/*
 * @(#)$Id: AttributeWildcard.java,v 1.1 2001/10/10 23:19:12 Bear Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.grammar.xmlschema;

import com.sun.msv.grammar.*;
import java.util.Iterator;

/**
 * Attribute wildcard property of the schema component.
 * 
 * <p>
 * This object is used during the parsing process to keep the intermediate information.
 * Once the parsing is finished, attribute wildcard is kept as an expression.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@sun.com">Kohsuke KAWAGUCHI</a>
 */
public class AttributeWildcard {
	
	public AttributeWildcard( NameClass name, int processMode ) {
		this.name = name;
		this.processMode = processMode;
	}
	
	private NameClass name;
	
	/** Gets the target of the name class. */
	public NameClass getName() { return name; }
	
	private int processMode;
	
	/** Gets the processing model of the wildcard. */
	public int getProcessMode() { return processMode; }
	
	public static final int SKIP	= 0;
	public static final int LAX		= 1;
	public static final int STRICT	= 2;
	
	public AttributeWildcard copy() {
		return new AttributeWildcard(name,processMode);
	}
	
	/**
	 * Creates the expression that corresponds to
	 * the current attribute wildcard specification.
	 */
	public Expression createExpression( XMLSchemaGrammar grammar ) {
		final ExpressionPool pool = grammar.pool;
		
		switch(processMode) {
		case SKIP:
			return pool.createZeroOrMore(pool.createAttribute(name));
			
		case STRICT:
		case LAX:
			
			Expression exp = Expression.epsilon;
			LaxDefaultNameClass laxNc = new LaxDefaultNameClass(name);
			
			Iterator itr = grammar.iterateSchemas();
			while( itr.hasNext() ) {
				XMLSchemaSchema schema = (XMLSchemaSchema)itr.next();
				// nc is built by using NamespaceNameClass.
				// "strict" allows global element declarations of 
				// specified namespaces.
				if(name.accepts( schema.targetNamespace, name.LOCALNAME_WILDCARD )) {
					
					// gather global attributes.
					ReferenceExp[] atts = schema.attributeDecls.getAll();
					for( int i=0; i<atts.length; i++ ) {
						exp = pool.createSequence( pool.createOptional(atts[i]), exp );
						laxNc.addName( schema.targetNamespace, atts[i].name );
					}
				}
			}
				
			if( processMode==STRICT )
				// if processContents="strict", then that's it.
				return exp;
				
			// if "lax", we have to add an expression to
			// match other attributes.
			return pool.createSequence(
				pool.createZeroOrMore(pool.createAttribute(laxNc)), exp );
		
		default:
			throw new Error("undefined process mode:"+processMode);
		}
	}
}