/*
   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.io.BufferedReader;
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.LineNumberReader;
  import java.io.PushbackInputStream;
  import java.io.StringReader;
  import java.lang.reflect.InvocationTargetException;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.StringTokenizer;
  
  import net.wotonomy.control.EOKeyValueCodingSupport;
  import net.wotonomy.foundation.NSArray;
  import net.wotonomy.foundation.NSDictionary;
  import net.wotonomy.foundation.NSMutableDictionary;
  import net.wotonomy.foundation.NSSelector;
  
  /***
  * Pure java implementation of WOComponent.
  *
  * @author michael@mpowers.net
  * @author $Author: cgruber $
  * @version $Revision: 905 $
  */
  public class WOComponent
      extends WOElement
      implements WOActionResults,
                 net.wotonomy.control.EOKeyValueCodingAdditions,
                 net.wotonomy.control.EOKeyValueCoding
  {
  	WOElement rootElement;
      
      private static final String DIRECTORY_SUFFIX = ".wo";
      private static final String TEMPLATE_SUFFIX = ".html";
      private static final String DECLARATION_SUFFIX = ".wod";
  
      private static final String OPEN_TAG = "webobject";
      private static final String CLOSE_TAG = "/webobject";
      private static final String NAME_KEY = "name";
      
      protected transient WOContext context; // don't persist
      protected boolean cachingEnabled;
      protected WOElement template;
      protected WOComponent parent;
  
  	/***
  	* Default constructor.  Deprecated in latest spec.
  	*/
      public WOComponent ()
      {
          parent = null;
      	cachingEnabled = true;
          template = null;
      }
      
      /***
      * Constructor specifying a context.
      */
      public WOComponent( WOContext aContext )
      {
          this();
          context = aContext;
      }
      
  	/***
  	* Returns the name of the component, which is usually just the class name.
  	*/
      public String name ()
      {
      	return justTheClassName();
      }
      
      /*** 
     * Returns the system-dependent file path to the current component
     * directory, including the ".wo" extension.
     */
     public String path ()
     {
     	throw new RuntimeException( "Not implemented yet." );
     }
 
 	/***
 	* Returns the URL for this component, relative to the server's
 	* document root on the server's file system. 
     * This is not an http url.
 	*/
     public String baseURL ()
     {
     	throw new RuntimeException( "Not implemented yet." );
     }
 
 	/***
 	* Returns the name of the framework that contains this component,
 	* or null if the component does not belong to a framework.
 	* This currently returns the package path of the class, or
 	* null if it does not belong to a package.
 	*/
     public String frameworkName ()
     {
         return justTheResourcePath();
     }
     
     /***
     * Sets whether templates are cached.  If true, templates will
     * only be read once per application lifetime.  Otherwise, templates
     * will be read each time this class is instantiated.  Defaults to false.
     */
     public void setCachingEnabled (boolean enabled)
 	{
 		cachingEnabled = enabled;
 	}
 
     /***
     * Returns whether templates are cached.  If true, templates are
     * read once per application lifetime.  Otherwise, templates are
     * read each time this class is instantiated.
     */
     public boolean isCachingEnabled ()
     {
     	return cachingEnabled && WOApplication.application().isCachingEnabled();
     }
     
     /***
     * Returns the root of the tree of elements produced by parsing
     * the templates in the component directory for this component.
     */
     public WOElement template()
     {
         return template;
     }
     
     /***
     * Returns the root of the tree of elements produced by parsing
     * the templates in the component directory for the named component.
     * @deprecated Use template() instead.
     */
     public WOElement templateWithName(String aComponentName)
     {
         return templateWithName( aComponentName, null );
     }
     
     /***
     * Returns the root of the tree of elements produced by parsing
     * the templates in the component directory for the named component.
     */
     WOElement templateWithName(String aComponentName, String aFramework)
     {
         NSArray languages = null;
         WOContext context = context();
         if ( context != null )
         {
             languages = context.request().browserLanguages();
         }
         WOElement result = templateWithHTMLString( 
             readTemplateResource( aComponentName, aFramework, TEMPLATE_SUFFIX, languages ), 
             readTemplateResource( aComponentName, aFramework, DECLARATION_SUFFIX, languages ), 
             languages );
         if ( result == null )
         {
             System.out.println( "WOComponent.templateWithName: failed for " + aComponentName );
         }
         return result;
     }
 
