bind.ServletRequestUtils;
  import org.springframework.web.bind.annotation.RequestMapping;
  import org.springframework.web.servlet.ModelAndView;
  
  import psiprobe.Utils;
  import psiprobe.controllers.AbstractContextHandlerController;
  import psiprobe.model.jsp.Item;
  import psiprobe.model.jsp.Summary;
  
  /**
   * The Class ViewSourceController.
   */
  @Controller
  public class ViewSourceController extends AbstractContextHandlerController {
  
    /** The Constant logger. */
    private static final Logger logger = LoggerFactory.getLogger(ViewSourceController.class);
  
    @RequestMapping(path = "/app/viewsource.htm")
    @Override
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response)
        throws Exception {
      return super.handleRequest(request, response);
    }
  
    @Override
    protected ModelAndView handleContext(String contextName, Context context,
        HttpServletRequest request, HttpServletResponse response) throws Exception {
  
      String jspName = ServletRequestUtils.getStringParameter(request, "source");
      boolean highlight = ServletRequestUtils.getBooleanParameter(request, "highlight", true);
      HttpSession session = request.getSession(false);
      Summary summary = session == null ? null
          : (Summary) session.getAttribute(DisplayJspController.SUMMARY_ATTRIBUTE);
  
      if (jspName != null && summary != null && contextName.equals(summary.getName())) {
  
        Item item = summary.getItems().get(jspName);
  
        if (item != null) {
          // replace "\" with "/"
          jspName = jspName.replace('\\', '/');
  
          // remove cheeky "../" from the path to avoid exploits
          while (jspName.contains("../")) {
            jspName = jspName.replace("../", "");
          }
  
          if (containerWrapper.getTomcatContainer().resourceExists(jspName, context)) {
            ServletContext sctx = context.getServletContext();
            ServletConfig scfg = (ServletConfig) context.findChild("jsp");
            Options opt = new EmbeddedServletOptions(scfg, sctx);
            String descriptorPageEncoding =
                opt.getJspConfig().findJspProperty(jspName).getPageEncoding();
  
            if (descriptorPageEncoding != null && !descriptorPageEncoding.isEmpty()) {
              item.setEncoding(descriptorPageEncoding);
            } else {
  
              /*
               * we have to read the JSP twice, once to figure out the content encoding the second
               * time to read the actual content using the correct encoding
               */
              try (InputStream encodedStream =
                  containerWrapper.getTomcatContainer().getResourceStream(jspName, context)) {
                item.setEncoding(Utils.getJspEncoding(encodedStream));
              }
            }
            try (InputStream jspStream =
                containerWrapper.getTomcatContainer().getResourceStream(jspName, context)) {
              if (highlight) {
                request.setAttribute("highlightedContent",
                   Utils.highlightStream(jspName, jspStream, "xhtml", item.getEncoding()));
             } else {
               request.setAttribute("content", Utils.readStream(jspStream, item.getEncoding()));
             }
           }
 
         } else {
           logger.error("{} does not exist", jspName);
         }
 
         request.setAttribute("item", item);
 
       } else {
         logger.error("jsp name passed is not in the summary, ignored");
       }
     } else {
       if (jspName == null) {
         logger.error("Passed empty 'source' parameter");
       }
       if (summary == null) {
         logger.error("Session has expired or there is no summary");
       }
     }
     return new ModelAndView(getViewName());
   }
 
   @Value("view_jsp_source")
   @Override
   public void setViewName(String viewName) {
     super.setViewName(viewName);
   }
 
 }