/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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.ws.commons.schema;

import org.apache.ws.commons.schema.XmlSchemaCollection.SchemaKey;
import org.apache.ws.commons.schema.constants.Constants;
import org.apache.ws.commons.schema.extensions.ExtensionRegistry;
import org.apache.ws.commons.schema.utils.NodeNamespaceContext;
import org.apache.ws.commons.schema.utils.TargetNamespaceValidator;
import org.apache.ws.commons.schema.utils.XDOMUtil;
import org.apache.ws.commons.schema.utils.DOMUtil;
import org.w3c.dom.*;
import org.xml.sax.InputSource;

import javax.xml.namespace.NamespaceContext;
import javax.xml.namespace.QName;
import javax.xml.parsers.DocumentBuilderFactory;

import java.lang.ref.SoftReference;
import java.util.Hashtable;
import java.util.StringTokenizer;
import java.util.Vector;

public class SchemaBuilder {
	Document doc;
	XmlSchema schema;
	XmlSchemaCollection collection;
	private final TargetNamespaceValidator validator;
	DocumentBuilderFactory docFac;

	/**
	 * The extension registry to be used while building the
	 * schema model
	 */
	private ExtensionRegistry extReg = null;

	public ExtensionRegistry getExtReg() {
		return extReg;
	}

	public void setExtReg(ExtensionRegistry extReg) {
		this.extReg = extReg;
	}
    
    /*
     * cache of previously resolved schema documents.
     * 
     * This cache might be usefull when an application has multiple webservices that each have WSDL documents
     * that import the same schema, for example.  On app startup, we may wish to cache XmlSchema objects so we
     * don't build up the schema graph multiple times.
     * 
     * key - use a combination of thread id and all three parameters passed to resolveXmlSchema to give minimal thread safety*
     * value - XmlSchema object wrapped in a SoftReference to encourage GC in low memory situations
     * 
     * *CAUTION:  XmlSchema objects are not likely to be thread-safe.  This cache should
     * only be used, then cleared, by callers aware of its existence.  It is VERY important that users of this
     * cache call clearCache() after they are done.
     * 
     * Usage of the cache is controlled by calling initCache() which will initialize resolvedSchemas to non-null
     * Clearing of cache is done by calling clearCache() which will clear and nullify resolvedSchemas
     *
     */
    private static Hashtable resolvedSchemas = null;

	/**
	 * Schema builder constructor
	 * @param collection
	 */
	SchemaBuilder(XmlSchemaCollection collection,
			TargetNamespaceValidator validator) {
		this.collection = collection;
		this.validator = validator;

		if (collection.getExtReg() != null) {
			this.extReg = collection.getExtReg();
		}

		schema = new XmlSchema();
	}
    
    public static synchronized void initCache() {
        if (resolvedSchemas == null) {
            resolvedSchemas = new Hashtable();
        }
    }
    
    public static synchronized void clearCache() {
        if (resolvedSchemas != null) {
            resolvedSchemas.clear();  // necessary?
            resolvedSchemas = null;
        }
    }

	/**
	 * build method taking in a document and a validation handler
	 * @param doc
	 * @param uri
	 * @param veh
	 */
	XmlSchema build(Document doc, String uri, ValidationEventHandler veh) {
		Element schemaEl = doc.getDocumentElement();
		XmlSchema xmlSchema = handleXmlSchemaElement(schemaEl, uri);
		xmlSchema.setInputEncoding(DOMUtil.getInputEncoding(doc));
		return xmlSchema;
	}

	/**
	 * handles the schema element
	 * @param schemaEl
	 * @param uri
	 */
	XmlSchema handleXmlSchemaElement(Element schemaEl, String uri) {
		// get all the attributes along with the namespace declns
		schema.setNamespaceContext(NodeNamespaceContext.getNamespaceContext(schemaEl));
		setNamespaceAttributes(schema, schemaEl);

		XmlSchemaCollection.SchemaKey schemaKey = new XmlSchemaCollection.SchemaKey(
				schema.logicalTargetNamespace, uri);
		if (!collection.containsSchema(schemaKey)) {
			collection.addSchema(schemaKey, schema);
			schema.parent = collection; // establish parentage now.
		} else {
			throw new XmlSchemaException("Schema name conflict in collection. Namespace: " + schema.logicalTargetNamespace);
		}

		schema.setElementFormDefault(this.getFormDefault(schemaEl,
				"elementFormDefault"));
		schema.setAttributeFormDefault(this.getFormDefault(schemaEl,
				"attributeFormDefault"));
		schema.setBlockDefault(this.getDerivation(schemaEl, "blockDefault"));
		schema.setFinalDefault(this.getDerivation(schemaEl, "finalDefault"));
		/* set id attribute */
		if (schemaEl.hasAttribute("id")) {
			schema.id = schemaEl.getAttribute("id");
		}

		schema.setSourceURI(uri);

		/***********
		 * for ( each childElement)
		 *		if( simpleTypeElement)
		 *			handleSimpleType
		 *		else if( complexType)
		 *			handleComplexType
		 *		else if( element)
		 *			handleElement
		 *		else if( include)
		 *			handleInclude
		 *		else if( import)
		 *			handleImport
		 *		else if (group)
		 *			handleGroup
		 *		else if (attributeGroup)
		 *			handleattributeGroup
		 *		else if( attribute)
		 *			handleattribute
		 *		else if (redefine)
		 *			handleRedefine
		 *		else if(notation)
		 *			handleNotation
		 *      else if (annotation)
		 *          handleAnnotation
		 */

		Element el = XDOMUtil.getFirstChildElementNS(schemaEl,
				XmlSchema.SCHEMA_NS);
		if (el == null
				&& XDOMUtil.getFirstChildElementNS(schemaEl,
						"http://www.w3.org/1999/XMLSchema") != null) {
			throw new XmlSchemaException(
					"Schema defined using \"http://www.w3.org/1999/XMLSchema\" is not supported. "
							+ "Please update the schema to the \""
							+ XmlSchema.SCHEMA_NS + "\" namespace");
		}
		for (; el != null; el = XDOMUtil.getNextSiblingElementNS(el,
				XmlSchema.SCHEMA_NS)) {

			// String elPrefix = el.getPrefix() == null ? "" : el.getPrefix();
			//if(elPrefix.equals(schema.schema_ns_prefix)) {
			if (el.getLocalName().equals("simpleType")) {
				XmlSchemaType type = handleSimpleType(schema, el, schemaEl);
				schema.addType(type);
				schema.items.add(type);
				collection.resolveType(type.getQName(), type);
			} else if (el.getLocalName().equals("complexType")) {
				XmlSchemaType type = handleComplexType(schema, el, schemaEl);
				schema.addType(type);
				schema.items.add(type);
				collection.resolveType(type.getQName(), type);
			} else if (el.getLocalName().equals("element")) {
				XmlSchemaElement element = handleElement(schema, el, schemaEl,
						true);
				if (element.qualifiedName != null)
					schema.elements.collection.put(element.qualifiedName,
							element);
				else if (element.refName != null)
					schema.elements.collection.put(element.refName, element);
				schema.items.add(element);
			} else if (el.getLocalName().equals("include")) {
				XmlSchemaInclude include = handleInclude(schema, el, schemaEl);
				schema.includes.add(include);
				schema.items.add(include);

			} else if (el.getLocalName().equals("import")) {
				XmlSchemaImport schemaImport = handleImport(schema, el,
						schemaEl);
				schema.includes.add(schemaImport);
				schema.items.add(schemaImport);

			} else if (el.getLocalName().equals("group")) {
				XmlSchemaGroup group = handleGroup(schema, el, schemaEl);
				schema.groups.collection.put(group.name, group);
				schema.items.add(group);
			} else if (el.getLocalName().equals("attributeGroup")) {
				XmlSchemaAttributeGroup group = handleAttributeGroup(schema,
						el, schemaEl);
				schema.attributeGroups.collection.put(group.name, group);
				schema.items.add(group);
			} else if (el.getLocalName().equals("attribute")) {
				XmlSchemaAttribute attr = handleAttribute(schema, el, schemaEl,
						true); //pass true to indicate that it is a top level child
				schema.attributes.collection.put(attr.qualifiedName, attr);
				schema.items.add(attr);
			} else if (el.getLocalName().equals("redefine")) {
				XmlSchemaRedefine redefine = handleRedefine(schema, el,
						schemaEl);
				schema.includes.add(redefine);
			} else if (el.getLocalName().equals("notation")) {
				XmlSchemaNotation notation = handleNotation(el);
				schema.notations.collection.put(new QName(schema
						.getTargetNamespace(), notation.name), notation);
				schema.items.add(notation);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation annotation = handleAnnotation(el);
				schema.setAnnotation(annotation);
			}
		}

