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#include "qxsdschemaparser_p.h"

#include "private/qxmlutils_p.h"
#include "qacceltreeresourceloader_p.h"
#include "qautoptr_p.h"
#include "qboolean_p.h"
#include "qcommonnamespaces_p.h"
#include "qderivedinteger_p.h"
#include "qderivedstring_p.h"
#include "qqnamevalue_p.h"
#include "qxmlquery_p.h"
#include "qxpathhelper_p.h"
#include "qxsdattributereference_p.h"
#include "qxsdreference_p.h"
#include "qxsdschematoken_p.h"

#include <QtCore/QFile>
#include <QtXmlPatterns/QXmlQuery>

QT_BEGIN_NAMESPACE

/**
 * @page schema_overview Overview
 * @section structure_and_components Structure and Components
 *
 * The schema validator code consists of 4 major components
 *
 * <dl>
 *  <dt>The schema parser (QPatternist::XsdSchemaParser)</dt>
 *  <dd>This component parses a XML document that is supplied via a QIODevice. It creates
 *      a so called (incomplete) 'compiled schema', which is a representation of the XML Schema
 *      structure as C++ objects.
 *      As the parser is a streaming parser, it can't resolve references to types or elements/attributes
 *      in place, therefore it creates resolver tasks which are passed to the schema resolver component
 *      for resolving at a later point in time.
 *      The parser does furthermore the basic XML structure constraint checking, e.g. if all required
 *      attributes are available or the order of the elements is correct.</dd>
 *
 *  <dt>The schema resolver (QPatternist::XsdSchemaResolver)</dt>
 *  <dd>This component is activated after the schema parser component has been finished the parsing
 *      of all schemas. The resolver has been supplied with resolve tasks by the schema parser that
 *      it will resolve in this step now. Between working on the single resolver tasks, the resolver
 *      calls check methods from the schema checker component to make sure that some assertions are
 *      valid (e.g. no circular inheritance of types), so that the resolver can work without hassle.
 *      During resoving references to attribute or element groups it also checks for circular references
 *      of these groups.
 *      At the end of that phase we have a compiled schema that is fully resolved (not necessarily valid though).</dd>
 *
 *  <dt>The schema checker (QPatternist::XsdSchemaChecker)</dt>
 *  <dd>This component does all the schema constraint checking as given by the Schema specification.
 *      At the end of that phase we have fully resolved and valid compiled schema that can be used for validation
 *      of instance documents.</dd>
 *
 *  <dt>The validator (QPatternist::XsdValidatingInstanceReader)</dt>
 *  <dd>This component is responsible for validating a XML instance document, provided via a QIODevice, against
 *      a valid compiled schema.</dd>
 * </dl>
 *
 * @ingroup Patternist_schema
 */

using namespace QPatternist;

namespace QPatternist
{

/**
 * @short A helper class for automatically handling namespace scopes of elements.
 *
 * This class should be instantiated at the beginning of each parse XYZ method.
 */
class ElementNamespaceHandler
{
    public:
        /**
         * Creates a new element namespace handler object.
         *
         * It checks whether the @p parser is on the right @p tag and it creates a new namespace
         * context that contains the inherited and local namespace declarations.
         */
        ElementNamespaceHandler(const XsdSchemaToken::NodeName &tag, XsdSchemaParser *parser)
            : m_parser(parser)
        {
            Q_ASSERT(m_parser->isStartElement() && (XsdSchemaToken::toToken(m_parser->name()) == tag) && (XsdSchemaToken::toToken(m_parser->namespaceUri()) == XsdSchemaToken::XML_NS_SCHEMA_URI));
            Q_UNUSED(tag)
            m_parser->m_namespaceSupport.pushContext();
            m_parser->m_namespaceSupport.setPrefixes(m_parser->namespaceDeclarations());
        }

        /**
         * Destroys the element namespace handler object.
         *
         * It destroys the local namespace context.
         */
        ~ElementNamespaceHandler()
        {
            m_parser->m_namespaceSupport.popContext();
        }

    private:
        XsdSchemaParser *m_parser;
};

/**
 * A helper class that checks for the right occurrence of
 * xml tags with the help of a DFA.
 */
class TagValidationHandler
{
    public:
        TagValidationHandler(XsdTagScope::Type tag, XsdSchemaParser *parser, const NamePool::Ptr &namePool)
            : m_parser(parser), m_machine(namePool)
        {
            Q_ASSERT(m_parser->m_stateMachines.contains(tag));

            m_machine = m_parser->m_stateMachines.value(tag);
            m_machine.reset();
        }

        void validate(XsdSchemaToken::NodeName token)
        {
            if (token == XsdSchemaToken::NoKeyword) {
                const QList<XsdSchemaToken::NodeName> tokens = m_machine.possibleTransitions();

                QStringList elementNames;
                for (int i = 0; i < tokens.count(); ++i)
                    elementNames.append(formatElement(XsdSchemaToken::toString(tokens.at(i))));

                m_parser->error(QtXmlPatterns::tr("Can not process unknown element %1, expected elements are: %2.")
                                                 .arg(formatElement(m_parser->name().toString()))
                                                 .arg(elementNames.join(QLatin1String(", "))));
                return;
            }

            if (!m_machine.proceed(token)) {
                const QList<XsdSchemaToken::NodeName> tokens = m_machine.possibleTransitions();

                QStringList elementNames;
                for (int i = 0; i < tokens.count(); ++i)
                    elementNames.append(formatElement(XsdSchemaToken::toString(tokens.at(i))));

                m_parser->error(QtXmlPatterns::tr("Element %1 is not allowed in this scope, possible elements are: %2.")
                                                 .arg(formatElement(XsdSchemaToken::toString(token)))
                                                 .arg(elementNames.join(QLatin1String(", "))));
                return;
            }
        }

        void finalize() const
        {
            if (!m_machine.inEndState()) {
                const QList<XsdSchemaToken::NodeName> tokens = m_machine.possibleTransitions();

                QStringList elementNames;
                for (int i = 0; i < tokens.count(); ++i)
                    elementNames.append(formatElement(XsdSchemaToken::toString(tokens.at(i))));

                m_parser->error(QtXmlPatterns::tr("Child element is missing in that scope, possible child elements are: %1.")
                                                 .arg(elementNames.join(QLatin1String(", "))));
            }
        }

        private:
            XsdSchemaParser *m_parser;
            XsdStateMachine<XsdSchemaToken::NodeName> m_machine;
};

}

/**
 * Returns a list of all particles with group references that appear at any level of
 * the given unresolved @p group.
 */
static XsdParticle::List collectGroupRef(const XsdModelGroup::Ptr &group)
{
    XsdParticle::List refParticles;

    XsdParticle::List particles = group->particles();
    for (int i = 0; i < particles.count(); ++i) {
        if (particles.at(i)->term()->isReference()) {
            const XsdReference::Ptr reference(particles.at(i)->term());
            if (reference->type() == XsdReference::ModelGroup)
                refParticles.append(particles.at(i));
        }
        if (particles.at(i)->term()->isModelGroup()) {
            refParticles << collectGroupRef(XsdModelGroup::Ptr(particles.at(i)->term()));
        }
    }

    return refParticles;
}

/**
 * Helper function that works around the limited facilities of
 * QUrl/AnyURI::fromLexical to detect invalid URIs
 */
inline static bool isValidUri(const QString &string)
{
    // an empty URI points to the current document as defined in RFC 2396 (4.2)
    if (string.isEmpty())
        return true;

    // explicit check as that is not checked by the code below
    if (string.startsWith(QLatin1String("##")))
        return false;

    const AnyURI::Ptr uri = AnyURI::fromLexical(string);
    return (!(uri->hasError()));
}

XsdSchemaParser::XsdSchemaParser(const XsdSchemaContext::Ptr &context, const XsdSchemaParserContext::Ptr &parserContext, QIODevice *device)
    : MaintainingReader<XsdSchemaToken, XsdTagScope::Type>(parserContext->elementDescriptions(), QSet<XsdSchemaToken::NodeName>(), context, device)
    , m_context(context)
    , m_parserContext(parserContext)
    , m_namePool(m_parserContext->namePool())
    , m_namespaceSupport(m_namePool)
    , m_defaultOpenContentAppliesToEmpty(false)
{
    m_schema = m_parserContext->schema();
    m_schemaResolver = m_parserContext->resolver();
    m_idCache = XsdIdCache::Ptr(new XsdIdCache());

    setupStateMachines();
    setupBuiltinTypeNames();
}

void XsdSchemaParser::addIncludedSchemas(const NamespaceSet &schemas)
{
    m_includedSchemas += schemas;
}

void XsdSchemaParser::setIncludedSchemas(const NamespaceSet &schemas)
{
    m_includedSchemas = schemas;
}

void XsdSchemaParser::addImportedSchemas(const NamespaceSet &schemas)
{
    m_importedSchemas += schemas;
}

void XsdSchemaParser::setImportedSchemas(const NamespaceSet &schemas)
{
    m_importedSchemas = schemas;
}

void XsdSchemaParser::addRedefinedSchemas(const NamespaceSet &schemas)
{
    m_redefinedSchemas += schemas;
}

void XsdSchemaParser::setRedefinedSchemas(const NamespaceSet &schemas)
{
    m_redefinedSchemas = schemas;
}

void XsdSchemaParser::setTargetNamespace(const QString &targetNamespace)
{
    m_targetNamespace = targetNamespace;
}

void XsdSchemaParser::setTargetNamespaceExtended(const QString &targetNamespace)
{
    m_targetNamespace = targetNamespace;
    m_namespaceSupport.setTargetNamespace(m_namePool->allocateNamespace(m_targetNamespace));
}

void XsdSchemaParser::setDocumentURI(const QUrl &uri)
{
    m_documentURI = uri;

    // prevent to get included/imported/redefined twice
    m_includedSchemas.insert(uri);
    m_importedSchemas.insert(uri);
    m_redefinedSchemas.insert(uri);
}

QUrl XsdSchemaParser::documentURI() const
{
    return m_documentURI;
}

bool XsdSchemaParser::isAnyAttributeAllowed() const
{
    return false;
}

bool XsdSchemaParser::parse(ParserType parserType)
{
    m_componentLocationHash.clear();

    while (!atEnd()) {
        readNext();

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            if (isSchemaTag(XsdSchemaToken::Schema, token, namespaceToken)) {
                parseSchema(parserType);
            } else {
                error(QtXmlPatterns::tr("Document is not a XML schema."));
            }
        }
    }

    m_schemaResolver->addComponentLocationHash(m_componentLocationHash);
    m_schemaResolver->setDefaultOpenContent(m_defaultOpenContent, m_defaultOpenContentAppliesToEmpty);

    if (QXmlStreamReader::error() != QXmlStreamReader::NoError)
        error(errorString());

    return true;
}

void XsdSchemaParser::error(const QString &msg)
{
    MaintainingReader<XsdSchemaToken, XsdTagScope::Type>::error(msg, XsdSchemaContext::XSDError);
}

void XsdSchemaParser::attributeContentError(const char *attributeName, const char *elementName, const QString &value, const SchemaType::Ptr &type)
{
    if (type) {
        error(QtXmlPatterns::tr("%1 attribute of %2 element contains invalid content: {%3} is not a value of type %4.")
                               .arg(formatAttribute(attributeName))
                               .arg(formatElement(elementName))
                               .arg(formatData(value))
                               .arg(formatType(m_namePool, type)));
    } else {
        error(QtXmlPatterns::tr("%1 attribute of %2 element contains invalid content: {%3}.")
                               .arg(formatAttribute(attributeName))
                               .arg(formatElement(elementName))
                               .arg(formatData(value)));
    }
}

void XsdSchemaParser::parseSchema(ParserType parserType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Schema, this);

    validateElement(XsdTagScope::Schema);

    // parse attributes

    if (parserType == TopLevelParser) {
        if (hasAttribute(QString::fromLatin1("targetNamespace"))) {
            m_targetNamespace = readNamespaceAttribute(QString::fromLatin1("targetNamespace"), "schema");
        }
    } else if (parserType == IncludeParser) {
        // m_targetNamespace is set to the target namespace of the including schema at this point

        if (hasAttribute(QString::fromLatin1("targetNamespace"))) {
            const QString targetNamespace = readNamespaceAttribute(QString::fromLatin1("targetNamespace"), "schema");

            if (m_targetNamespace != targetNamespace) {
                error(QtXmlPatterns::tr("Target namespace %1 of included schema is different from the target namespace %2 as defined by the including schema.")
                                       .arg(formatURI(targetNamespace)).arg(formatURI(m_targetNamespace)));
                return;
            }
        }
    } else if (parserType == ImportParser) {
        // m_targetNamespace is set to the target namespace from the namespace attribute of the <import> tag at this point

