src/xmlpatterns/schema/qxsdschemaresolver.cpp
changeset 0 1918ee327afb
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/xmlpatterns/schema/qxsdschemaresolver.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,1736 @@
+/****************************************************************************
+**
+** Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtXmlPatterns module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qxsdschemaresolver_p.h"
+
+#include "qderivedinteger_p.h"
+#include "qderivedstring_p.h"
+#include "qqnamevalue_p.h"
+#include "qxsdattributereference_p.h"
+#include "qxsdparticlechecker_p.h"
+#include "qxsdreference_p.h"
+#include "qxsdschemacontext_p.h"
+#include "qxsdschemahelper_p.h"
+#include "qxsdschemaparsercontext_p.h"
+#include "qxsdschematypesfactory_p.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+XsdSchemaResolver::XsdSchemaResolver(const QExplicitlySharedDataPointer<XsdSchemaContext> &context, const XsdSchemaParserContext *parserContext)
+    : m_context(context)
+    , m_checker(parserContext->checker())
+    , m_namePool(parserContext->namePool())
+    , m_schema(parserContext->schema())
+{
+    m_keyReferences.reserve(20);
+    m_simpleRestrictionBases.reserve(20);
+    m_simpleListTypes.reserve(20);
+    m_simpleUnionTypes.reserve(20);
+    m_elementTypes.reserve(20);
+    m_complexBaseTypes.reserve(20);
+    m_attributeTypes.reserve(20);
+    m_alternativeTypes.reserve(20);
+    m_alternativeTypeElements.reserve(20);
+    m_substitutionGroupAffiliations.reserve(20);
+
+    m_predefinedSchemaTypes = m_context->schemaTypeFactory()->types().values();
+}
+
+XsdSchemaResolver::~XsdSchemaResolver()
+{
+}
+
+void XsdSchemaResolver::resolve()
+{
+    m_checker->addComponentLocationHash(m_componentLocationHash);
+
+    // resolve the base types for all types
+    resolveSimpleRestrictionBaseTypes();
+    resolveComplexBaseTypes();
+
+    // do the basic checks which depend on having a base type available
+    m_checker->basicCheck();
+
+    // resolve further types that only map a type name to a type object
+    resolveSimpleListType();
+    resolveSimpleUnionTypes();
+    resolveElementTypes();
+    resolveAttributeTypes();
+    resolveAlternativeTypes();
+
+    // resolve objects that do not need information about inheritance
+    resolveKeyReferences();
+    resolveSubstitutionGroupAffiliations();
+
+    // resolve objects that do need information about inheritance
+    resolveSimpleRestrictions();
+    resolveSimpleContentComplexTypes();
+
+    // resolve objects which replace place holders
+    resolveTermReferences();
+    resolveAttributeTermReferences();
+
+    // resolve additional objects that do need information about inheritance
+    resolveAttributeInheritance();
+    resolveComplexContentComplexTypes();
+    resolveSubstitutionGroups();
+
+    resolveEnumerationFacetValues();
+
+    checkRedefinedGroups();
+    checkRedefinedAttributeGroups();
+
+    // check the constraining facets before we resolve them
+    m_checker->checkConstrainingFacets();
+
+    // add it again, as we may have added new components in the meantime
+    m_checker->addComponentLocationHash(m_componentLocationHash);
+
+    m_checker->check();
+}
+
+void XsdSchemaResolver::addKeyReference(const XsdElement::Ptr &element, const XsdIdentityConstraint::Ptr &keyRef, const QXmlName &reference, const QSourceLocation &location)
+{
+    KeyReference item;
+    item.element = element;
+    item.keyRef = keyRef;
+    item.reference = reference;
+    item.location = location;
+
+    m_keyReferences.append(item);
+}
+
+void XsdSchemaResolver::addSimpleRestrictionBase(const XsdSimpleType::Ptr &simpleType, const QXmlName &baseName, const QSourceLocation &location)
+{
+    SimpleRestrictionBase item;
+    item.simpleType = simpleType;
+    item.baseName = baseName;
+    item.location = location;
+
+    m_simpleRestrictionBases.append(item);
+}
+
+void XsdSchemaResolver::removeSimpleRestrictionBase(const XsdSimpleType::Ptr &type)
+{
+    for (int i = 0; i < m_simpleRestrictionBases.count(); ++i) {
+        if (m_simpleRestrictionBases.at(i).simpleType == type) {
+            m_simpleRestrictionBases.remove(i);
+            break;
+        }
+    }
+}
+
+void XsdSchemaResolver::addSimpleListType(const XsdSimpleType::Ptr &simpleType, const QXmlName &typeName, const QSourceLocation &location)
+{
+    SimpleListType item;
+    item.simpleType = simpleType;
+    item.typeName = typeName;
+    item.location = location;
+
+    m_simpleListTypes.append(item);
+}
+
+void XsdSchemaResolver::addSimpleUnionTypes(const XsdSimpleType::Ptr &simpleType, const QList<QXmlName> &typeNames, const QSourceLocation &location)
+{
+    SimpleUnionType item;
+    item.simpleType = simpleType;
+    item.typeNames = typeNames;
+    item.location = location;
+
+    m_simpleUnionTypes.append(item);
+}
+
+void XsdSchemaResolver::addElementType(const XsdElement::Ptr &element, const QXmlName &typeName, const QSourceLocation &location)
+{
+    ElementType item;
+    item.element = element;
+    item.typeName = typeName;
+    item.location = location;
+
+    m_elementTypes.append(item);
+}
+
+void XsdSchemaResolver::addComplexBaseType(const XsdComplexType::Ptr &complexType, const QXmlName &baseName, const QSourceLocation &location, const XsdFacet::Hash &facets)
+{
+    ComplexBaseType item;
+    item.complexType = complexType;
+    item.baseName = baseName;
+    item.location = location;
+    item.facets = facets;
+
+    m_complexBaseTypes.append(item);
+}
+
+void XsdSchemaResolver::removeComplexBaseType(const XsdComplexType::Ptr &type)
+{
+    for (int i = 0; i < m_complexBaseTypes.count(); ++i) {
+        if (m_complexBaseTypes.at(i).complexType == type) {
+            m_complexBaseTypes.remove(i);
+            break;
+        }
+    }
+}
+
+void XsdSchemaResolver::addComplexContentType(const XsdComplexType::Ptr &complexType, const XsdParticle::Ptr &content, bool mixed)
+{
+    ComplexContentType item;
+    item.complexType = complexType;
+    item.explicitContent = content;
+    item.effectiveMixed = mixed;
+    m_complexContentTypes.append(item);
+}
+
+void XsdSchemaResolver::addAttributeType(const XsdAttribute::Ptr &attribute, const QXmlName &typeName, const QSourceLocation &location)
+{
+    AttributeType item;
+    item.attribute = attribute;
+    item.typeName = typeName;
+    item.location = location;
+
+    m_attributeTypes.append(item);
+}
+
+void XsdSchemaResolver::addAlternativeType(const XsdAlternative::Ptr &alternative, const QXmlName &typeName, const QSourceLocation &location)
+{
+    AlternativeType item;
+    item.alternative = alternative;
+    item.typeName = typeName;
+    item.location = location;
+
+    m_alternativeTypes.append(item);
+}
+
+void XsdSchemaResolver::addAlternativeType(const XsdAlternative::Ptr &alternative, const XsdElement::Ptr &element)
+{
+    AlternativeTypeElement item;
+    item.alternative = alternative;
+    item.element = element;
+
+    m_alternativeTypeElements.append(item);
+}
+
+void XsdSchemaResolver::addSubstitutionGroupAffiliation(const XsdElement::Ptr &element, const QList<QXmlName> &elementNames, const QSourceLocation &location)
+{
+    SubstitutionGroupAffiliation item;
+    item.element = element;
+    item.elementNames = elementNames;
+    item.location = location;
+
+    m_substitutionGroupAffiliations.append(item);
+}
+
+void XsdSchemaResolver::addSubstitutionGroupType(const XsdElement::Ptr &element)
+{
+    m_substitutionGroupTypes.append(element);
+}
+
+void XsdSchemaResolver::addComponentLocationHash(const ComponentLocationHash &hash)
+{
+    m_componentLocationHash.unite(hash);
+}
+
+void XsdSchemaResolver::addEnumerationFacetValue(const AtomicValue::Ptr &facetValue, const NamespaceSupport &namespaceSupport)
+{
+    m_enumerationFacetValues.insert(facetValue, namespaceSupport);
+}
+
+void XsdSchemaResolver::addRedefinedGroups(const XsdModelGroup::Ptr &redefinedGroup, const XsdModelGroup::Ptr &group)
+{
+    RedefinedGroups item;
+    item.redefinedGroup = redefinedGroup;
+    item.group = group;
+
+    m_redefinedGroups.append(item);
+}
+
+void XsdSchemaResolver::addRedefinedAttributeGroups(const XsdAttributeGroup::Ptr &redefinedGroup, const XsdAttributeGroup::Ptr &group)
+{
+    RedefinedAttributeGroups item;
+    item.redefinedGroup = redefinedGroup;
+    item.group = group;
+
+    m_redefinedAttributeGroups.append(item);
+}
+
+void XsdSchemaResolver::addAllGroupCheck(const XsdReference::Ptr &reference)
+{
+    m_allGroups.insert(reference);
+}
+
+void XsdSchemaResolver::copyDataTo(const XsdSchemaResolver::Ptr &other) const
+{
+    other->m_keyReferences << m_keyReferences;
+    other->m_simpleRestrictionBases << m_simpleRestrictionBases;
+    other->m_simpleListTypes << m_simpleListTypes;
+    other->m_simpleUnionTypes << m_simpleUnionTypes;
+    other->m_elementTypes << m_elementTypes;
+    other->m_complexBaseTypes << m_complexBaseTypes;
+    other->m_complexContentTypes << m_complexContentTypes;
+    other->m_attributeTypes << m_attributeTypes;
+    other->m_alternativeTypes << m_alternativeTypes;
+    other->m_alternativeTypeElements << m_alternativeTypeElements;