		//add the extesibility components
		processExtensibilityComponents(schema, schemaEl);

		return schema;
	}

	private XmlSchemaNotation handleNotation(Element notationEl) {

		XmlSchemaNotation notation = new XmlSchemaNotation();

		if (notationEl.hasAttribute("id")) {
			notation.id = notationEl.getAttribute("id");
		}

		if (notationEl.hasAttribute("name")) {
			notation.name = notationEl.getAttribute("name");
		}

		if (notationEl.hasAttribute("public")) {
			notation.publicNotation = notationEl.getAttribute("public");
		}

		if (notationEl.hasAttribute("system")) {
			notation.system = notationEl.getAttribute("system");
		}

		Element annotationEl = XDOMUtil.getFirstChildElementNS(notationEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);
			notation.setAnnotation(annotation);
		}

		return notation;
	}

	/**
	 * Handle redefine
	 * @param schema
	 * @param redefineEl
	 * @param schemaEl
	 * @return
	 */
	private XmlSchemaRedefine handleRedefine(XmlSchema schema,
			Element redefineEl, Element schemaEl) {

		XmlSchemaRedefine redefine = new XmlSchemaRedefine();
		redefine.schemaLocation = redefineEl.getAttribute("schemaLocation");
		final TargetNamespaceValidator validator = newIncludeValidator(schema);
		
		if (schema.getSourceURI() != null) {
			redefine.schema = resolveXmlSchema(schema.logicalTargetNamespace,
					redefine.schemaLocation, schema.getSourceURI(), validator);
		} else {
			redefine.schema = resolveXmlSchema(schema.logicalTargetNamespace,
					redefine.schemaLocation, validator);
		}

		/*
		 * FIXME - This seems not right. Since the redefine should take into account 
		 * the attributes of the original element we cannot just build the type
		 * defined in the redefine section - what we need to do is to get the original type
		 * object and modify it. However one may argue (quite reasonably) that the purpose
		 * of this object model is to provide just the representation and not the validation
		 * (as it has been always the case)
		 */

		for (Element el = XDOMUtil.getFirstChildElementNS(redefineEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("simpleType")) {
				XmlSchemaType type = handleSimpleType(schema, el, schemaEl);

				redefine.schemaTypes.collection.put(type.getQName(), type);
				redefine.items.add(type);
			} else if (el.getLocalName().equals("complexType")) {

				XmlSchemaType type = handleComplexType(schema, el, schemaEl);

				redefine.schemaTypes.collection.put(type.getQName(), type);
				redefine.items.add(type);
			} else if (el.getLocalName().equals("group")) {
				XmlSchemaGroup group = handleGroup(schema, el, schemaEl);
				redefine.groups.collection.put(group.name, group);
				redefine.items.add(group);
			} else if (el.getLocalName().equals("attributeGroup")) {
				XmlSchemaAttributeGroup group = handleAttributeGroup(schema,
						el, schemaEl);

				redefine.attributeGroups.collection.put(group.name, group);
				redefine.items.add(group);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation annotation = handleAnnotation(el);
				redefine.setAnnotation(annotation);
			}
			//                  }
		}
		return redefine;
	}

	void setNamespaceAttributes(XmlSchema schema, Element schemaEl) {
		//no targetnamespace found !
		if (schemaEl.getAttributeNode("targetNamespace") != null) {
			String contain = schemaEl.getAttribute("targetNamespace");
			schema.setTargetNamespace(contain);
		} else {
			//do nothing here
		}
		if (validator != null) {
			validator.validate(schema);
		}
	}

	/**
	 * Handles simple types
	 * @param schema
	 * @param simpleEl
	 * @param schemaEl
	 */
	XmlSchemaSimpleType handleSimpleType(XmlSchema schema, Element simpleEl,
			Element schemaEl) {
		XmlSchemaSimpleType simpleType = new XmlSchemaSimpleType(schema);
		if (simpleEl.hasAttribute("name")) {
			simpleType.name = simpleEl.getAttribute("name");
		}

		if (simpleEl.hasAttribute("final")) {
			String finalstr = simpleEl.getAttribute("final");

			if (finalstr.equalsIgnoreCase("all")
					| finalstr.equalsIgnoreCase("#all"))

				simpleType.setFinal(new XmlSchemaDerivationMethod(
						Constants.BlockConstants.ALL));
			else
				simpleType.setFinal(new XmlSchemaDerivationMethod(finalstr));
		}

		Element simpleTypeAnnotationEl = XDOMUtil.getFirstChildElementNS(
				simpleEl, XmlSchema.SCHEMA_NS, "annotation");

		if (simpleTypeAnnotationEl != null) {
			XmlSchemaAnnotation simpleTypeAnnotation = handleAnnotation(simpleTypeAnnotationEl);

			simpleType.setAnnotation(simpleTypeAnnotation);
		}

		Element unionEl, listEl, restrictionEl;

		if ((restrictionEl = XDOMUtil.getFirstChildElementNS(simpleEl,
				XmlSchema.SCHEMA_NS, "restriction")) != null) {

			XmlSchemaSimpleTypeRestriction restriction = new XmlSchemaSimpleTypeRestriction();

			Element restAnnotationEl = XDOMUtil.getFirstChildElementNS(
					restrictionEl, XmlSchema.SCHEMA_NS, "annotation");

			if (restAnnotationEl != null) {
				XmlSchemaAnnotation restAnnotation = handleAnnotation(restAnnotationEl);
				restriction.setAnnotation(restAnnotation);
			}
			/** if (restriction has a base attribute )
			 *		set the baseTypeName and look up the base type
			 *	else if( restricion has a SimpleType Element as child)
			 *		get that element and do a handleSimpleType;
			 *	get the children of restriction other than annotation
			 * and simpleTypes and construct facets from it;
			 *
			 *	set the restriction has the content of the simpleType
			 *
			 **/

			Element inlineSimpleType = XDOMUtil.getFirstChildElementNS(
					restrictionEl, XmlSchema.SCHEMA_NS, "simpleType");

			if (restrictionEl.hasAttribute("base")) {
				NamespaceContext ctx = NodeNamespaceContext.getNamespaceContext(restrictionEl);
				restriction.baseTypeName = getRefQName(restrictionEl
						.getAttribute("base"), ctx);
			} else if (inlineSimpleType != null) {

				restriction.baseType = handleSimpleType(schema,
						inlineSimpleType, schemaEl);
			}
			for (Element el = XDOMUtil.getFirstChildElementNS(restrictionEl,
					XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
					.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

				if (!el.getLocalName().equals("annotation")
						&& !el.getLocalName().equals("simpleType")) {

					XmlSchemaFacet facet = XmlSchemaFacet.construct(el);
					Element annotation = XDOMUtil.getFirstChildElementNS(el,
							XmlSchema.SCHEMA_NS, "annotation");

					if (annotation != null) {
						XmlSchemaAnnotation facetAnnotation = handleAnnotation(annotation);
						facet.setAnnotation(facetAnnotation);
					}
					restriction.facets.add(facet);
				}

			}
			simpleType.content = restriction;

		} else if ((listEl = XDOMUtil.getFirstChildElementNS(simpleEl,
				XmlSchema.SCHEMA_NS, "list")) != null) {

			XmlSchemaSimpleTypeList list = new XmlSchemaSimpleTypeList();

			/******
			 * if( list has an itemType attribute )
			 *		set the baseTypeName and look up the base type
			 * else if( list has a SimpleTypeElement as child)
			 *		get that element and do a handleSimpleType
			 *
			 * set the list has the content of the simpleType
			 */
			Element inlineListType, listAnnotationEl;
			if (listEl.hasAttribute("itemType")) {
				String name = listEl.getAttribute("itemType");
				list.itemTypeName = getRefQName(name, listEl);
			} else if ((inlineListType = XDOMUtil.getFirstChildElementNS(
					listEl, XmlSchema.SCHEMA_NS, "simpleType")) != null) {

				list.itemType = handleSimpleType(schema, inlineListType,
						schemaEl);
			}

			if ((listAnnotationEl = XDOMUtil.getFirstChildElementNS(listEl,
					XmlSchema.SCHEMA_NS, "annotation")) != null) {

