/*
    * $Id: GWUIServlet.java 1537 2011-07-27 15:34:04Z hoheisel $
    *
    * Copyright (c) 2005-2006, The K-Wf Grid Consortium
    * Fraunhofer Institute for Computer Architecture and Software Technology
    * See http://www.kwfgrid.eu and http://www.first.fraunhofer.de for more details.
    */
   
   package net.kwfgrid.gwes.servlet;
  
  import org.antlr.stringtemplate.StringTemplate;
  import org.apache.log4j.Logger;
  
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import java.io.IOException;
  import java.io.PrintWriter;
  import java.net.MalformedURLException;
  
  import net.kwfgrid.gwes.client.RemoteGWES;
  import net.kwfgrid.gwes.exception.GWESException;
  
  /**
   * Servlet for creating html for the GWUI applet.
   *
   * @author Andreas Hoheisel
   *         (<a href="http://www.andreas-hoheisel.de">www.andreas-hoheisel.de</a>)
   * @version $Id: GWUIServlet.java 1537 2011-07-27 15:34:04Z hoheisel $
   */
  public class GWUIServlet extends HttpServlet {
  
      final static Logger logger = Logger.getLogger(GWUIServlet.class);
      private static GWESProperties pr;
  
      protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
          ServletLogger.log(request);
  
          //read gwes.properties
          if (pr == null) pr = GWESProperties.getInstance("/gwes.properties");
  
          response.setContentType("text/html");
          PrintWriter out = response.getWriter();
          String error = null;
          String info = null;
  
          // get user
          String userID = request.getRemoteUser();
          if (userID == null) userID = "nn";
  
          // get workflow ID
          String workflowID = request.getParameter("workflowid");
          if (workflowID == null) {
              workflowID = (String) request.getSession().getAttribute("workflowid");
          } else {
              logger.debug("session workflow = "+workflowID);
              request.getSession().setAttribute("workflowid",workflowID);
          }
          if (workflowID == null || workflowID.length() == 0) {
              info = "Please select the workflow in the <a href=\""+pr.gwesBaseUrlExternal+"/servlet/WorkflowListServlet\">Workflow List</a> first!";
          }
  
          try {
              // check workflowID
              if (workflowID != null && !checkWorkflowID(workflowID, request.getUserPrincipal().getName())) {
                  error = "Not able to display the workflow graph, because the selected Workflow is not in memory! Please select a workflow with level \"MEMORY\" from the <a href=\""+pr.gwesBaseUrlExternal+"/servlet/WorkflowListServlet\">Workflow List</a> or upload a <a href=\""+pr.gwesBaseUrlExternal+"/servlet/WorkflowUploadServlet\">New Workflow</a>";
                  workflowID = null;
              }
          } catch (Throwable e) {
              error = "Not able to access the GWES: "+e;
          }
  
  
          try {
              StringTemplate t = Template.getStringTemplateGroup("html_gwes-servlets").getInstanceOf("graph");
              t.setAttribute("menu", new Menu(pr.gwesBaseUrlExternal, "Graph"));
              if (error != null) t.setAttribute("error", error);
              if (info != null) t.setAttribute("info", info);
              t.setAttribute("width", pr.width);
              t.setAttribute("height", pr.height);
              if (workflowID != null) t.setAttribute("workflowID", workflowID);
              t.setAttribute("userID", userID);
              t.setAttribute("gwesBaseUrlExternal", pr.gwesBaseUrlExternal);
              t.setAttribute("graphvizServiceUri", pr.graphvizServiceUri);
              t.setAttribute("gworkflowdlXsdPath", pr.gworkflowdlXsdPath);
              out.print(t.toString());
          } catch (Exception e) {
              out.println("<hr><b>ERROR connecting to GWES: " + e + "</b>");
              out.println("<pre>");
              e.printStackTrace(out);
              out.println("</pre>");
              out.println("<hr>");
          }
      }
  
      protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
          doGet(request, response);
      }
 
     private boolean checkWorkflowID(String workflowID, String userID) throws Exception, GWESException {
         String[] workflowIDs = RemoteGWES.getInstance().getWorkflowIDs(1, userID);
         if (workflowIDs == null) return false;
         for (String wf : workflowIDs) {
             if (wf.equals(workflowID)) return true;
         }
         return false;
     }
 
 }