+    other->m_substitutionGroupAffiliations << m_substitutionGroupAffiliations;
+    other->m_substitutionGroupTypes << m_substitutionGroupTypes;
+}
+
+QXmlName XsdSchemaResolver::baseTypeNameOfType(const SchemaType::Ptr &type) const
+{
+    for (int i = 0; i < m_simpleRestrictionBases.count(); ++i) {
+        if (m_simpleRestrictionBases.at(i).simpleType == type)
+            return m_simpleRestrictionBases.at(i).baseName;
+    }
+
+    for (int i = 0; i < m_complexBaseTypes.count(); ++i) {
+        if (m_complexBaseTypes.at(i).complexType == type)
+            return m_complexBaseTypes.at(i).baseName;
+    }
+
+    return QXmlName();
+}
+
+QXmlName XsdSchemaResolver::typeNameOfAttribute(const XsdAttribute::Ptr &attribute) const
+{
+    for (int i = 0; i < m_attributeTypes.count(); ++i) {
+        if (m_attributeTypes.at(i).attribute == attribute)
+            return m_attributeTypes.at(i).typeName;
+    }
+
+    return QXmlName();
+}
+
+void XsdSchemaResolver::setDefaultOpenContent(const XsdComplexType::OpenContent::Ptr &openContent, bool appliesToEmpty)
+{
+    m_defaultOpenContent = openContent;
+    m_defaultOpenContentAppliesToEmpty = appliesToEmpty;
+}
+
+void XsdSchemaResolver::resolveKeyReferences()
+{
+    for (int i = 0; i < m_keyReferences.count(); ++i) {
+        const KeyReference ref = m_keyReferences.at(i);
+
+        const XsdIdentityConstraint::Ptr constraint = m_schema->identityConstraint(ref.reference);
+        if (!constraint) {
+            m_context->error(QtXmlPatterns::tr("%1 references unknown %2 or %3 element %4.")
+                                              .arg(formatKeyword(ref.keyRef->displayName(m_namePool)))
+                                              .arg(formatElement("key"))
+                                              .arg(formatElement("unique"))
+                                              .arg(formatKeyword(m_namePool, ref.reference)),
+                             XsdSchemaContext::XSDError, ref.location);
+            return;
+        }
+
+        if (constraint->category() != XsdIdentityConstraint::Key && constraint->category() != XsdIdentityConstraint::Unique) { // only key and unique can be referenced
+            m_context->error(QtXmlPatterns::tr("%1 references identity constraint %2 that is no %3 or %4 element.")
+                                              .arg(formatKeyword(ref.keyRef->displayName(m_namePool)))
+                                              .arg(formatKeyword(m_namePool, ref.reference))
+                                              .arg(formatElement("key"))
+                                              .arg(formatElement("unique")),
+                             XsdSchemaContext::XSDError, ref.location);
+            return;
+        }
+
+        if (constraint->fields().count() != ref.keyRef->fields().count()) {
+            m_context->error(QtXmlPatterns::tr("%1 has a different number of fields from the identity constraint %2 that it references.")
+                                              .arg(formatKeyword(ref.keyRef->displayName(m_namePool)))
+                                              .arg(formatKeyword(m_namePool, ref.reference)),
+                             XsdSchemaContext::XSDError, ref.location);
+            return;
+        }
+
+        ref.keyRef->setReferencedKey(constraint);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleRestrictionBaseTypes()
+{
+    // iterate over all simple types that are derived by restriction
+    for (int i = 0; i < m_simpleRestrictionBases.count(); ++i) {
+        const SimpleRestrictionBase item = m_simpleRestrictionBases.at(i);
+
+        // find the base type
+        SchemaType::Ptr type = m_schema->type(item.baseName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.baseName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Base type %1 of %2 element cannot be resolved.")
+                                                  .arg(formatType(m_namePool, item.baseName))
+                                                  .arg(formatElement("restriction")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        item.simpleType->setWxsSuperType(type);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleRestrictions()
+{
+    XsdSimpleType::List simpleTypes;
+
+    // first collect the global simple types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (types.at(i)->isSimpleType() && (types.at(i)->derivationMethod() == SchemaType::DerivationRestriction))
+            simpleTypes.append(types.at(i));
+    }
+
+    // then collect all anonymous simple types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (anonymousTypes.at(i)->isSimpleType() && (anonymousTypes.at(i)->derivationMethod() == SchemaType::DerivationRestriction))
+            simpleTypes.append(anonymousTypes.at(i));
+    }
+
+    QSet<XsdSimpleType::Ptr> visitedTypes;
+    for (int i = 0; i < simpleTypes.count(); ++i) {
+        resolveSimpleRestrictions(simpleTypes.at(i), visitedTypes);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleRestrictions(const XsdSimpleType::Ptr &simpleType, QSet<XsdSimpleType::Ptr> &visitedTypes)
+{
+    if (visitedTypes.contains(simpleType))
+        return;
+    else
+        visitedTypes.insert(simpleType);
+
+    if (simpleType->derivationMethod() != XsdSimpleType::DerivationRestriction)
+        return;
+
+    // as xs:NMTOKENS, xs:ENTITIES and xs:IDREFS are provided by our XsdSchemaTypesFactory, they are
+    // setup correctly already and shouldn't be handled here
+    if (m_predefinedSchemaTypes.contains(simpleType))
+        return;
+
+    const SchemaType::Ptr baseType = simpleType->wxsSuperType();
+    Q_ASSERT(baseType);
+
+    if (baseType->isDefinedBySchema())
+        resolveSimpleRestrictions(XsdSimpleType::Ptr(baseType), visitedTypes);
+
+    simpleType->setCategory(baseType->category());
+
+    if (simpleType->category() == XsdSimpleType::SimpleTypeAtomic) {
+        QSet<AnySimpleType::Ptr> visitedPrimitiveTypes;
+        const AnySimpleType::Ptr primitiveType = findPrimitiveType(baseType, visitedPrimitiveTypes);
+        simpleType->setPrimitiveType(primitiveType);
+    } else if (simpleType->category() == XsdSimpleType::SimpleTypeList) {
+        const XsdSimpleType::Ptr simpleBaseType = baseType;
+        simpleType->setItemType(simpleBaseType->itemType());
+    } else if (simpleType->category() == XsdSimpleType::SimpleTypeUnion) {
+        const XsdSimpleType::Ptr simpleBaseType = baseType;
+        simpleType->setMemberTypes(simpleBaseType->memberTypes());
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleListType()
+{
+    // iterate over all simple types where the item type shall be resolved
+    for (int i = 0; i < m_simpleListTypes.count(); ++i) {
+        const SimpleListType item = m_simpleListTypes.at(i);
+
+        // try to resolve the name
+        SchemaType::Ptr type = m_schema->type(item.typeName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.typeName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Item type %1 of %2 element cannot be resolved.")
+                                                  .arg(formatType(m_namePool, item.typeName))
+                                                  .arg(formatElement("list")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        item.simpleType->setItemType(type);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleUnionTypes()
+{
+    // iterate over all simple types where the union member types shall be resolved
+    for (int i = 0; i < m_simpleUnionTypes.count(); ++i) {
+        const SimpleUnionType item = m_simpleUnionTypes.at(i);
+
+        AnySimpleType::List memberTypes;
+
+        // iterate over all union member type names
+        const QList<QXmlName> typeNames = item.typeNames;
+        for (int j = 0; j < typeNames.count(); ++j) {
+            const QXmlName typeName = typeNames.at(j);
+
+            // try to resolve the name
+            SchemaType::Ptr type = m_schema->type(typeName);
+            if (!type) {
+                // maybe it's a basic type...
+                type = m_context->schemaTypeFactory()->createSchemaType(typeName);
+                if (!type) {
+                    m_context->error(QtXmlPatterns::tr("Member type %1 of %2 element cannot be resolved.")
+                                                      .arg(formatType(m_namePool, typeName))
+                                                      .arg(formatElement("union")),
+                                     XsdSchemaContext::XSDError, item.location);
+                    return;
+                }
+            }
+
+            memberTypes.append(type);
+        }
+
+        // append the types that have been defined as <simpleType> children
+        memberTypes << item.simpleType->memberTypes();
+
+        item.simpleType->setMemberTypes(memberTypes);
+    }
+}
+
+void XsdSchemaResolver::resolveElementTypes()
+{
+    for (int i = 0; i < m_elementTypes.count(); ++i) {
+        const ElementType item = m_elementTypes.at(i);
+
+        SchemaType::Ptr type = m_schema->type(item.typeName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.typeName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Type %1 of %2 element cannot be resolved.")