				XmlSchemaAnnotation listAnnotation = handleAnnotation(listAnnotationEl);

				list.setAnnotation(listAnnotation);
			}
			simpleType.content = list;

		} else if ((unionEl = XDOMUtil.getFirstChildElementNS(simpleEl,
				XmlSchema.SCHEMA_NS, "union")) != null) {

			XmlSchemaSimpleTypeUnion union = new XmlSchemaSimpleTypeUnion();

			/******
			 * if( union has a memberTypes attribute )
			 *		add the memberTypeSources string
			 *		for (each memberType in the list )
			 *			lookup(memberType)
			 *	for( all SimpleType child Elements)
			 *		add the simpleTypeName (if any) to the memberType Sources
			 *		do a handleSimpleType with the simpleTypeElement
			 */
			if (unionEl.hasAttribute("memberTypes")) {
				String memberTypes = unionEl.getAttribute("memberTypes");
				union.memberTypesSource = memberTypes;
				Vector v = new Vector();
				StringTokenizer tokenizer = new StringTokenizer(memberTypes,
						" ");
				while (tokenizer.hasMoreTokens()) {
					String member = tokenizer.nextToken();
					v.add(getRefQName(member, unionEl));
				}
				union.memberTypesQNames = new QName[v.size()];
				v.copyInto(union.memberTypesQNames);
			}

			Element inlineUnionType = XDOMUtil.getFirstChildElementNS(unionEl,
					XmlSchema.SCHEMA_NS, "simpleType");
			while (inlineUnionType != null) {

				XmlSchemaSimpleType unionSimpleType = handleSimpleType(schema,
						inlineUnionType, schemaEl);

				union.baseTypes.add(unionSimpleType);

				if (unionSimpleType.name != null) {
					union.memberTypesSource += " " + unionSimpleType.name;
				}

				inlineUnionType = XDOMUtil.getNextSiblingElementNS(
						inlineUnionType, XmlSchema.SCHEMA_NS, "simpleType");
			}

			//NodeList annotations = unionEl.getElementsByTagNameNS(
			//XmlSchema.SCHEMA_NS, "annotation");
			Element unionAnnotationEl = XDOMUtil.getFirstChildElementNS(
					unionEl, XmlSchema.SCHEMA_NS, "annotation");

			if (unionAnnotationEl != null) {
				XmlSchemaAnnotation unionAnnotation = handleAnnotation(unionAnnotationEl);

				union.setAnnotation(unionAnnotation);
			}
			simpleType.content = union;
		}

		//process extra attributes and elements
		processExtensibilityComponents(simpleType, simpleEl);

		return simpleType;
	}

	private QName getRefQName(String pName, Node pNode) {
		return getRefQName(pName, NodeNamespaceContext.getNamespaceContext(pNode));
	}

	private QName getRefQName(String pName, NamespaceContext pContext) {
		final int offset = pName.indexOf(':');
		String uri;
		final String localName;
		final String prefix;
		if (offset == -1) {
			uri = pContext.getNamespaceURI(Constants.DEFAULT_NS_PREFIX);
			if (Constants.NULL_NS_URI.equals(uri)) {
				return new QName(Constants.NULL_NS_URI, pName);
			}
			localName = pName;
			prefix = Constants.DEFAULT_NS_PREFIX;
		} else {
			prefix = pName.substring(0, offset);
			uri = pContext.getNamespaceURI(prefix);
			if (uri == null || Constants.NULL_NS_URI.equals(uri)) {
				if (schema.parent != null
						&& schema.parent.getNamespaceContext() != null) {
					uri = schema.parent.getNamespaceContext().getNamespaceURI(
							prefix);
				}
			}

			if (uri == null || Constants.NULL_NS_URI.equals(uri)) {
				throw new IllegalStateException("The prefix " + prefix
						+ " is not bound.");
			}
			localName = pName.substring(offset + 1);
		}
		return new QName(uri, localName, prefix);
	}

	/**
	 * Handle complex types
	 * @param schema
	 * @param complexEl
	 * @param schemaEl
	 */
	XmlSchemaComplexType handleComplexType(XmlSchema schema, Element complexEl,
			Element schemaEl) {

		/******
		 * set the complexTypeName if any
		 * for( eachChildNode)
		 * if ( simpleContent)
		 *		if( restrcition)
		 *			handle_simple_content_restriction
		 *		else if( extension)
		 *			handle_simple_content_extension
		 *		break; // it has to be the only child
		 * else if( complexContent)
		 *		if( restriction)
		 *			handle_complex_content_restriction
		 *		else if( extension)
		 *			handle_complex_content_extension
		 *		break; // it has to be the only child
		 * else if( group)
		 *		if( group has ref)
		 *			store the group name
		 *		else
		 *			handleGroup
		 * else if( sequence )
		 *		handleSequence
		 * else if( all )
		 *		handleAll
		 * else if(choice)
		 *		handleChoice
		 * else if(attribute)
		 *		handleAttribute
		 * else if(attributeGroup)
		 *		handleAttributeGroup
		 *  else if(anyAttribute)
		 *		handleAnyAttribute
		 */

		XmlSchemaComplexType ct = new XmlSchemaComplexType(schema);

		if (complexEl.hasAttribute("name")) {

			//String namespace = (schema.targetNamespace==null)?
			//                  "":schema.targetNamespace;

			ct.name = complexEl.getAttribute("name");
		}
		for (Element el = XDOMUtil.getFirstChildElementNS(complexEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			//String elPrefix = el.getPrefix() == null ? "" :
			//el.getPrefix();
			//if(elPrefix.equals(schema.schema_ns_prefix)) {
			if (el.getLocalName().equals("sequence")) {
				ct.particle = handleSequence(schema, el, schemaEl);
			} else if (el.getLocalName().equals("choice")) {
				ct.particle = handleChoice(schema, el, schemaEl);
			} else if (el.getLocalName().equals("all")) {
				ct.particle = handleAll(schema, el, schemaEl);
			} else if (el.getLocalName().equals("attribute")) {
				ct.attributes.add(handleAttribute(schema, el, schemaEl));
			} else if (el.getLocalName().equals("attributeGroup")) {
				ct.attributes.add(handleAttributeGroupRef(el));
			} else if (el.getLocalName().equals("group")) {
				XmlSchemaGroupRef group = handleGroupRef(schema, el, schemaEl);
				ct.particle = (group.particle == null) ? (XmlSchemaParticle) group
						: group.particle;
			} else if (el.getLocalName().equals("simpleContent")) {
				ct.contentModel = handleSimpleContent(schema, el, schemaEl);
			} else if (el.getLocalName().equals("complexContent")) {
				ct.contentModel = handleComplexContent(schema, el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				ct.setAnnotation(handleAnnotation(el));
			} else if (el.getLocalName().equals("anyAttribute")) {
				ct.setAnyAttribute(handleAnyAttribute(schema, el, schemaEl));
			}
			//}
		}
		if (complexEl.hasAttribute("block")) {
			String blockStr = complexEl.getAttribute("block");
			if (blockStr.equalsIgnoreCase("all")
					| blockStr.equalsIgnoreCase("#all")) {

				ct.setBlock(new XmlSchemaDerivationMethod(
						Constants.BlockConstants.ALL));
			} else
				ct.setBlock(new XmlSchemaDerivationMethod(blockStr));
			//ct.setBlock(new XmlSchemaDerivationMethod(block));
		}
		if (complexEl.hasAttribute("final")) {
			String finalstr = complexEl.getAttribute("final");
			if (finalstr.equalsIgnoreCase("all")
					| finalstr.equalsIgnoreCase("#all")) {

				ct.setFinal(new XmlSchemaDerivationMethod(
						Constants.BlockConstants.ALL));
			} else
				ct.setFinal(new XmlSchemaDerivationMethod(finalstr));
		}
		if (complexEl.hasAttribute("abstract")) {
			String abs = complexEl.getAttribute("abstract");
			if (abs.equalsIgnoreCase("true"))
				ct.setAbstract(true);
			else
				ct.setAbstract(false);
		}
		if (complexEl.hasAttribute("mixed")) {
			String mixed = complexEl.getAttribute("mixed");
			if (mixed.equalsIgnoreCase("true"))
				ct.setMixed(true);
			else
				ct.setMixed(false);
		}

		//process extra attributes and elements
		processExtensibilityComponents(ct, complexEl);

		return ct;
	}

	private XmlSchemaSimpleContent handleSimpleContent(XmlSchema schema,
			Element simpleEl, Element schemaEl) {