     /***
     * Returns the root of the tree of elements produced by parsing
     * the specfified HTML string and bindings declaration string.
     * Note: language list is currently ignored.
     */
     public static WOElement templateWithHTMLString (
     	String anHTMLString, String aDeclaration, List aLanguageList)
     {
         if ( anHTMLString == null ) return null;
         WOElement result = null;
         try
         {
 			NSDictionary bindings = processDeclaration( aDeclaration );
             List elements = new LinkedList();
             int index = processTemplate( elements, anHTMLString, 0, bindings, aLanguageList );
             if ( index == -1 )
             {
                 if ( elements.size() == 1 )
                 {
                     result = (WOElement) elements.get(0);
                 }
                 else
                 {
                     result = new WOParentElement( elements );
                 }
             }
             else // entire template did not process
             {
                 throw new RuntimeException( "No closing tag: " + anHTMLString.substring( index ) );
             }
         }
         catch ( Exception exc )
         {
             exc.printStackTrace();
         }
 		return result;
     }
     
     /***
     * Called at the beginning of a request-response cycle.
     * Override to perform any necessary initialization.
     * This implementation does nothing.
     */
     public void awake ()
     {
     }
 
     /***
     * Package access only.  Called to initialize the component with 
     * the proper context before the start of the request-response cycle.
     * If the context has a current component, that component becomes
     * this component's parent.
     */
     void ensureAwakeInContext (WOContext aContext)
     {
 		context = aContext;
 		parent = aContext.parent();
         if ( template == null )
         {
 	        template = templateWithName( name(), frameworkName() );
         }
         if ( template != null )
         {
             template.ensureAwakeInContext( aContext );
         }
         awake();
     }
 
     public void takeValuesFromRequest (WORequest aRequest, WOContext aContext)
     {
         if ( synchronizesVariablesWithBindings() )
         {
             pullValuesFromParent();
             if ( template != null )
             {
                 template.takeValuesFromRequest( aRequest, aContext ); 
             }
             pushValuesToParent();
         }
         else
         if ( template != null )
         {
             template.takeValuesFromRequest( aRequest, aContext ); 
         }
     }
 
     public WOActionResults invokeAction (WORequest aRequest, WOContext aContext)
     {
     	WOActionResults result = null;
         if ( synchronizesVariablesWithBindings() )
         {
             pullValuesFromParent();
             if ( template != null )
             {
                 result = template.invokeAction( aRequest, aContext ); 
             }
             pushValuesToParent();
         }
         else
         if ( template != null )
         {
             result = template.invokeAction( aRequest, aContext ); 
         }
 		return result;
     }
 
     public void appendToResponse (WOResponse aResponse, WOContext aContext)
     {
         if ( synchronizesVariablesWithBindings() )
         {
             pullValuesFromParent();
             if ( template != null )
             {
                 template.appendToResponse( aResponse, aContext ); 
             }
             pushValuesToParent();
         }
         else
         if ( template != null )
         {
             template.appendToResponse( aResponse, aContext ); 
         }
         context = null;
     }
 
     /***
     * Called at the end of a request-response cycle.
     * Override to perform any necessary clean-up.
     * This implementation does nothing.
     */
     public void sleep ()
     {
     }
     
     /***
     * Generates a WOResponse and calls appendToResponse() on it.
     */
     public WOResponse generateResponse ()
     {
     	WOResponse response = new WOResponse();
         WOContext context = context();
         appendToResponse( response, context ); // nulls out context
         context.session().savePage( this ); //?is this the right place for this?
         return response;
     }
 
 	/***
 	* Returns this component's parent component, or null if none.
 	*/    
     public WOComponent parent()
     {
     	return parent;
     }
 
     /***
     * Invokes the specified action on this component's parent.
     * Variables will be synchronized when this method returns.
     */
     public WOActionResults performParentAction(String anAction)
     {
         WOActionResults result = parent().performAction( anAction );
         if ( synchronizesVariablesWithBindings() )
         {
             pullValuesFromParent();
         }
         return result;
     }
     
     /***
     * Invokes the specified action on this component.
     */
     WOActionResults performAction( String anAction )
     {
 	    try 
 	    {
 	    	return (WOActionResults) NSSelector.invoke( anAction, this );
 		}
 		catch ( NoSuchMethodException exc )
 		{
 			// returns below
 		}
 		catch ( InvocationTargetException exc )
 		{
 			Throwable t = exc.getTargetException();
             exc.printStackTrace();
 			throw new RuntimeException( t.toString() );
 		}
 		catch ( Exception exc )
 		{
             exc.printStackTrace();
 			throw new RuntimeException( exc.toString() );
 		}
         return null;
     }
 