+                                                  .arg(formatType(m_namePool, item.typeName))
+                                                  .arg(formatElement("element")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        item.element->setType(type);
+    }
+}
+
+void XsdSchemaResolver::resolveComplexBaseTypes()
+{
+    for (int i = 0; i < m_complexBaseTypes.count(); ++i) {
+        const ComplexBaseType item = m_complexBaseTypes.at(i);
+
+        SchemaType::Ptr type = m_schema->type(item.baseName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.baseName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Base type %1 of complex type cannot be resolved.").arg(formatType(m_namePool, item.baseName)), XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        if (item.complexType->contentType()->variety() == XsdComplexType::ContentType::Simple) {
+            if (type->isComplexType() && type->isDefinedBySchema()) {
+                const XsdComplexType::Ptr baseType = type;
+                if (baseType->contentType()->variety() != XsdComplexType::ContentType::Simple) {
+                    m_context->error(QtXmlPatterns::tr("%1 cannot have complex base type that has a %2.")
+                                                      .arg(formatElement("simpleContent"))
+                                                      .arg(formatElement("complexContent")),
+                                     XsdSchemaContext::XSDError, item.location);
+                    return;
+                }
+            }
+        }
+
+        item.complexType->setWxsSuperType(type);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleContentComplexTypes()
+{
+    XsdComplexType::List complexTypes;
+
+    // first collect the global complex types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (types.at(i)->isComplexType() && types.at(i)->isDefinedBySchema())
+            complexTypes.append(types.at(i));
+    }
+
+    // then collect all anonymous simple types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (anonymousTypes.at(i)->isComplexType() && anonymousTypes.at(i)->isDefinedBySchema())
+            complexTypes.append(anonymousTypes.at(i));
+    }
+
+    QSet<XsdComplexType::Ptr> visitedTypes;
+    for (int i = 0; i < complexTypes.count(); ++i) {
+        if (XsdComplexType::Ptr(complexTypes.at(i))->contentType()->variety() == XsdComplexType::ContentType::Simple)
+            resolveSimpleContentComplexTypes(complexTypes.at(i), visitedTypes);
+    }
+}
+
+void XsdSchemaResolver::resolveSimpleContentComplexTypes(const XsdComplexType::Ptr &complexType, QSet<XsdComplexType::Ptr> &visitedTypes)
+{
+    if (visitedTypes.contains(complexType))
+        return;
+    else
+        visitedTypes.insert(complexType);
+
+    const SchemaType::Ptr baseType = complexType->wxsSuperType();
+
+    // at this point simple types have been resolved already, so we care about
+    // complex types here only
+
+    // http://www.w3.org/TR/xmlschema11-1/#dcl.ctd.ctsc
+    // 1
+    if (baseType->isComplexType() && baseType->isDefinedBySchema()) {
+        const XsdComplexType::Ptr complexBaseType = baseType;
+
+        resolveSimpleContentComplexTypes(complexBaseType, visitedTypes);
+
+        if (complexBaseType->contentType()->variety() == XsdComplexType::ContentType::Simple) {
+            if (complexType->derivationMethod() == XsdComplexType::DerivationRestriction) {
+                if (complexType->contentType()->simpleType()) {
+                    // 1.1 contains the content of the <simpleType> already
+                } else {
+                    // 1.2
+                    const XsdSimpleType::Ptr anonType(new XsdSimpleType());
+                    anonType->setCategory(complexBaseType->contentType()->simpleType()->category());
+                    anonType->setDerivationMethod(XsdSimpleType::DerivationRestriction);
+                    anonType->setWxsSuperType(complexBaseType->contentType()->simpleType());
+                    anonType->setFacets(complexTypeFacets(complexType));
+
+                    QSet<AnySimpleType::Ptr> visitedPrimitiveTypes;
+                    const AnySimpleType::Ptr primitiveType = findPrimitiveType(anonType->wxsSuperType(), visitedPrimitiveTypes);
+                    anonType->setPrimitiveType(primitiveType);
+
+                    complexType->contentType()->setSimpleType(anonType);
+
+                    m_schema->addAnonymousType(anonType);
+                    m_componentLocationHash.insert(anonType, m_componentLocationHash.value(complexType));
+                }
+            } else if (complexBaseType->derivationMethod() == XsdComplexType::DerivationExtension) { // 3
+                complexType->contentType()->setSimpleType(complexBaseType->contentType()->simpleType());
+            }
+        } else if (complexBaseType->contentType()->variety() == XsdComplexType::ContentType::Mixed &&
+                   complexType->derivationMethod() == XsdComplexType::DerivationRestriction &&
+                   XsdSchemaHelper::isParticleEmptiable(complexBaseType->contentType()->particle())) { // 2
+            // simple type was already set in parser
+
+            const XsdSimpleType::Ptr anonType(new XsdSimpleType());
+            anonType->setCategory(complexType->contentType()->simpleType()->category());
+            anonType->setDerivationMethod(XsdSimpleType::DerivationRestriction);
+            anonType->setWxsSuperType(complexType->contentType()->simpleType());
+            anonType->setFacets(complexTypeFacets(complexType));
+
+            QSet<AnySimpleType::Ptr> visitedPrimitiveTypes;
+            const AnySimpleType::Ptr primitiveType = findPrimitiveType(anonType->wxsSuperType(), visitedPrimitiveTypes);
+            anonType->setPrimitiveType(primitiveType);
+
+            complexType->contentType()->setSimpleType(anonType);
+
+            m_schema->addAnonymousType(anonType);
+            m_componentLocationHash.insert(anonType, m_componentLocationHash.value(complexType));
+        } else {
+            complexType->contentType()->setSimpleType(BuiltinTypes::xsAnySimpleType);
+        }
+    } else if (baseType->isSimpleType()) { // 4
+        complexType->contentType()->setSimpleType(baseType);
+    } else { // 5
+        complexType->contentType()->setSimpleType(BuiltinTypes::xsAnySimpleType);
+    }
+}
+
+void XsdSchemaResolver::resolveComplexContentComplexTypes()
+{
+    XsdComplexType::List complexTypes;
+
+    // first collect the global complex types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (types.at(i)->isComplexType() && types.at(i)->isDefinedBySchema())
+            complexTypes.append(types.at(i));
+    }
+
+    // then collect all anonymous simple types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (anonymousTypes.at(i)->isComplexType() && anonymousTypes.at(i)->isDefinedBySchema())
+            complexTypes.append(anonymousTypes.at(i));
+    }
+
+    QSet<XsdComplexType::Ptr> visitedTypes;
+    for (int i = 0; i < complexTypes.count(); ++i) {
+        if (XsdComplexType::Ptr(complexTypes.at(i))->contentType()->variety() != XsdComplexType::ContentType::Simple)
+            resolveComplexContentComplexTypes(complexTypes.at(i), visitedTypes);
+    }
+}
+
+void XsdSchemaResolver::resolveComplexContentComplexTypes(const XsdComplexType::Ptr &complexType, QSet<XsdComplexType::Ptr> &visitedTypes)
+{
+    if (visitedTypes.contains(complexType))
+        return;
+    else
+        visitedTypes.insert(complexType);
+
+    ComplexContentType item;
+    bool foundCorrespondingItem = false;
+    for (int i = 0; i < m_complexContentTypes.count(); ++i) {
+        if (m_complexContentTypes.at(i).complexType == complexType) {
+            item = m_complexContentTypes.at(i);
+            foundCorrespondingItem = true;
+            break;
+        }
+    }
+
+    if (!foundCorrespondingItem)
+        return;
+
+    const SchemaType::Ptr baseType = complexType->wxsSuperType();
+
+    // at this point simple types have been resolved already, so we care about
+    // complex types here only
+    if (baseType->isComplexType() && baseType->isDefinedBySchema())
+        resolveComplexContentComplexTypes(XsdComplexType::Ptr(baseType), visitedTypes);
+
+
+    // @see http://www.w3.org/TR/xmlschema11-1/#dcl.ctd.ctcc.common
+
+    // 3
+    XsdParticle::Ptr effectiveContent;
+    if (!item.explicitContent) { // 3.1
+        if (item.effectiveMixed == true) { // 3.1.1
+            const XsdParticle::Ptr particle(new XsdParticle());
+            particle->setMinimumOccurs(1);
+            particle->setMaximumOccurs(1);
+            particle->setMaximumOccursUnbounded(false);
+
+            const XsdModelGroup::Ptr sequence(new XsdModelGroup());
+            sequence->setCompositor(XsdModelGroup::SequenceCompositor);
+            particle->setTerm(sequence);
+
+            effectiveContent = particle;
+        } else { // 3.1.2
+            effectiveContent = XsdParticle::Ptr();
+        }
+    } else { // 3.2
+        effectiveContent = item.explicitContent;
+    }
+
+    // 4
+    XsdComplexType::ContentType::Ptr explicitContentType(new XsdComplexType::ContentType());
+    if (item.complexType->derivationMethod() == XsdComplexType::DerivationRestriction) { // 4.1
+        if (!effectiveContent) { // 4.1.1
+            explicitContentType->setVariety(XsdComplexType::ContentType::Empty);
+        } else { // 4.1.2
+            if (item.effectiveMixed == true)
+                explicitContentType->setVariety(XsdComplexType::ContentType::Mixed);
+            else
+                explicitContentType->setVariety(XsdComplexType::ContentType::ElementOnly);
+
+            explicitContentType->setParticle(effectiveContent);
+        }
+    } else if (item.complexType->derivationMethod() == XsdComplexType::DerivationExtension) { // 4.2
+        const SchemaType::Ptr baseType = item.complexType->wxsSuperType();
+        if (baseType->isSimpleType() || (baseType->isComplexType() && baseType->isDefinedBySchema() && (XsdComplexType::Ptr(baseType)->contentType()->variety() == XsdComplexType::ContentType::Empty ||
+                                                                                                        XsdComplexType::Ptr(baseType)->contentType()->variety() == XsdComplexType::ContentType::Simple))) { // 4.2.1
+            if (!effectiveContent) {
+                explicitContentType->setVariety(XsdComplexType::ContentType::Empty);
+            } else {
+                if (item.effectiveMixed == true)
+                    explicitContentType->setVariety(XsdComplexType::ContentType::Mixed);
+                else
+                    explicitContentType->setVariety(XsdComplexType::ContentType::ElementOnly);
+
+                explicitContentType->setParticle(effectiveContent);
+            }
+        } else if (baseType->isComplexType() && baseType->isDefinedBySchema() && (XsdComplexType::Ptr(baseType)->contentType()->variety() == XsdComplexType::ContentType::ElementOnly ||
+                                                 XsdComplexType::Ptr(baseType)->contentType()->variety() == XsdComplexType::ContentType::Mixed) && !effectiveContent) { // 4.2.2
+            const XsdComplexType::Ptr complexBaseType(baseType);
+
+            explicitContentType = complexBaseType->contentType();
+        } else { // 4.2.3
+            explicitContentType->setVariety(item.effectiveMixed ? XsdComplexType::ContentType::Mixed : XsdComplexType::ContentType::ElementOnly);
+
+            XsdParticle::Ptr baseParticle;
+            if (baseType == BuiltinTypes::xsAnyType) {
+                // we need a workaround here, since the xsAnyType is no real (aka XsdComplexType) complex type...
