/**
 * Copyright 2005-2016 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.commons.lang.StringUtils;
import org.apache.log4j.Logger;
import org.apache.log4j.MDC;
import org.apache.ojb.broker.OptimisticLockException;
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.apache.struts.action.InvalidCancelException;
import org.apache.struts.action.RequestProcessor;
import org.apache.struts.config.FormBeanConfig;
import org.apache.struts.config.ForwardConfig;
import org.apache.struts.util.RequestUtils;
import org.kuali.rice.core.api.config.property.Config;
import org.kuali.rice.core.api.config.property.ConfigContext;
import org.kuali.rice.core.api.config.property.ConfigurationService;
import org.kuali.rice.core.api.util.RiceConstants;
import org.kuali.rice.core.api.util.RiceKeyConstants;
import org.kuali.rice.kns.exception.FileUploadLimitExceededException;
import org.kuali.rice.kns.service.KNSServiceLocator;
import org.kuali.rice.kns.service.SessionDocumentService;
import org.kuali.rice.kns.util.ErrorContainer;
import org.kuali.rice.kns.util.InfoContainer;
import org.kuali.rice.kns.util.KNSConstants;
import org.kuali.rice.kns.util.KNSGlobalVariables;
import org.kuali.rice.kns.util.WarningContainer;
import org.kuali.rice.kns.util.WebUtils;
import org.kuali.rice.kns.web.EditablePropertiesHistoryHolder;
import org.kuali.rice.kns.web.struts.form.KualiDocumentFormBase;
import org.kuali.rice.kns.web.struts.form.KualiForm;
import org.kuali.rice.kns.web.struts.form.pojo.PojoForm;
import org.kuali.rice.krad.UserSession;
import org.kuali.rice.krad.document.Document;
import org.kuali.rice.krad.exception.ValidationException;
import org.kuali.rice.krad.service.KRADServiceLocator;
import org.kuali.rice.krad.service.KRADServiceLocatorInternal;
import org.kuali.rice.krad.util.GlobalVariables;
import org.kuali.rice.krad.util.KRADConstants;
import org.kuali.rice.krad.util.KRADUtils;
import org.kuali.rice.krad.util.MessageMap;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionTemplate;
import org.springmodules.orm.ojb.OjbOperationException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;

/**
 * This class handles setup of user session and restoring of action form.
 * 
 * 
 */
public class KualiRequestProcessor extends RequestProcessor {
        
        private static final String MDC_DOC_ID = "docId";
        private static final String PREVIOUS_REQUEST_EDITABLE_PROPERTIES_GUID_PARAMETER_NAME = "actionEditablePropertiesGuid";

        private static Logger LOG = Logger.getLogger(KualiRequestProcessor.class);

        private SessionDocumentService sessionDocumentService;
        private PlatformTransactionManager transactionManager;
        
        @Override
        public void process(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
                if ( LOG.isInfoEnabled() ) {
                        LOG.info(new StringBuffer("Started processing request: '").append(request.getRequestURI()).append("' w/ query string: '").append(request.getQueryString()).append("'"));
                }

                try { 
                        strutsProcess(request, response);
                } catch (FileUploadLimitExceededException e) {
                        ActionForward actionForward = processException(request, response, e, e.getActionForm(), e.getActionMapping());
                        processForwardConfig(request, response, actionForward);
                } finally {
                        KNSGlobalVariables.setKualiForm(null);
                }
                        
                try {
                        ActionForm form = WebUtils.getKualiForm(request);
                        
                        if (form != null && form instanceof KualiDocumentFormBase) {
                                String docId = ((KualiDocumentFormBase) form).getDocId();
                                if (docId != null) { MDC.put(MDC_DOC_ID, docId); }
                        }

                        String refreshCaller = request.getParameter(KRADConstants.REFRESH_CALLER);
                        if (form!=null && KualiDocumentFormBase.class.isAssignableFrom(form.getClass()) 
                                        && !KRADConstants.QUESTION_REFRESH.equalsIgnoreCase(refreshCaller)) {
                                KualiDocumentFormBase docForm = (KualiDocumentFormBase) form;
                                Document document = docForm.getDocument();
                                String docFormKey = docForm.getFormKey();