        QString targetNamespace;
        if (hasAttribute(QString::fromLatin1("targetNamespace"))) {
            targetNamespace = readNamespaceAttribute(QString::fromLatin1("targetNamespace"), "schema");
        }

        if (m_targetNamespace != targetNamespace) {
            error(QtXmlPatterns::tr("Target namespace %1 of imported schema is different from the target namespace %2 as defined by the importing schema.")
                                   .arg(formatURI(targetNamespace)).arg(formatURI(m_targetNamespace)));
            return;
        }
    } else if (parserType == RedefineParser) {
        // m_targetNamespace is set to the target namespace of the redefining schema at this point

        if (hasAttribute(QString::fromLatin1("targetNamespace"))) {
            const QString targetNamespace = readNamespaceAttribute(QString::fromLatin1("targetNamespace"), "schema");

            if (m_targetNamespace != targetNamespace) {
                error(QtXmlPatterns::tr("Target namespace %1 of imported schema is different from the target namespace %2 as defined by the importing schema.")
                                       .arg(formatURI(targetNamespace)).arg(formatURI(m_targetNamespace)));
                return;
            }
        }
    }

    if (hasAttribute(QString::fromLatin1("attributeFormDefault"))) {
        const QString value = readAttribute(QString::fromLatin1("attributeFormDefault"));
        if (value != QString::fromLatin1("qualified") && value != QString::fromLatin1("unqualified")) {
            attributeContentError("attributeFormDefault", "schema", value);
            return;
        }

        m_attributeFormDefault = value;
    } else {
        m_attributeFormDefault = QString::fromLatin1("unqualified");
    }

    if (hasAttribute(QString::fromLatin1("elementFormDefault"))) {
        const QString value = readAttribute(QString::fromLatin1("elementFormDefault"));
        if (value != QString::fromLatin1("qualified") && value != QString::fromLatin1("unqualified")) {
            attributeContentError("elementFormDefault", "schema", value);
            return;
        }

        m_elementFormDefault = value;
    } else {
        m_elementFormDefault = QString::fromLatin1("unqualified");
    }

    if (hasAttribute(QString::fromLatin1("blockDefault"))) {
        const QString blockDefault = readAttribute(QString::fromLatin1("blockDefault"));
        const QStringList blockDefaultList = blockDefault.split(QLatin1Char(' '), QString::SkipEmptyParts);
        for (int i = 0; i < blockDefaultList.count(); ++i) {
            const QString value = blockDefaultList.at(i);
            if (value != QString::fromLatin1("#all") &&
                value != QString::fromLatin1("extension") &&
                value != QString::fromLatin1("restriction") &&
                value != QString::fromLatin1("substitution")) {
                attributeContentError("blockDefault", "schema", value);
                return;
            }
        }

        m_blockDefault = blockDefault;
    }

    if (hasAttribute(QString::fromLatin1("finalDefault"))) {
        const QString finalDefault = readAttribute(QString::fromLatin1("finalDefault"));
        const QStringList finalDefaultList = finalDefault.split(QLatin1Char(' '), QString::SkipEmptyParts);
        for (int i = 0; i < finalDefaultList.count(); ++i) {
            const QString value = finalDefaultList.at(i);
            if (value != QString::fromLatin1("#all") &&
                value != QString::fromLatin1("extension") &&
                value != QString::fromLatin1("restriction") &&
                value != QString::fromLatin1("list") &&
                value != QString::fromLatin1("union")) {
                attributeContentError("finalDefault", "schema", value);
                return;
            }
        }

        m_finalDefault = finalDefault;
    }

    if (hasAttribute(QString::fromLatin1("xpathDefaultNamespace"))) {
        const QString xpathDefaultNamespace = readAttribute(QString::fromLatin1("xpathDefaultNamespace"));
        if (xpathDefaultNamespace != QString::fromLatin1("##defaultNamespace") &&
            xpathDefaultNamespace != QString::fromLatin1("##targetNamespace") &&
            xpathDefaultNamespace != QString::fromLatin1("##local")) {
            if (!isValidUri(xpathDefaultNamespace)) {
                attributeContentError("xpathDefaultNamespace", "schema", xpathDefaultNamespace);
                return;
            }
        }
        m_xpathDefaultNamespace = xpathDefaultNamespace;
    } else {
        m_xpathDefaultNamespace = QString::fromLatin1("##local");
    }

    if (hasAttribute(QString::fromLatin1("defaultAttributes"))) {
        const QString attrGroupName = readQNameAttribute(QString::fromLatin1("defaultAttributes"), "schema");
        convertName(attrGroupName, NamespaceSupport::ElementName, m_defaultAttributes); // translate qualified name into QXmlName
    }

    if (hasAttribute(QString::fromLatin1("version"))) {
        const QString version = readAttribute(QString::fromLatin1("version"));
    }

    if (hasAttribute(CommonNamespaces::XML, QString::fromLatin1("lang"))) {
        const QString value = readAttribute(QString::fromLatin1("lang"), CommonNamespaces::XML);

        QRegExp exp(QString::fromLatin1("[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*"));
        if (!exp.exactMatch(value)) {
            attributeContentError("xml:lang", "schema", value);
            return;
        }
    }

    validateIdAttribute("schema");

    TagValidationHandler tagValidator(XsdTagScope::Schema, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Include, token, namespaceToken)) {
                parseInclude();
            } else if (isSchemaTag(XsdSchemaToken::Import, token, namespaceToken)) {
                parseImport();
            } else if (isSchemaTag(XsdSchemaToken::Redefine, token, namespaceToken)) {
                parseRedefine();
            } else if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                m_schema->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::DefaultOpenContent, token, namespaceToken)) {
                parseDefaultOpenContent();
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                const XsdSimpleType::Ptr type = parseGlobalSimpleType();
                addType(type);
            } else if (isSchemaTag(XsdSchemaToken::ComplexType, token, namespaceToken)) {
                const XsdComplexType::Ptr type = parseGlobalComplexType();
                addType(type);
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdModelGroup::Ptr group = parseNamedGroup();
                addElementGroup(group);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                XsdAttributeGroup::Ptr attributeGroup = parseNamedAttributeGroup();
                addAttributeGroup(attributeGroup);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdElement::Ptr element = parseGlobalElement();
                addElement(element);
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttribute::Ptr attribute = parseGlobalAttribute();
                addAttribute(attribute);
            } else if (isSchemaTag(XsdSchemaToken::Notation, token, namespaceToken)) {
                const XsdNotation::Ptr notation = parseNotation();
                addNotation(notation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    m_schema->setTargetNamespace(m_targetNamespace);
}

void XsdSchemaParser::parseInclude()
{
    Q_ASSERT(isStartElement() && XsdSchemaToken::toToken(name()) == XsdSchemaToken::Include &&
                                 XsdSchemaToken::toToken(namespaceUri()) == XsdSchemaToken::XML_NS_SCHEMA_URI);

    validateElement(XsdTagScope::Include);

    // parse attributes
    const QString schemaLocation = readAttribute(QString::fromLatin1("schemaLocation"));

    QUrl url(schemaLocation);
    if (url.isRelative()) {
        Q_ASSERT(m_documentURI.isValid());

        url = m_documentURI.resolved(url);
    }

    if (m_includedSchemas.contains(url)) {
        // we have included that file already, according to the schema spec we are
        // allowed to silently skip it.
    } else {
        m_includedSchemas.insert(url);

        const AutoPtr<QNetworkReply> reply(AccelTreeResourceLoader::load(url, m_context->networkAccessManager(),
                                                                         m_context, AccelTreeResourceLoader::ContinueOnError));
        if (reply) {
            // parse the included schema by a different parser but with the same context
            XsdSchemaParser parser(m_context, m_parserContext, reply.data());
            parser.setDocumentURI(url);
            parser.setTargetNamespaceExtended(m_targetNamespace);
            parser.setIncludedSchemas(m_includedSchemas);
            parser.setImportedSchemas(m_importedSchemas);
            parser.setRedefinedSchemas(m_redefinedSchemas);
            if (!parser.parse(XsdSchemaParser::IncludeParser)) {
                return;
            } else {
                // add indirectly loaded schemas to the list of already loaded ones
                addIncludedSchemas(parser.m_includedSchemas);
                addImportedSchemas(parser.m_importedSchemas);
                addRedefinedSchemas(parser.m_redefinedSchemas);
            }
        }
    }

    validateIdAttribute("include");

    TagValidationHandler tagValidator(XsdTagScope::Include, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                m_schema->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseImport()
{
    Q_ASSERT(isStartElement() && XsdSchemaToken::toToken(name()) == XsdSchemaToken::Import &&
                                 XsdSchemaToken::toToken(namespaceUri()) == XsdSchemaToken::XML_NS_SCHEMA_URI);

    validateElement(XsdTagScope::Import);

    // parse attributes
    QString importNamespace;
    if (hasAttribute(QString::fromLatin1("namespace"))) {
        importNamespace = readAttribute(QString::fromLatin1("namespace"));
        if (importNamespace == m_targetNamespace) {
            error(QtXmlPatterns::tr("%1 element is not allowed to have the same %2 attribute value as the target namespace %3.")
                                   .arg(formatElement("import"))
                                   .arg(formatAttribute("namespace"))
                                   .arg(formatURI(m_targetNamespace)));
            return;
        }
    } else {
        if (m_targetNamespace.isEmpty()) {
            error(QtXmlPatterns::tr("%1 element without %2 attribute is not allowed inside schema without target namespace.")
                                   .arg(formatElement("import"))
                                   .arg(formatAttribute("namespace")));
            return;
        }
    }

    if (hasAttribute(QString::fromLatin1("schemaLocation"))) {
        const QString schemaLocation = readAttribute(QString::fromLatin1("schemaLocation"));

        QUrl url(schemaLocation);
        if (url.isRelative()) {
            Q_ASSERT(m_documentURI.isValid());

            url = m_documentURI.resolved(url);
        }

        if (m_importedSchemas.contains(url)) {
            // we have imported that file already, according to the schema spec we are
            // allowed to silently skip it.
        } else {
            m_importedSchemas.insert(url);

            // as it is possible that well known schemas (e.g. XSD for XML) are only referenced by
            // namespace we should add it as well
            m_importedSchemas.insert(importNamespace);

            AutoPtr<QNetworkReply> reply(AccelTreeResourceLoader::load(url, m_context->networkAccessManager(),
                                                                       m_context, AccelTreeResourceLoader::ContinueOnError));
            if (reply) {
                // parse the included schema by a different parser but with the same context
                XsdSchemaParser parser(m_context, m_parserContext, reply.data());
                parser.setDocumentURI(url);
                parser.setTargetNamespace(importNamespace);
                parser.setIncludedSchemas(m_includedSchemas);
                parser.setImportedSchemas(m_importedSchemas);
                parser.setRedefinedSchemas(m_redefinedSchemas);
                if (!parser.parse(XsdSchemaParser::ImportParser)) {
                    return;
                } else {
                    // add indirectly loaded schemas to the list of already loaded ones
                    addIncludedSchemas(parser.m_includedSchemas);
                    addImportedSchemas(parser.m_importedSchemas);
                    addRedefinedSchemas(parser.m_redefinedSchemas);
                }
            }
        }
    } else {
        // check whether it is a known namespace we have a builtin schema for
        if (!importNamespace.isEmpty()) {
            if (!m_importedSchemas.contains(importNamespace)) {
                m_importedSchemas.insert(importNamespace);

                QFile file(QString::fromLatin1(":") + importNamespace);
                if (file.open(QIODevice::ReadOnly)) {
                    XsdSchemaParser parser(m_context, m_parserContext, &file);
                    parser.setDocumentURI(importNamespace);
                    parser.setTargetNamespace(importNamespace);
                    parser.setIncludedSchemas(m_includedSchemas);
                    parser.setImportedSchemas(m_importedSchemas);
                    parser.setRedefinedSchemas(m_redefinedSchemas);
                    if (!parser.parse(XsdSchemaParser::ImportParser)) {
                        return;
                    } else {
                        // add indirectly loaded schemas to the list of already loaded ones
                        addIncludedSchemas(parser.m_includedSchemas);
                        addImportedSchemas(parser.m_importedSchemas);
                        addRedefinedSchemas(parser.m_redefinedSchemas);
                    }
                }
            }
        } else {
            // we don't import anything... that is valid according to the schema
        }
    }

    validateIdAttribute("import");