+
+                baseParticle = XsdParticle::Ptr(new XsdParticle());
+                baseParticle->setMinimumOccurs(1);
+                baseParticle->setMaximumOccurs(1);
+                baseParticle->setMaximumOccursUnbounded(false);
+
+                const XsdModelGroup::Ptr group(new XsdModelGroup());
+                group->setCompositor(XsdModelGroup::SequenceCompositor);
+
+                const XsdParticle::Ptr particle(new XsdParticle());
+                particle->setMinimumOccurs(0);
+                particle->setMaximumOccursUnbounded(true);
+
+                const XsdWildcard::Ptr wildcard(new XsdWildcard());
+                wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Any);
+                wildcard->setProcessContents(XsdWildcard::Lax);
+
+                particle->setTerm(wildcard);
+                XsdParticle::List particles;
+                particles.append(particle);
+                group->setParticles(particles);
+                baseParticle->setTerm(group);
+            } else {
+                const XsdComplexType::Ptr complexBaseType(baseType);
+                baseParticle = complexBaseType->contentType()->particle();
+            }
+            if (baseParticle && baseParticle->term()->isModelGroup() && (XsdModelGroup::Ptr(baseParticle->term())->compositor() == XsdModelGroup::AllCompositor) &&
+                (!item.explicitContent)) { // 4.2.3.1
+
+                explicitContentType->setParticle(baseParticle);
+            } else if (baseParticle && baseParticle->term()->isModelGroup() && (XsdModelGroup::Ptr(baseParticle->term())->compositor() == XsdModelGroup::AllCompositor) &&
+                       (effectiveContent->term()->isModelGroup() && (XsdModelGroup::Ptr(effectiveContent->term())->compositor() == XsdModelGroup::AllCompositor))) { // 4.2.3.2
+                const XsdParticle::Ptr particle(new XsdParticle());
+                particle->setMinimumOccurs(effectiveContent->minimumOccurs());
+                particle->setMaximumOccurs(1);
+                particle->setMaximumOccursUnbounded(false);
+
+                const XsdModelGroup::Ptr group(new XsdModelGroup());
+                group->setCompositor(XsdModelGroup::AllCompositor);
+                XsdParticle::List particles = XsdModelGroup::Ptr(baseParticle->term())->particles();
+                particles << XsdModelGroup::Ptr(effectiveContent->term())->particles();
+                group->setParticles(particles);
+                particle->setTerm(group);
+
+                explicitContentType->setParticle(particle);
+            } else { // 4.2.3.3
+                const XsdParticle::Ptr particle(new XsdParticle());
+                particle->setMinimumOccurs(1);
+                particle->setMaximumOccurs(1);
+                particle->setMaximumOccursUnbounded(false);
+
+                const XsdModelGroup::Ptr group(new XsdModelGroup());
+                group->setCompositor(XsdModelGroup::SequenceCompositor);
+
+                if (effectiveContent && effectiveContent->term()->isModelGroup() && XsdModelGroup::Ptr(effectiveContent->term())->compositor() == XsdModelGroup::AllCompositor) {
+                    m_context->error(QtXmlPatterns::tr("Content model of complex type %1 contains %2 element so it cannot be derived by extension from a non-empty type.")
+                                                      .arg(formatType(m_namePool, complexType)).arg(formatKeyword("all")), XsdSchemaContext::XSDError, sourceLocation(complexType));
+                    return;
+                }
+
+                if (baseParticle && baseParticle->term()->isModelGroup() && XsdModelGroup::Ptr(baseParticle->term())->compositor() == XsdModelGroup::AllCompositor) {
+                    m_context->error(QtXmlPatterns::tr("Complex type %1 cannot be derived by extension from %2 as the latter contains %3 element in its content model.")
+                                                      .arg(formatType(m_namePool, complexType))
+                                                      .arg(formatType(m_namePool, baseType))
+                                                      .arg(formatKeyword("all")), XsdSchemaContext::XSDError, sourceLocation(complexType));
+                    return;
+                }
+
+                XsdParticle::List particles;
+                if (baseParticle)
+                    particles << baseParticle;
+                if (effectiveContent)
+                    particles << effectiveContent;
+                group->setParticles(particles);
+                particle->setTerm(group);
+
+                explicitContentType->setParticle(particle);
+            }
+
+            if (baseType->isDefinedBySchema()) { // xs:anyType has no open content
+                const XsdComplexType::Ptr complexBaseType(baseType);
+                explicitContentType->setOpenContent(complexBaseType->contentType()->openContent());
+            }
+        }
+    }
+
+    // 5
+    XsdComplexType::OpenContent::Ptr wildcardElement;
+    if (item.complexType->contentType()->openContent()) { // 5.1
+        wildcardElement = item.complexType->contentType()->openContent();
+    } else {
+        if (m_defaultOpenContent) { // 5.2
+            if ((explicitContentType->variety() != XsdComplexType::ContentType::Empty) || // 5.2.1
+                (explicitContentType->variety() == XsdComplexType::ContentType::Empty && m_defaultOpenContentAppliesToEmpty)) { // 5.2.2
+                wildcardElement = m_defaultOpenContent;
+            }
+        }
+    }
+
+    // 6
+    if (!wildcardElement) { // 6.1
+        item.complexType->setContentType(explicitContentType);
+    } else {
+        if (wildcardElement->mode() == XsdComplexType::OpenContent::None) { // 6.2
+            const XsdComplexType::ContentType::Ptr contentType(new XsdComplexType::ContentType());
+            contentType->setVariety(explicitContentType->variety());
+            contentType->setParticle(explicitContentType->particle());
+
+            item.complexType->setContentType(contentType);
+        } else { // 6.3
+            const XsdComplexType::ContentType::Ptr contentType(new XsdComplexType::ContentType());
+
+            if (explicitContentType->variety() == XsdComplexType::ContentType::Empty)
+                contentType->setVariety(XsdComplexType::ContentType::ElementOnly);
+            else
+                contentType->setVariety(explicitContentType->variety());
+
+            if (explicitContentType->variety() == XsdComplexType::ContentType::Empty) {
+                const XsdParticle::Ptr particle(new XsdParticle());
+                particle->setMinimumOccurs(1);
+                particle->setMaximumOccurs(1);
+                const XsdModelGroup::Ptr sequence(new XsdModelGroup());
+                sequence->setCompositor(XsdModelGroup::SequenceCompositor);
+                particle->setTerm(sequence);
+                contentType->setParticle(particle);
+            } else {
+                contentType->setParticle(explicitContentType->particle());
+            }
+
+            const XsdComplexType::OpenContent::Ptr openContent(new XsdComplexType::OpenContent());
+            if (wildcardElement)
+                openContent->setMode(wildcardElement->mode());
+            else
+                openContent->setMode(XsdComplexType::OpenContent::Interleave);
+
+            if (wildcardElement)
+                openContent->setWildcard(wildcardElement->wildcard());
+
+            item.complexType->setContentType(contentType);
+        }
+    }
+}
+
+void XsdSchemaResolver::resolveAttributeTypes()
+{
+    for (int i = 0; i < m_attributeTypes.count(); ++i) {
+        const AttributeType item = m_attributeTypes.at(i);
+
+        SchemaType::Ptr type = m_schema->type(item.typeName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.typeName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Type %1 of %2 element cannot be resolved.")