                                UserSession userSession = (UserSession) request.getSession().getAttribute(KRADConstants.USER_SESSION_KEY);

                                if (WebUtils.isDocumentSession(document, docForm)) {
                                        getSessionDocumentService().setDocumentForm(docForm, userSession, request.getRemoteAddr());
                                }

                                Boolean exitingDocument = (Boolean) request.getAttribute(KRADConstants.EXITING_DOCUMENT);

                                if (exitingDocument != null && exitingDocument.booleanValue()) {
                                        // remove KualiDocumentFormBase object from session and
                                        // table.
                                        getSessionDocumentService().purgeDocumentForm(docForm.getDocument().getDocumentNumber(), docFormKey, userSession, request.getRemoteAddr());
                                }
                        }

                        if ( LOG.isInfoEnabled() ) {
                                LOG.info(new StringBuffer("Finished processing request: '").append(request.getRequestURI()).append("' w/ query string: '").append(request.getQueryString()).append("'"));
                        }

                } finally {
                        // MDC docId key is set above, and also during super.process() in the call to processActionForm
                        MDC.remove(MDC_DOC_ID);
                }

        }
        
        @Override
        protected boolean processPreprocess(HttpServletRequest request, HttpServletResponse response) {
        final UserSession session = KRADUtils.getUserSessionFromRequest(request);
        
        if (session == null) {
                throw new IllegalStateException("the user session has not been established");
        }
        GlobalVariables.setUserSession(session);
        KNSGlobalVariables.clear();
                return true;
        }
        
        /**
     * <p>ProcessDefinition an <code>HttpServletRequest</code> and create the
     * corresponding <code>HttpServletResponse</code> or dispatch
     * to another resource.</p>
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a processing exception occurs
     */
    public void strutsProcess(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

        // Wrap multipart requests with a special wrapper
        request = processMultipart(request);

        // Identify the path component we will use to select a mapping
        String path = processPath(request, response);
        if (path == null) {
            return;
        }
        
        if (log.isDebugEnabled()) {
            log.debug("Processing a '" + request.getMethod() +
                      "' for path '" + path + "'");
        }

        // Select a Locale for the current user if requested
        processLocale(request, response);

        // Set the content type and no-caching headers if requested
        processContent(request, response);
        processNoCache(request, response);

        // General purpose preprocessing hook
        if (!processPreprocess(request, response)) {
            return;
        }
        
        this.processCachedMessages(request, response);

        // Identify the mapping for this request
        ActionMapping mapping = processMapping(request, response, path);
        if (mapping == null) {
            return;
        }

        // Check for any role required to perform this action
        if (!processRoles(request, response, mapping)) {
            return;
        }

        processFormActionAndForward(request, response, mapping);

    }

    public void processFormActionAndForward(final HttpServletRequest request, final HttpServletResponse response, final ActionMapping mapping) throws ServletException, IOException {
        ActionForm form = processActionForm(request, response, mapping);
        processPopulate(request, response, form, mapping);

        // Create or acquire the Action instance to process this request
                Action action = processActionCreate(request, response, mapping);

        if (action != null) {
            // Call the Action instance itself
                    ActionForward forward = processActionPerform(request, response, action, form, mapping);

            if (forward != null) {
                if (forward.getRedirect() && forward.getName()!= null && forward.getName().equals(KRADConstants.KRAD_INITIATED_DOCUMENT_VIEW_NAME)) {
                    LOG.info("Attempt to open a document with a status of \"Initiated\" detected");
                    return;
                }
                // ProcessDefinition the returned ActionForward instance
                            processForwardConfig(request, response, forward);
            }
        }
    }


        /**
         * This method gets the document number from the request.  The request should have been processed already 
         * before this is called if it is multipart.  
         * 
         * @param request
         * @return the document number, or null if one can't be found in the request.
         */
        private String getDocumentNumber(HttpServletRequest request) {
                String documentNumber = request.getParameter(KRADConstants.DOCUMENT_DOCUMENT_NUMBER);