     /***
     * Called before each phase of the request-response cycle,
     * if synchronizesVariablesWithBindings is true and the 
     * component is not stateless.
     */
     public void pullValuesFromParent()
     {
         if ( associations == null ) return;
         String key;
         Enumeration e = associations.keyEnumerator();
         while ( e.hasMoreElements() )
         {
             key = e.nextElement().toString();
             takeValueForKey( valueForBinding( key ), key );
         }
     }
     
     /***
     * Called after each phase of the request-response cycle,
     * if synchronizesVariablesWithBindings is true and the 
     * component is not stateless.
     */
     public void pushValuesToParent()
     {
         if ( associations == null ) return;
         String key;
         Enumeration e = associations.keyEnumerator();
         while ( e.hasMoreElements() )
         {
             key = e.nextElement().toString();
             setValueForBinding( valueForKey( key ), key );
         }
     }
     
     /***
     * Returns whether this component should be considered stateless.
     * Stateless components are shared between sessions to conserve memory.
     * This implementation returns false; override to return true.
     */
     public boolean isStateless()
     {
         return false;
     }
     
     /***
     * Called only on stateless components to tell themselves to reset
     * themselves for another invocation using a different context.
     * This implementation does nothing.
     */
     public void reset()    
     {
         // does nothing
     }
     
     /***
     * Returns the application containing this instance of the class. 
     */ 
     public WOApplication application ()
     {
     	return context.application();
     }
     
     /***
     * Returns whether a session has been created for this user.
     */
     public boolean hasSession ()
     {
     	return context.hasSession();
     }
 
     /***
     * Returns the current session object, creating it if it doesn't exist.
     */
     public WOSession session ()
     {
     	return context.session();
     }
 
 	/***
 	* Returns the current context for this component.
 	*/
     public WOContext context ()
     {
     	return context;
     }
 
 	/***
 	* Returns a new WOComponent with the specified name.
 	* If null, returns the component named "Main".
 	* If the named component doesn't exist, returns null.
 	*/ 
     public WOComponent pageWithName (String aName)
     {
     	return application().pageWithName( aName, context() );
     }
 
 	/***
 	* Called when exceptions are raised by assigning values 
 	* to this object.  This implementation does nothing, but 
 	* subclasses may override to do something useful.
 	*/
     public void validationFailedWithException (
     	Throwable anException, Object aValue, String aPath)
     {
         // does nothing
     }
 
 	/***
 	* Called on the component that represents the requested page.
 	* Override to return logging information specific to your 
 	* component.  This implementation returns the component's name.
 	*/ 
     public String descriptionForResponse (
     	WOResponse aResponse, WOContext aContext)
     {
     	return name();
     }
 
 	/***
 	* Returns true if this component should get and set values
 	* in its parent.  This implementation returns true.
 	* Override to create a component that does not automatically
     * synchronize bindings with its parent, useful if you wish
     * to handle synchronization manually.
 	*/
     public boolean synchronizesVariablesWithBindings ()
     {
     	return true;
     }
 
     /***
     * Returns whether this component has a readable value that maps
     * to the specified binding.  This implementation calls 
     * hasBinding(aBinding).
     */
     public boolean canGetValueForBinding(String aBinding)
     {
         return hasBinding( aBinding );
     }
     
     /***
     * Returns whether this component has a writable value that maps
     * to the specified binding.  
     */
     public boolean canSetValueForBinding(String aBinding)
     {
         WOAssociation assoc = 
             (WOAssociation)associations.objectForKey(aBinding);
         if (assoc != null) 
         {
             if ( assoc.isValueSettable() ) return true;
         }
         return false;
     }
 
 	/*** 
 	* Returns whether this component has the specified binding.
 	*/
     public boolean hasBinding (String aBinding)
     {
         if ( associations == null ) return false;
     	return associations.containsKey( aBinding );
     }
 
 	/***
 	* Returns the value for the specified binding for this component.
 	* The parent component is expected to have set the binding for 
 	* this component. If no such binding exists, the binding is 
 	* treated as a property is and obtained using valueForKey.
 	* If the property is not found, this method returns null.
 	*/
     public Object valueForBinding (String aBinding)
     {
         WOComponent parent = parent();
         if ( associations != null )
         {
             WOAssociation assoc = 
                 (WOAssociation)associations.objectForKey(aBinding);
             if (assoc != null && parent != null) 
             {
                 return assoc.valueInComponent( parent );
             }
         }
         if ( parent != null )
         {
             return parent.valueForKey( aBinding );
         }
         return null;
    }
 
