/*

 Wotonomy: OpenStep design patterns for pure Java applications.

 Copyright (C) 2000 Blacksmith, Inc.

 This library is free software; you can redistribute it and/or

 modify it under the terms of the GNU Lesser General Public

 License as published by the Free Software Foundation; either

 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,

 but WITHOUT ANY WARRANTY; without even the implied warranty of

 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public

 License along with this library; if not, see http://www.gnu.org

 */

 package net.wotonomy.web;

 import java.text.SimpleDateFormat;

 import java.util.Date;

 import java.util.TimeZone;

 import net.wotonomy.foundation.NSArray;

 /**

 * A pure java implementation of WOResponse.

 *

 * @author michael@mpowers.net

 * @author $Author: cgruber $

 * @version $Revision: 905 $

 */

 public class WOResponse extends WOMessage

     implements WOActionResults

 {

         protected static String defaultEncoding;

     private static SimpleDateFormat htmlDateFormat;

     static

     {

         defaultEncoding = "ISO8859_1";

         htmlDateFormat = new SimpleDateFormat(

             "EEE, dd MMM yyyy HH:mm:ss z" );

         htmlDateFormat.setTimeZone(

             TimeZone.getTimeZone( "GMT" ) );

     }

         private int status;

         /**

         * Parameterless constructor which should not be called.

         */

     public WOResponse ()

     {

                 status = -1; // -1 indicates not yet set

     }

         /**

         * Sets the status code of the response.

         * You should use the constants defined in HttpServletResponse.

         */

     public void setStatus (int code)

     {

             status = code;

     }

         /**

         * Gets the current status code for the response.

         */

     public int status ()

     {

             return status;

     }

         /**

         * Sets a header in the response to disable client caching.

         * (Whether this works depends on the client implementation.)

         */

     public void disableClientCaching ()

     {

         String dateString = htmlDateFormat.format( new Date() );

         setHeader( dateString, "Date" );

         setHeader( dateString, "Expires" );

         setHeader( "no-cache", "Pragma" );

         setHeaders( new NSArray( new Object[] { 

             "private", "no-cache", "max-age = 0" } ), "Cache-Control" );

         //System.out.println( "disableClientCaching: " + dateString );        

     }

     /**

     * Returns this object.  (Implements the WOActionResults interface.)

     */

     public WOResponse generateResponse()

     {

             return this;

     }

         /**

         * Generates the response using the specified servlet response,

         * but does not flush the buffer. The caller is responsible

         * for sending the response to the client.  <br><br>

         * Note that this method is currently responsible for setting 

         * the content type to "text/html".  As far as I can tell, WORequests

         * have no way to set the content type and therefore must always

         * be of type "text/html".

         */

     void generateServletResponse 

             (javax.servlet.http.HttpServletResponse response)

     {

         if ( WOApplication.application().isPageRefreshOnBacktrackEnabled() )

         {

             disableClientCaching();

         }

             String key;

             java.util.Enumeration e, f;

             // set content type: might be overwritten by headers below

         response.setContentType( "text/html" );

             // set status

             if ( status != -1 )

             {

                     response.setStatus( status );            

                 }

             // set headers

             f = _headers.allKeys().objectEnumerator();

                 while ( f.hasMoreElements() )

                 {

             key = f.nextElement().toString();

                     e = ((NSArray)_headers.objectForKey( key )).objectEnumerator();

                     if ( e.hasMoreElements() )

             {

                 // overwrite existing header

                 response.setHeader( key, e.nextElement().toString() );

             }

             while ( e.hasMoreElements() )

             {

                 response.addHeader( key, e.nextElement().toString() );

             }

                 }

             // set cookies

             e = _cookies.allValues().objectEnumerator();

             while ( e.hasMoreElements() )

             {

                     response.addCookie( (WOCookie) e.nextElement() );

             }

                 try

                 {

             // write content

             response.getOutputStream().write(_contentData.bytes() );

             if ( status > 299 )

             {

                 response.sendError( status );

             }

             }

             catch ( Exception exc )

                 {

                         throw new RuntimeException( 

                                 "Error writing response: " + exc );               

                 }

     }

         /**

         * Returns the current default encoding seting.

         */

     public static String defaultEncoding ()

     {

             return defaultEncoding;

     }

         /**

         * Sets the default encoding setting.

         */

     public static void setDefaultEncoding (String encoding)

     {

             defaultEncoding = encoding;

     }

 }