+                                                  .arg(formatType(m_namePool, item.typeName))
+                                                  .arg(formatElement("attribute")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        if (!type->isSimpleType() && type->category() != SchemaType::None) {
+            m_context->error(QtXmlPatterns::tr("Type of %1 element must be a simple type, %2 is not.")
+                                              .arg(formatElement("attribute"))
+                                              .arg(formatType(m_namePool, item.typeName)),
+                             XsdSchemaContext::XSDError, item.location);
+            return;
+        }
+
+        item.attribute->setType(type);
+    }
+}
+
+void XsdSchemaResolver::resolveAlternativeTypes()
+{
+    for (int i = 0; i < m_alternativeTypes.count(); ++i) {
+        const AlternativeType item = m_alternativeTypes.at(i);
+
+        SchemaType::Ptr type = m_schema->type(item.typeName);
+        if (!type) {
+            // maybe it's a basic type...
+            type = m_context->schemaTypeFactory()->createSchemaType(item.typeName);
+            if (!type) {
+                m_context->error(QtXmlPatterns::tr("Type %1 of %2 element cannot be resolved.")
+                                                  .arg(formatType(m_namePool, item.typeName))
+                                                  .arg(formatElement("alternative")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+        }
+
+        item.alternative->setType(type);
+    }
+
+    for (int i = 0; i < m_alternativeTypeElements.count(); ++i) {
+        const AlternativeTypeElement item = m_alternativeTypeElements.at(i);
+        item.alternative->setType(item.element->type());
+    }
+}
+
+bool hasCircularSubstitutionGroup(const XsdElement::Ptr &current, const XsdElement::Ptr &head, const NamePool::Ptr &namePool)
+{
+    if (current == head)
+        return true;
+    else {
+        const XsdElement::List elements = current->substitutionGroupAffiliations();
+        for (int i = 0; i < elements.count(); ++i) {
+            if (hasCircularSubstitutionGroup(elements.at(i), head, namePool))
+                return true;
+        }
+    }
+
+    return false;
+}
+
+void XsdSchemaResolver::resolveSubstitutionGroupAffiliations()
+{
+    for (int i = 0; i < m_substitutionGroupAffiliations.count(); ++i) {
+        const SubstitutionGroupAffiliation item = m_substitutionGroupAffiliations.at(i);
+
+        XsdElement::List affiliations;
+        for (int j = 0; j < item.elementNames.count(); ++j) {
+            const XsdElement::Ptr element = m_schema->element(item.elementNames.at(j));
+            if (!element) {
+                m_context->error(QtXmlPatterns::tr("Substitution group %1 of %2 element cannot be resolved.")
+                                                  .arg(formatKeyword(m_namePool, item.elementNames.at(j)))
+                                                  .arg(formatElement("element")),
+                                 XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+
+            // @see http://www.w3.org/TR/xmlschema11-1/#e-props-correct 5)
+            if (hasCircularSubstitutionGroup(element, item.element, m_namePool)) {
+                m_context->error(QtXmlPatterns::tr("Substitution group %1 has circular definition.").arg(formatKeyword(m_namePool, item.elementNames.at(j))), XsdSchemaContext::XSDError, item.location);
+                return;
+            }
+
+            affiliations.append(element);
+        }
+
+        item.element->setSubstitutionGroupAffiliations(affiliations);
+    }
+
+    for (int i = 0; i < m_substitutionGroupTypes.count(); ++i) {
+        const XsdElement::Ptr element = m_substitutionGroupTypes.at(i);
+        element->setType(element->substitutionGroupAffiliations().first()->type());
+    }
+}
+
+bool isSubstGroupHeadOf(const XsdElement::Ptr &head, const XsdElement::Ptr &element, const NamePool::Ptr &namePool)
+{
+    if (head->name(namePool) == element->name(namePool))
+        return true;
+
+    const XsdElement::List affiliations = element->substitutionGroupAffiliations();
+    for (int i = 0; i < affiliations.count(); ++i) {
+        if (isSubstGroupHeadOf(head, affiliations.at(i), namePool))
+            return true;
+    }
+
+    return false;
+}
+
+void XsdSchemaResolver::resolveSubstitutionGroups()
+{
+    const XsdElement::List elements = m_schema->elements();
+    for (int i = 0; i < elements.count(); ++i) {
+        const XsdElement::Ptr element = elements.at(i);
+
+        // the element is always itself in the substitution group
+        element->addSubstitutionGroup(element);
+
+        for (int j = 0; j < elements.count(); ++j) {
+            if (i == j)
+                continue;
+
+            if (isSubstGroupHeadOf(element, elements.at(j), m_namePool))
+                element->addSubstitutionGroup(elements.at(j));
+        }
+    }
+}
+
+void XsdSchemaResolver::resolveTermReferences()
+{
+    // first the global complex types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (!(types.at(i)->isComplexType()) || !types.at(i)->isDefinedBySchema())
+            continue;
+
+        const XsdComplexType::Ptr complexType = types.at(i);
+        if (complexType->contentType()->variety() != XsdComplexType::ContentType::ElementOnly && complexType->contentType()->variety() != XsdComplexType::ContentType::Mixed)
+            continue;
+
+        resolveTermReference(complexType->contentType()->particle(), QSet<QXmlName>());
+    }
+
+    // then all anonymous complex types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (!(anonymousTypes.at(i)->isComplexType()) || !anonymousTypes.at(i)->isDefinedBySchema())
+            continue;
+
+        const XsdComplexType::Ptr complexType = anonymousTypes.at(i);
+        if (complexType->contentType()->variety() != XsdComplexType::ContentType::ElementOnly && complexType->contentType()->variety() != XsdComplexType::ContentType::Mixed)
+            continue;
+
+        resolveTermReference(complexType->contentType()->particle(), QSet<QXmlName>());
+    }
+
+    const XsdModelGroup::List groups = m_schema->elementGroups();
+    for (int i = 0; i < groups.count(); ++i) {
+        const XsdParticle::Ptr particle(new XsdParticle());
+        particle->setTerm(groups.at(i));
+        resolveTermReference(particle, QSet<QXmlName>());
+    }
+}
+
+void XsdSchemaResolver::resolveTermReference(const XsdParticle::Ptr &particle, QSet<QXmlName> visitedGroups)
+{
+    if (!particle)
+        return;
+
+    const XsdTerm::Ptr term = particle->term();
+
+    // if it is a model group, we iterate over it recursive...
+    if (term->isModelGroup()) {
+        const XsdModelGroup::Ptr modelGroup = term;
+        const XsdParticle::List particles = modelGroup->particles();
+
+        for (int i = 0; i < particles.count(); ++i) {
+            resolveTermReference(particles.at(i), visitedGroups);
+        }
+
+        // check for unique names of elements inside all compositor
+        if (modelGroup->compositor() != XsdModelGroup::ChoiceCompositor) {
+            for (int i = 0; i < particles.count(); ++i) {
+                const XsdParticle::Ptr particle = particles.at(i);
+                const XsdTerm::Ptr term = particle->term();
+
+                if (!(term->isElement()))
+                    continue;
+
+                for (int j = 0; j < particles.count(); ++j) {
+                    const XsdParticle::Ptr otherParticle = particles.at(j);
+                    const XsdTerm::Ptr otherTerm = otherParticle->term();
+
+                    if (otherTerm->isElement() && i != j) {
+                        const XsdElement::Ptr element = term;
+                        const XsdElement::Ptr otherElement = otherTerm;
+
+                        if (element->name(m_namePool) == otherElement->name(m_namePool)) {
+                            if (modelGroup->compositor() == XsdModelGroup::AllCompositor) {
+                                m_context->error(QtXmlPatterns::tr("Duplicated element names %1 in %2 element.")
+                                                                  .arg(formatKeyword(element->displayName(m_namePool)))
+                                                                  .arg(formatElement("all")),
+                                                 XsdSchemaContext::XSDError, sourceLocation(modelGroup));
+                                return;
+                            } else if (modelGroup->compositor() == XsdModelGroup::SequenceCompositor) {
+                                if (element->type() != otherElement->type()) {  // not same variety
+                                    m_context->error(QtXmlPatterns::tr("Duplicated element names %1 in %2 element.")
+                                                                      .arg(formatKeyword(element->displayName(m_namePool)))
+                                                                      .arg(formatElement("sequence")),
+                                                     XsdSchemaContext::XSDError, sourceLocation(modelGroup));
+                                    return;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        return;
+    }
+
+    // ...otherwise we have reached the end of recursion...
