/*
 * Copyright 2001-2002,2004 The Apache Software Foundation.
 * 
 * Licensed 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.io.IOException;
import java.util.Locale;
import java.util.Arrays;
import java.util.ArrayList;
import javax.servlet.ServletException;
import javax.management.MBeanServer;
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.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.util.MessageResources;
import org.apache.webapp.admin.ApplicationServlet;
import org.apache.webapp.admin.LabelValueBean;
import org.apache.webapp.admin.Lists;
import javax.management.ObjectName;

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

public class AddAliasAction extends Action {
    
    /**
     * 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);
        }
        

        // the host Name is needed to retrieve the existing aliases
        // and add new aliases to
        String hostName = request.getParameter("hostName");
        // Fill in the form values for display and editing
        AliasForm aliasFm = new AliasForm();
        session.setAttribute("aliasForm", aliasFm);
        
        // retrieve all aliases
        String operation = null;
        try {
            ObjectName hname = new ObjectName(hostName);

            operation = "findAliases";
            String aliases[] = 
                (String[]) mBServer.invoke(hname, operation, null, null);
            
            aliasFm.setAliasVals(new ArrayList(Arrays.asList(aliases)));

        } 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);            
        }
        
        aliasFm.setAliasName("");
        aliasFm.setHostName(hostName);

        // Forward to the host display page
        return (mapping.findForward("Alias"));
        
    }
        
}