                // from lookup pages.
                if (documentNumber == null) {
                        documentNumber = request.getParameter(KRADConstants.DOC_NUM);
                }
                
                if (documentNumber == null) {
                        documentNumber = request.getParameter("documentId");
                }
                
                return documentNumber;
        }

        /**
         * Hooks into populate process to call form populate method if form is an
         * instanceof PojoForm.
         */
        @Override
        protected void processPopulate(HttpServletRequest request, HttpServletResponse response, ActionForm form, ActionMapping mapping) throws ServletException {
                if (form instanceof KualiForm) {
                        // Add the ActionForm to GlobalVariables
                        // This will allow developers to retrieve both the Document and any
                        // request parameters that are not
                        // part of the Form and make them available in ValueFinder classes
                        // and other places where they are needed.
                        KNSGlobalVariables.setKualiForm((KualiForm) form);
                }

                // if not PojoForm, call struts populate
                if (!(form instanceof PojoForm)) {
                        super.processPopulate(request, response, form, mapping);
                        return;
                }
                
                final String previousRequestGuid = request.getParameter(KualiRequestProcessor.PREVIOUS_REQUEST_EDITABLE_PROPERTIES_GUID_PARAMETER_NAME);

                ((PojoForm)form).clearEditablePropertyInformation();
                ((PojoForm)form).registerStrutsActionMappingScope(mapping.getScope());
                
                String multipart = mapping.getMultipartClass();
                if (multipart != null) {
                        request.setAttribute(Globals.MULTIPART_KEY, multipart);
                }

                form.setServlet(this.servlet);
                form.reset(mapping, request);

                ((PojoForm)form).setPopulateEditablePropertiesGuid(previousRequestGuid);
                // call populate on ActionForm
                ((PojoForm) form).populate(request);
                request.setAttribute("UnconvertedValues", ((PojoForm) form).getUnconvertedValues().keySet());
                request.setAttribute("UnconvertedHash", ((PojoForm) form).getUnconvertedValues());
        }

        /**
         * Hooks into validate to catch any errors from the populate, and translate
         * the ErrorMap to ActionMessages.
         */
        @Override
        protected boolean processValidate(HttpServletRequest request, HttpServletResponse response, ActionForm form, ActionMapping mapping) throws IOException, ServletException, InvalidCancelException {

                // skip form validate if we had errors from populate
                if (GlobalVariables.getMessageMap().hasNoErrors()) {
                        if (form == null) {
                                return (true);
                        }
                        // Was this request cancelled?
                        if (request.getAttribute(Globals.CANCEL_KEY) != null) {
                                if (LOG.isDebugEnabled()) {
                                        LOG.debug(" Cancelled transaction, skipping validation");
                                }
                                return (true);
                        }

                        // Has validation been turned off for this mapping?
                        if (!mapping.getValidate()) {
                                return (true);
                        }

                        // call super to call forms validate
                        super.processValidate(request, response, form, mapping);
                }

                publishMessages(request);
                if (!GlobalVariables.getMessageMap().hasNoErrors()) {
                        // Special handling for multipart request
                        if (form.getMultipartRequestHandler() != null) {
                                if (LOG.isDebugEnabled()) {
                                        LOG.debug("  Rolling back multipart request");
                                }
                                form.getMultipartRequestHandler().rollback();
                        }

                        // Fix state that could be incorrect because of validation failure
                        if (form instanceof PojoForm) {
                                ((PojoForm) form).processValidationFail();
                        }

                        // Was an input path (or forward) specified for this mapping?
                        String input = mapping.getInput();
                        if (input == null) {
                                if (LOG.isDebugEnabled()) {
                                        LOG.debug("  Validation failed but no input form available");
                                }
                                response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, getInternal().getMessage("noInput", mapping.getPath()));
                                return (false);
                        }

                        if (moduleConfig.getControllerConfig().getInputForward()) {
                                ForwardConfig forward = mapping.findForward(input);
                                processForwardConfig(request, response, forward);
                        } else {
                                internalModuleRelativeForward(input, request, response);
                        }