 	/***
 	* Sets the value for the specified binding for this component.
 	* The parent component is expected to have set the binding
 	* for this component.  If no such binding exists, the binding
 	* is treated as a property and is set using takeValueForKey.
 	* If the property is not found, this method fails silently.
 	*/
     public void setValueForBinding (Object aValue, String aBinding)
     {
         if ( associations == null ) return;
         
         WOComponent parent = parent();
 
         if ( associations != null )
         {
             WOAssociation assoc = 
                 (WOAssociation)associations.objectForKey(aBinding);
             if (assoc != null && parent != null) 
             {
                 if ( assoc.isValueSettable() )
                 {
                     assoc.setValue( aValue, parent );
                     return;
                 }
             }
         }
         if ( parent != null )
         {
             parent.takeValueForKey( aValue, aBinding );
         }
     }
  
     public static void logString (String aString)
     {
     	System.out.println( aString );
     }
 
     public static void debugString (String aString)
     {
     	System.err.println( aString );
     }
 
     public Object valueForKeyPath (String aPath)
     {
         // currently key value coding support also handles keypaths
     	return valueForKey( aPath );
     }
 
     public void takeValueForKeyPath (Object aValue, String aPath)
     {
         // currently key value coding support also handles keypaths
     	takeValueForKey( aValue, aPath );
     }
 
     public NSDictionary valuesForKeys (List aKeyList)
     {
     	throw new RuntimeException( "Not implemented yet." );
     }
 
     public void takeValuesFromDictionary (Map aValueMap)
     {
     	throw new RuntimeException( "Not implemented yet." );
     }
 
     public Object valueForKey (String aKey)
     { // System.out.println( "valueForKey: " + aKey + "->" + this );      
         // handle "^" property keys
         if ( aKey.startsWith( "^" ) )
         {
             return valueForBinding( aKey.substring(1) );
         }
     	return EOKeyValueCodingSupport.valueForKey( this, aKey );
     }
 
     public void takeValueForKey (Object aValue, String aKey)
     { // System.out.println( "takeValueForKey: " + aKey + " : " + aValue + "->" + this );      
         // handle "^" property keys
         if ( aKey.startsWith( "^" ) )
         {
             setValueForBinding( aValue, aKey.substring(1) );
             return;
         }
     	EOKeyValueCodingSupport.takeValueForKey( this, aValue, aKey );
     }
 
     public Object storedValueForKey (String aKey)
     {
     	return EOKeyValueCodingSupport.storedValueForKey( this, aKey );
     }
 
     public void takeStoredValueForKey (Object aValue, String aKey)
     {
     	EOKeyValueCodingSupport.takeStoredValueForKey( this, aValue, aKey );
     }
 
     public Object handleQueryWithUnboundKey (String aKey)
     {
     	return EOKeyValueCodingSupport.handleQueryWithUnboundKey( this, aKey );
     }
 
     public void handleTakeValueForUnboundKey (Object aValue, String aKey)
     {
     	EOKeyValueCodingSupport.handleTakeValueForUnboundKey( this, aValue, aKey );
     }
 
     public void unableToSetNullForKey (String aKey)
     {
     	EOKeyValueCodingSupport.unableToSetNullForKey( this, aKey );
     }
 
     public Object validateTakeValueForKeyPath (Object aValue, String aKey)
     {
     	throw new RuntimeException( "Not implemented yet." );
     }
 
 
 	// Template Processing
 
     /***
     * Takes a template string and a location to begin parsing,
     * looking only for interesting tags, and calling itself recursively
     * as necessary.  Returns the index to resume parsing, or -1 if done.
     */
     static private int processTemplate(
         List elements, String template, int index, 
 		Map bindings, List aLanguageList )
     	throws java.io.IOException
     { //System.out.println( "processTemplate: " + index );
     	if ( template == null ) return -1;
         
         int start = index;
         
         while ( true )
         {
             // search for start of next tag
             start = template.indexOf( '<', start );
     
             if ( start == -1 )
             {
                 // if no tags, send output and return
                 elements.add( new WOStaticElement( template.substring( index ) ) );
                 return -1;
             }
             
