/*
   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.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  
  import javax.servlet.http.HttpSession;
  
  import net.wotonomy.foundation.NSArray;
  import net.wotonomy.foundation.NSSelector;
  import net.wotonomy.foundation.internal.Introspector;
  import net.wotonomy.foundation.internal.ValueConverter;
  
  /***
  * A pure java implementation of WODirectAction.
  * This class provides a number of services to subclasses, 
  * including access to the query parameters, the request,
  * the session, and logging and debugging facilities. 
  * A new instance of the class is created and then destroyed
  * for every request-response cycle.<br><br>
  *
  * Subclass this to implement direct actions for your 
  * application.  Subclasses would typically override the
  * constructor to initialize state based on the request,
  * and then provide additional methods that would be invoked
  * based on the value at the end of the URI.  <br><br>
  *
  * Example: "http://www/MyApp.woa/MyActions/search" would call 
  * the method named "searchAction" on the DirectAction subclass 
  * named "MyActions".  If the subclass name is omitted, a subclass 
  * named "DirectAction" is assumed to exist within the application.
  *
  * @author michael@mpowers.net
  * @author $Author: cgruber $
  * @version $Revision: 905 $
  */
  public class WODirectAction
  {
  	private WORequest request;
      WOContext context;
  
  	/***
  	* Default constructor.  This is called implicitly by 
  	* subclasses in all cases.  Package access only.
  	*/
      WODirectAction ()
      {
      	
      }
  
  	/***
  	* Request constructor.  This is the constructor used
  	* to create an action in response to a user request.
  	* Override to perform any necessary initialization in
  	* your subclass.
  	*/
      public WODirectAction (WORequest aRequest)
      {
      	this();
  	    request = aRequest;
      }
  
      /***
      * Returns the response from the component named "Main".
      */
      public WOActionResults defaultAction()
      {
          return pageWithName("Main").generateResponse();   
      }
      
  	/***
  	* Returns the WORequest object for the current request.
  	*/
      public WORequest request ()
      {
      	return request;
      }
  
  	/***
  	* Returns the existing session, or null if no session exists.
  	*/
      public WOSession existingSession ()
     {
         //FIXME: this is incorrect
     	HttpSession session = request.servletRequest().getSession();
 	    if ( session == null ) return null;
 	    WOSession wosession = new WOSession();
 	    wosession.setServletSession( session );
 	    return wosession;
     }
 
 	/***
 	* Returns the existing session if it exists.  If no session
 	* exists, returns a newly created session.  Note that if the 
 	* user client does not support session ids/cookies, this will
 	* create a new session with each request.
 	*/
     public WOSession session ()
     {
         //FIXME: this is incorrect
 	    WOSession wosession = new WOSession();
 	    wosession.setServletSession( 
 	    	request.servletRequest().getSession( true ) );
 	    return wosession;
     }
 
 	/***
 	* Returns the named WOComponent. 
 	*/
     public WOComponent pageWithName (String aString)
     {
     	return request.application().pageWithName( aString, context );
     }
 
 	/***
 	* Appends "Action" to the specified string and tries to invoke
 	* method with that name and no arguments.  Returns null if
 	* the method does not exist.  If anAction is null, "defaultAction" 
     * will be assumed.
 	*/
     public WOActionResults performActionNamed (String anAction)
     {
     	if ( anAction == null ) anAction = "default";
 	    try 
 	    {
 		    NSSelector sel = new NSSelector( anAction+"Action" );
 	    	return (WOActionResults) sel.invoke( this );
 		}
 		catch ( NoSuchMethodException exc )
 		{
 			// returns below
 		}
 		catch ( InvocationTargetException exc )
 		{
 			Throwable e = exc.getTargetException();
             exc.printStackTrace();
 			throw new RuntimeException( e.toString() );
 		}
 		catch ( Exception exc )
 		{
             exc.printStackTrace();
 			throw new RuntimeException( exc.toString() );
 		}
         WOResponse error = new WOResponse();
         error.setStatus( 404 ); // not found
         error.appendContentString(
             "Could not find method named \"" + anAction + "Action\"." );
         return error;
     }
 
 	/***
 	* Assigns the arrays of form values for the specified keys
 	* to properties on this object with matching names whose type
 	* is NSArray or is convertable from a Collection.
 	*/
     public void takeFormValueArraysForKeyArray (NSArray anArray)
     {
     	if ( anArray == null ) return;
 	    