                        return (false);
                }
                return true;
        }

        /**
         * Checks for return from a lookup or question, and restores the action form
         * stored under the request parameter docFormKey.
         */
        @Override
        protected ActionForm processActionForm(HttpServletRequest request, HttpServletResponse response, ActionMapping mapping) {
                
                String documentNumber = getDocumentNumber(request);
                if (documentNumber != null) { MDC.put(MDC_DOC_ID, documentNumber); }
                
                UserSession userSession = (UserSession) request.getSession().getAttribute(KRADConstants.USER_SESSION_KEY);

                String docFormKey = request.getParameter(KRADConstants.DOC_FORM_KEY);
                String methodToCall = request.getParameter(KRADConstants.DISPATCH_REQUEST_PARAMETER);
                String refreshCaller = request.getParameter(KRADConstants.REFRESH_CALLER);
//              String searchListRequestKey = request.getParameter(KRADConstants.SEARCH_LIST_REQUEST_KEY);
                String documentWebScope = request.getParameter(KRADConstants.DOCUMENT_WEB_SCOPE);

                if (mapping.getPath().startsWith(KRADConstants.REFRESH_MAPPING_PREFIX) || KRADConstants.RETURN_METHOD_TO_CALL.equalsIgnoreCase(methodToCall) ||
                                KRADConstants.QUESTION_REFRESH.equalsIgnoreCase(refreshCaller) || KRADConstants.TEXT_AREA_REFRESH.equalsIgnoreCase(refreshCaller) || KRADConstants
                .SESSION_SCOPE.equalsIgnoreCase(documentWebScope)) {
                        ActionForm form = null;
                        // check for search result storage and clear
                        GlobalVariables.getUserSession().removeObjectsByPrefix(KRADConstants.SEARCH_LIST_KEY_PREFIX);

                        // We put different type of forms such as document form, lookup form
                        // in session but we only store document form in
                        // database.
                        if (userSession.retrieveObject(docFormKey) != null) {
                                LOG.debug("getDecomentForm KualiDocumentFormBase from session");
                                form = (ActionForm) userSession.retrieveObject(docFormKey);
                        } else if (StringUtils.isNotBlank(documentNumber)) {
                                form = getSessionDocumentService().getDocumentForm(documentNumber, docFormKey, userSession, request.getRemoteAddr());
                        }
                        request.setAttribute(mapping.getAttribute(), form);
                        if (!KRADConstants.SESSION_SCOPE.equalsIgnoreCase(documentWebScope)) {
                                userSession.removeObject(docFormKey);
                        }
                        // we should check whether this is a multipart request because we
                        // could have had a combination of query parameters and a multipart
                        // request
                        String contentType = request.getContentType();
                        String method = request.getMethod();
                        if (("POST".equalsIgnoreCase(method) && contentType != null && contentType.startsWith("multipart/form-data"))) {
                                // this method parses the multipart request and adds new
                                // non-file parameters into the request
                                WebUtils.getMultipartParameters(request, null, form, mapping);
                        }
                        // The form can be null if the document is not a session document
                        if (form != null) {
                                return form;
                        }
                }

                // Rice has the ability to limit file upload sizes on a per-form basis,
                // so the max upload sizes may be accessed by calling methods on
                // PojoFormBase.
                // This requires that we are able know the file upload size limit (i.e.
                // retrieve a form instance) before we parse a mulitpart request.
                ActionForm form = super.processActionForm(request, response, mapping);

                // for sessiondocument with multipart request
                String contentType = request.getContentType();
                String method = request.getMethod();

                if ("GET".equalsIgnoreCase(method) && StringUtils.isNotBlank(methodToCall) && form instanceof PojoForm &&
                                ((PojoForm) form).getMethodToCallsToBypassSessionRetrievalForGETRequests().contains(methodToCall)) {
                        return createNewActionForm(mapping, request);
                }
                