+    if (!term->isReference())
+        return;
+
+    // ...or we have reached a reference term that must be resolved
+    const XsdReference::Ptr reference = term;
+    switch (reference->type()) {
+        case XsdReference::Element:
+                {
+                    const XsdElement::Ptr element = m_schema->element(reference->referenceName());
+                    if (element) {
+                        particle->setTerm(element);
+                    } else {
+                        m_context->error(QtXmlPatterns::tr("Reference %1 of %2 element cannot be resolved.")
+                                                          .arg(formatKeyword(m_namePool, reference->referenceName()))
+                                                          .arg(formatElement("element")),
+                                         XsdSchemaContext::XSDError, reference->sourceLocation());
+                        return;
+                    }
+                }
+            break;
+        case XsdReference::ModelGroup:
+                {
+                    const XsdModelGroup::Ptr modelGroup = m_schema->elementGroup(reference->referenceName());
+                    if (modelGroup) {
+                        if (visitedGroups.contains(modelGroup->name(m_namePool))) {
+                            m_context->error(QtXmlPatterns::tr("Circular group reference for %1.").arg(formatKeyword(modelGroup->displayName(m_namePool))),
+                                             XsdSchemaContext::XSDError, reference->sourceLocation());
+                        } else {
+                            visitedGroups.insert(modelGroup->name(m_namePool));
+                        }
+
+                        particle->setTerm(modelGroup);
+
+                        // start recursive iteration here as well to get all references resolved
+                        const XsdParticle::List particles = modelGroup->particles();
+                        for (int i = 0; i < particles.count(); ++i) {
+                            resolveTermReference(particles.at(i), visitedGroups);
+                        }
+
+                        if (modelGroup->compositor() == XsdModelGroup::AllCompositor) {
+                            if (m_allGroups.contains(reference)) {
+                                m_context->error(QtXmlPatterns::tr("%1 element is not allowed in this scope").arg(formatElement("all.")),
+                                                 XsdSchemaContext::XSDError, reference->sourceLocation());
+                                return;
+                            }
+                            if (particle->maximumOccursUnbounded() || particle->maximumOccurs() != 1) {
+                                m_context->error(QtXmlPatterns::tr("%1 element cannot have %2 attribute with value other than %3.")
+                                                                  .arg(formatElement("all"))
+                                                                  .arg(formatAttribute("maxOccurs"))
+                                                                  .arg(formatData("1")),
+                                                 XsdSchemaContext::XSDError, reference->sourceLocation());
+                                return;
+                            }
+                            if (particle->minimumOccurs() != 0 && particle->minimumOccurs() != 1) {
+                                m_context->error(QtXmlPatterns::tr("%1 element cannot have %2 attribute with value other than %3 or %4.")
+                                                                  .arg(formatElement("all"))
+                                                                  .arg(formatAttribute("minOccurs"))
+                                                                  .arg(formatData("0"))
+                                                                  .arg(formatData("1")),
+                                                 XsdSchemaContext::XSDError, reference->sourceLocation());
+                                return;
+                            }
+                        }
+                    } else {
+                        m_context->error(QtXmlPatterns::tr("Reference %1 of %2 element cannot be resolved.")
+                                                          .arg(formatKeyword(m_namePool, reference->referenceName()))
+                                                          .arg(formatElement("group")),
+                                         XsdSchemaContext::XSDError, reference->sourceLocation());
+                        return;
+                    }
+                }
+            break;
+    }
+}
+
+void XsdSchemaResolver::resolveAttributeTermReferences()
+{
+    // first all global attribute groups
+    const XsdAttributeGroup::List attributeGroups = m_schema->attributeGroups();
+    for (int i = 0; i < attributeGroups.count(); ++i) {
+        XsdWildcard::Ptr wildcard = attributeGroups.at(i)->wildcard();
+        const XsdAttributeUse::List uses = resolveAttributeTermReferences(attributeGroups.at(i)->attributeUses(), wildcard, QSet<QXmlName>());
+        attributeGroups.at(i)->setAttributeUses(uses);
+        attributeGroups.at(i)->setWildcard(wildcard);
+    }
+
+    // then the global complex types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (!(types.at(i)->isComplexType()) || !types.at(i)->isDefinedBySchema())
+            continue;
+
+        const XsdComplexType::Ptr complexType = types.at(i);
+        const XsdAttributeUse::List attributeUses = complexType->attributeUses();
+
+        XsdWildcard::Ptr wildcard = complexType->attributeWildcard();
+        const XsdAttributeUse::List uses = resolveAttributeTermReferences(attributeUses, wildcard, QSet<QXmlName>());
+        complexType->setAttributeUses(uses);
+        complexType->setAttributeWildcard(wildcard);
+    }
+
+    // and afterwards all anonymous complex types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (!(anonymousTypes.at(i)->isComplexType()) || !anonymousTypes.at(i)->isDefinedBySchema())
+            continue;
+
+        const XsdComplexType::Ptr complexType = anonymousTypes.at(i);
+        const XsdAttributeUse::List attributeUses = complexType->attributeUses();
+
+        XsdWildcard::Ptr wildcard = complexType->attributeWildcard();
+        const XsdAttributeUse::List uses = resolveAttributeTermReferences(attributeUses, wildcard, QSet<QXmlName>());
+        complexType->setAttributeUses(uses);
+        complexType->setAttributeWildcard(wildcard);
+    }
+}
+
+XsdAttributeUse::List XsdSchemaResolver::resolveAttributeTermReferences(const XsdAttributeUse::List &attributeUses, XsdWildcard::Ptr &wildcard, QSet<QXmlName> visitedAttributeGroups)
+{
+    XsdAttributeUse::List resolvedAttributeUses;
+
+    for (int i = 0; i < attributeUses.count(); ++i) {
+        const XsdAttributeUse::Ptr attributeUse = attributeUses.at(i);
+        if (attributeUse->isAttributeUse()) {
+            // it is a real attribute use, so no need to resolve it
+            resolvedAttributeUses.append(attributeUse);
+        } else if (attributeUse->isReference()) {
+            // it is just a reference, so resolve it to the real attribute use
+
+            const XsdAttributeReference::Ptr reference = attributeUse;
+            if (reference->type() == XsdAttributeReference::AttributeUse) {
+
+                // lookup the real attribute
+                const XsdAttribute::Ptr attribute = m_schema->attribute(reference->referenceName());
+                if (!attribute) {
+                    m_context->error(QtXmlPatterns::tr("Reference %1 of %2 element cannot be resolved.")
+                                                      .arg(formatKeyword(m_namePool, reference->referenceName()))
+                                                      .arg(formatElement("attribute")),
+                                     XsdSchemaContext::XSDError, reference->sourceLocation());
+                    return XsdAttributeUse::List();
+                }
+
+                // if both, reference and definition have a fixed or default value set, then they must be equal
+                if (attribute->valueConstraint() && attributeUse->valueConstraint()) {
+                    if (attribute->valueConstraint()->value() != attributeUse->valueConstraint()->value()) {
+                        m_context->error(QtXmlPatterns::tr("%1 or %2 attribute of reference %3 does not match with the attribute declaration %4.")
+                                                          .arg(formatAttribute("fixed"))
+                                                          .arg(formatAttribute("default"))
+                                                          .arg(formatKeyword(m_namePool, reference->referenceName()))
+                                                          .arg(formatKeyword(attribute->displayName(m_namePool))),
+                                         XsdSchemaContext::XSDError, reference->sourceLocation());
+                        return XsdAttributeUse::List();
+                    }
+                }
+
+                attributeUse->setAttribute(attribute);
+                if (!attributeUse->valueConstraint() && attribute->valueConstraint())
+                    attributeUse->setValueConstraint(XsdAttributeUse::ValueConstraint::fromAttributeValueConstraint(attribute->valueConstraint()));
+
+                resolvedAttributeUses.append(attributeUse);
+            } else if (reference->type() == XsdAttributeReference::AttributeGroup) {
+                const XsdAttributeGroup::Ptr attributeGroup = m_schema->attributeGroup(reference->referenceName());
+                if (!attributeGroup) {
+                    m_context->error(QtXmlPatterns::tr("Reference %1 of %2 element cannot be resolved.")