    TagValidationHandler tagValidator(XsdTagScope::Import, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                m_schema->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseRedefine()
{
    Q_ASSERT(isStartElement() && XsdSchemaToken::toToken(name()) == XsdSchemaToken::Redefine &&
                                 XsdSchemaToken::toToken(namespaceUri()) == XsdSchemaToken::XML_NS_SCHEMA_URI);

    validateElement(XsdTagScope::Redefine);

    // parse attributes
    validateIdAttribute("redefine");

    const QString schemaLocation = readAttribute(QString::fromLatin1("schemaLocation"));

    TagValidationHandler tagValidator(XsdTagScope::Redefine, this, m_namePool);

    XsdSimpleType::List redefinedSimpleTypes;
    XsdComplexType::List redefinedComplexTypes;
    XsdModelGroup::List redefinedGroups;
    XsdAttributeGroup::List redefinedAttributeGroups;

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                m_schema->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                const XsdSimpleType::Ptr type = parseGlobalSimpleType();
                redefinedSimpleTypes.append(type);

                const QXmlName baseTypeName = m_parserContext->resolver()->baseTypeNameOfType(type);
                if (baseTypeName != type->name(m_namePool)) {
                    error(QString::fromLatin1("redefined simple type %1 must have itself as base type").arg(formatType(m_namePool, type)));
                    return;
                }
            } else if (isSchemaTag(XsdSchemaToken::ComplexType, token, namespaceToken)) {
                const XsdComplexType::Ptr type = parseGlobalComplexType();
                redefinedComplexTypes.append(type);

                // @see http://www.w3.org/TR/xmlschema11-1/#src-redefine

                // 5
                const QXmlName baseTypeName = m_parserContext->resolver()->baseTypeNameOfType(type);
                if (baseTypeName != type->name(m_namePool)) {
                    error(QString::fromLatin1("redefined complex type %1 must have itself as base type").arg(formatType(m_namePool, type)));
                    return;
                }
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdModelGroup::Ptr group = parseNamedGroup();
                redefinedGroups.append(group);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeGroup::Ptr group = parseNamedAttributeGroup();
                redefinedAttributeGroups.append(group);

            } else {
                parseUnknown();
            }
        }
    }

    bool locationMustResolve = false;
    if (!redefinedSimpleTypes.isEmpty() || !redefinedComplexTypes.isEmpty() ||
        !redefinedGroups.isEmpty() || !redefinedAttributeGroups.isEmpty()) {
        locationMustResolve = true;
    }

    QUrl url(schemaLocation);
    if (url.isRelative()) {
        Q_ASSERT(m_documentURI.isValid());

        url = m_documentURI.resolved(url);
    }

    // we parse the schema given in the redefine tag into its own context
    const XsdSchemaParserContext::Ptr redefinedContext(new XsdSchemaParserContext(m_namePool, m_context));

    if (m_redefinedSchemas.contains(url)) {
        // we have redefined that file already, according to the schema spec we are
        // allowed to silently skip it.
    } else {
        m_redefinedSchemas.insert(url);
        QNetworkReply *reply = AccelTreeResourceLoader::load(url, m_context->networkAccessManager(),
                                                             m_context,
                                                             (locationMustResolve ? AccelTreeResourceLoader::FailOnError : AccelTreeResourceLoader::ContinueOnError));
        if (reply) {
            // parse the included schema by a different parser but with the same context
            XsdSchemaParser parser(m_context, redefinedContext, reply);
            parser.setDocumentURI(url);
            parser.setTargetNamespaceExtended(m_targetNamespace);
            parser.setIncludedSchemas(m_includedSchemas);
            parser.setImportedSchemas(m_importedSchemas);
            parser.setRedefinedSchemas(m_redefinedSchemas);
            if (!parser.parse(XsdSchemaParser::RedefineParser)) {
                return;
            } else {
                // add indirectly loaded schemas to the list of already loaded ones
                addIncludedSchemas(parser.m_includedSchemas);
                addImportedSchemas(parser.m_importedSchemas);
                addRedefinedSchemas(parser.m_redefinedSchemas);
            }

            delete reply;
        }
    }

    XsdSimpleType::List contextSimpleTypes = redefinedContext->schema()->simpleTypes();
    XsdComplexType::List contextComplexTypes = redefinedContext->schema()->complexTypes();
    XsdModelGroup::List contextGroups = redefinedContext->schema()->elementGroups();
    XsdAttributeGroup::List contextAttributeGroups = redefinedContext->schema()->attributeGroups();

    // now we do the actual redefinition:

    // iterate over all redefined simple types
    for (int i = 0; i < redefinedSimpleTypes.count(); ++i) {
        XsdSimpleType::Ptr redefinedType = redefinedSimpleTypes.at(i);

        //TODONEXT: validation

        // search the definition they override in the context types
        bool found = false;
        for (int j = 0; j < contextSimpleTypes.count(); ++j) {
            XsdSimpleType::Ptr contextType = contextSimpleTypes.at(j);

            if (redefinedType->name(m_namePool) == contextType->name(m_namePool)) { // we found the right type
                found = true;

                // 1) set name of context type to empty name
                contextType->setName(m_parserContext->createAnonymousName(QString()));

                // 2) set the context type as base type for the redefined type
                redefinedType->setWxsSuperType(contextType);

                // 3) remove the base type resolving job from the resolver as
                //    we have set the base type here explicitly
                m_parserContext->resolver()->removeSimpleRestrictionBase(redefinedType);

                // 4) add the redefined type to the schema
                addType(redefinedType);

                // 5) add the context type as anonymous type, so the resolver
                //    can resolve it further.
                addAnonymousType(contextType);

                // 6) remove the context type from the list
                contextSimpleTypes.removeAt(j);

                break;
            }
        }

        if (!found) {
            error(QString::fromLatin1("no matching type found to redefine simple type %1").arg(formatType(m_namePool, redefinedType)));
            return;
        }
    }

    // add all remaining context simple types to the schema
    for (int i = 0; i < contextSimpleTypes.count(); ++i) {
        addType(contextSimpleTypes.at(i));
    }

    // iterate over all redefined complex types
    for (int i = 0; i < redefinedComplexTypes.count(); ++i) {
        XsdComplexType::Ptr redefinedType = redefinedComplexTypes.at(i);

        //TODONEXT: validation

        // search the definition they override in the context types
        bool found = false;
        for (int j = 0; j < contextComplexTypes.count(); ++j) {
            XsdComplexType::Ptr contextType = contextComplexTypes.at(j);

            if (redefinedType->name(m_namePool) == contextType->name(m_namePool)) { // we found the right type
                found = true;

                // 1) set name of context type to empty name
                contextType->setName(m_parserContext->createAnonymousName(QString()));

                // 2) set the context type as base type for the redefined type
                redefinedType->setWxsSuperType(contextType);

                // 3) remove the base type resolving job from the resolver as
                //    we have set the base type here explicitly
                m_parserContext->resolver()->removeComplexBaseType(redefinedType);

                // 4) add the redefined type to the schema
                addType(redefinedType);

                // 5) add the context type as anonymous type, so the resolver
                //    can resolve its attribute uses etc.
                addAnonymousType(contextType);

                // 6) remove the context type from the list
                contextComplexTypes.removeAt(j);

                break;
            }
        }

        if (!found) {
            error(QString::fromLatin1("no matching type found to redefine complex type %1").arg(formatType(m_namePool, redefinedType)));
            return;
        }
    }

    // iterate over all redefined element groups
    for (int i = 0; i < redefinedGroups.count(); ++i) {
        const XsdModelGroup::Ptr group(redefinedGroups.at(i));

        // @see http://www.w3.org/TR/xmlschema11-1/#src-redefine

        // 6
        const XsdParticle::List particles = collectGroupRef(group);
        XsdParticle::Ptr referencedParticle;
        int sameNameCounter = 0;
        for (int i = 0; i < particles.count(); ++i) {
            const XsdReference::Ptr ref(particles.at(i)->term());
            if (ref->referenceName() == group->name(m_namePool)) {
                referencedParticle = particles.at(i);

                if (referencedParticle->minimumOccurs() != 1 || referencedParticle->maximumOccurs() != 1 || referencedParticle->maximumOccursUnbounded()) { // 6.1.2
                    error(QString::fromLatin1("redefined group %1 can not contain reference to itself with minOccurs or maxOccurs != 1").arg(formatKeyword(group->displayName(m_namePool))));
                    return;
                }
                sameNameCounter++;
            }
        }

        // 6.1.1
        if (sameNameCounter > 1) {
            error(QString::fromLatin1("redefined group %1 can not contain multiple references to itself").arg(formatKeyword(group->displayName(m_namePool))));
            return;
        }

        // search the group definition in the included schema (S2)
        XsdModelGroup::Ptr contextGroup;
        for (int j = 0; j < contextGroups.count(); ++j) {
            if (group->name(m_namePool) == contextGroups.at(j)->name(m_namePool)) {
                contextGroup = contextGroups.at(j);
                break;
            }
        }

        if (!contextGroup) { // 6.2.1
            error(QString::fromLatin1("redefined group %1 has no occurrence in included schema").arg(formatKeyword(group->displayName(m_namePool))));
            return;
        }

        if (sameNameCounter == 1) {
            // there was a self reference in the redefined group, so use the
            // group from the included schema

            // set a anonymous name to the group of the included schema
            contextGroup->setName(m_parserContext->createAnonymousName(m_namePool->stringForNamespace(contextGroup->name(m_namePool).namespaceURI())));

            // replace the self-reference with the group from the included schema
            referencedParticle->setTerm(contextGroup);

            addElementGroup(group);

            addElementGroup(contextGroup);
            contextGroups.removeAll(contextGroup);
        } else {
            // there was no self reference in the redefined group

            // just add the redefined group...
            addElementGroup(group);

            // we have to add them, otherwise it is not resolved and we can't validate it later
            contextGroup->setName(m_parserContext->createAnonymousName(m_namePool->stringForNamespace(contextGroup->name(m_namePool).namespaceURI())));
            addElementGroup(contextGroup);

            m_schemaResolver->addRedefinedGroups(group, contextGroup);

            // ...and forget about the group from the included schema
            contextGroups.removeAll(contextGroup);
        }
    }

    // iterate over all redefined attribute groups
    for (int i = 0; i < redefinedAttributeGroups.count(); ++i) {
        const XsdAttributeGroup::Ptr group(redefinedAttributeGroups.at(i));

        // @see http://www.w3.org/TR/xmlschema11-1/#src-redefine

        // 7

        // 7.1
        int sameNameCounter = 0;
        for (int j = 0; j < group->attributeUses().count(); ++j) {
            const XsdAttributeUse::Ptr attributeUse(group->attributeUses().at(j));
            if (attributeUse->isReference()) {
                const XsdAttributeReference::Ptr reference(attributeUse);
                if (reference->type() == XsdAttributeReference::AttributeGroup) {
                    if (group->name(m_namePool) == reference->referenceName())
                        sameNameCounter++;
                }
            }
        }
        if (sameNameCounter > 1) {
            error(QString::fromLatin1("redefined attribute group %1 can not contain multiple references to itself").arg(formatKeyword(group->displayName(m_namePool))));
            return;
        }

        // search the attribute group definition in the included schema (S2)
        XsdAttributeGroup::Ptr baseGroup;
        for (int j = 0; j < contextAttributeGroups.count(); ++j) {
            const XsdAttributeGroup::Ptr contextGroup(contextAttributeGroups.at(j));
            if (group->name(m_namePool) == contextGroup->name(m_namePool)) {
                baseGroup = contextGroup;
                break;
            }
        }

        if (!baseGroup) { // 7.2.1
            error(QString::fromLatin1("redefined attribute group %1 has no occurrence in included schema").arg(formatKeyword(group->displayName(m_namePool))));
            return;
        }

        if (sameNameCounter == 1) {

            // first set an anonymous name to the attribute group from the included
            // schema
            baseGroup->setName(m_parserContext->createAnonymousName(m_namePool->stringForNamespace(baseGroup->name(m_namePool).namespaceURI())));

            // iterate over the attribute uses of the redefined attribute group
            // and replace the self-reference with the attribute group from the
            // included schema
            for (int j = 0; j < group->attributeUses().count(); ++j) {
                const XsdAttributeUse::Ptr attributeUse(group->attributeUses().at(j));
                if (attributeUse->isReference()) {
                    const XsdAttributeReference::Ptr reference(attributeUse);
                    if (reference->type() == XsdAttributeReference::AttributeGroup) {
                        if (group->name(m_namePool) == reference->referenceName()) {
                            reference->setReferenceName(baseGroup->name(m_namePool));
                            break;
                        }
                    }
                }
            }