		XmlSchemaSimpleContent simpleContent = new XmlSchemaSimpleContent();

		for (Element el = XDOMUtil.getFirstChildElementNS(simpleEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("restriction")) {
				simpleContent.content = handleSimpleContentRestriction(schema,
						el, schemaEl);
			} else if (el.getLocalName().equals("extension")) {
				simpleContent.content = handleSimpleContentExtension(schema,
						el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				simpleContent.setAnnotation(handleAnnotation(el));
			}
		}
		return simpleContent;
	}

	private XmlSchemaComplexContent handleComplexContent(XmlSchema schema,
			Element complexEl, Element schemaEl) {

		XmlSchemaComplexContent complexContent = new XmlSchemaComplexContent();

		for (Element el = XDOMUtil.getFirstChildElementNS(complexEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("restriction")) {
				complexContent.content = handleComplexContentRestriction(
						schema, el, schemaEl);
			} else if (el.getLocalName().equals("extension")) {
				complexContent.content = handleComplexContentExtension(schema,
						el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				complexContent.setAnnotation(handleAnnotation(el));
			}
		}
		
		if (complexEl.hasAttribute("mixed")) {
			String mixed = complexEl.getAttribute("mixed");
			if (mixed.equalsIgnoreCase("true"))
				complexContent.setMixed(true);
			else
				complexContent.setMixed(false);
		} 
		
		return complexContent;
	}

	private XmlSchemaSimpleContentRestriction handleSimpleContentRestriction(
			XmlSchema schema, Element restrictionEl, Element schemaEl) {

		XmlSchemaSimpleContentRestriction restriction = new XmlSchemaSimpleContentRestriction();

		if (restrictionEl.hasAttribute("base")) {
			String name = restrictionEl.getAttribute("base");
			restriction.baseTypeName = getRefQName(name, restrictionEl);
		}

		if (restrictionEl.hasAttribute("id"))
			restriction.id = restrictionEl.getAttribute("id");

		// check back simpleContent tag children to add attributes and simpleType if any occur
		for (Element el = XDOMUtil.getFirstChildElementNS(restrictionEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("attribute")) {
				XmlSchemaAttribute attr = handleAttribute(schema, el, schemaEl);
				restriction.attributes.add(attr);
			} else if (el.getLocalName().equals("attributeGroup")) {
				XmlSchemaAttributeGroupRef attrGroup = handleAttributeGroupRef(el);
				restriction.attributes.add(attrGroup);
			} else if (el.getLocalName().equals("simpleType")) {
				restriction.baseType = handleSimpleType(schema, el, schemaEl);
			} else if (el.getLocalName().equals("anyAttribute")) {
				restriction.anyAttribute = handleAnyAttribute(schema, el,
						schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				restriction.setAnnotation(handleAnnotation(el));
			} else {
				XmlSchemaFacet facet = XmlSchemaFacet.construct(el);
				NodeList annotations = el.getElementsByTagNameNS(
						XmlSchema.SCHEMA_NS, "annotation");

				if (annotations.getLength() > 0) {
					XmlSchemaAnnotation facetAnnotation = handleAnnotation(el);
					facet.setAnnotation(facetAnnotation);
				}
				restriction.facets.add(facet);
			}
		}
		return restriction;
	}

	private XmlSchemaSimpleContentExtension handleSimpleContentExtension(
			XmlSchema schema, Element extEl, Element schemaEl) {

		XmlSchemaSimpleContentExtension ext = new XmlSchemaSimpleContentExtension();

		if (extEl.hasAttribute("base")) {
			String name = extEl.getAttribute("base");
			ext.baseTypeName = getRefQName(name, extEl);
		}

		for (Element el = XDOMUtil.getFirstChildElementNS(extEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("attribute")) {
				XmlSchemaAttribute attr = handleAttribute(schema, el, schemaEl);
				ext.attributes.add(attr);
			} else if (el.getLocalName().equals("attributeGroup")) {
				XmlSchemaAttributeGroupRef attrGroup = handleAttributeGroupRef(el);
				ext.attributes.add(attrGroup);
			} else if (el.getLocalName().equals("anyAttribute")) {
				ext.anyAttribute = handleAnyAttribute(schema, el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation ann = handleAnnotation(el);
				ext.setAnnotation(ann);
			}
		}
		return ext;
	}

	private XmlSchemaComplexContentRestriction handleComplexContentRestriction(
			XmlSchema schema, Element restrictionEl, Element schemaEl) {

		XmlSchemaComplexContentRestriction restriction = new XmlSchemaComplexContentRestriction();

		if (restrictionEl.hasAttribute("base")) {
			String name = restrictionEl.getAttribute("base");
			restriction.baseTypeName = getRefQName(name, restrictionEl);
		}
		for (Element el = XDOMUtil.getFirstChildElementNS(restrictionEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("sequence")) {
				restriction.particle = handleSequence(schema, el, schemaEl);
			} else if (el.getLocalName().equals("choice")) {
				restriction.particle = handleChoice(schema, el, schemaEl);
			} else if (el.getLocalName().equals("all")) {
				restriction.particle = handleAll(schema, el, schemaEl);
			} else if (el.getLocalName().equals("attribute")) {
				restriction.attributes
						.add(handleAttribute(schema, el, schemaEl));
			} else if (el.getLocalName().equals("attributeGroup")) {
				restriction.attributes.add(handleAttributeGroupRef(el));
			} else if (el.getLocalName().equals("group")) {
				restriction.particle = handleGroupRef(schema, el, schemaEl);
			} else if (el.getLocalName().equals("anyAttribute")) {
				restriction.anyAttribute = handleAnyAttribute(schema, el,
						schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				restriction.setAnnotation(handleAnnotation(el));
			}
		}
		return restriction;
	}

	private XmlSchemaComplexContentExtension handleComplexContentExtension(
			XmlSchema schema, Element extEl, Element schemaEl) {

		XmlSchemaComplexContentExtension ext = new XmlSchemaComplexContentExtension();

		if (extEl.hasAttribute("base")) {
			String name = extEl.getAttribute("base");
			ext.baseTypeName = getRefQName(name, extEl);
		}

		for (Element el = XDOMUtil.getFirstChildElementNS(extEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("sequence")) {
				ext.particle = handleSequence(schema, el, schemaEl);
			} else if (el.getLocalName().equals("choice")) {
				ext.particle = handleChoice(schema, el, schemaEl);
			} else if (el.getLocalName().equals("all")) {
				ext.particle = handleAll(schema, el, schemaEl);
			} else if (el.getLocalName().equals("attribute")) {
				ext.attributes.add(handleAttribute(schema, el, schemaEl));
			} else if (el.getLocalName().equals("attributeGroup")) {
				ext.attributes.add(handleAttributeGroupRef(el));
			} else if (el.getLocalName().equals("group")) {
				ext.particle = handleGroupRef(schema, el, schemaEl);
			} else if (el.getLocalName().equals("anyAttribute")) {
				ext.anyAttribute = handleAnyAttribute(schema, el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				ext.setAnnotation(handleAnnotation(el));
			}
		}
		return ext;
	}

	private XmlSchemaAttributeGroupRef handleAttributeGroupRef(
			Element attrGroupEl) {

		XmlSchemaAttributeGroupRef attrGroup = new XmlSchemaAttributeGroupRef();

		if (attrGroupEl.hasAttribute("ref")) {
			String ref = attrGroupEl.getAttribute("ref");
			attrGroup.refName = getRefQName(ref, attrGroupEl);
		}

		if (attrGroupEl.hasAttribute("id"))
			attrGroup.id = attrGroupEl.getAttribute("id");

		Element annotationEl = XDOMUtil.getFirstChildElementNS(attrGroupEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);
			attrGroup.setAnnotation(annotation);
		}
		return attrGroup;
	}

	private XmlSchemaSequence handleSequence(XmlSchema schema,
			Element sequenceEl, Element schemaEl) {

		XmlSchemaSequence sequence = new XmlSchemaSequence();