+                                                      .arg(formatKeyword(m_namePool, reference->referenceName()))
+                                                      .arg(formatElement("attributeGroup")),
+                                     XsdSchemaContext::XSDError, reference->sourceLocation());
+                    return XsdAttributeUse::List();
+                }
+                if (visitedAttributeGroups.contains(attributeGroup->name(m_namePool))) {
+                    m_context->error(QtXmlPatterns::tr("Attribute group %1 has circular reference.").arg(formatKeyword(m_namePool, reference->referenceName())),
+                                     XsdSchemaContext::XSDError, reference->sourceLocation());
+                    return XsdAttributeUse::List();
+                } else {
+                    visitedAttributeGroups.insert(attributeGroup->name(m_namePool));
+                }
+
+                // resolve attribute wildcards as defined in http://www.w3.org/TR/xmlschema11-1/#declare-attributeGroup-wildcard
+                XsdWildcard::Ptr childWildcard;
+                resolvedAttributeUses << resolveAttributeTermReferences(attributeGroup->attributeUses(), childWildcard, visitedAttributeGroups);
+                if (!childWildcard) {
+                    if (attributeGroup->wildcard()) {
+                        if (wildcard) {
+                            const XsdWildcard::ProcessContents contents = wildcard->processContents();
+                            wildcard = XsdSchemaHelper::wildcardIntersection(wildcard, attributeGroup->wildcard());
+                            wildcard->setProcessContents(contents);
+                        } else {
+                            wildcard = attributeGroup->wildcard();
+                        }
+                    }
+                } else {
+                    XsdWildcard::Ptr newWildcard;
+                    if (attributeGroup->wildcard()) {
+                        const XsdWildcard::ProcessContents contents = attributeGroup->wildcard()->processContents();
+                        newWildcard = XsdSchemaHelper::wildcardIntersection(attributeGroup->wildcard(), childWildcard);
+                        newWildcard->setProcessContents(contents);
+                    } else {
+                        newWildcard = childWildcard;
+                    }
+
+                    if (wildcard) {
+                        const XsdWildcard::ProcessContents contents = wildcard->processContents();
+                        wildcard = XsdSchemaHelper::wildcardIntersection(wildcard, newWildcard);
+                        wildcard->setProcessContents(contents);
+                    } else {
+                        wildcard = newWildcard;
+                    }
+                }
+            }
+        }
+    }
+
+    return resolvedAttributeUses;
+}
+
+void XsdSchemaResolver::resolveAttributeInheritance()
+{
+    // collect the global and anonymous complex types
+    SchemaType::List types = m_schema->types();
+    types << m_schema->anonymousTypes();
+
+    QSet<XsdComplexType::Ptr> visitedTypes;
+    for (int i = 0; i < types.count(); ++i) {
+        if (!(types.at(i)->isComplexType()) || !types.at(i)->isDefinedBySchema())
+            continue;
+
+        const XsdComplexType::Ptr complexType = types.at(i);
+
+        resolveAttributeInheritance(complexType, visitedTypes);
+    }
+}
+
+bool isValidWildcardRestriction(const XsdWildcard::Ptr &wildcard, const XsdWildcard::Ptr &baseWildcard)
+{
+    if (wildcard->namespaceConstraint()->variety() == baseWildcard->namespaceConstraint()->variety()) {
+        if (!XsdSchemaHelper::checkWildcardProcessContents(baseWildcard, wildcard))
+            return false;
+    }
+
+    if (wildcard->namespaceConstraint()->variety() == XsdWildcard::NamespaceConstraint::Any &&
+        baseWildcard->namespaceConstraint()->variety() != XsdWildcard::NamespaceConstraint::Any ) {
+        return false;
+    }
+    if (baseWildcard->namespaceConstraint()->variety() == XsdWildcard::NamespaceConstraint::Not &&
+        wildcard->namespaceConstraint()->variety() == XsdWildcard::NamespaceConstraint::Enumeration) {
+        if (!baseWildcard->namespaceConstraint()->namespaces().intersect(wildcard->namespaceConstraint()->namespaces()).isEmpty())
+            return false;
+    }
+    if (baseWildcard->namespaceConstraint()->variety() == XsdWildcard::NamespaceConstraint::Enumeration &&
+        wildcard->namespaceConstraint()->variety() == XsdWildcard::NamespaceConstraint::Enumeration) {
+        if (!wildcard->namespaceConstraint()->namespaces().subtract(baseWildcard->namespaceConstraint()->namespaces()).isEmpty())
+            return false;
+    }
+
+    return true;
+}
+
+/*
+ * Since we inherit the attributes from our base class we have to walk up in the
+ * inheritance hierarchy first and resolve the attribute inheritance top-down.
+ */
+void XsdSchemaResolver::resolveAttributeInheritance(const XsdComplexType::Ptr &complexType, QSet<XsdComplexType::Ptr> &visitedTypes)
+{
+    if (visitedTypes.contains(complexType))
+        return;
+    else
+        visitedTypes.insert(complexType);
+
+    const SchemaType::Ptr baseType = complexType->wxsSuperType();
+    Q_ASSERT(baseType);
+
+    if (!(baseType->isComplexType()) || !baseType->isDefinedBySchema())
+        return;
+
+    const XsdComplexType::Ptr complexBaseType = baseType;
+
+    resolveAttributeInheritance(complexBaseType, visitedTypes);
+
+    // @see http://www.w3.org/TR/xmlschema11-1/#dcl.ctd.attuses
+
+    // 1 and 2 (the attribute groups have been resolved here already)
+    const XsdAttributeUse::List uses = complexBaseType->attributeUses();
+
+    if (complexType->derivationMethod() == XsdComplexType::DerivationRestriction) { // 3.2
+        const XsdAttributeUse::List currentUses = complexType->attributeUses();
+
+        // 3.2.1 and 3.2.2 As we also keep the prohibited attributes as objects, the algorithm below
+        // handles both the same way
+
+        // add only these attribute uses of the base type that match one of the following criteria:
+        //   1: there is no attribute use with the same name in type
+        //   2: there is no attribute with the same name marked as prohibited in type
+        for (int j = 0; j < uses.count(); ++j) {
+            const XsdAttributeUse::Ptr use = uses.at(j);
+            bool found = false;
+            for (int k = 0; k < currentUses.count(); ++k) {
+                if (use->attribute()->name(m_namePool) == currentUses.at(k)->attribute()->name(m_namePool)) {
+                    found = true;
+
+                    // check if prohibited usage is violated
+                    if ((use->useType() == XsdAttributeUse::ProhibitedUse) && (currentUses.at(k)->useType() != XsdAttributeUse::ProhibitedUse)) {
+                        m_context->error(QtXmlPatterns::tr("%1 attribute in %2 must have %3 use like in base type %4.")
+                                                            .arg(formatAttribute(use->attribute()->displayName(m_namePool)))
+                                                            .arg(formatType(m_namePool, complexType))
+                                                            .arg(formatData("prohibited"))
+                                                            .arg(formatType(m_namePool, complexBaseType)),
+                                                             XsdSchemaContext::XSDError, sourceLocation(complexType));
+                        return;
+                    }
+
+                    break;
+                }
+            }
+
+            if (!found && uses.at(j)->useType() != XsdAttributeUse::ProhibitedUse) {
+                complexType->addAttributeUse(uses.at(j));
+            }
+        }
+    } else if (complexType->derivationMethod() == XsdComplexType::DerivationExtension) { // 3.1
+        QHash<QXmlName, XsdAttributeUse::Ptr> availableUses;
+
+        // fill hash with attribute uses of current type for faster lookup
+        {
+            const XsdAttributeUse::List attributeUses = complexType->attributeUses();
+
+            for (int i = 0; i < attributeUses.count(); ++i) {
+                availableUses.insert(attributeUses.at(i)->attribute()->name(m_namePool), attributeUses.at(i));
+            }
+        }
+
+        // just add the attribute uses of the base type
+        for (int i = 0; i < uses.count(); ++i) {
+            const XsdAttributeUse::Ptr currentAttributeUse = uses.at(i);
+
+            // if the base type defines the attribute as prohibited but we override it in current type, then don't copy the prohibited attribute use
+            if ((currentAttributeUse->useType() == XsdAttributeUse::ProhibitedUse) && availableUses.contains(currentAttributeUse->attribute()->name(m_namePool)))
+                continue;
+
+            complexType->addAttributeUse(uses.at(i));
+        }
+    }
+
+    // handle attribute wildcards: @see http://www.w3.org/TR/xmlschema11-1/#dcl.ctd.anyatt
+
+    // 1
+    const XsdWildcard::Ptr completeWildcard(complexType->attributeWildcard());
+
+    if (complexType->derivationMethod() == XsdComplexType::DerivationRestriction) {
+        if (complexType->wxsSuperType()->isComplexType() && complexType->wxsSuperType()->isDefinedBySchema()) {
+            const XsdComplexType::Ptr complexBaseType(complexType->wxsSuperType());
+            if (complexType->attributeWildcard()) {
+                if (complexBaseType->attributeWildcard()) {
+                    if (!isValidWildcardRestriction(complexType->attributeWildcard(), complexBaseType->attributeWildcard())) {
+                        m_context->error(QtXmlPatterns::tr("Attribute wildcard of %1 is not a valid restriction of attribute wildcard of base type %2.")
+                                                            .arg(formatType(m_namePool, complexType))
+                                                            .arg(formatType(m_namePool, complexBaseType)),
+                                                             XsdSchemaContext::XSDError, sourceLocation(complexType));
+                        return;
+                    }
+                } else {
+                    m_context->error(QtXmlPatterns::tr("%1 has attribute wildcard but its base type %2 has not.")