                // if we have a multipart request, parse it and return the stored form
                // from session if the doc form key is not blank. If it is blank, then
                // we just return the form
                // generated from the superclass processActionForm method. Either way,
                // we need to parse the mulitpart request now so that we may determine
                // what the value of the doc form key is.
                // This is generally against the contract of processActionForm, because
                // processPopulate should be responsible for parsing the mulitpart
                // request, but we need to parse it now
                // to determine the doc form key value.
                if (("POST".equalsIgnoreCase(method) && contentType != null && contentType.startsWith("multipart/form-data"))) {
                        WebUtils.getMultipartParameters(request, null, form, mapping);
                        docFormKey = request.getParameter(KRADConstants.DOC_FORM_KEY);
                        documentWebScope = request.getParameter(KRADConstants.DOCUMENT_WEB_SCOPE);

                        documentNumber = getDocumentNumber(request);

                        if (KRADConstants.SESSION_SCOPE.equalsIgnoreCase(documentWebScope) ||
                                        (form instanceof KualiDocumentFormBase && WebUtils
                            .isDocumentSession(((KualiDocumentFormBase) form).getDocument(),
                                    (KualiDocumentFormBase) form))) {

                                Object userSessionObject = userSession.retrieveObject(docFormKey);
                                if ( userSessionObject != null &&  userSessionObject instanceof ActionForm ) {
                                        LOG.debug("getDocumentForm KualiDocumentFormBase from session");
                                        form = (ActionForm) userSessionObject;
                                } else {
                                        ActionForm tempForm = getSessionDocumentService().getDocumentForm(documentNumber, docFormKey, userSession, request.getRemoteAddr());
                                        if ( tempForm != null ) {
                                                form = tempForm;
                                        }
                                }

                                request.setAttribute(mapping.getAttribute(), form);
                                if (form != null) {
                                        return form;
                                }
                        }
                }
                return form;
        }

        /**
         * Hook into action perform to handle errors in the error map and catch
         * exceptions.
         * 
         * <p>
         * A transaction is started prior to the execution of the action. This
         * allows for the action code to execute efficiently without the need for
         * using PROPAGATION_SUPPORTS in the transaction definitions. The
         * PROPAGATION_SUPPORTS propagation type does not work well with JTA.
         */
        @Override
        protected ActionForward processActionPerform(final HttpServletRequest request, final HttpServletResponse response, final Action action, final ActionForm form, final ActionMapping mapping) throws IOException, ServletException {
                try {
            TransactionTemplate template = new TransactionTemplate(getTransactionManager());
                        ActionForward forward = null;
                        try {
                                forward = (ActionForward) template.execute(new TransactionCallback() {
                                        public Object doInTransaction(TransactionStatus status) {
                                                ActionForward actionForward = null;
                                                try {
                                                        actionForward = action.execute(mapping, form, request, response);
                                                } catch (Exception e) {
                            if (e.getMessage()!= null && e.getMessage().equals(KRADConstants.KRAD_INITIATED_DOCUMENT_VIEW_NAME)) {
                                ConfigurationService kualiConfigurationService = KRADServiceLocator.getKualiConfigurationService();
                                StringBuffer sb = new StringBuffer();
                                sb.append(kualiConfigurationService.getPropertyValueAsString(KRADConstants.KRAD_URL_KEY));
                                sb.append(kualiConfigurationService.getPropertyValueAsString(KRADConstants.KRAD_INITIATED_DOCUMENT_URL_KEY));
                                return new ActionForward(KRADConstants.KRAD_INITIATED_DOCUMENT_VIEW_NAME, sb.toString() ,true);
                            }
                                                        // the doInTransaction method has no means for
                                                        // throwing exceptions, so we will wrap the
                                                        // exception in
                                                        // a RuntimeException and re-throw. The one caveat
                                                        // here is that this will always result in
                                                        // the
                                                        // transaction being rolled back (since
                                                        // WrappedRuntimeException is a runtime exception).
                                                        throw new WrappedRuntimeException(e);
                                                }
                                                if (status.isRollbackOnly()) {
                                                        // this means that the struts action execution
                                                        // caused the transaction to rollback, we want to
                                                        // go ahead
                                                        // and trigger the rollback by throwing an exception
                                                        // here but then return the action forward
                                                        // from this method
                                                        throw new WrappedActionForwardRuntimeException(actionForward);
                                                }
                                                return actionForward;
                                        }
                                });
                        } catch (WrappedActionForwardRuntimeException e) {
                                forward = e.getActionForward();
                        }