             // search for end of opening tag
             int end = template.indexOf( ">", start + 1 );
             if ( end == -1 )
             {
                 // if no end to tag
                 throw new RuntimeException( "No end to tag: "
                     + template.substring( start ) );
             }
     
             boolean hasBody = true;	
             if ( template.charAt( end - 1 ) == '/' )
             {
                 // tag is standalone - no body
                 end = end - 1;
                 hasBody = false;
             }
             
             // search for name of tag
             int endName = start + 1;
             while ( endName < end ) 
             {
                 if ( Character.isWhitespace( 
                     template.charAt(endName) ) ) break;
                 endName++;
             }
             
             String name = template.substring( start + 1, endName );
     
             if ( name.toLowerCase().startsWith( OPEN_TAG ) )
             {
                 // add the contents before the tag
                 //System.out.println( index + " : " + start + " : " + hasBody );                
                 elements.add( new WOStaticElement( template.substring( index, start ) ) );
     
                 // interesting tag; parse parameters
                 Map params = new HashMap( 5 ); // arbitrary init length			
                 if ( endName < end )
                 {
                     // delimit by whitespace
                     StringTokenizer tokens = new StringTokenizer(
                         template.substring( endName+1, end ) );
                     int equals;
                     String token;
                     String value;
                     while ( tokens.hasMoreTokens() )
                     {
                         token = tokens.nextToken();
                         equals = token.indexOf( '=' );
                         if ( equals != -1 )
                         {
                             value = token.substring( equals+1 );
     
                             if ( value.startsWith( "\"" ) )
                             {
                                 // handle spaces within parameter names
                                 while ( ! value.endsWith( "\"" ) ) 
                                 { 
                                     value = value + " " + tokens.nextToken();   
                                 }
     
                                 // strip quotation marks
                                 if ( value.endsWith( "\"" ) )
                                 {
                                     value = value.substring( 1, value.length()-1 );
                                 }
                             }
     
                             // register key with specified value
                             params.put( 
                                 token.substring( 0, equals ).toLowerCase(), value );
                                 
                         }
                         else
                         {
                             // no value found, register the key name
                             params.put( token.toLowerCase(), "" );
                         }
                     }
                 }
             
                 index = end + (hasBody?1:2);
                 
                 WOElement body = null;
                 if ( hasBody )
                 {
                     List childElements = new LinkedList();
                     
                     index = processTemplate( 
                         childElements, template, index, 
                         bindings, aLanguageList );
                     start = index;
                         
                     if ( index == -1 )
                     {
                         throw new RuntimeException( 
                             "No closing tag found: " + template.substring( end ) );
                     }
                     
                     if ( childElements.size() == 1 )
                     {
                         body = (WOElement) childElements.get(0);
                     }
                     else
                     {
                         body = new WOParentElement( childElements );
                     }
                 }
                 
                 WOElement element = null;
                 String nameProperty = (String) params.get( NAME_KEY );
                 NSDictionary original = (NSDictionary) bindings.get( nameProperty );
                 //System.out.println( nameProperty + " : " + associations );                
                 if ( original == null ) 
                 {
                     original = NSDictionary.EmptyDictionary;
                     System.err.println( "No associations for: " + nameProperty );
                     System.err.println( bindings );
                 }
                 
                 NSDictionary associations = new NSMutableDictionary( original );
                 String elementClass = (String) associations.remove( WOApplication.ELEMENT_CLASS );
             
                 WOApplication application = WOApplication.application();
                 element = application.dynamicElementWithName(
                     elementClass, associations, body, aLanguageList );
                 if ( element == null )
                 {
                     // unable to create element: show assocs in static element
                     element = new WOStaticElement( associations.toString() );
                 }
 
                 //System.out.println( element );                
                 elements.add( element );
                 
                 if ( !hasBody )
                 {
                     start = end + 2;
                 }
             }
             else
             if ( name.toLowerCase().startsWith( CLOSE_TAG ) )
             {
                 // add any contents before the tag
                 elements.add( new WOStaticElement( template.substring( index, start ) ) );
     
 //                return end + name.length() + 1; // "<" + ">" - 1 = 1
                 return end + (hasBody?1:2); // "<" + ">" - 1 = 1
             }
             else
             {
                 // tag not interesting: continue
                 start = end + (hasBody?1:2);
             }
         }
     }
 