            // add both groups to the target schema
            addAttributeGroup(baseGroup);
            addAttributeGroup(group);

            contextAttributeGroups.removeAll(baseGroup);
        }

        if (sameNameCounter == 0) { // 7.2

            // we have to add them, otherwise it is not resolved and we can't validate it later
            baseGroup->setName(m_parserContext->createAnonymousName(m_namePool->stringForNamespace(baseGroup->name(m_namePool).namespaceURI())));
            addAttributeGroup(baseGroup);

            m_schemaResolver->addRedefinedAttributeGroups(group, baseGroup);

            // just add the redefined attribute group to the target schema...
            addAttributeGroup(group);

            // ... and forget about the one from the included schema
            contextAttributeGroups.removeAll(baseGroup);
        }
    }

    // add all remaining context complex types to the schema
    for (int i = 0; i < contextComplexTypes.count(); ++i) {
        addType(contextComplexTypes.at(i));
    }

    // add all remaining context element groups to the schema
    for (int i = 0; i < contextGroups.count(); ++i) {
        addElementGroup(contextGroups.at(i));
    }

    // add all remaining context attribute groups to the schema
    for (int i = 0; i < contextAttributeGroups.count(); ++i) {
        addAttributeGroup(contextAttributeGroups.at(i));
    }

    // copy all elements, attributes and notations
    const XsdElement::List contextElements = redefinedContext->schema()->elements();
    for (int i = 0; i < contextElements.count(); ++i) {
        addElement(contextElements.at(i));
    }

    const XsdAttribute::List contextAttributes = redefinedContext->schema()->attributes();
    for (int i = 0; i < contextAttributes.count(); ++i) {
        addAttribute(contextAttributes.at(i));
    }

    const XsdNotation::List contextNotations = redefinedContext->schema()->notations();
    for (int i = 0; i < contextNotations.count(); ++i) {
        addNotation(contextNotations.at(i));
    }

    // push all data to resolve from the context resolver to our resolver
    redefinedContext->resolver()->copyDataTo(m_parserContext->resolver());

    tagValidator.finalize();
}

XsdAnnotation::Ptr XsdSchemaParser::parseAnnotation()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Annotation, this);

    validateElement(XsdTagScope::Annotation);

    // parse attributes
    validateIdAttribute("annotation");

    TagValidationHandler tagValidator(XsdTagScope::Annotation, this, m_namePool);

    const XsdAnnotation::Ptr annotation(new XsdAnnotation());

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Appinfo, token, namespaceToken)) {
                const XsdApplicationInformation::Ptr info = parseAppInfo();
                annotation->addApplicationInformation(info);
            } else if (isSchemaTag(XsdSchemaToken::Documentation, token, namespaceToken)) {
                const XsdDocumentation::Ptr documentation = parseDocumentation();
                annotation->addDocumentation(documentation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return annotation;
}

XsdApplicationInformation::Ptr XsdSchemaParser::parseAppInfo()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Appinfo, this);

    validateElement(XsdTagScope::AppInfo);

    const XsdApplicationInformation::Ptr info(new XsdApplicationInformation());

    // parse attributes
    if (hasAttribute(QString::fromLatin1("source"))) {
        const QString value = readAttribute(QString::fromLatin1("source"));

        if (!isValidUri(value)) {
            attributeContentError("source", "appinfo", value, BuiltinTypes::xsAnyURI);
            return info;
        }

        if (!value.isEmpty()) {
            const AnyURI::Ptr source = AnyURI::fromLexical(value);
            info->setSource(source);
        }
    }

    while (!atEnd()) { //EVAL: can be anything... what to do?
        readNext();

        if (isEndElement())
            break;

        if (isStartElement())
            parseUnknownDocumentation();
    }

    return info;
}

XsdDocumentation::Ptr XsdSchemaParser::parseDocumentation()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Documentation, this);

    validateElement(XsdTagScope::Documentation);

    const XsdDocumentation::Ptr documentation(new XsdDocumentation());

    // parse attributes
    if (hasAttribute(QString::fromLatin1("source"))) {
        const QString value = readAttribute(QString::fromLatin1("source"));

        if (!isValidUri(value)) {
            attributeContentError("source", "documentation", value, BuiltinTypes::xsAnyURI);
            return documentation;
        }

        if (!value.isEmpty()) {
            const AnyURI::Ptr source = AnyURI::fromLexical(value);
            documentation->setSource(source);
        }
    }

    if (hasAttribute(CommonNamespaces::XML, QString::fromLatin1("lang"))) {
        const QString value = readAttribute(QString::fromLatin1("lang"), CommonNamespaces::XML);

        QRegExp exp(QString::fromLatin1("[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*"));
        if (!exp.exactMatch(value)) {
            attributeContentError("xml:lang", "documentation", value);
            return documentation;
        }
    }

    while (!atEnd()) { //EVAL: can by any... what to do?
        readNext();

        if (isEndElement())
            break;

        if (isStartElement())
            parseUnknownDocumentation();
    }

    return documentation;
}

void XsdSchemaParser::parseDefaultOpenContent()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::DefaultOpenContent, this);

    validateElement(XsdTagScope::DefaultOpenContent);

    m_defaultOpenContent = XsdComplexType::OpenContent::Ptr(new XsdComplexType::OpenContent());

    if (hasAttribute(QString::fromLatin1("appliesToEmpty"))) {
        const QString value = readAttribute(QString::fromLatin1("appliesToEmpty"));
        const Boolean::Ptr appliesToEmpty = Boolean::fromLexical(value);
        if (appliesToEmpty->hasError()) {
            attributeContentError("appliesToEmpty", "defaultOpenContent", value, BuiltinTypes::xsBoolean);
            return;
        }

        m_defaultOpenContentAppliesToEmpty = appliesToEmpty->as<Boolean>()->value();
    } else {
        m_defaultOpenContentAppliesToEmpty = false;
    }

    if (hasAttribute(QString::fromLatin1("mode"))) {
        const QString mode = readAttribute(QString::fromLatin1("mode"));

        if (mode == QString::fromLatin1("interleave")) {
            m_defaultOpenContent->setMode(XsdComplexType::OpenContent::Interleave);
        } else if (mode == QString::fromLatin1("suffix")) {
            m_defaultOpenContent->setMode(XsdComplexType::OpenContent::Suffix);
        } else {
            attributeContentError("mode", "defaultOpenContent", mode);
            return;
        }
    } else {
        m_defaultOpenContent->setMode(XsdComplexType::OpenContent::Interleave);
    }

    validateIdAttribute("defaultOpenContent");

    TagValidationHandler tagValidator(XsdTagScope::DefaultOpenContent, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                m_defaultOpenContent->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle;
                const XsdWildcard::Ptr wildcard = parseAny(particle);
                m_defaultOpenContent->setWildcard(wildcard);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

XsdSimpleType::Ptr XsdSchemaParser::parseGlobalSimpleType()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::SimpleType, this);

    validateElement(XsdTagScope::GlobalSimpleType);

    const XsdSimpleType::Ptr simpleType(new XsdSimpleType());
    simpleType->setCategory(XsdSimpleType::SimpleTypeAtomic); // just to make sure it's not invalid

    // parse attributes
    const SchemaType::DerivationConstraints allowedConstraints(SchemaType::ExtensionConstraint | SchemaType::RestrictionConstraint | SchemaType::ListConstraint | SchemaType::UnionConstraint);
    simpleType->setDerivationConstraints(readDerivationConstraintAttribute(allowedConstraints, "simpleType"));

    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("simpleType"));
    simpleType->setName(objectName);

    validateIdAttribute("simpleType");

    TagValidationHandler tagValidator(XsdTagScope::GlobalSimpleType, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                simpleType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Restriction, token, namespaceToken)) {
                parseSimpleRestriction(simpleType);
            } else if (isSchemaTag(XsdSchemaToken::List, token, namespaceToken)) {
                parseList(simpleType);
            } else if (isSchemaTag(XsdSchemaToken::Union, token, namespaceToken)) {
                parseUnion(simpleType);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return simpleType;
}

XsdSimpleType::Ptr XsdSchemaParser::parseLocalSimpleType()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::SimpleType, this);

    validateElement(XsdTagScope::LocalSimpleType);

    const XsdSimpleType::Ptr simpleType(new XsdSimpleType());
    simpleType->setCategory(XsdSimpleType::SimpleTypeAtomic); // just to make sure it's not invalid
    simpleType->setName(m_parserContext->createAnonymousName(m_targetNamespace));

    validateIdAttribute("simpleType");

    TagValidationHandler tagValidator(XsdTagScope::LocalSimpleType, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                simpleType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Restriction, token, namespaceToken)) {
                parseSimpleRestriction(simpleType);
            } else if (isSchemaTag(XsdSchemaToken::List, token, namespaceToken)) {
                parseList(simpleType);
            } else if (isSchemaTag(XsdSchemaToken::Union, token, namespaceToken)) {
                parseUnion(simpleType);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return simpleType;
}

void XsdSchemaParser::parseSimpleRestriction(const XsdSimpleType::Ptr &ptr)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Restriction, this);

    validateElement(XsdTagScope::SimpleRestriction);

    ptr->setDerivationMethod(XsdSimpleType::DerivationRestriction);

    // The base attribute and simpleType member are mutually exclusive,
    // so we keep track of that
    bool hasBaseAttribute = false;
    bool hasBaseTypeSpecified = false;

    QXmlName baseName;
    if (hasAttribute(QString::fromLatin1("base"))) {
        const QString base = readQNameAttribute(QString::fromLatin1("base"), "restriction");
        convertName(base, NamespaceSupport::ElementName, baseName); // translate qualified name into QXmlName
        m_schemaResolver->addSimpleRestrictionBase(ptr, baseName, currentSourceLocation()); // add to resolver

        hasBaseAttribute = true;
        hasBaseTypeSpecified = true;
    }
    validateIdAttribute("restriction");

    XsdFacet::Hash facets;
    QList<XsdFacet::Ptr> patternFacets;
    QList<XsdFacet::Ptr> enumerationFacets;
    QList<XsdFacet::Ptr> assertionFacets;

    TagValidationHandler tagValidator(XsdTagScope::SimpleRestriction, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                ptr->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasBaseAttribute) {
                    error(QtXmlPatterns::tr("%1 element is not allowed inside %2 element if %3 attribute is present.")
                                           .arg(formatElement("simpleType"))
                                           .arg(formatElement("restriction"))
                                           .arg(formatAttribute("base")));
                    return;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(ptr);
                ptr->setWxsSuperType(type);
                ptr->setCategory(type->category());
                hasBaseTypeSpecified = true;

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else if (isSchemaTag(XsdSchemaToken::MinExclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinExclusiveFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::MinInclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinInclusiveFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::MaxExclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxExclusiveFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::MaxInclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxInclusiveFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::TotalDigits, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseTotalDigitsFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::FractionDigits, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseFractionDigitsFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::Length, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseLengthFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::MinLength, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinLengthFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::MaxLength, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxLengthFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::Enumeration, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseEnumerationFacet();
                enumerationFacets.append(facet);
            } else if (isSchemaTag(XsdSchemaToken::WhiteSpace, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseWhiteSpaceFacet();
                addFacet(facet, facets, ptr);
            } else if (isSchemaTag(XsdSchemaToken::Pattern, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parsePatternFacet();
                patternFacets.append(facet);
            } else if (isSchemaTag(XsdSchemaToken::Assertion, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseAssertionFacet();
                assertionFacets.append(facet);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasBaseTypeSpecified) {
        error(QtXmlPatterns::tr("%1 element has neither %2 attribute nor %3 child element.")
                               .arg(formatElement("restriction"))
                               .arg(formatAttribute("base"))
                               .arg(formatElement("simpleType")));
        return;
    }

    // merge all pattern facets into one multi value facet
    if (!patternFacets.isEmpty()) {
        const XsdFacet::Ptr patternFacet(new XsdFacet());
        patternFacet->setType(XsdFacet::Pattern);

        AtomicValue::List multiValue;
        for (int i = 0; i < patternFacets.count(); ++i)
            multiValue << patternFacets.at(i)->multiValue();

        patternFacet->setMultiValue(multiValue);
        addFacet(patternFacet, facets, ptr);
    }

    // merge all enumeration facets into one multi value facet
    if (!enumerationFacets.isEmpty()) {
        const XsdFacet::Ptr enumerationFacet(new XsdFacet());
        enumerationFacet->setType(XsdFacet::Enumeration);