                        publishMessages(request);
                        saveMessages(request);
                        saveAuditErrors(request);

                        if (form instanceof PojoForm) {
                                if (((PojoForm)form).getEditableProperties() == null
                                                || ((PojoForm)form).getEditableProperties().isEmpty()) {
                                        EditablePropertiesHistoryHolder holder = (EditablePropertiesHistoryHolder) GlobalVariables.getUserSession().getObjectMap().get(
                            KRADConstants.EDITABLE_PROPERTIES_HISTORY_HOLDER_ATTR_NAME);
                                    if (holder == null) {
                                        holder = new EditablePropertiesHistoryHolder();
                                    }

                                        final String guid = holder.addEditablePropertiesToHistory(((PojoForm)form).getEditableProperties());
                                    ((PojoForm)form).setActionEditablePropertiesGuid(guid);
                                    GlobalVariables.getUserSession().addObject(KRADConstants.EDITABLE_PROPERTIES_HISTORY_HOLDER_ATTR_NAME, holder);
                                }
                        }

                        return forward;

                } catch (Exception e) {
                        if (e instanceof WrappedRuntimeException) {
                                e = (Exception) e.getCause();
                        }
                        if (e instanceof ValidationException) {
                                // add a generic error message if there are none
                                if (GlobalVariables.getMessageMap().hasNoErrors()) {

                                        GlobalVariables.getMessageMap().putError(KRADConstants.GLOBAL_ERRORS, RiceKeyConstants.ERROR_CUSTOM, e.getMessage());
                                }

                                if (form instanceof PojoForm) {
                                        if (((PojoForm)form).getEditableProperties() == null
                                                        || ((PojoForm)form).getEditableProperties().isEmpty()) {
                                            EditablePropertiesHistoryHolder holder = (EditablePropertiesHistoryHolder) GlobalVariables.getUserSession().getObjectMap().get(
                                KRADConstants.EDITABLE_PROPERTIES_HISTORY_HOLDER_ATTR_NAME);
                                        if (holder == null) {
                                            holder = new EditablePropertiesHistoryHolder();
                                        }

                                            final String guid = holder.addEditablePropertiesToHistory(((PojoForm)form).getEditableProperties());
                                        ((PojoForm)form).setActionEditablePropertiesGuid(guid);
                                        GlobalVariables.getUserSession().addObject(KRADConstants.EDITABLE_PROPERTIES_HISTORY_HOLDER_ATTR_NAME, holder);
                                        }
                                }                       
                                // display error messages and return to originating page
                                publishMessages(request);
                                return mapping.findForward(RiceConstants.MAPPING_BASIC);
                        }

                        publishMessages(request);

                        return (processException(request, response, e, form, mapping));
                }
        }

    private static class WrappedActionForwardRuntimeException extends RuntimeException {
                private ActionForward actionForward;

                public WrappedActionForwardRuntimeException(ActionForward actionForward) {
                        this.actionForward = actionForward;
                }

                public ActionForward getActionForward() {
                        return actionForward;
                }
        }

        /**
         * Adds more detailed logging for unhandled exceptions
         * 
         * @see org.apache.struts.action.RequestProcessor#processException(HttpServletRequest,
         *      HttpServletResponse, Exception, ActionForm, ActionMapping)
         */
        @Override
        protected ActionForward processException(HttpServletRequest request, HttpServletResponse response, Exception exception, ActionForm form, ActionMapping mapping) throws IOException, ServletException {
                ActionForward actionForward = null;

                try {
                        actionForward = super.processException(request, response, exception, form, mapping);
                } catch (IOException e) {
                        logException(e);
                        throw e;
                } catch (ServletException e) {
                        // special case, to make OptimisticLockExceptions easier to read
                        Throwable rootCause = e.getRootCause();
                        if (rootCause instanceof OjbOperationException) {
                                OjbOperationException ooe = (OjbOperationException) rootCause;

                                Throwable subcause = ooe.getCause();
                                if (subcause instanceof OptimisticLockException) {
                                        OptimisticLockException ole = (OptimisticLockException) subcause;

                                        StringBuffer message = new StringBuffer(e.getMessage());