		//handle min and max occurences
		sequence.minOccurs = getMinOccurs(sequenceEl);
		sequence.maxOccurs = getMaxOccurs(sequenceEl);

		for (Element el = XDOMUtil.getFirstChildElementNS(sequenceEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("sequence")) {
				XmlSchemaSequence seq = handleSequence(schema, el, schemaEl);
				sequence.items.add(seq);
			} else if (el.getLocalName().equals("element")) {
				XmlSchemaElement element = handleElement(schema, el, schemaEl,
						false);
				sequence.items.add(element);
			} else if (el.getLocalName().equals("group")) {
				XmlSchemaGroupRef group = handleGroupRef(schema, el, schemaEl);
				sequence.items.add(group);
			} else if (el.getLocalName().equals("choice")) {
				XmlSchemaChoice choice = handleChoice(schema, el, schemaEl);
				sequence.items.add(choice);
			} else if (el.getLocalName().equals("any")) {
				XmlSchemaAny any = handleAny(schema, el, schemaEl);
				sequence.items.add(any);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation annotation = handleAnnotation(el);
				sequence.setAnnotation(annotation);
			}
		}
		return sequence;
	}

	/** @noinspection UnusedParameters*/
	private XmlSchemaAny handleAny(XmlSchema schema, Element anyEl,
			Element schemaEl) {

		XmlSchemaAny any = new XmlSchemaAny();

		if (anyEl.hasAttribute("namespace"))
			any.namespace = anyEl.getAttribute("namespace");

		if (anyEl.hasAttribute("processContents")) {
			String processContent = getEnumString(anyEl, "processContents");

			any.processContent = new XmlSchemaContentProcessing(processContent);
		}

		Element annotationEl = XDOMUtil.getFirstChildElementNS(anyEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);
			any.setAnnotation(annotation);
		}
		any.minOccurs = getMinOccurs(anyEl);
		any.maxOccurs = getMaxOccurs(anyEl);

		return any;
	}

	private XmlSchemaChoice handleChoice(XmlSchema schema, Element choiceEl,
			Element schemaEl) {
		XmlSchemaChoice choice = new XmlSchemaChoice();

		if (choiceEl.hasAttribute("id"))
			choice.id = choiceEl.getAttribute("id");

		choice.minOccurs = getMinOccurs(choiceEl);
		choice.maxOccurs = getMaxOccurs(choiceEl);

		for (Element el = XDOMUtil.getFirstChildElementNS(choiceEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("sequence")) {
				XmlSchemaSequence seq = handleSequence(schema, el, schemaEl);
				choice.items.add(seq);
			} else if (el.getLocalName().equals("element")) {
				XmlSchemaElement element = handleElement(schema, el, schemaEl,
						false);
				choice.items.add(element);
			} else if (el.getLocalName().equals("group")) {
				XmlSchemaGroupRef group = handleGroupRef(schema, el, schemaEl);
				choice.items.add(group);
			} else if (el.getLocalName().equals("choice")) {
				XmlSchemaChoice choiceItem = handleChoice(schema, el, schemaEl);
				choice.items.add(choiceItem);
			} else if (el.getLocalName().equals("any")) {
				XmlSchemaAny any = handleAny(schema, el, schemaEl);
				choice.items.add(any);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation annotation = handleAnnotation(el);
				choice.setAnnotation(annotation);
			}
		}
		return choice;
	}

	private XmlSchemaAll handleAll(XmlSchema schema, Element allEl,
			Element schemaEl) {

		XmlSchemaAll all = new XmlSchemaAll();

		//handle min and max occurences
		all.minOccurs = getMinOccurs(allEl);
		all.maxOccurs = getMaxOccurs(allEl);

		for (Element el = XDOMUtil.getFirstChildElementNS(allEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("element")) {
				XmlSchemaElement element = handleElement(schema, el, schemaEl,
						false);
				all.items.add(element);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation annotation = handleAnnotation(el);
				all.setAnnotation(annotation);
			}
		}
		return all;
	}

	private XmlSchemaGroup handleGroup(XmlSchema schema, Element groupEl,
			Element schemaEl) {

		XmlSchemaGroup group = new XmlSchemaGroup();
		group.name = new QName(schema.getTargetNamespace(), groupEl
				.getAttribute("name"));

		for (Element el = XDOMUtil.getFirstChildElementNS(groupEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("all")) {
				group.particle = handleAll(schema, el, schemaEl);
			} else if (el.getLocalName().equals("sequence")) {
				group.particle = handleSequence(schema, el, schemaEl);
			} else if (el.getLocalName().equals("choice")) {
				group.particle = handleChoice(schema, el, schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation groupAnnotation = handleAnnotation(el);
				group.setAnnotation(groupAnnotation);
			}
		}
		return group;
	}

	private XmlSchemaAttributeGroup handleAttributeGroup(XmlSchema schema,
			Element groupEl, Element schemaEl) {
		XmlSchemaAttributeGroup attrGroup = new XmlSchemaAttributeGroup();

		if (groupEl.hasAttribute("name"))
			attrGroup.name = new QName(schema.getTargetNamespace(), groupEl
					.getAttribute("name"));
		if (groupEl.hasAttribute("id"))
			attrGroup.id = groupEl.getAttribute("id");

		for (Element el = XDOMUtil.getFirstChildElementNS(groupEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

			if (el.getLocalName().equals("attribute")) {
				XmlSchemaAttribute attr = handleAttribute(schema, el, schemaEl);
				attrGroup.attributes.add(attr);
			} else if (el.getLocalName().equals("attributeGroup")) {
				XmlSchemaAttributeGroupRef attrGroupRef = handleAttributeGroupRef(el);
				attrGroup.attributes.add(attrGroupRef);
			} else if (el.getLocalName().equals("anyAttribute")) {
				attrGroup.anyAttribute = handleAnyAttribute(schema, el,
						schemaEl);
			} else if (el.getLocalName().equals("annotation")) {
				XmlSchemaAnnotation ann = handleAnnotation(el);
				attrGroup.setAnnotation(ann);
			}
		}
		return attrGroup;
	}

	/** @noinspection UnusedParameters*/
	private XmlSchemaAnyAttribute handleAnyAttribute(XmlSchema schema,
			Element anyAttrEl, Element schemaEl) {

		XmlSchemaAnyAttribute anyAttr = new XmlSchemaAnyAttribute();

		if (anyAttrEl.hasAttribute("namespace"))
			anyAttr.namespace = anyAttrEl.getAttribute("namespace");

		if (anyAttrEl.hasAttribute("processContents")) {

			String contentProcessing = getEnumString(anyAttrEl,
					"processContents");

			anyAttr.processContent = new XmlSchemaContentProcessing(
					contentProcessing);
		}
		if (anyAttrEl.hasAttribute("id"))
			anyAttr.id = anyAttrEl.getAttribute("id");

		Element annotationEl = XDOMUtil.getFirstChildElementNS(anyAttrEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

			anyAttr.setAnnotation(annotation);
		}
		return anyAttr;
	}

	private XmlSchemaGroupRef handleGroupRef(XmlSchema schema, Element groupEl,
			Element schemaEl) {

		XmlSchemaGroupRef group = new XmlSchemaGroupRef();

		group.maxOccurs = getMaxOccurs(groupEl);
		group.minOccurs = getMinOccurs(groupEl);

		Element annotationEl = XDOMUtil.getFirstChildElementNS(groupEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

			group.setAnnotation(annotation);
		}

		if (groupEl.hasAttribute("ref")) {
			String ref = groupEl.getAttribute("ref");
			group.refName = getRefQName(ref, groupEl);
			return group;
		}
		for (Element el = XDOMUtil.getFirstChildElementNS(groupEl,
				XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
				.getNextSiblingElement(el)) {

			if (el.getLocalName().equals("sequence")) {
				group.particle = handleSequence(schema, el, schemaEl);
			} else if (el.getLocalName().equals("all")) {
				group.particle = handleAll(schema, el, schemaEl);
			} else if (el.getLocalName().equals("choice")) {
				group.particle = handleChoice(schema, el, schemaEl);
			}
		}
		return group;
	}

	private QName newLocalQName(String pLocalName) {
		String uri = schema.logicalTargetNamespace;
		if (uri == null) {
			uri = Constants.NULL_NS_URI;
		}
		return new QName(uri, pLocalName);
	}

	/**
	 * Process non-toplevel attributes
	 * @param schema
	 * @param attrEl
	 * @param schemaEl
	 * @return
	 */
	private XmlSchemaAttribute handleAttribute(XmlSchema schema,
			Element attrEl, Element schemaEl) {
		return handleAttribute(schema, attrEl, schemaEl, false);
	}