        AtomicValue::List multiValue;
        for (int i = 0; i < enumerationFacets.count(); ++i)
            multiValue << enumerationFacets.at(i)->multiValue();

        enumerationFacet->setMultiValue(multiValue);
        addFacet(enumerationFacet, facets, ptr);
    }

    // merge all assertion facets into one facet
    if (!assertionFacets.isEmpty()) {
        const XsdFacet::Ptr assertionFacet(new XsdFacet());
        assertionFacet->setType(XsdFacet::Assertion);

        XsdAssertion::List assertions;
        for (int i = 0; i < assertionFacets.count(); ++i)
            assertions << assertionFacets.at(i)->assertions();

        assertionFacet->setAssertions(assertions);
        addFacet(assertionFacet, facets, ptr);
    }

    ptr->setFacets(facets);

    tagValidator.finalize();
}

void XsdSchemaParser::parseList(const XsdSimpleType::Ptr &ptr)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::List, this);

    validateElement(XsdTagScope::List);

    ptr->setCategory(XsdSimpleType::SimpleTypeList);
    ptr->setDerivationMethod(XsdSimpleType::DerivationList);
    ptr->setWxsSuperType(BuiltinTypes::xsAnySimpleType);

    // The itemType attribute and simpleType member are mutually exclusive,
    // so we keep track of that
    bool hasItemTypeAttribute = false;
    bool hasItemTypeSpecified = false;

    if (hasAttribute(QString::fromLatin1("itemType"))) {
        const QString itemType = readQNameAttribute(QString::fromLatin1("itemType"), "list");
        QXmlName typeName;
        convertName(itemType, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
        m_schemaResolver->addSimpleListType(ptr, typeName, currentSourceLocation()); // add to resolver

        hasItemTypeAttribute = true;
        hasItemTypeSpecified = true;
    }

    validateIdAttribute("list");

    TagValidationHandler tagValidator(XsdTagScope::List, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                ptr->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasItemTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element is not allowed inside %2 element if %3 attribute is present.")
                                           .arg(formatElement("simpleType"))
                                           .arg(formatElement("list"))
                                           .arg(formatAttribute("itemType")));
                    return;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(ptr);
                ptr->setItemType(type);

                hasItemTypeSpecified = true;

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasItemTypeSpecified) {
        error(QtXmlPatterns::tr("%1 element has neither %2 attribute nor %3 child element.")
                               .arg(formatElement("list"))
                               .arg(formatAttribute("itemType"))
                               .arg(formatElement("simpleType")));
        return;
    }

    tagValidator.finalize();

    // add the default white space facet that every simple type with list derivation has
    const XsdFacet::Ptr defaultFacet(new XsdFacet());
    defaultFacet->setType(XsdFacet::WhiteSpace);
    defaultFacet->setFixed(true);
    defaultFacet->setValue(DerivedString<TypeString>::fromLexical(m_namePool, XsdSchemaToken::toString(XsdSchemaToken::Collapse)));
    XsdFacet::Hash facets;
    facets.insert(defaultFacet->type(), defaultFacet);
    ptr->setFacets(facets);
}

void XsdSchemaParser::parseUnion(const XsdSimpleType::Ptr &ptr)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Union, this);

    validateElement(XsdTagScope::Union);

    ptr->setCategory(XsdSimpleType::SimpleTypeUnion);
    ptr->setDerivationMethod(XsdSimpleType::DerivationUnion);
    ptr->setWxsSuperType(BuiltinTypes::xsAnySimpleType);

    // The memberTypes attribute is not allowed to be empty,
    // so we keep track of that
    bool hasMemberTypesSpecified = false;

    if (hasAttribute(QString::fromLatin1("memberTypes"))) {
        const QStringList memberTypes = readAttribute(QString::fromLatin1("memberTypes")).split(QLatin1Char(' '), QString::SkipEmptyParts);
        QList<QXmlName> typeNames;

        for (int i = 0; i < memberTypes.count(); ++i) {
            QXmlName typeName;
            convertName(memberTypes.at(i), NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
            typeNames.append(typeName);
        }

        if (!typeNames.isEmpty()) {
            m_schemaResolver->addSimpleUnionTypes(ptr, typeNames, currentSourceLocation()); // add to resolver
            hasMemberTypesSpecified = true;
        }
    }

    validateIdAttribute("union");

    AnySimpleType::List memberTypes;

    TagValidationHandler tagValidator(XsdTagScope::Union, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                ptr->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(ptr);
                memberTypes.append(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else {
                parseUnknown();
            }
        }
    }

    if (!memberTypes.isEmpty()) {
        ptr->setMemberTypes(memberTypes);
        hasMemberTypesSpecified = true;
    }

    if (!hasMemberTypesSpecified) {
        error(QtXmlPatterns::tr("%1 element has neither %2 attribute nor %3 child element.")
                               .arg(formatElement("union"))
                               .arg(formatAttribute("memberTypes"))
                               .arg(formatElement("simpleType")));
        return;
    }

    tagValidator.finalize();
}

XsdFacet::Ptr XsdSchemaParser::parseMinExclusiveFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MinExclusive, this);

    validateElement(XsdTagScope::MinExclusiveFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MinimumExclusive);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "minExclusive", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    // as minExclusive can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "minExclusive", value, BuiltinTypes::xsAnySimpleType);
        return facet;
    } else {
        facet->setValue(string);
    }

    validateIdAttribute("minExclusive");

    TagValidationHandler tagValidator(XsdTagScope::MinExclusiveFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseMinInclusiveFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MinInclusive, this);

    validateElement(XsdTagScope::MinInclusiveFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MinimumInclusive);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "minInclusive", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    // as minInclusive can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "minInclusive", value, BuiltinTypes::xsAnySimpleType);
        return facet;
    } else {
        facet->setValue(string);
    }

    validateIdAttribute("minInclusive");

    TagValidationHandler tagValidator(XsdTagScope::MinInclusiveFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseMaxExclusiveFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MaxExclusive, this);

    validateElement(XsdTagScope::MaxExclusiveFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MaximumExclusive);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "maxExclusive", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    // as maxExclusive can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "maxExclusive", value, BuiltinTypes::xsAnySimpleType);
        return facet;
    } else {
        facet->setValue(string);
    }

    validateIdAttribute("maxExclusive");

    TagValidationHandler tagValidator(XsdTagScope::MaxExclusiveFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseMaxInclusiveFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MaxInclusive, this);

    validateElement(XsdTagScope::MaxInclusiveFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MaximumInclusive);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "maxInclusive", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    // as maxInclusive can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "maxInclusive", value, BuiltinTypes::xsAnySimpleType);
        return facet;
    } else {
        facet->setValue(string);
    }

    validateIdAttribute("maxInclusive");

    TagValidationHandler tagValidator(XsdTagScope::MaxInclusiveFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseTotalDigitsFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::TotalDigits, this);

    validateElement(XsdTagScope::TotalDigitsFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::TotalDigits);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "totalDigits", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedInteger<TypePositiveInteger>::Ptr integer = DerivedInteger<TypePositiveInteger>::fromLexical(m_namePool, value);
    if (integer->hasError()) {
        attributeContentError("value", "totalDigits", value, BuiltinTypes::xsPositiveInteger);
        return facet;
    } else {
        facet->setValue(integer);
    }

    validateIdAttribute("totalDigits");

    TagValidationHandler tagValidator(XsdTagScope::TotalDigitsFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseFractionDigitsFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::FractionDigits, this);

    validateElement(XsdTagScope::FractionDigitsFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::FractionDigits);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "fractionDigits", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
    if (integer->hasError()) {
        attributeContentError("value", "fractionDigits", value, BuiltinTypes::xsNonNegativeInteger);
        return facet;
    } else {
        facet->setValue(integer);
    }

    validateIdAttribute("fractionDigits");

    TagValidationHandler tagValidator(XsdTagScope::FractionDigitsFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseLengthFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Length, this);

    validateElement(XsdTagScope::LengthFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::Length);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "length", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
    if (integer->hasError()) {
        attributeContentError("value", "length", value, BuiltinTypes::xsNonNegativeInteger);
        return facet;
    } else {
        facet->setValue(integer);
    }

    validateIdAttribute("length");

    TagValidationHandler tagValidator(XsdTagScope::LengthFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseMinLengthFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MinLength, this);

    validateElement(XsdTagScope::MinLengthFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MinimumLength);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "minLength", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
    if (integer->hasError()) {
        attributeContentError("value", "minLength", value, BuiltinTypes::xsNonNegativeInteger);
        return facet;
    } else {
        facet->setValue(integer);
    }

    validateIdAttribute("minLength");

    TagValidationHandler tagValidator(XsdTagScope::MinLengthFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseMaxLengthFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::MaxLength, this);

    validateElement(XsdTagScope::MaxLengthFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::MaximumLength);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "maxLength", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
    if (integer->hasError()) {
        attributeContentError("value", "maxLength", value, BuiltinTypes::xsNonNegativeInteger);
        return facet;
    } else {
        facet->setValue(integer);
    }

    validateIdAttribute("maxLength");

    TagValidationHandler tagValidator(XsdTagScope::MaxLengthFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseEnumerationFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Enumeration, this);

    validateElement(XsdTagScope::EnumerationFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::Enumeration);

    // parse attributes
    facet->setFixed(false); // not defined in schema, but can't hurt

    const QString value = readAttribute(QString::fromLatin1("value"));

    // as enumeration can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "enumeration", value);
        return facet;
    } else {
        AtomicValue::List multiValue;
        multiValue << string;
        facet->setMultiValue(multiValue);
    }
    m_schemaResolver->addEnumerationFacetValue(string, m_namespaceSupport);

    validateIdAttribute("enumeration");

    TagValidationHandler tagValidator(XsdTagScope::EnumerationFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseWhiteSpaceFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::WhiteSpace, this);

    validateElement(XsdTagScope::WhiteSpaceFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::WhiteSpace);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        const Boolean::Ptr fixed = Boolean::fromLexical(value);
        if (fixed->hasError()) {
            attributeContentError("fixed", "whiteSpace", value, BuiltinTypes::xsBoolean);
            return facet;
        }

        facet->setFixed(fixed->as<Boolean>()->value());
    } else {
        facet->setFixed(false); // the default value
    }

    const QString value = readAttribute(QString::fromLatin1("value"));
    if (value != XsdSchemaToken::toString(XsdSchemaToken::Collapse) &&
        value != XsdSchemaToken::toString(XsdSchemaToken::Preserve) &&
        value != XsdSchemaToken::toString(XsdSchemaToken::Replace)) {
        attributeContentError("value", "whiteSpace", value);
        return facet;
    } else {
        DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
        if (string->hasError()) {
            attributeContentError("value", "whiteSpace", value);
            return facet;
        } else {
            facet->setValue(string);
        }
    }

    validateIdAttribute("whiteSpace");

    TagValidationHandler tagValidator(XsdTagScope::WhiteSpaceFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parsePatternFacet()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Pattern, this);

    validateElement(XsdTagScope::PatternFacet);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::Pattern);

    // parse attributes

    // as pattern can have a value of type anySimpleType, we just read
    // the string here and store it for later intepretation
    const QString value = readAttribute(QString::fromLatin1("value"));
    DerivedString<TypeString>::Ptr string = DerivedString<TypeString>::fromLexical(m_namePool, value);
    if (string->hasError()) {
        attributeContentError("value", "pattern", value);
        return facet;
    } else {
        AtomicValue::List multiValue;
        multiValue << string;
        facet->setMultiValue(multiValue);
    }

    validateIdAttribute("pattern");

    TagValidationHandler tagValidator(XsdTagScope::PatternFacet, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                facet->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return facet;
}

XsdFacet::Ptr XsdSchemaParser::parseAssertionFacet()
{
    // this is just a wrapper function around the parseAssertion() method

    const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assertion, XsdTagScope::Assertion);

    const XsdFacet::Ptr facet = XsdFacet::Ptr(new XsdFacet());
    facet->setType(XsdFacet::Assertion);
    facet->setAssertions(XsdAssertion::List() << assertion);

    return facet;
}

XsdComplexType::Ptr XsdSchemaParser::parseGlobalComplexType()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::ComplexType, this);

    validateElement(XsdTagScope::GlobalComplexType);

    bool hasTypeSpecified = false;
    bool hasComplexContent = false;

    const XsdComplexType::Ptr complexType(new XsdComplexType());