 
     // Utility Methods
     
     static private void rewriteTag( String tagName, 
     	Map properties, String body, StringBuffer context )
     	throws java.io.IOException
 	{
 		context.append( "<"+tagName );
 		Iterator it = properties.keySet().iterator();
 		String key;
 		while ( it.hasNext() )
 		{
 			key = (String) it.next();
 	    	context.append( " " + key + "=\"" + properties.get( key ) + "\"" );
 		}
 		
 		if ( body == null )
 		{
 			context.append( "/>" );
 			return;
 		}
 		
 		context.append( ">" + body + "</" + tagName + ">" );
 	}
 	
     private String justTheClassName()
     {
     	String className = getClass().getName();
 	    int index = className.lastIndexOf( "." );
 	    if ( index == -1 ) return className;
 	    return className.substring( index+1 );
     }
 
     private String justTheResourcePath()
     {
         int last = -1;
         char[] src = getClass().getName().toCharArray();
         char[] dst = new char[ src.length ];
         for ( int i = 0; i < src.length; i++ )
         {
             if ( src[i] == '.' )
             {
                 dst[i] = '/';
                 last = i;
             }
             else
             {
                 dst[i] = src[i];
             }
         }
         if ( last == -1 ) return null;
         return new String( dst, 0, last );
     }
 
     private String readTemplateResource( String name, String framework, String suffix, NSArray languages )
     {
         if ( name == null ) return null;
         name = name + DIRECTORY_SUFFIX + '/' + name + suffix;
         InputStream is = null;
         if ( isCachingEnabled() )
         {
             byte[] data = WOApplication.application().resourceManager().bytesForResourceNamed( 
                 name, framework, languages );
             if ( data != null )
             {
                 is = new ByteArrayInputStream( data );
             }
         }
         else
         {
             is = WOApplication.application().resourceManager().inputStreamForResourceNamed( 
                 name, framework, languages );
         }
         if ( is == null ) 
         {
             System.err.println( "No resources found for: " + name );            
             return null;
         }
         
         // try to autodetect encoding
         String encoding = "ISO8859_1";
         try
         {
             byte[] header = new byte[4];
             is = new PushbackInputStream( is, 4 );
             is.read( header );
             if ( header[0] < 33 || header[0] > 126 ) 
             {
                 // if any funny characters, presume UTF-16
                 encoding = "UTF-16";
                 if (!( header[1] < 33 || header[1] > 126 ))
                 {
                     // if second character is valid, presume UTF-8
                     encoding = "UTF-8";
                 }
             }
             // check byte-order-mark
             if (header[0] == 0xef && header[1] == 0xbb && header[2] == 0xbf) // utf-8
             {
                 encoding = "UTF-8";
             }
             else
             if (header[0] == 0xfe && header[1] == 0xff) // utf-16
             {
                 encoding = "UTF-16";
             }
             else
             if (header[0] == 0 && header[1] == 0 && header[2] == 0xfe && header[3] == 0xff) // ucs-4
             {
                 encoding = "UCS-4"; //??
             }                
             else
             if (header[0] == 0xff && header[1] == 0xfe) // ucs-2le, ucs-4le, and 
             {
                 encoding = "UCS-16le"; //??
             }
             // put back the header
             ((PushbackInputStream)is).unread( header );
         }
         catch ( Throwable t )
         {
             t.printStackTrace();
             System.err.println( 
                 "Error while autodetecting encoding: should never happen" );
         }
 
         try
         {
             String line;
             StringBuffer buf = new StringBuffer();
             BufferedReader r = new BufferedReader( new InputStreamReader( is, encoding ) );
             while ( ( line = r.readLine() ) != null )
             {
                 buf.append( line );
                 buf.append( '\n' );
             }
             is.close(); // release the resource
             return buf.toString();
         }
         catch ( IOException exc )
         {
             System.err.println( "Error while reading: " + name );            
             exc.printStackTrace();
             return null;
         }
     }
     
     // Declaration Parsing
 
     /***
     * Parses the declarations in the specified content and returns a map of element names 
     * to maps of attribute names to WOAssociations.
     */
     private static NSDictionary processDeclaration( String content )
     {
 	    int index;
     	NSMutableDictionary result = new NSMutableDictionary();
 	    