     	Method m;
 	    Object key;
 	    Object value;
 	    java.util.Enumeration e = anArray.objectEnumerator();
 	    while ( e.hasMoreElements() )
 	    {
 	    	key = e.nextElement();
 			value = request.formValuesForKey( key.toString() );
 			try
 			{
                 // obtain setter method for this class
                 m = Introspector.getPropertyWriteMethod(
                         this.getClass(), key.toString(),
                         new Class[] { Introspector.WILD } );
                 if ( m != null )
                 {
                     // if value isn't null, try to convert it to type
                     if ( value != null )
                     {
                         Class[] paramTypes = m.getParameterTypes();
                     	if ( ! paramTypes[0].isAssignableFrom( 
 			    			value.getClass() ) )
 			    		{
 					    	//TODO: find a constructor whose parameter
 							//	is assignable from value.getClass()
 							//	and instantiate it in the place of value.
 						}
 				    }
                     // set property to value
                     m.invoke( this, new Object[] { value } );
                 }
 	    	}
 		    catch ( Exception exc )
 		    {
 		    	// show error and continue
 		    	debugString( "WODirectAction.takeFormValuesForKeyArray: " + exc );
 		    }
 		}
 	    	
     }
 
 	/***
 	* Assigns the form values for the specified keys to properties
 	* on this object with matching names.
 	*/
     public void takeFormValuesForKeyArray (NSArray anArray)
     {
     	if ( anArray == null ) return;
 	    
     	Method m;
 	    Object key;
 	    Object value;
 	    java.util.Enumeration e = anArray.objectEnumerator();
 	    while ( e.hasMoreElements() )
 	    {
 	    	key = e.nextElement();
 			value = request.formValueForKey( key.toString() );
 			try
 			{
                 // obtain setter method for this class
                 m = Introspector.getPropertyWriteMethod(
                         this.getClass(), key.toString(),
                         new Class[] { Introspector.WILD } );
                 if ( m != null )
                 {
                     // if value isn't null, try to convert it to type
                     if ( value != null )
                     {
                         Class[] paramTypes = m.getParameterTypes();
                         Object convertedValue =
                             ValueConverter.convertObjectToClass(
                                 value, paramTypes[0] );
                         if ( convertedValue != null )
                         {
                             value = convertedValue;
                         }
                     }
                     // set property to value
                     m.invoke( this, new Object[] { value } );
                 }
 	    	}
 		    catch ( Exception exc )
 		    {
 		    	// show error and continue
 		    	debugString( "WODirectAction.takeFormValuesForKeyArray: " + exc );
 		    }
 		}
 	    	
     }
 
 	/***
 	* Writes a message to the standard error stream.
 	*/
     public static void logString (String aString)
     {
     	System.err.println( aString );
     }
 
 	/***
 	* Writes a message to the standard error stream
 	* if debugging is activated.
 	*/
     public static void debugString (String aString)
     {
     	// TODO: Check to see if debugging is enabled.
     	System.err.println( aString );
     }
 }
 
 /*
  * $Log$
  * Revision 1.2  2006/02/19 01:44:02  cgruber
  * Add xmlrpc files
  * Remove jclark and replace with dom4j and javax.xml.sax stuff
  * Re-work dependencies and imports so it all compiles.
  *
  * Revision 1.1  2006/02/16 13:22:22  cgruber
  * Check in all sources in eclipse-friendly maven-enabled packages.
  *
  * Revision 1.5  2003/01/13 22:24:51  mpowers
  * Request-response cycle is working with session and page persistence.
  *
  * Revision 1.4  2003/01/09 21:16:48  mpowers
  * Bringing request-response cycle more into conformance.
  *
  * Revision 1.3  2003/01/07 15:58:11  mpowers
  * Implementing the request-response cycle.
  * WOSession refactored to support distribution.
  *
  * Revision 1.2  2002/12/17 14:57:43  mpowers
  * Minor corrections to WORequests's parsing, and updated javadocs.
  *
  * Revision 1.1.1.1  2000/12/21 15:53:18  mpowers
  * Contributing wotonomy.
  *
  * Revision 1.2  2000/12/20 16:25:50  michael
  * Added log to all files.
  *
  *
  */