    // parse attributes
    if (hasAttribute(QString::fromLatin1("abstract"))) {
        const QString abstract = readAttribute(QString::fromLatin1("abstract"));

        const Boolean::Ptr value = Boolean::fromLexical(abstract);
        if (value->hasError()) {
            attributeContentError("abstract", "complexType", abstract, BuiltinTypes::xsBoolean);
            return complexType;
        }

        complexType->setIsAbstract(value->as<Boolean>()->value());
    } else {
        complexType->setIsAbstract(false);  // default value
    }

    complexType->setProhibitedSubstitutions(readBlockingConstraintAttribute(NamedSchemaComponent::ExtensionConstraint | NamedSchemaComponent::RestrictionConstraint, "complexType"));
    complexType->setDerivationConstraints(readDerivationConstraintAttribute(SchemaType::ExtensionConstraint | SchemaType::RestrictionConstraint, "complexType"));

    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("complexType"));
    complexType->setName(objectName);

    bool effectiveMixed = false;
    if (hasAttribute(QString::fromLatin1("mixed"))) {
        const QString mixed = readAttribute(QString::fromLatin1("mixed"));

        const Boolean::Ptr value = Boolean::fromLexical(mixed);
        if (value->hasError()) {
            attributeContentError("mixed", "complexType", mixed, BuiltinTypes::xsBoolean);
            return complexType;
        }

        effectiveMixed = value->as<Boolean>()->value();
    }

    validateIdAttribute("complexType");

    TagValidationHandler tagValidator(XsdTagScope::GlobalComplexType, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleContent, token, namespaceToken)) {
                if (effectiveMixed) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                            .arg(formatElement("complexType"))
                                            .arg(formatElement("simpleContent"))
                                            .arg(formatAttribute("mixed")));
                    return complexType;
                }

                parseSimpleContent(complexType);
                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::ComplexContent, token, namespaceToken)) {
                bool mixed;
                parseComplexContent(complexType, &mixed);
                hasTypeSpecified = true;

                effectiveMixed = (effectiveMixed || mixed);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::OpenContent, token, namespaceToken)) {
                const XsdComplexType::OpenContent::Ptr openContent = parseOpenContent();
                complexType->contentType()->setOpenContent(openContent);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::All, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalAll(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    if (!hasTypeSpecified) {
        complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
        complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
        hasComplexContent = true;
    }

    if (hasComplexContent == true) {
        resolveComplexContentType(complexType, effectiveMixed);
    }

    return complexType;
}

XsdComplexType::Ptr XsdSchemaParser::parseLocalComplexType()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::ComplexType, this);

    validateElement(XsdTagScope::LocalComplexType);

    bool hasTypeSpecified = false;
    bool hasComplexContent = true;

    const XsdComplexType::Ptr complexType(new XsdComplexType());
    complexType->setName(m_parserContext->createAnonymousName(m_targetNamespace));

    // parse attributes
    bool effectiveMixed = false;
    if (hasAttribute(QString::fromLatin1("mixed"))) {
        const QString mixed = readAttribute(QString::fromLatin1("mixed"));

        const Boolean::Ptr value = Boolean::fromLexical(mixed);
        if (value->hasError()) {
            attributeContentError("mixed", "complexType", mixed, BuiltinTypes::xsBoolean);
            return complexType;
        }

        effectiveMixed = value->as<Boolean>()->value();
    }

    validateIdAttribute("complexType");

    TagValidationHandler tagValidator(XsdTagScope::LocalComplexType, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleContent, token, namespaceToken)) {
                parseSimpleContent(complexType);
                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::ComplexContent, token, namespaceToken)) {
                bool mixed;
                parseComplexContent(complexType, &mixed);
                hasTypeSpecified = true;

                effectiveMixed = (effectiveMixed || mixed);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::OpenContent, token, namespaceToken)) {
                const XsdComplexType::OpenContent::Ptr openContent = parseOpenContent();
                complexType->contentType()->setOpenContent(openContent);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::All, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalAll(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);

                complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
                complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);
                complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
                hasComplexContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    if (!hasTypeSpecified) {
        complexType->setWxsSuperType(BuiltinTypes::xsAnyType);
        complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);
        hasComplexContent = true;
    }

    if (hasComplexContent == true) {
        resolveComplexContentType(complexType, effectiveMixed);
    }

    return complexType;
}

void XsdSchemaParser::resolveComplexContentType(const XsdComplexType::Ptr &complexType, bool effectiveMixed)
{
    // @see http://www.w3.org/TR/xmlschema11-1/#dcl.ctd.ctcc.common

    // 1
    // the effectiveMixed contains the effective mixed value

    // 2
    bool hasEmptyContent = false;
    if (!complexType->contentType()->particle()) {
        hasEmptyContent = true; // 2.1.1
    } else {
        if (complexType->contentType()->particle()->term()->isModelGroup()) {
            const XsdModelGroup::Ptr group = complexType->contentType()->particle()->term();
            if (group->compositor() == XsdModelGroup::SequenceCompositor || group->compositor() == XsdModelGroup::AllCompositor) {
                if (group->particles().isEmpty())
                    hasEmptyContent = true; // 2.1.2
            } else if (group->compositor() == XsdModelGroup::ChoiceCompositor) {
                if ((complexType->contentType()->particle()->minimumOccurs() == 0) && group->particles().isEmpty())
                    hasEmptyContent = true; // 2.1.3
            }

            if ((complexType->contentType()->particle()->maximumOccursUnbounded() == false) && (complexType->contentType()->particle()->maximumOccurs() == 0))
                hasEmptyContent = true; // 2.1.4
        }
    }

    const XsdParticle::Ptr explicitContent = (hasEmptyContent ? XsdParticle::Ptr() : complexType->contentType()->particle());

    // do all the other work (3, 4, 5 and 6) in the resolver, as they need access to the base type object
    m_schemaResolver->addComplexContentType(complexType, explicitContent, effectiveMixed);
}

void XsdSchemaParser::parseSimpleContent(const XsdComplexType::Ptr &complexType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::SimpleContent, this);

    validateElement(XsdTagScope::SimpleContent);

    complexType->contentType()->setVariety(XsdComplexType::ContentType::Simple);

    // parse attributes
    validateIdAttribute("simpleContent");

    TagValidationHandler tagValidator(XsdTagScope::SimpleContent, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Restriction, token, namespaceToken)) {
                parseSimpleContentRestriction(complexType);
            } else if (isSchemaTag(XsdSchemaToken::Extension, token, namespaceToken)) {
                parseSimpleContentExtension(complexType);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseSimpleContentRestriction(const XsdComplexType::Ptr &complexType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Restriction, this);

    validateElement(XsdTagScope::SimpleContentRestriction);

    complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);

    // parse attributes
    const QString baseType = readQNameAttribute(QString::fromLatin1("base"), "restriction");
    QXmlName typeName;
    convertName(baseType, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName

    validateIdAttribute("restriction");

    XsdFacet::Hash facets;
    QList<XsdFacet::Ptr> patternFacets;
    QList<XsdFacet::Ptr> enumerationFacets;
    QList<XsdFacet::Ptr> assertionFacets;

    TagValidationHandler tagValidator(XsdTagScope::SimpleContentRestriction, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(complexType); //TODO: investigate what the schema spec really wants here?!?
                complexType->contentType()->setSimpleType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else if (isSchemaTag(XsdSchemaToken::MinExclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinExclusiveFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::MinInclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinInclusiveFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::MaxExclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxExclusiveFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::MaxInclusive, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxInclusiveFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::TotalDigits, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseTotalDigitsFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::FractionDigits, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseFractionDigitsFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::Length, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseLengthFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::MinLength, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMinLengthFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::MaxLength, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseMaxLengthFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::Enumeration, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseEnumerationFacet();
                enumerationFacets.append(facet);
            } else if (isSchemaTag(XsdSchemaToken::WhiteSpace, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseWhiteSpaceFacet();
                addFacet(facet, facets, complexType);
            } else if (isSchemaTag(XsdSchemaToken::Pattern, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parsePatternFacet();
                patternFacets.append(facet);
            } else if (isSchemaTag(XsdSchemaToken::Assertion, token, namespaceToken)) {
                const XsdFacet::Ptr facet = parseAssertionFacet();
                assertionFacets.append(facet);
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    // merge all pattern facets into one multi value facet
    if (!patternFacets.isEmpty()) {
        const XsdFacet::Ptr patternFacet(new XsdFacet());
        patternFacet->setType(XsdFacet::Pattern);

        AtomicValue::List multiValue;
        for (int i = 0; i < patternFacets.count(); ++i)
            multiValue << patternFacets.at(i)->multiValue();

        patternFacet->setMultiValue(multiValue);
        addFacet(patternFacet, facets, complexType);
    }

    // merge all enumeration facets into one multi value facet
    if (!enumerationFacets.isEmpty()) {
        const XsdFacet::Ptr enumerationFacet(new XsdFacet());
        enumerationFacet->setType(XsdFacet::Enumeration);

        AtomicValue::List multiValue;
        for (int i = 0; i < enumerationFacets.count(); ++i)
            multiValue << enumerationFacets.at(i)->multiValue();

        enumerationFacet->setMultiValue(multiValue);
        addFacet(enumerationFacet, facets, complexType);
    }

    // merge all assertion facets into one facet
    if (!assertionFacets.isEmpty()) {
        const XsdFacet::Ptr assertionFacet(new XsdFacet());
        assertionFacet->setType(XsdFacet::Assertion);

        XsdAssertion::List assertions;
        for (int i = 0; i < assertionFacets.count(); ++i)
            assertions << assertionFacets.at(i)->assertions();

        assertionFacet->setAssertions(assertions);
        addFacet(assertionFacet, facets, complexType);
    }

    m_schemaResolver->addComplexBaseType(complexType, typeName, currentSourceLocation(), facets); // add to resolver
}

void XsdSchemaParser::parseSimpleContentExtension(const XsdComplexType::Ptr &complexType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Extension, this);

    validateElement(XsdTagScope::SimpleContentExtension);

    complexType->setDerivationMethod(XsdComplexType::DerivationExtension);

    // parse attributes
    const QString baseType = readQNameAttribute(QString::fromLatin1("base"), "extension");
    QXmlName typeName;
    convertName(baseType, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
    m_schemaResolver->addComplexBaseType(complexType, typeName, currentSourceLocation()); // add to resolver

    validateIdAttribute("extension");

    TagValidationHandler tagValidator(XsdTagScope::SimpleContentExtension, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseComplexContent(const XsdComplexType::Ptr &complexType, bool *mixed)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::ComplexContent, this);

    validateElement(XsdTagScope::ComplexContent);

    complexType->contentType()->setVariety(XsdComplexType::ContentType::ElementOnly);

    // parse attributes
    if (hasAttribute(QString::fromLatin1("mixed"))) {
        const QString mixedStr = readAttribute(QString::fromLatin1("mixed"));

        const Boolean::Ptr value = Boolean::fromLexical(mixedStr);
        if (value->hasError()) {
            attributeContentError("mixed", "complexType", mixedStr, BuiltinTypes::xsBoolean);
            return;
        }

        *mixed = value->as<Boolean>()->value();
    } else {
        *mixed = false;
    }

    validateIdAttribute("complexContent");

    TagValidationHandler tagValidator(XsdTagScope::ComplexContent, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Restriction, token, namespaceToken)) {
                parseComplexContentRestriction(complexType);
            } else if (isSchemaTag(XsdSchemaToken::Extension, token, namespaceToken)) {
                parseComplexContentExtension(complexType);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseComplexContentRestriction(const XsdComplexType::Ptr &complexType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Restriction, this);

    validateElement(XsdTagScope::ComplexContentRestriction);

    complexType->setDerivationMethod(XsdComplexType::DerivationRestriction);

    // parse attributes
    const QString baseType = readQNameAttribute(QString::fromLatin1("base"), "restriction");
    QXmlName typeName;
    convertName(baseType, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
    m_schemaResolver->addComplexBaseType(complexType, typeName, currentSourceLocation()); // add to resolver

    validateIdAttribute("restriction");

    TagValidationHandler tagValidator(XsdTagScope::ComplexContentRestriction, this, m_namePool);

    bool hasContent = false;
    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::OpenContent, token, namespaceToken)) {
                const XsdComplexType::OpenContent::Ptr openContent = parseOpenContent();
                complexType->contentType()->setOpenContent(openContent);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::All, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalAll(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasContent)
        complexType->contentType()->setVariety(XsdComplexType::ContentType::Empty);

    tagValidator.finalize();
}

void XsdSchemaParser::parseComplexContentExtension(const XsdComplexType::Ptr &complexType)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Extension, this);

    validateElement(XsdTagScope::ComplexContentExtension);

    complexType->setDerivationMethod(XsdComplexType::DerivationExtension);