	/**
	 * Process attributes
	 * @param schema
	 * @param attrEl
	 * @param schemaEl
	 * @param topLevel
	 * @return
	 */
	private XmlSchemaAttribute handleAttribute(XmlSchema schema,
			Element attrEl, Element schemaEl, boolean topLevel) {
		//todo: need to implement different rule of attribute such as
		//restriction between ref and name.  This can be implemented
		//in the compile function
		XmlSchemaAttribute attr = new XmlSchemaAttribute();

		if (attrEl.hasAttribute("name")) {
			String name = attrEl.getAttribute("name");
			//String namespace = (schema.targetNamespace==null)?
			//                  "" :schema.targetNamespace;

			attr.name = name;
		}

		boolean isQualified = schema.getAttributeFormDefault().getValue()
				.equals(XmlSchemaForm.QUALIFIED);
		if (attr.name != null) {
			final String name = attr.name;
			if (topLevel) {
				attr.qualifiedName = newLocalQName(name);
			} else {
				attr.qualifiedName = (isQualified) ? newLocalQName(name)
						: new QName(name);
			}
		}

		if (attrEl.hasAttribute("type")) {
			String name = attrEl.getAttribute("type");
			attr.schemaTypeName = getRefQName(name, attrEl);
		}

		if (attrEl.hasAttribute("default"))
			attr.defaultValue = attrEl.getAttribute("default");

		if (attrEl.hasAttribute("fixed"))
			attr.fixedValue = attrEl.getAttribute("fixed");

		if (attrEl.hasAttribute("form")) {
			String formValue = getEnumString(attrEl, "form");
			attr.form = new XmlSchemaForm(formValue);
		}
		if (attrEl.hasAttribute("id"))
			attr.id = attrEl.getAttribute("id");

		if (attrEl.hasAttribute("use")) {
			String useType = getEnumString(attrEl, "use");
			attr.use = new XmlSchemaUse(useType);
		}
		if (attrEl.hasAttribute("ref")) {
			String name = attrEl.getAttribute("ref");
			attr.refName = getRefQName(name, attrEl);
			attr.name = name;
		}

		Element simpleTypeEl = XDOMUtil.getFirstChildElementNS(attrEl,
				XmlSchema.SCHEMA_NS, "simpleType");

		if (simpleTypeEl != null) {
			attr.schemaType = handleSimpleType(schema, simpleTypeEl, schemaEl);
		}

		Element annotationEl = XDOMUtil.getFirstChildElementNS(attrEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

			attr.setAnnotation(annotation);
		}

		NamedNodeMap attrNodes = attrEl.getAttributes();
		Vector attrs = new Vector();
		NodeNamespaceContext ctx = null;
		for (int i = 0; i < attrNodes.getLength(); i++) {
			Attr att = (Attr) attrNodes.item(i);
			String attName = att.getName();
			if (!attName.equals("name") && !attName.equals("type")
					&& !attName.equals("default") && !attName.equals("fixed")
					&& !attName.equals("form") && !attName.equals("id")
					&& !attName.equals("use") && !attName.equals("ref")) {

				attrs.add(att);
				String value = att.getValue();

				if (value.indexOf(":") > -1) {
					// there is a possiblily of some namespace mapping
					String prefix = value.substring(0, value.indexOf(":"));
					if (ctx == null) {
						ctx = NodeNamespaceContext.getNamespaceContext(attrEl);
					}
					String namespace = ctx.getNamespaceURI(prefix);
					if (!Constants.NULL_NS_URI.equals(namespace)) {
						Attr nsAttr = attrEl.getOwnerDocument()
								.createAttribute("xmlns:" + prefix);
						nsAttr.setValue(namespace);
						attrs.add(nsAttr);
					}
				}
			}
		}

		if (attrs.size() > 0)
			attr.setUnhandledAttributes((Attr[]) attrs.toArray(new Attr[0]));

		//process extra attributes and elements
		processExtensibilityComponents(attr, attrEl);
		return attr;
	}

	/*
	 * handle_simple_content_restriction
	 *
	 * if( restriction has base attribute )
	 *		set the baseType
	 * else if( restriciton has an inline simpleType )
	 *		handleSimpleType
	 * add facets if any to the restriction
	 */

	/*
	 * handle_simple_content_extension
	 *
	 * extension should have a base name and cannot have any inline defn
	 * for( each childNode  )
	 *		if( attribute)
	 *			handleAttribute
	 *		else if( attributeGroup)
	 *			handleAttributeGroup
	 *		else if( anyAttribute)
	 *			handleAnyAttribute
	 */

	/*
	 * ********
	 * handle_complex_content_restriction
	 */
	/**
	 * handle elements
	 * @param schema
	 * @param el
	 * @param schemaEl
	 * @param isGlobal
	 */
	XmlSchemaElement handleElement(XmlSchema schema, Element el,
			Element schemaEl, boolean isGlobal) {

		XmlSchemaElement element = new XmlSchemaElement();

		if (el.getAttributeNode("name") != null)
			element.name = el.getAttribute("name");

		//                String namespace = (schema.targetNamespace==null)?
		//                                      "" : schema.targetNamespace;

		boolean isQualified = schema.getElementFormDefault().getValue().equals(
				XmlSchemaForm.QUALIFIED);
		if (el.hasAttribute("form")) {
			String formDef = el.getAttribute("form");
			element.form = new XmlSchemaForm(formDef);
			isQualified = formDef.equals(XmlSchemaForm.QUALIFIED);
		}

		if (element.name != null) {
			final String name = element.name;
			element.qualifiedName = (isQualified || isGlobal) ? newLocalQName(name)
					: new QName(Constants.NULL_NS_URI, name);
		}

		Element annotationEl = XDOMUtil.getFirstChildElementNS(el,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

			element.setAnnotation(annotation);
		}
		if (el.getAttributeNode("type") != null) {
			String typeName = el.getAttribute("type");
			QName typeQName = element.schemaTypeName = getRefQName(typeName, el);

			XmlSchemaType type = collection.getTypeByQName(typeQName);
			if (type == null) {
				// Could be a forward reference...
				collection.addUnresolvedType(typeQName, element);
			}
			element.schemaType = type;
		} else if (el.getAttributeNode("ref") != null) {
			String refName = el.getAttribute("ref");
			QName refQName = getRefQName(refName, el);
			element.setRefName(refQName);
			element.name = refQName.getLocalPart();
		}

		Element simpleTypeEl, complexTypeEl, keyEl, keyrefEl, uniqueEl;

		if ((simpleTypeEl = XDOMUtil.getFirstChildElementNS(el,
				XmlSchema.SCHEMA_NS, "simpleType")) != null) {

			XmlSchemaSimpleType simpleType = handleSimpleType(schema,
					simpleTypeEl, schemaEl);
			element.schemaType = simpleType;
			element.schemaTypeName = simpleType.getQName();
		} else if ((complexTypeEl = XDOMUtil.getFirstChildElementNS(el,
				XmlSchema.SCHEMA_NS, "complexType")) != null) {

			element.schemaType = handleComplexType(schema, complexTypeEl,
					schemaEl);
		}

		if ((keyEl = XDOMUtil.getFirstChildElementNS(el, XmlSchema.SCHEMA_NS,
				"key")) != null) {
			while (keyEl != null) {
				element.constraints.add(handleConstraint(keyEl, "Key"));
				keyEl = XDOMUtil.getNextSiblingElement(keyEl, "key");
			}
		}

		if ((keyrefEl = XDOMUtil.getFirstChildElementNS(el,
				XmlSchema.SCHEMA_NS, "keyref")) != null) {
			while (keyrefEl != null) {
				XmlSchemaKeyref keyRef = (XmlSchemaKeyref) handleConstraint(
						keyrefEl, "Keyref");
				if (keyrefEl.hasAttribute("refer")) {
					String name = keyrefEl.getAttribute("refer");
					keyRef.refer = getRefQName(name, el);
				}
				element.constraints.add(keyRef);
				keyrefEl = XDOMUtil.getNextSiblingElement(keyrefEl, "keyref");
			}
		}

		if ((uniqueEl = XDOMUtil.getFirstChildElementNS(el,
				XmlSchema.SCHEMA_NS, "unique")) != null) {
			while (uniqueEl != null) {
				element.constraints.add(handleConstraint(uniqueEl, "Unique"));
				uniqueEl = XDOMUtil.getNextSiblingElement(uniqueEl, "unique");
			}
		}

		if (el.hasAttribute("abstract")) {
			element.isAbstract = Boolean.valueOf(el.getAttribute("abstract"))
					.booleanValue();
		}

		if (el.hasAttribute("block"))
			element.block = getDerivation(el, "block");

		if (el.hasAttribute("default"))
			element.defaultValue = el.getAttribute("default");

		if (el.hasAttribute("final"))
			element.finalDerivation = getDerivation(el, "final");

		if (el.hasAttribute("fixed"))
			element.fixedValue = el.getAttribute("fixed");

		if (el.hasAttribute("id"))
			element.id = el.getAttribute("id");

		if (el.hasAttribute("nillable"))
			element.isNillable = Boolean.valueOf(el.getAttribute("nillable"))
					.booleanValue();

		if (el.hasAttribute("substitutionGroup")) {
			String substitutionGroup = el.getAttribute("substitutionGroup");
			element.setSubstitutionGroup(getRefQName(substitutionGroup, el));
		}

		element.minOccurs = getMinOccurs(el);
		element.maxOccurs = getMaxOccurs(el);