 	    // strip out comments
 	    StringBuffer stripped = new StringBuffer();
 	    try
 	    {
             LineNumberReader reader = 
 	    		new LineNumberReader( new StringReader( content ) );
             String line;
             while ( ( line = reader.readLine() ) != null )
             {
                 index = line.indexOf("//");
                 while (index > -1) {
                     //(chochos) This used to truncate lines with quoted URLs
                     //in them. We have to check that the "//" is not inside quotes.
                     boolean quoted = false;
                     if (index > 0) {
                         for (int _position = 0; _position < index; _position++)
                             if (line.charAt(_position) == '"')
                                 quoted = !quoted;
                     }
                     if (!quoted) {
                         line = line.substring( 0, index );
                         index = -1;
                     } else {
                         //if we didn't truncate the line it's because the //
                         //were quoted. let's look for more, and check if they're not quoted...
                         index = line.indexOf("\"", index);
                         if (index > 0) {
                             index = line.indexOf("//", index);
                         }
                     }
                 }
                 stripped.append( line );
             }
 		}
 		catch ( IOException exc )
 		{
 			throw new RuntimeException( 
 				"Error while stripping comments from declaration: " + stripped );
 		}
         while ( (index = stripped.toString().indexOf( "/*" )) != -1 )
         {
             int j = stripped.toString().indexOf( "*/", index+1 );
             if ( j == -1 ) break;
             stripped.delete( index, j+2 );
         }
 	    
 	    String token;
 	    StringTokenizer tokens = new StringTokenizer( stripped.toString(), "{}", true );
 	    while ( tokens.hasMoreTokens() )
 	    {
 	    	token = tokens.nextToken();
 	    
 	    	// next token is the name and class
 		    String name, cl;
 			index = token.indexOf( ":" );
 			if ( index > -1 )
 			{
 			    name = token.substring( 0, index ).trim();
 				cl = token.substring( index+1 ).trim();
 			}
 			else
 			{
                 System.err.println( "Could not parse declaration:" );                    
                 System.err.println( content );                    
 				throw new RuntimeException( 
 					"Could not parse declaration: " + token );
 			}    
 
 			// next token is the declaration for the name and class
 			if ( ! tokens.hasMoreTokens() )
 			{
                 System.err.println( "Could not find associations for declaration:" );                    
                 System.err.println( content );                    
 				throw new RuntimeException( 
 					"Could not find associations for declaration: " + name );
 			}
 			
 	    	token = tokens.nextToken();
             if ( token.equals( "{" ) ) 
             {
                 if ( !tokens.hasMoreTokens() ) throw new RuntimeException(
                     "Error parsing declaration: expected { but found: '" + token + "'" );
                 token = tokens.nextToken();
             }
             
             NSMutableDictionary associations = new NSMutableDictionary();
             
             if ( !token.equals( "}" ) ) 
             {
                 String line, key, value; 
                 StringTokenizer lines = 
                     new StringTokenizer( token, ";" );
                 while ( lines.hasMoreElements() )
                 {
                     line = lines.nextToken(); 
                     index = line.indexOf( "=" );
                     if ( index > -1 )
                     {
                         if ( line.length() == index+ 1 ) line += " ";
                         key = line.substring( 0, index ).trim();
                         value = line.substring( index+1 ).trim();
                     }
                     else
                     {
                         // not a valid key: skip
                         key = null;
                         value = null;
                     }
     
                     if ( key != null )
                     {
                         // if in quotation marks				
                         if ( ( value.startsWith( "\"" ) ) && ( value.endsWith( "\"" ) ) )
                         {
                             // it's a constant value association
                             value = value.substring( 1, value.length()-1 );
                             associations.put( key, 
                                 WOAssociation.associationWithValue( value ) );
                         }
                         else
                         if ( value.equalsIgnoreCase( "true" ) || value.equalsIgnoreCase( "false" ) )
                         {
                             //HACK: needed to be compatible with woextensions
                             // apparently true and false are allowed without quotes
                             associations.put( key, 
                                 WOAssociation.associationWithValue( value ) );
                         }
                         else
                         {
                             //HACK: needed to be compatible with woextensions:
                             // apparently a standalone integer is allowed without quotes.
                             try 
                             {
                                 Integer.parseInt( value ); // does it parse?
                                 associations.put( key, 
                                     WOAssociation.associationWithValue( value ) );
                             }
                             catch ( NumberFormatException nfe )
                             {
                                 // did not parse:
                                 // it's a key path association
                                 associations.put( key, 
                                     WOAssociation.associationWithKeyPath( value ) );
                             }
                         }
                     }
                 }
                 if ( tokens.hasMoreTokens() ) 
                 {
                     token = tokens.nextToken();
                     if ( !token.equals( "}" ) ) throw new RuntimeException( 
                         "Error parsing declaration: expected } but found: '" + token + "'" );
                 }
             }
             associations.put( WOApplication.ELEMENT_CLASS, cl ); // store classname
             result.put( name, associations );
             
 	    }
         //System.out.println( "processDeclaration: " + result );
 	    return result;
     }
 
