/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache 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.apache.org/licenses/LICENSE-2.0
 * 
 * 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.apache.webapp.admin.host;

import java.util.Locale;
import java.util.List;
import java.io.IOException;
import javax.management.MBeanServer;
import javax.management.ObjectName;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
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.ActionMessage;
import org.apache.struts.action.ActionMessages;
import org.apache.struts.util.MessageResources;
import org.apache.webapp.admin.ApplicationServlet;

/**
 * The <code>Action</code> that completes <em>Add Alias</em> and
 * <em>Edit Alias</em> transactions.
 *
 * @author Manveen Kaur
 * @version $Revision$ $Date$
 */

public final class SaveAliasAction extends Action {


    // ----------------------------------------------------- Instance Variables

    /**
     * Signature for the <code>createStandardAlias</code> operation.
     */
    private String createStandardAliasTypes[] =
    { "java.lang.String",     // host
    };

    /**
     * The MBeanServer we will be interacting with.
     */
    private MBeanServer mBServer = null;
    

    // --------------------------------------------------------- Public Methods
    
    
    /**
     * Process the specified HTTP request, and create the corresponding HTTP
     * response (or forward to another web component that will create it).
     * Return an <code>ActionForward</code> instance describing where and how
     * control should be forwarded, or <code>null</code> if the response has
     * already been completed.
     *
     * @param mapping The ActionMapping used to select this instance
     * @param actionForm The optional ActionForm bean for this request (if any)
     * @param request The HTTP request we are processing
     * @param response The HTTP response we are creating
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet exception occurs
     */
    public ActionForward execute(ActionMapping mapping,
                                 ActionForm form,
                                 HttpServletRequest request,
                                 HttpServletResponse response)
        throws IOException, ServletException {
        
        // Acquire the resources that we need
        HttpSession session = request.getSession();
        Locale locale = getLocale(request);
        MessageResources resources = getResources(request);
        
        // Acquire a reference to the MBeanServer containing our MBeans
        try {
            mBServer = ((ApplicationServlet) getServlet()).getServer();
        } catch (Throwable t) {
            throw new ServletException
            ("Cannot acquire MBeanServer reference", t);
        }
        
        // Identify the requested action
        AliasForm aform = (AliasForm) form;

        // Perform a "Create Alias" transaction (if requested)
        String operation = "addAlias";
        
        //alias to be added
        Object values[] = new String[1];
        values[0] = aform.getAliasName();

        String hostName = aform.getHostName();

        // validate if this alias already exists.
        List aliasVals = aform.getAliasVals();
        if (aliasVals.contains(values[0])) {
            ActionMessages errors = new ActionMessages();
            errors.add("aliasName",
                       new ActionMessage("error.aliasName.exists"));
            saveErrors(request, errors);
            return (new ActionForward(mapping.getInput()));
        }
        
        try {
            
            ObjectName hname = new ObjectName(hostName);
            mBServer.invoke(hname, operation, values, createStandardAliasTypes);

        } catch (Throwable t) {
            getServlet().log
            (resources.getMessage(locale, "users.error.invoke",
                                  operation), t);
            response.sendError
                (HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
                resources.getMessage(locale, "users.error.invoke",
                                     operation));
            return (null);            
        }
                        
        // Forward to the success reporting page
        session.removeAttribute(mapping.getAttribute());
        return (mapping.findForward("Save Successful"));
        
    }
    
}