    // parse attributes
    const QString baseType = readQNameAttribute(QString::fromLatin1("base"), "extension");
    QXmlName typeName;
    convertName(baseType, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
    m_schemaResolver->addComplexBaseType(complexType, typeName, currentSourceLocation()); // add to resolver

    validateIdAttribute("extension");

    TagValidationHandler tagValidator(XsdTagScope::ComplexContentExtension, this, m_namePool);

    bool hasContent = false;
    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                complexType->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::OpenContent, token, namespaceToken)) {
                const XsdComplexType::OpenContent::Ptr openContent = parseOpenContent();
                complexType->contentType()->setOpenContent(openContent);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::All, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalAll(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, complexType);
                particle->setTerm(term);
                complexType->contentType()->setParticle(particle);
                hasContent = true;
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(complexType);
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                complexType->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                complexType->setAttributeWildcard(wildcard);
            } else if (isSchemaTag(XsdSchemaToken::Assert, token, namespaceToken)) {
                const XsdAssertion::Ptr assertion = parseAssertion(XsdSchemaToken::Assert, XsdTagScope::Assert);
                complexType->addAssertion(assertion);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasContent)
        complexType->contentType()->setVariety(XsdComplexType::ContentType::Empty);

    tagValidator.finalize();
}


XsdAssertion::Ptr XsdSchemaParser::parseAssertion(const XsdSchemaToken::NodeName &nodeName, const XsdTagScope::Type &tag)
{
    const ElementNamespaceHandler namespaceHandler(nodeName, this);

    validateElement(tag);

    const XsdAssertion::Ptr assertion(new XsdAssertion());

    // parse attributes

    const XsdXPathExpression::Ptr expression = readXPathExpression("assertion");
    assertion->setTest(expression);

    const QString test = readXPathAttribute(QString::fromLatin1("test"), XPath20, "assertion");
    expression->setExpression(test);

    validateIdAttribute("assertion");

    TagValidationHandler tagValidator(tag, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                assertion->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return assertion;
}

XsdComplexType::OpenContent::Ptr XsdSchemaParser::parseOpenContent()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::OpenContent, this);

    validateElement(XsdTagScope::OpenContent);

    const XsdComplexType::OpenContent::Ptr openContent(new XsdComplexType::OpenContent());

    if (hasAttribute(QString::fromLatin1("mode"))) {
        const QString mode = readAttribute(QString::fromLatin1("mode"));

        if (mode == QString::fromLatin1("none")) {
            m_defaultOpenContent->setMode(XsdComplexType::OpenContent::None);
        } else if (mode == QString::fromLatin1("interleave")) {
            m_defaultOpenContent->setMode(XsdComplexType::OpenContent::Interleave);
        } else if (mode == QString::fromLatin1("suffix")) {
            m_defaultOpenContent->setMode(XsdComplexType::OpenContent::Suffix);
        } else {
            attributeContentError("mode", "openContent", mode);
            return openContent;
        }
    } else {
        openContent->setMode(XsdComplexType::OpenContent::Interleave);
    }

    validateIdAttribute("openContent");

    TagValidationHandler tagValidator(XsdTagScope::OpenContent, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                openContent->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle;
                const XsdWildcard::Ptr wildcard = parseAny(particle);
                openContent->setWildcard(wildcard);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return openContent;
}

XsdModelGroup::Ptr XsdSchemaParser::parseNamedGroup()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Group, this);

    validateElement(XsdTagScope::NamedGroup);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    XsdModelGroup::Ptr group;

    QXmlName objectName;
    if (hasAttribute(QString::fromLatin1("name"))) {
        objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("group"));
    }

    validateIdAttribute("group");

    TagValidationHandler tagValidator(XsdTagScope::NamedGroup, this, m_namePool);

    XsdAnnotation::Ptr annotation;

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                annotation = parseAnnotation();
            } else if (isSchemaTag(XsdSchemaToken::All, token, namespaceToken)) {
                group = parseAll(modelGroup);
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                group = parseChoice(modelGroup);
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                group = parseSequence(modelGroup);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    group->setName(objectName);

    if (annotation)
        group->addAnnotation(annotation);

    return group;
}

XsdTerm::Ptr XsdSchemaParser::parseReferredGroup(const XsdParticle::Ptr &particle)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Group, this);

    validateElement(XsdTagScope::ReferredGroup);

    const XsdReference::Ptr reference(new XsdReference());
    reference->setType(XsdReference::ModelGroup);
    reference->setSourceLocation(currentSourceLocation());

    // parse attributes
    if (!parseMinMaxConstraint(particle, "group")) {
        return reference;
    }

    const QString value = readQNameAttribute(QString::fromLatin1("ref"), "group");
    QXmlName referenceName;
    convertName(value, NamespaceSupport::ElementName, referenceName); // translate qualified name into QXmlName
    reference->setReferenceName(referenceName);

    validateIdAttribute("group");

    TagValidationHandler tagValidator(XsdTagScope::ReferredGroup, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                reference->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return reference;
}

XsdModelGroup::Ptr XsdSchemaParser::parseAll(const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::All, this);

    validateElement(XsdTagScope::All);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::AllCompositor);

    validateIdAttribute("all");

    TagValidationHandler tagValidator(XsdTagScope::All, this, m_namePool);

    XsdParticle::List particles;
    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);

                if (particle->maximumOccursUnbounded() || particle->maximumOccurs() > 1) {
                    error(QtXmlPatterns::tr("%1 attribute of %2 element must be %3 or %4.")
                                           .arg(formatAttribute("maxOccurs"))
                                           .arg(formatElement("all"))
                                           .arg(formatData("0"))
                                           .arg(formatData("1")));
                    return modelGroup;
                }

                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdModelGroup::Ptr XsdSchemaParser::parseLocalAll(const XsdParticle::Ptr &particle, const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::All, this);

    validateElement(XsdTagScope::LocalAll);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::AllCompositor);

    // parse attributes
    if (!parseMinMaxConstraint(particle, "all")) {
        return modelGroup;
    }
    if (particle->maximumOccursUnbounded() || particle->maximumOccurs() != 1) {
        error(QtXmlPatterns::tr("%1 attribute of %2 element must have a value of %3.")
                               .arg(formatAttribute("maxOccurs"))
                               .arg(formatElement("all"))
                               .arg(formatData("1")));
        return modelGroup;
    }
    if (particle->minimumOccurs() != 0 && particle->minimumOccurs() != 1) {
        error(QtXmlPatterns::tr("%1 attribute of %2 element must have a value of %3 or %4.")
                               .arg(formatAttribute("minOccurs"))
                               .arg(formatElement("all"))
                               .arg(formatData("0"))
                               .arg(formatData("1")));
        return modelGroup;
    }

    validateIdAttribute("all");

    TagValidationHandler tagValidator(XsdTagScope::LocalAll, this, m_namePool);

    XsdParticle::List particles;
    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);

                if (particle->maximumOccursUnbounded() || particle->maximumOccurs() > 1) {
                    error(QtXmlPatterns::tr("%1 attribute of %2 element must have a value of %3 or %4.")
                                           .arg(formatAttribute("maxOccurs"))
                                           .arg(formatElement("all"))
                                           .arg(formatData("0"))
                                           .arg(formatData("1")));
                    return modelGroup;
                }

                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdModelGroup::Ptr XsdSchemaParser::parseChoice(const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Choice, this);

    validateElement(XsdTagScope::Choice);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::ChoiceCompositor);

    validateIdAttribute("choice");

    XsdParticle::List particles;

    TagValidationHandler tagValidator(XsdTagScope::Choice, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                m_schemaResolver->addAllGroupCheck(term);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseAny(particle);
                particle->setTerm(term);
                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdModelGroup::Ptr XsdSchemaParser::parseLocalChoice(const XsdParticle::Ptr &particle, const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Choice, this);

    validateElement(XsdTagScope::LocalChoice);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::ChoiceCompositor);

    // parse attributes
    if (!parseMinMaxConstraint(particle, "choice")) {
        return modelGroup;
    }

    validateIdAttribute("choice");

    XsdParticle::List particles;

    TagValidationHandler tagValidator(XsdTagScope::LocalChoice, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                m_schemaResolver->addAllGroupCheck(term);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseAny(particle);
                particle->setTerm(term);
                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdModelGroup::Ptr XsdSchemaParser::parseSequence(const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Sequence, this);

    validateElement(XsdTagScope::Sequence);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::SequenceCompositor);

    validateIdAttribute("sequence");

    XsdParticle::List particles;

    TagValidationHandler tagValidator(XsdTagScope::Sequence, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                m_schemaResolver->addAllGroupCheck(term);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseAny(particle);
                particle->setTerm(term);
                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdModelGroup::Ptr XsdSchemaParser::parseLocalSequence(const XsdParticle::Ptr &particle, const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Sequence, this);

    validateElement(XsdTagScope::LocalSequence);

    const XsdModelGroup::Ptr modelGroup(new XsdModelGroup());
    modelGroup->setCompositor(XsdModelGroup::SequenceCompositor);

    // parse attributes
    if (!parseMinMaxConstraint(particle, "sequence")) {
        return modelGroup;
    }

    validateIdAttribute("sequence");

    XsdParticle::List particles;

    TagValidationHandler tagValidator(XsdTagScope::LocalSequence, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                modelGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Element, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalElement(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Group, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseReferredGroup(particle);
                m_schemaResolver->addAllGroupCheck(term);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Choice, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalChoice(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Sequence, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseLocalSequence(particle, parent);
                particle->setTerm(term);
                particles.append(particle);
            } else if (isSchemaTag(XsdSchemaToken::Any, token, namespaceToken)) {
                const XsdParticle::Ptr particle(new XsdParticle());
                const XsdTerm::Ptr term = parseAny(particle);
                particle->setTerm(term);
                particles.append(particle);
            } else {
                parseUnknown();
            }
        }
    }

    modelGroup->setParticles(particles);

    tagValidator.finalize();

    return modelGroup;
}

XsdAttribute::Ptr XsdSchemaParser::parseGlobalAttribute()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Attribute, this);

    validateElement(XsdTagScope::GlobalAttribute);

    const XsdAttribute::Ptr attribute(new XsdAttribute());
    attribute->setScope(XsdAttribute::Scope::Ptr(new XsdAttribute::Scope()));
    attribute->scope()->setVariety(XsdAttribute::Scope::Global);

    if (hasAttribute(QString::fromLatin1("default")) && hasAttribute(QString::fromLatin1("fixed"))) {
        error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                               .arg(formatElement("attribute"))
                               .arg(formatAttribute("default"))
                               .arg(formatAttribute("fixed")));
        return attribute;
    }

    // parse attributes
    if (hasAttribute(QString::fromLatin1("default"))) {
        const QString value = readAttribute(QString::fromLatin1("default"));
        attribute->setValueConstraint(XsdAttribute::ValueConstraint::Ptr(new XsdAttribute::ValueConstraint()));
        attribute->valueConstraint()->setVariety(XsdAttribute::ValueConstraint::Default);
        attribute->valueConstraint()->setValue(value);
    } else if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        attribute->setValueConstraint(XsdAttribute::ValueConstraint::Ptr(new XsdAttribute::ValueConstraint()));
        attribute->valueConstraint()->setVariety(XsdAttribute::ValueConstraint::Fixed);
        attribute->valueConstraint()->setValue(value);
    }

    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("attribute"));
    if ((objectName.namespaceURI() == StandardNamespaces::xsi) &&
        (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("type")) &&
        (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("nil")) &&
        (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("schemaLocation")) &&
        (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("noNamespaceSchemaLocation"))) {

        error(QtXmlPatterns::tr("Content of %1 attribute of %2 element must not be from namespace %3.")
                               .arg(formatAttribute("name"))
                               .arg(formatElement("attribute"))
                               .arg(formatURI(CommonNamespaces::XSI)));
        return attribute;
    }
    if (m_namePool->stringForLocalName(objectName.localName()) == QString::fromLatin1("xmlns")) {
        error(QtXmlPatterns::tr("%1 attribute of %2 element must not be %3.")
                               .arg(formatAttribute("name"))
                               .arg(formatElement("attribute"))
                               .arg(formatData("xmlns")));
        return attribute;
    }
    attribute->setName(objectName);

    bool hasTypeAttribute = false;
    bool hasTypeSpecified = false;

    if (hasAttribute(QString::fromLatin1("type"))) {
        hasTypeAttribute = true;

        const QString type = readQNameAttribute(QString::fromLatin1("type"), "attribute");
        QXmlName typeName;
        convertName(type, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
        m_schemaResolver->addAttributeType(attribute, typeName, currentSourceLocation()); // add to resolver
        hasTypeSpecified = true;
    }

    validateIdAttribute("attribute");

