/**
    * Copyright 2005-2011 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.rice.kns.web.struts.action;
  
  import org.apache.log4j.Logger;
  import org.apache.struts.Globals;
  import org.apache.struts.action.Action;
  import org.apache.struts.action.ActionForm;
  import org.apache.struts.action.ActionForward;
  import org.apache.struts.action.ActionMapping;
  import org.kuali.rice.core.api.util.RiceConstants;
  import org.kuali.rice.kns.util.IncidentReportUtils;
  import org.kuali.rice.kns.web.struts.form.KualiExceptionIncidentForm;
  import org.kuali.rice.krad.exception.KualiExceptionIncident;
  import org.kuali.rice.krad.service.KRADServiceLocatorWeb;
  import org.kuali.rice.krad.service.KualiExceptionIncidentService;
  import org.kuali.rice.krad.util.KRADConstants;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * This is the struts action class for handling the exception for Kuali
   * applications.
   * 
   */
  public class KualiExceptionHandlerAction extends Action {
  	private static final Logger LOG = Logger
  			.getLogger(KualiExceptionHandlerAction.class);
  
  	/**
  	 * This overridden method dispatches action to be taken based on
  	 * "methodToCall" parameter. The exception is processed when there is no
  	 * "methodToCall" specified.
  	 * 
  	 * @see org.apache.struts.action.Action#execute(org.apache.struts.action.ActionMapping,
  	 *      org.apache.struts.action.ActionForm,
  	 *      javax.servlet.http.HttpServletRequest,
  	 *      javax.servlet.http.HttpServletResponse)
  	 */
  	public ActionForward execute(ActionMapping mapping, ActionForm form,
  			HttpServletRequest request, HttpServletResponse response)
  			throws Exception {
  		return executeException(mapping, form, request, response);
  	}
  
  	/**
  	 * This overridden method processes the exception and post exception (when
  	 * user either submit/cancel the exception JSP page).
  	 * <ul>
  	 * <li>ProcessDefinition application Exception - Exception is stored in Http Request</li>
  	 * <li>ProcessDefinition exception incident reporting - No exception, only form data</li>
  	 * </ul>
  	 * 
  	 * @see org.apache.struts.action.Action#execute(org.apache.struts.action.ActionMapping,
  	 *      org.apache.struts.action.ActionForm,
  	 *      javax.servlet.http.HttpServletRequest,
  	 *      javax.servlet.http.HttpServletResponse)
  	 */
  	public ActionForward executeException(ActionMapping mapping,
  			ActionForm form, HttpServletRequest request,
  			HttpServletResponse response) throws Exception {
  
  		if (LOG.isDebugEnabled()) {
  			String lm = String.format("ENTRY %s%n%s", form.getClass()
  					.getSimpleName(), request.getRequestURI());
  			LOG.debug(lm);
  		}
  
  		// Get exception thrown
  		Exception e = (Exception) request.getAttribute(Globals.EXCEPTION_KEY);
  
  		// Initialize defined action mapping from struts-config
  		ActionForward returnForward = null;
  
  		// In case there is no exception, either a post back after page was
  		// filled in
  		// or just an error from directly accessing this struts action
  		if (e == null) {
  			if (form instanceof KualiExceptionIncidentForm) {
  				KualiExceptionIncidentForm formObject = (KualiExceptionIncidentForm) form;
  				// Manage conditions: submit or cancel
  				if (!formObject.isCancel()) {
 					// Locate the post exception handler service. The service id
 					// is
 					// defined in the application properties
 					// Only process the post exception handling when the
 					// service
 					// is specified
 					KualiExceptionIncidentService reporterService = KRADServiceLocatorWeb
 							.getKualiExceptionIncidentService();
 					// An instance of the ExceptionIncident is created by
 					// the
 					// ExceptionIncidentService
 					Map reducedMap = new HashMap();
 					Enumeration<String> names = request.getParameterNames();
 					while (names.hasMoreElements()) {
 						String name = names.nextElement();
 						reducedMap.put(name, request.getParameter(name));
 					}
 					KualiExceptionIncident exceptionIncident = reporterService
 							.getExceptionIncident(reducedMap);
 					// Report the incident
 					reporterService.report(exceptionIncident);
 				} else {
 					// Set return after canceling
 					ActionForward cancelForward = mapping
 							.findForward(KRADConstants.MAPPING_CANCEL);
 					if (cancelForward == null) {
 						cancelForward = returnForward;
 					} else {
 						returnForward = cancelForward;
 					}
 				}
 			}
 		} else {
 			// ProcessDefinition the received exception from HTTP request
 			returnForward = processException(mapping, form, request, e);
 		}
 
 		// Not specified, return
 		if (returnForward == null) {
 			returnForward = mapping.findForward(KRADConstants.MAPPING_CLOSE);
 		}
 
 		if (LOG.isDebugEnabled()) {
 			String lm = String.format("EXIT %s",
 					(returnForward == null) ? "null" : returnForward.getPath());
 			LOG.debug(lm);
 		}
 
 		return returnForward;
 	}
 
 	/**
 	 * This method process the caught exception by creating an exception
 	 * information properties list and forward these properties to the exception
 	 * incident handler JSP.
 	 * 
 	 * @param exception
 	 * @param mapping
 	 * @param request
 	 * @param documentId
 	 *            Id of the document that Struts threw exception during its
 	 *            processing. null if not the document processing that caused
 	 *            the exception
 	 * @return
 	 * @throws Exception
 	 */
 	@SuppressWarnings("unchecked")
 	protected ActionForward processException(ActionMapping mapping,
 			ActionForm form, HttpServletRequest request, Exception exception)
 			throws Exception {
 		// Only process the exception handling when the service
 		// is specified
 		KualiExceptionIncidentService reporterService = KRADServiceLocatorWeb
 				.getKualiExceptionIncidentService();
 		// Get exception properties from the Http Request
 		Map<String, String> properties = (Map<String, String>) request
 				.getAttribute(IncidentReportUtils.EXCEPTION_PROPERTIES);
 		// Construct the exception incident object
 		KualiExceptionIncident ei = reporterService.getExceptionIncident(
 				exception, properties);
 		// Set full exception properties in Http Request and forward to JSP
 		request.setAttribute(KualiExceptionHandlerAction.class
 				.getName(), ei.toProperties());
 		return mapping.findForward(RiceConstants.MAPPING_BASIC);
 	}
 }