		//process extra attributes and elements
		processExtensibilityComponents(element, el);

		return element;
	}

	private XmlSchemaIdentityConstraint handleConstraint(Element constraintEl,
			String type) {

		try {
			XmlSchemaIdentityConstraint constraint = (XmlSchemaIdentityConstraint) Class
					.forName("org.apache.ws.commons.schema.XmlSchema" + type)
					.newInstance();

			if (constraintEl.hasAttribute("name"))
				constraint.name = constraintEl.getAttribute("name");

			if (constraintEl.hasAttribute("refer")) {
				String name = constraintEl.getAttribute("refer");
				((XmlSchemaKeyref) constraint).refer = getRefQName(name,
						constraintEl);
			}
			for (Element el = XDOMUtil.getFirstChildElementNS(constraintEl,
					XmlSchema.SCHEMA_NS); el != null; el = XDOMUtil
					.getNextSiblingElementNS(el, XmlSchema.SCHEMA_NS)) {

				//    String elPrefix = el.getPrefix() == null ? ""
				//     : el.getPrefix();
				//if(elPrefix.equals(schema.schema_ns_prefix)) {
				if (el.getLocalName().equals("selector")) {
					XmlSchemaXPath selectorXPath = new XmlSchemaXPath();
					selectorXPath.xpath = el.getAttribute("xpath");

					Element annotationEl = XDOMUtil.getFirstChildElementNS(el,
							XmlSchema.SCHEMA_NS, "annotation");
					if (annotationEl != null) {
						XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

						selectorXPath.setAnnotation(annotation);
					}
					constraint.selector = selectorXPath;
				} else if (el.getLocalName().equals("field")) {
					XmlSchemaXPath fieldXPath = new XmlSchemaXPath();
					fieldXPath.xpath = el.getAttribute("xpath");
					constraint.fields.add(fieldXPath);

					Element annotationEl = XDOMUtil.getFirstChildElementNS(el,
							XmlSchema.SCHEMA_NS, "annotation");

					if (annotationEl != null) {
						XmlSchemaAnnotation annotation = handleAnnotation(annotationEl);

						fieldXPath.setAnnotation(annotation);
					}
				} else if (el.getLocalName().equals("annotation")) {
					XmlSchemaAnnotation constraintAnnotation = handleAnnotation(el);
					constraint.setAnnotation(constraintAnnotation);
				}
			}
			return constraint;
		} catch (ClassNotFoundException e) {
			throw new XmlSchemaException(e.getMessage());
		} catch (InstantiationException e) {
			throw new XmlSchemaException(e.getMessage());
		} catch (IllegalAccessException e) {
			throw new XmlSchemaException(e.getMessage());
		}
	}

	/**
	 * Hanlde the import
	 * @param schema
	 * @param importEl
	 * @param schemaEl
	 * @return XmlSchemaObject
	 */
	XmlSchemaImport handleImport(XmlSchema schema, Element importEl,
			Element schemaEl) {

		XmlSchemaImport schemaImport = new XmlSchemaImport();

		Element annotationEl = XDOMUtil.getFirstChildElementNS(importEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation importAnnotation = handleAnnotation(annotationEl);
			schemaImport.setAnnotation(importAnnotation);
		}

		final String uri = schemaImport.namespace = importEl
				.getAttribute("namespace");
		schemaImport.schemaLocation = importEl.getAttribute("schemaLocation");

		TargetNamespaceValidator validator = new TargetNamespaceValidator() {
			private boolean isEmpty(String pValue) {
				return pValue == null || Constants.NULL_NS_URI.equals(pValue);
			}

			public void validate(XmlSchema pSchema) {
				final boolean valid;
				if (isEmpty(uri)) {
					valid = isEmpty(pSchema.syntacticalTargetNamespace);
				} else {
					valid = pSchema.syntacticalTargetNamespace.equals(uri);
				}
				if (!valid) {
					throw new XmlSchemaException(
							"An imported schema was announced to have the namespace "
									+ uri + ", but has the namespace "
									+ pSchema.syntacticalTargetNamespace);
				}
			}
		};
		if ((schemaImport.schemaLocation != null)
				&& (!schemaImport.schemaLocation.equals(""))) {
			if (schema.getSourceURI() != null) {
				schemaImport.schema = resolveXmlSchema(uri,
						schemaImport.schemaLocation, schema.getSourceURI(),
						validator);
			} else {
				schemaImport.schema = resolveXmlSchema(schemaImport.namespace,
						schemaImport.schemaLocation, validator);
			}
		}
		return schemaImport;
	}

	/**
	 * Handles the include
	 * @param schema
	 * @param includeEl
	 * @param schemaEl
	 */
	XmlSchemaInclude handleInclude(final XmlSchema schema, Element includeEl,
			Element schemaEl) {

		XmlSchemaInclude include = new XmlSchemaInclude();

		Element annotationEl = XDOMUtil.getFirstChildElementNS(includeEl,
				XmlSchema.SCHEMA_NS, "annotation");

		if (annotationEl != null) {
			XmlSchemaAnnotation includeAnnotation = handleAnnotation(annotationEl);
			include.setAnnotation(includeAnnotation);
		}

		include.schemaLocation = includeEl.getAttribute("schemaLocation");

		//includes are not supposed to have a target namespace
		// we should be passing in a null in place of the target
		//namespace

		final TargetNamespaceValidator validator = newIncludeValidator(schema);
		if (schema.getSourceURI() != null) {
			include.schema = resolveXmlSchema(schema.logicalTargetNamespace,
					include.schemaLocation, schema.getSourceURI(), validator);
		} else {
			include.schema = resolveXmlSchema(schema.logicalTargetNamespace,
					include.schemaLocation, validator);
		}

		//process extra attributes and elements
		processExtensibilityComponents(include, includeEl);
		return include;
	}

	private TargetNamespaceValidator newIncludeValidator(final XmlSchema schema) {
		return new TargetNamespaceValidator() {
			private boolean isEmpty(String pValue) {
				return pValue == null || Constants.NULL_NS_URI.equals(pValue);
			}

			public void validate(XmlSchema pSchema) {
				if (isEmpty(pSchema.syntacticalTargetNamespace)) {
					pSchema.logicalTargetNamespace = schema.logicalTargetNamespace;
				} else {
					if (!pSchema.syntacticalTargetNamespace
							.equals(schema.logicalTargetNamespace)) {
						String msg = "An included schema was announced to have the default target namespace";
						if (!isEmpty(schema.logicalTargetNamespace)) {
							msg += " or the target namespace "
									+ schema.logicalTargetNamespace;
						}
						throw new XmlSchemaException(msg
								+ ", but has the target namespace "
								+ pSchema.logicalTargetNamespace);
					}
				}
			}
		};
	}

	/**
	 * Handles the annotation
	 * Traversing if encounter appinfo or documentation
	 * add it to annotation collection
	 *
	 */
	XmlSchemaAnnotation handleAnnotation(Element annotEl) {
		XmlSchemaObjectCollection content = new XmlSchemaObjectCollection();
		XmlSchemaAppInfo appInfoObj;
		XmlSchemaDocumentation docsObj;

		for (Element appinfo = XDOMUtil.getFirstChildElementNS(annotEl,
				XmlSchema.SCHEMA_NS, "appinfo"); appinfo != null; appinfo = XDOMUtil
				.getNextSiblingElementNS(appinfo, XmlSchema.SCHEMA_NS,
						"appinfo")) {

			appInfoObj = handleAppInfo(appinfo);
			if (appInfoObj != null) {
				content.add(appInfoObj);
			}
		}
		for (Element documentation = XDOMUtil.getFirstChildElementNS(annotEl,
				XmlSchema.SCHEMA_NS, "documentation"); documentation != null; documentation = XDOMUtil
				.getNextSiblingElementNS(documentation,