                                        Object sourceObject = ole.getSourceObject();
                                        if (sourceObject != null) {
                                                message.append(" (sourceObject is ");
                                                message.append(sourceObject.getClass().getName());
                                                message.append(")");
                                        }

                                        e = new ServletException(message.toString(), rootCause);
                                }
                        }

                        logException(e);
                        throw e;
                }
                return actionForward;
        }

        private void logException(Exception e) {
                LOG.error("unhandled exception thrown by KualiRequestProcessor.processActionPerform", e);
        }

        /**
         * Checks for errors in the error map and transforms them to struts action
         * messages then stores in the request.
         */
        private void publishMessages(HttpServletRequest request) {
                MessageMap errorMap = GlobalVariables.getMessageMap();
                if (!errorMap.hasNoErrors()) {
                        ErrorContainer errorContainer = new ErrorContainer(errorMap);

                        request.setAttribute("ErrorContainer", errorContainer);
                        request.setAttribute(Globals.ERROR_KEY, errorContainer.getRequestErrors());
                        request.setAttribute("ErrorPropertyList", errorContainer.getErrorPropertyList());
                }
                
                if (errorMap.hasWarnings()) {
                        WarningContainer warningsContainer = new WarningContainer(errorMap);
                        
                        request.setAttribute("WarningContainer", warningsContainer);
                        request.setAttribute("WarningActionMessages", warningsContainer.getRequestMessages());
                        request.setAttribute("WarningPropertyList", warningsContainer.getMessagePropertyList());
                }
                
                if (errorMap.hasInfo()) {
                        InfoContainer infoContainer = new InfoContainer(errorMap);
                        
                        request.setAttribute("InfoContainer", infoContainer);
                        request.setAttribute("InfoActionMessages", infoContainer.getRequestMessages());
                        request.setAttribute("InfoPropertyList", infoContainer.getMessagePropertyList());
                }
        }

        /**
         * Checks for messages in GlobalVariables and places list in request
         * attribute.
         */
        private void saveMessages(HttpServletRequest request) {
                if (!KNSGlobalVariables.getMessageList().isEmpty()) {
                        request.setAttribute(KRADConstants.GLOBAL_MESSAGES, KNSGlobalVariables.getMessageList().toActionMessages());
                }
        }

        /**
         * Checks for messages in GlobalVariables and places list in request
         * attribute.
         */
        private void saveAuditErrors(HttpServletRequest request) {
                if (!KNSGlobalVariables.getAuditErrorMap().isEmpty()) {
                        request.setAttribute(KNSConstants.AUDIT_ERRORS, KNSGlobalVariables.getAuditErrorMap());
                }
        }

        /**
         * A simple exception that allows us to wrap an exception that is thrown out
         * of a transaction template.
         */
        @SuppressWarnings("serial")
        private static class WrappedRuntimeException extends RuntimeException {
                public WrappedRuntimeException(Exception e) {
                        super(e);
                }
        }

        /**
         * @return the sessionDocumentService
         */
        public SessionDocumentService getSessionDocumentService() {
                if ( sessionDocumentService == null ) {
                        sessionDocumentService = KNSServiceLocator.getSessionDocumentService();
                }
                return this.sessionDocumentService;
        }

        /**
         * @return the transactionManager
         */
        public PlatformTransactionManager getTransactionManager() {
                if ( transactionManager == null ) {
                        transactionManager = KRADServiceLocatorInternal.getTransactionManager();
                }
                return this.transactionManager;
        }
        
        private ActionForm createNewActionForm(ActionMapping mapping, HttpServletRequest request) {
        String name = mapping.getName();
        FormBeanConfig config = moduleConfig.findFormBeanConfig(name);
        if (config == null) {
            log.warn("No FormBeanConfig found under '" + name + "'");
            return (null);
        }
        ActionForm instance = RequestUtils.createActionForm(config, servlet);
        if ("request".equals(mapping.getScope())) {
            request.setAttribute(mapping.getAttribute(), instance);
        } else {
            HttpSession session = request.getSession();
            session.setAttribute(mapping.getAttribute(), instance);
        }
        return instance;
        }
}