+                                                        .arg(formatType(m_namePool, complexType))
+                                                        .arg(formatType(m_namePool, complexBaseType)),
+                                                         XsdSchemaContext::XSDError, sourceLocation(complexType));
+                    return;
+                }
+            }
+        }
+        complexType->setAttributeWildcard(completeWildcard); // 2.1
+    } else if (complexType->derivationMethod() == XsdComplexType::DerivationExtension) {
+        XsdWildcard::Ptr baseWildcard; // 2.2.1
+        if (complexType->wxsSuperType()->isComplexType() && complexType->wxsSuperType()->isDefinedBySchema())
+            baseWildcard = XsdComplexType::Ptr(complexType->wxsSuperType())->attributeWildcard(); // 2.2.1.1
+        else
+            baseWildcard = XsdWildcard::Ptr(); // 2.2.1.2
+
+        if (!baseWildcard) {
+            complexType->setAttributeWildcard(completeWildcard); // 2.2.2.1
+        } else if (!completeWildcard) {
+            complexType->setAttributeWildcard(baseWildcard); // 2.2.2.2
+        } else {
+            XsdWildcard::Ptr unionWildcard = XsdSchemaHelper::wildcardUnion(completeWildcard, baseWildcard);
+            if (unionWildcard) {
+                unionWildcard->setProcessContents(completeWildcard->processContents());
+                complexType->setAttributeWildcard(unionWildcard); // 2.2.2.3
+            } else {
+                m_context->error(QtXmlPatterns::tr("Union of attribute wildcard of type %1 and attribute wildcard of its base type %2 is not expressible.")
+                                                    .arg(formatType(m_namePool, complexType))
+                                                    .arg(formatType(m_namePool, complexBaseType)),
+                                                     XsdSchemaContext::XSDError, sourceLocation(complexType));
+                return;
+            }
+        }
+    }
+}
+
+void XsdSchemaResolver::resolveEnumerationFacetValues()
+{
+    XsdSimpleType::List simpleTypes;
+
+    // first collect the global simple types
+    const SchemaType::List types = m_schema->types();
+    for (int i = 0; i < types.count(); ++i) {
+        if (types.at(i)->isSimpleType())
+            simpleTypes.append(types.at(i));
+    }
+
+    // then collect all anonymous simple types
+    const SchemaType::List anonymousTypes = m_schema->anonymousTypes();
+    for (int i = 0; i < anonymousTypes.count(); ++i) {
+        if (anonymousTypes.at(i)->isSimpleType())
+            simpleTypes.append(anonymousTypes.at(i));
+    }
+    // process all simple types
+    for (int i = 0; i < simpleTypes.count(); ++i) {
+        const XsdSimpleType::Ptr simpleType = simpleTypes.at(i);
+
+        // we resolve the enumeration values only for xs:QName and xs:NOTATION based types
+        if (BuiltinTypes::xsQName->wxsTypeMatches(simpleType) ||
+            BuiltinTypes::xsNOTATION->wxsTypeMatches(simpleType)) {
+            const XsdFacet::Hash facets = simpleType->facets();
+            if (facets.contains(XsdFacet::Enumeration)) {
+                AtomicValue::List newValues;
+
+                const XsdFacet::Ptr facet = facets.value(XsdFacet::Enumeration);
+                const AtomicValue::List values = facet->multiValue();
+                for (int j = 0; j < values.count(); ++j) {
+                    const AtomicValue::Ptr value = values.at(j);
+
+                    Q_ASSERT(m_enumerationFacetValues.contains(value));
+                    const NamespaceSupport support( m_enumerationFacetValues.value(value) );
+
+                    const QString qualifiedName = value->as<DerivedString<TypeString> >()->stringValue();
+                    if (!XPathHelper::isQName(qualifiedName)) {
+                        m_context->error(QtXmlPatterns::tr("Enumeration facet contains invalid content: {%1} is not a value of type %2.")
+                                                          .arg(formatData(qualifiedName))
+                                                          .arg(formatType(m_namePool, BuiltinTypes::xsQName)),
+                                         XsdSchemaContext::XSDError, sourceLocation(simpleType));
+                        return;
+                    }
+
+                    QXmlName qNameValue;
+                    bool result = support.processName(qualifiedName, NamespaceSupport::ElementName, qNameValue);
+                    if (!result) {
+                        m_context->error(QtXmlPatterns::tr("Namespace prefix of qualified name %1 is not defined.").arg(formatData(qualifiedName)),
+                                         XsdSchemaContext::XSDError, sourceLocation(simpleType));
+                        return;
+                    }
+
+                    newValues.append(QNameValue::fromValue(m_namePool, qNameValue));
+                }
+                facet->setMultiValue(newValues);
+            }
+        }
+    }
+}
+
+QSourceLocation XsdSchemaResolver::sourceLocation(const NamedSchemaComponent::Ptr component) const
+{
+    if (m_componentLocationHash.contains(component)) {
+        return m_componentLocationHash.value(component);
+    } else {
+        QSourceLocation location;
+        location.setLine(1);
+        location.setColumn(1);
+        location.setUri(QString::fromLatin1("dummyUri"));
+
+        return location;
+    }
+}
+
+XsdFacet::Hash XsdSchemaResolver::complexTypeFacets(const XsdComplexType::Ptr &complexType) const
+{
+    for (int i = 0; i < m_complexBaseTypes.count(); ++i) {
+        if (m_complexBaseTypes.at(i).complexType == complexType)
+            return m_complexBaseTypes.at(i).facets;
+    }
+
+    return XsdFacet::Hash();
+}
+
+void XsdSchemaResolver::checkRedefinedGroups()
+{
+    for (int i = 0; i < m_redefinedGroups.count(); ++i) {
+        const RedefinedGroups item = m_redefinedGroups.at(i);
+
+        // create dummy particles...
+        const XsdParticle::Ptr redefinedParticle(new XsdParticle());
+        redefinedParticle->setTerm(item.redefinedGroup);
+        const XsdParticle::Ptr particle(new XsdParticle());
+        particle->setTerm(item.group);
+
+        // so that we can pass them to XsdParticleChecker::subsumes()
+        QString errorMsg;
+        if (!XsdParticleChecker::subsumes(particle, redefinedParticle, m_context, errorMsg)) {
+            m_context->error(QtXmlPatterns::tr("%1 element %2 is not a valid restriction of the %3 element it redefines: %4.")
+                                              .arg(formatElement("group"))
+                                              .arg(formatData(item.redefinedGroup->displayName(m_namePool)))
+                                              .arg(formatElement("group"))
+                                              .arg(errorMsg),
+                             XsdSchemaContext::XSDError, sourceLocation(item.redefinedGroup));
+            return;
+        }
+    }
+}
+
+void XsdSchemaResolver::checkRedefinedAttributeGroups()
+{
+    for (int i = 0; i < m_redefinedAttributeGroups.count(); ++i) {
+        const RedefinedAttributeGroups item = m_redefinedAttributeGroups.at(i);
+
+        QString errorMsg;
+        if (!XsdSchemaHelper::isValidAttributeGroupRestriction(item.redefinedGroup, item.group, m_context, errorMsg)) {
+            m_context->error(QtXmlPatterns::tr("%1 element %2 is not a valid restriction of the %3 element it redefines: %4.")
+                                              .arg(formatElement("attributeGroup"))
+                                              .arg(formatData(item.redefinedGroup->displayName(m_namePool)))
+                                              .arg(formatElement("attributeGroup"))
+                                              .arg(errorMsg),
+                             XsdSchemaContext::XSDError, sourceLocation(item.redefinedGroup));
+            return;
+        }
+    }
+}
+
+AnySimpleType::Ptr XsdSchemaResolver::findPrimitiveType(const AnySimpleType::Ptr &type, QSet<AnySimpleType::Ptr> &visitedTypes)
+{
+    if (visitedTypes.contains(type)) {
+        // found invalid circular reference...
+        return AnySimpleType::Ptr();
+    } else {
+        visitedTypes.insert(type);
+    }
+
+    const QXmlName typeName = type->name(m_namePool);
+    if (typeName == BuiltinTypes::xsString->name(m_namePool) ||
+        typeName == BuiltinTypes::xsBoolean->name(m_namePool) ||
+        typeName == BuiltinTypes::xsFloat->name(m_namePool) ||
+        typeName == BuiltinTypes::xsDouble->name(m_namePool) ||
+        typeName == BuiltinTypes::xsDecimal->name(m_namePool) ||
+        typeName == BuiltinTypes::xsDuration->name(m_namePool) ||
+        typeName == BuiltinTypes::xsDateTime->name(m_namePool) ||
+        typeName == BuiltinTypes::xsTime->name(m_namePool) ||
+        typeName == BuiltinTypes::xsDate->name(m_namePool) ||
+        typeName == BuiltinTypes::xsGYearMonth->name(m_namePool) ||
+        typeName == BuiltinTypes::xsGYear->name(m_namePool) ||
+        typeName == BuiltinTypes::xsGMonthDay->name(m_namePool) ||
+        typeName == BuiltinTypes::xsGDay->name(m_namePool) ||
+        typeName == BuiltinTypes::xsGMonth->name(m_namePool) ||
+        typeName == BuiltinTypes::xsHexBinary->name(m_namePool) ||
+        typeName == BuiltinTypes::xsBase64Binary->name(m_namePool) ||
+        typeName == BuiltinTypes::xsAnyURI->name(m_namePool) ||
+        typeName == BuiltinTypes::xsQName->name(m_namePool) ||
+        typeName == BuiltinTypes::xsNOTATION->name(m_namePool) ||
+        typeName == BuiltinTypes::xsAnySimpleType->name(m_namePool))
+        return type;
+    else {
+        if (type->wxsSuperType())
+            return findPrimitiveType(type->wxsSuperType(), visitedTypes);
+        else {
+            return AnySimpleType::Ptr();
+        }
+    }
+}
+
+QT_END_NAMESPACE