				XmlSchema.SCHEMA_NS, "documentation")) {

			docsObj = handleDocumentation(documentation);
			if (docsObj != null) {
				content.add(docsObj);
			}
		}

		XmlSchemaAnnotation annotation = new XmlSchemaAnnotation();
		annotation.items = content;

		//process extra attributes and elements
		processExtensibilityComponents(annotation, annotEl);
		return annotation;
	}

	/**
	 * create new XmlSchemaAppinfo and add value goten from element
	 * to this obj
	 * @param content
	 */
	XmlSchemaAppInfo handleAppInfo(Element content) {
		XmlSchemaAppInfo appInfo = new XmlSchemaAppInfo();
		NodeList markup = getChildren(content);

		if (!content.hasAttribute("source")
				&& (markup == null || markup.getLength() <= 0)) {
			return null;
		}
		appInfo.setSource(getAttribute(content, "source"));
		appInfo.setMarkup(markup);
		return appInfo;
	}

	//iterate each documentation element, create new XmlSchemaAppinfo and add to collection
	XmlSchemaDocumentation handleDocumentation(Element content) {
		XmlSchemaDocumentation documentation = new XmlSchemaDocumentation();
		NodeList markup = getChildren(content);

		if (!content.hasAttribute("source")
				&& !content.hasAttribute("xml:lang")
				&& (markup == null || markup.getLength() <= 0))
			return null;

		documentation.setSource(getAttribute(content, "source"));
		documentation.setLanguage(getAttribute(content, "xml:lang"));
		documentation.setMarkup(getChildren(content));

		return documentation;
	}

	private String getAttribute(Element content, String attrName) {
		if (content.hasAttribute(attrName))
			return content.getAttribute(attrName);
		return null;
	}

	private NodeList getChildren(Element content) {
		NodeList childs = content.getChildNodes();
		if (childs.getLength() > 0)
			return childs;
		return null;
	}

	long getMinOccurs(Element el) {
		try {
			if (el.getAttributeNode("minOccurs") != null) {
				String value = el.getAttribute("minOccurs");
				if (value.equals("unbounded"))
					return Long.MAX_VALUE;
				else
					return Long.parseLong(value);
			}
			return 1;
		} catch (java.lang.NumberFormatException e) {
			return 1;
		}
	}

	long getMaxOccurs(Element el) {
		try {
			if (el.getAttributeNode("maxOccurs") != null) {
				String value = el.getAttribute("maxOccurs");
				if (value.equals("unbounded"))
					return Long.MAX_VALUE;
				else
					return Long.parseLong(value);
			}
			return 1;
		} catch (java.lang.NumberFormatException e) {
			return 1;
		}
	}

	XmlSchemaForm getFormDefault(Element el, String attrName) {
		if (el.getAttributeNode(attrName) != null) {
			String value = el.getAttribute(attrName);
			return new XmlSchemaForm(value);
		} else
			return new XmlSchemaForm("unqualified");
	}

	//Check value entered by user and change according to .net spec,
	//according to w3c spec have to be "#all"
	//but in .net the valid enum value is "all".
	XmlSchemaDerivationMethod getDerivation(Element el, String attrName) {
		if (el.hasAttribute(attrName) && !el.getAttribute(attrName).equals("")) {
			//#all | List of (extension | restriction | substitution
			String derivationMethod = el.getAttribute(attrName).trim();
			if (derivationMethod.equals("#all"))
				return new XmlSchemaDerivationMethod(
						Constants.BlockConstants.ALL);
			else
				return new XmlSchemaDerivationMethod(derivationMethod);
		}
		return new XmlSchemaDerivationMethod(Constants.BlockConstants.NONE);
	}

	//Check value entered by user and change according to .net spec, user
	String getEnumString(Element el, String attrName) {
		if (el.hasAttribute(attrName)) {
			return el.getAttribute(attrName).trim();
		}
		return Constants.BlockConstants.NONE;
	}

	/**
	 * Resolve the schemas
	 * @param targetNamespace
	 * @param schemaLocation
	 */
	XmlSchema resolveXmlSchema(String targetNamespace, String schemaLocation,
			String baseUri, TargetNamespaceValidator validator) {

        String schemaKey = null;
        if (resolvedSchemas != null) {  // cache is initialized, use it
            // Not being very smart about this at the moment.  One could, for example,
            // see that the schemaLocation or baseUri is the same as another, but differs
            // only by a trailing slash.  As it is now, we assume a single character difference
            // means it's a schema that has yet to be resolved.
            schemaKey = Thread.currentThread().getId() + targetNamespace + schemaLocation + baseUri;
            SoftReference softref = (SoftReference)resolvedSchemas.get(schemaKey);
            if (softref != null) {
                XmlSchema resolvedSchema = (XmlSchema)softref.get();
                if (resolvedSchema != null) {
                    return resolvedSchema;
                }
            }
        }
        
		//use the entity resolver provided if the schema location is present null
		if (schemaLocation != null && !"".equals(schemaLocation)) {
			InputSource source = collection.getSchemaResolver().resolveEntity(
					targetNamespace, schemaLocation, baseUri);

			//the entity resolver was unable to resolve this!!
			if (source == null) {
				//try resolving it with the target namespace only with the 
				//known namespace map
				XmlSchema schema = collection.getKnownSchema(targetNamespace);
				if (schema != null) {
					return schema;
				}else{
					return null;
				}
			}
			final String systemId = source.getSystemId() == null ? schemaLocation
					: source.getSystemId();
			// Push repaired system id back into source where read sees it.
			// It is perhaps a bad thing to patch the source, but this fixes
			// a problem.
			source.setSystemId(systemId);
			final SchemaKey key = new XmlSchemaCollection.SchemaKey(
					targetNamespace, systemId);
			XmlSchema schema = collection.getSchema(key);
			if (schema != null) {
				return schema;
			}
			if (collection.check(key)) {
				collection.push(key);
				try {
                    XmlSchema readSchema = collection.read(source, null, validator);
                    if (resolvedSchemas != null) {
                        resolvedSchemas.put(schemaKey, new SoftReference(readSchema));
                    }
					return readSchema;
				} catch (Exception e) {
					throw new RuntimeException(e);
				} finally {
					collection.pop();
				}
			}
		}else{
			XmlSchema schema = collection.getKnownSchema(targetNamespace);
			if (schema != null) {
				return schema;
			}
		}

		return null;
	}

	/**
	 * Resolve the schemas
	 * @param targetNamespace
	 * @param schemaLocation
	 */
	XmlSchema resolveXmlSchema(String targetNamespace, String schemaLocation,
			TargetNamespaceValidator validator) {

		return resolveXmlSchema(targetNamespace, schemaLocation,
				collection.baseUri, validator);

	}

	/**
	 * A generic method to process the extra attributes and the the extra
	 * elements present within the schema.
	 * What are considered extensions are  child elements with non schema namespace
	 * and child attributes with any namespace
	 * @param schemaObject
	 * @param parentElement
	 */
	private void processExtensibilityComponents(XmlSchemaObject schemaObject,
			Element parentElement) {

		if (extReg != null) {
			//process attributes
			NamedNodeMap attributes = parentElement.getAttributes();
			for (int i = 0; i < attributes.getLength(); i++) {
				Attr attribute = (Attr) attributes.item(i);

				String namespaceURI = attribute.getNamespaceURI();
				String name = attribute.getLocalName();

				if (namespaceURI != null
						&& !"".equals(namespaceURI)
						&& //ignore unqualified attributes
						!namespaceURI
								.startsWith(Constants.XMLNS_ATTRIBUTE_NS_URI) && //ignore namespaces
						!Constants.URI_2001_SCHEMA_XSD.equals(namespaceURI))
				//does not belong to the schema namespace by any chance!
				{
					QName qName = new QName(namespaceURI, name);
					extReg.deserializeExtension(schemaObject, qName, attribute);

				}
			}

			//process elements
			Node child = parentElement.getFirstChild();
			while (child != null) {
				if (child.getNodeType() == Node.ELEMENT_NODE) {
					Element extElement = (Element) child;
					String namespaceURI = extElement.getNamespaceURI();
					String name = extElement.getLocalName();

					if (namespaceURI != null
							&& !Constants.URI_2001_SCHEMA_XSD
									.equals(namespaceURI))
					//does not belong to the schema namespace
					{
						QName qName = new QName(namespaceURI, name);
						extReg.deserializeExtension(schemaObject, qName,
								extElement);
					}
				}
				child = child.getNextSibling();
			}
		}

	}

}