 }
 
 /*
  * $Log$
  * 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 1.32  2003/08/07 00:15:14  chochos
  * general cleanup (mostly removing unused imports)
  *
  * Revision 1.31  2003/07/24 00:23:21  chochos
  * fixed problem with parsing wod files that have //-type comments. Quotes URL's would be truncated.
  *
  * Revision 1.30  2003/03/28 15:33:11  mpowers
  * Now using a PushBackInputStream for auto detection of content encoding.
  * No longer relying on markSupported() since jar input streams don't have it.
  *
  * Revision 1.29  2003/03/03 16:41:52  mpowers
  * Bad characters in cvs log.
  *
  * Revision 1.28  2003/03/03 16:37:35  mpowers
  * Better handling for string encodings.
  * Now trying to autodetect unicode-formatted templates and declarations.
  * Now handlings block-style comments in declarations.
  *
  * Revision 1.27  2003/01/28 19:33:51  mpowers
  * Implemented the rest of WOResourceManager.
  * Implemented support for java-style i18n.
  * Components now use the resource manager to load templates.
  *
  * Revision 1.26  2003/01/24 20:13:22  mpowers
  * Now accepting immutable NSDictionary in constructor, not Map.
  *
  * Revision 1.25  2003/01/21 17:53:45  mpowers
  * Now correctly reporting error for missing bindings.
  *
  * Revision 1.24  2003/01/20 17:50:11  mpowers
  * Caught a loop condition when same declaration was used twice.
  *
  * Revision 1.23  2003/01/19 22:33:25  mpowers
  * Fixed problems with classpath and dynamic class loading.
  * Dynamic elements now pass on ensureAwakeInContext.
  * Parser how handles <standalone/> tags.
  *
  * Revision 1.22  2003/01/17 22:55:09  mpowers
  * Straighted out the parent binding issue (I think).
  * Fixes for woextensions compatibility.
  *
  * Revision 1.21  2003/01/17 20:34:57  mpowers
  * Better handling for components and parents in the context's element stack.
  *
  * Revision 1.19  2003/01/17 15:32:22  mpowers
  * Changes to better support generic elements and containers.
  * Now preserving newlines in templates.
  *
  * Revision 1.17  2003/01/16 22:47:30  mpowers
  * Compatibility changes to support compiling woextensions source.
  * (34 out of 56 classes compile!)
  *
  * Revision 1.15  2003/01/16 15:50:43  mpowers
  * More robust declaration parsing.
  * Subcomponents are now supported.
  * dynamicElementWithName can now return subcomponents.
  *
  * Revision 1.14  2003/01/15 19:50:49  mpowers
  * Fixed issues with WOSession and Serializable.
  * Can now persist sessions between classloaders (hot swap of class impls).
  *
  * Revision 1.13  2003/01/15 14:33:48  mpowers
  * Refactoring: element id handling is now confined to WOParentElement.
  * Other elements/components should not have to do element id incrementing.
  *
  * Revision 1.12  2003/01/14 16:05:12  mpowers
  * Removed extraneous printlns.
  *
  * Revision 1.11  2003/01/13 22:24:25  mpowers
  * Request-response cycle is working with session and page persistence.
  *
  * Revision 1.10  2003/01/10 19:33:28  mpowers
  * Added contextID for the component url generation.
  *
  * Revision 1.9  2003/01/10 19:16:40  mpowers
  * Implemented support for page caching.
  *
  * Revision 1.8  2003/01/09 21:16:48  mpowers
  * Bringing request-response cycle more into conformance.
  *
  * Revision 1.7  2003/01/09 16:13:55  mpowers
  * Implemented WOComponentRequestHandler:
  * Bringing the request-response cycle more into conformance.
  *
  * Revision 1.6  2002/12/20 22:56:33  mpowers
  * Reimplemented the template parsing again.
  * Nested components are now correctly parsed.
  * ElementID numbering is now working.
  *
  * Revision 1.3  2002/12/18 14:12:38  mpowers
  * Support for differentiated request handlers.
  * Support url generation for WOContext and WORequest.
  *
  * Revision 1.2  2002/11/07 18:52:33  mpowers
  * New components courtesy of ezamudio@nasoft.com.  Many thanks!
  *
  * Revision 1.1.1.1  2000/12/21 15:53:01  mpowers
  * Contributing wotonomy.
  *
  * Revision 1.2  2000/12/20 16:25:49  michael
  * Added log to all files.
  *
  *
  */