    TagValidationHandler tagValidator(XsdTagScope::GlobalAttribute, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                attribute->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("attribute"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("type")));
                    break;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(attribute);
                attribute->setType(type);
                hasTypeSpecified = true;

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasTypeSpecified) {
        attribute->setType(BuiltinTypes::xsAnySimpleType); // default value
        return attribute;
    }

    tagValidator.finalize();

    return attribute;
}

XsdAttributeUse::Ptr XsdSchemaParser::parseLocalAttribute(const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Attribute, this);

    validateElement(XsdTagScope::LocalAttribute);

    bool hasRefAttribute = false;
    bool hasTypeAttribute = false;
    bool hasTypeSpecified = false;

    XsdAttributeUse::Ptr attributeUse;
    if (hasAttribute(QString::fromLatin1("ref"))) {
        const XsdAttributeReference::Ptr reference = XsdAttributeReference::Ptr(new XsdAttributeReference());
        reference->setType(XsdAttributeReference::AttributeUse);
        reference->setSourceLocation(currentSourceLocation());

        attributeUse = reference;
        hasRefAttribute = true;
    } else {
        attributeUse = XsdAttributeUse::Ptr(new XsdAttributeUse());
    }

    if (hasAttribute(QString::fromLatin1("default")) && hasAttribute(QString::fromLatin1("fixed"))) {
        error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                               .arg(formatElement("attribute"))
                               .arg(formatAttribute("default"))
                               .arg(formatAttribute("fixed")));
        return attributeUse;
    }

    if (hasRefAttribute) {
        if (hasAttribute(QString::fromLatin1("form"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("attribute"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("form")));
            return attributeUse;
        }
        if (hasAttribute(QString::fromLatin1("name"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("attribute"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("name")));
            return attributeUse;
        }
        if (hasAttribute(QString::fromLatin1("type"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("attribute"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("type")));
            return attributeUse;
        }
    }

    // parse attributes

    // default, fixed and use are handled by both, attribute use and attribute reference
    if (hasAttribute(QString::fromLatin1("default"))) {
        const QString value = readAttribute(QString::fromLatin1("default"));
        attributeUse->setValueConstraint(XsdAttributeUse::ValueConstraint::Ptr(new XsdAttributeUse::ValueConstraint()));
        attributeUse->valueConstraint()->setVariety(XsdAttributeUse::ValueConstraint::Default);
        attributeUse->valueConstraint()->setValue(value);
    } else if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        attributeUse->setValueConstraint(XsdAttributeUse::ValueConstraint::Ptr(new XsdAttributeUse::ValueConstraint()));
        attributeUse->valueConstraint()->setVariety(XsdAttributeUse::ValueConstraint::Fixed);
        attributeUse->valueConstraint()->setValue(value);
    }

    if (hasAttribute(QString::fromLatin1("use"))) {
        const QString value = readAttribute(QString::fromLatin1("use"));
        if (value != QString::fromLatin1("optional") &&
            value != QString::fromLatin1("prohibited") &&
            value != QString::fromLatin1("required")) {
            attributeContentError("use", "attribute", value);
            return attributeUse;
        }

        if (value == QString::fromLatin1("optional"))
            attributeUse->setUseType(XsdAttributeUse::OptionalUse);
        else if (value == QString::fromLatin1("prohibited"))
            attributeUse->setUseType(XsdAttributeUse::ProhibitedUse);
        else if (value == QString::fromLatin1("required"))
            attributeUse->setUseType(XsdAttributeUse::RequiredUse);

        if (attributeUse->valueConstraint() && attributeUse->valueConstraint()->variety() == XsdAttributeUse::ValueConstraint::Default && value != QString::fromLatin1("optional")) {
            error(QtXmlPatterns::tr("%1 attribute of %2 element must have the value %3 because the %4 attribute is set.")
                                   .arg(formatAttribute("use"))
                                   .arg(formatElement("attribute"))
                                   .arg(formatData("optional"))
                                   .arg(formatElement("default")));
            return attributeUse;
        }
    }

    const XsdAttribute::Ptr attribute(new XsdAttribute());

    attributeUse->setAttribute(attribute);
    m_componentLocationHash.insert(attribute, currentSourceLocation());

    attribute->setScope(XsdAttribute::Scope::Ptr(new XsdAttribute::Scope()));
    attribute->scope()->setVariety(XsdAttribute::Scope::Local);
    attribute->scope()->setParent(parent);

    // now make a difference between attribute reference and attribute use
    if (hasRefAttribute) {
        const QString reference = readQNameAttribute(QString::fromLatin1("ref"), "attribute");
        QXmlName referenceName;
        convertName(reference, NamespaceSupport::ElementName, referenceName);   // translate qualified name into QXmlName

        const XsdAttributeReference::Ptr attributeReference = attributeUse;
        attributeReference->setReferenceName(referenceName);
    } else {
        if (hasAttribute(QString::fromLatin1("name"))) {
            const QString attributeName = readNameAttribute("attribute");

            QXmlName objectName;
            if (hasAttribute(QString::fromLatin1("form"))) {
                const QString value = readAttribute(QString::fromLatin1("form"));
                if (value != QString::fromLatin1("qualified") && value != QString::fromLatin1("unqualified")) {
                    attributeContentError("form", "attribute", value);
                    return attributeUse;
                }

                if (value == QString::fromLatin1("qualified")) {
                    objectName = m_namePool->allocateQName(m_targetNamespace, attributeName);
                } else {
                    objectName = m_namePool->allocateQName(QString(), attributeName);
                }
            } else {
                if (m_attributeFormDefault == QString::fromLatin1("qualified")) {
                    objectName = m_namePool->allocateQName(m_targetNamespace, attributeName);
                } else {
                    objectName = m_namePool->allocateQName(QString(), attributeName);
                }
            }

            if ((objectName.namespaceURI() == StandardNamespaces::xsi) &&
                (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("type")) &&
                (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("nil")) &&
                (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("schemaLocation")) &&
                (m_namePool->stringForLocalName(objectName.localName()) != QString::fromLatin1("noNamespaceSchemaLocation"))) {

                error(QtXmlPatterns::tr("Content of %1 attribute of %2 element must not be from namespace %3.")
                                       .arg(formatAttribute("name"))
                                       .arg(formatElement("attribute"))
                                       .arg(formatURI(CommonNamespaces::XSI)));
                return attributeUse;
            }
            if (m_namePool->stringForLocalName(objectName.localName()) == QString::fromLatin1("xmlns")) {
                error(QtXmlPatterns::tr("%1 attribute of %2 element must not be %3.")
                                       .arg(formatAttribute("name"))
                                       .arg(formatElement("attribute"))
                                       .arg(formatData("xmlns")));
                return attributeUse;
            }

            attribute->setName(objectName);
        }

        if (hasAttribute(QString::fromLatin1("type"))) {
            hasTypeAttribute = true;

            const QString type = readQNameAttribute(QString::fromLatin1("type"), "attribute");
            QXmlName typeName;
            convertName(type, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
            m_schemaResolver->addAttributeType(attribute, typeName, currentSourceLocation()); // add to resolver
            hasTypeSpecified = true;
        }

        if (attributeUse->valueConstraint()) {
            //TODO: check whether assigning the value constraint of the attribute use to the attribute is correct
            if (!attribute->valueConstraint())
                attribute->setValueConstraint(XsdAttribute::ValueConstraint::Ptr(new XsdAttribute::ValueConstraint()));

            attribute->valueConstraint()->setVariety((XsdAttribute::ValueConstraint::Variety)attributeUse->valueConstraint()->variety());
            attribute->valueConstraint()->setValue(attributeUse->valueConstraint()->value());
            attribute->valueConstraint()->setLexicalForm(attributeUse->valueConstraint()->lexicalForm());
        }
    }

    validateIdAttribute("attribute");

    TagValidationHandler tagValidator(XsdTagScope::LocalAttribute, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                attribute->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("attribute"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("type")));
                    break;
                }
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("attribute"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("ref")));
                    break;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(attribute);
                attribute->setType(type);
                hasTypeSpecified = true;

                // add it to list of anonymous types as well
                addAnonymousType(type);
            } else {
                parseUnknown();
            }
        }
    }

    if (!hasTypeSpecified) {
        attribute->setType(BuiltinTypes::xsAnySimpleType); // default value
    }

    tagValidator.finalize();

    return attributeUse;
}

XsdAttributeGroup::Ptr XsdSchemaParser::parseNamedAttributeGroup()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::AttributeGroup, this);

    validateElement(XsdTagScope::NamedAttributeGroup);

    const XsdAttributeGroup::Ptr attributeGroup(new XsdAttributeGroup());

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("attributeGroup"));
    attributeGroup->setName(objectName);

    validateIdAttribute("attributeGroup");

    TagValidationHandler tagValidator(XsdTagScope::NamedAttributeGroup, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                attributeGroup->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Attribute, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseLocalAttribute(attributeGroup);

                if (attributeUse->useType() == XsdAttributeUse::ProhibitedUse) {
                    warning(QtXmlPatterns::tr("Specifying use='prohibited' inside an attribute group has no effect."));
                } else {
                    attributeGroup->addAttributeUse(attributeUse);
                }
            } else if (isSchemaTag(XsdSchemaToken::AttributeGroup, token, namespaceToken)) {
                const XsdAttributeUse::Ptr attributeUse = parseReferredAttributeGroup();
                attributeGroup->addAttributeUse(attributeUse);
            } else if (isSchemaTag(XsdSchemaToken::AnyAttribute, token, namespaceToken)) {
                const XsdWildcard::Ptr wildcard = parseAnyAttribute();
                attributeGroup->setWildcard(wildcard);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return attributeGroup;
}

XsdAttributeUse::Ptr XsdSchemaParser::parseReferredAttributeGroup()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::AttributeGroup, this);

    validateElement(XsdTagScope::ReferredAttributeGroup);

    const XsdAttributeReference::Ptr attributeReference(new XsdAttributeReference());
    attributeReference->setType(XsdAttributeReference::AttributeGroup);
    attributeReference->setSourceLocation(currentSourceLocation());

    // parse attributes
    const QString reference = readQNameAttribute(QString::fromLatin1("ref"), "attributeGroup");
    QXmlName referenceName;
    convertName(reference, NamespaceSupport::ElementName, referenceName); // translate qualified name into QXmlName
    attributeReference->setReferenceName(referenceName);

    validateIdAttribute("attributeGroup");

    TagValidationHandler tagValidator(XsdTagScope::ReferredAttributeGroup, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                attributeReference->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return attributeReference;
}

XsdElement::Ptr XsdSchemaParser::parseGlobalElement()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Element, this);

    validateElement(XsdTagScope::GlobalElement);

    const XsdElement::Ptr element(new XsdElement());
    element->setScope(XsdElement::Scope::Ptr(new XsdElement::Scope()));
    element->scope()->setVariety(XsdElement::Scope::Global);

    bool hasTypeAttribute = false;
    bool hasTypeSpecified = false;
    bool hasSubstitutionGroup = false;

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("element"));
    element->setName(objectName);

    if (hasAttribute(QString::fromLatin1("abstract"))) {
        const QString abstract = readAttribute(QString::fromLatin1("abstract"));

        const Boolean::Ptr value = Boolean::fromLexical(abstract);
        if (value->hasError()) {
            attributeContentError("abstract", "element", abstract, BuiltinTypes::xsBoolean);
            return element;
        }

        element->setIsAbstract(value->as<Boolean>()->value());
    } else {
        element->setIsAbstract(false); // the default value
    }

    if (hasAttribute(QString::fromLatin1("default")) && hasAttribute(QString::fromLatin1("fixed"))) {
        error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                               .arg(formatElement("element"))
                               .arg(formatAttribute("default"))
                               .arg(formatAttribute("fixed")));
        return element;
    }

    if (hasAttribute(QString::fromLatin1("default"))) {
        const QString value = readAttribute(QString::fromLatin1("default"));
        element->setValueConstraint(XsdElement::ValueConstraint::Ptr(new XsdElement::ValueConstraint()));
        element->valueConstraint()->setVariety(XsdElement::ValueConstraint::Default);
        element->valueConstraint()->setValue(value);
    } else if (hasAttribute(QString::fromLatin1("fixed"))) {
        const QString value = readAttribute(QString::fromLatin1("fixed"));
        element->setValueConstraint(XsdElement::ValueConstraint::Ptr(new XsdElement::ValueConstraint()));
        element->valueConstraint()->setVariety(XsdElement::ValueConstraint::Fixed);
        element->valueConstraint()->setValue(value);
    }

    element->setDisallowedSubstitutions(readBlockingConstraintAttribute(NamedSchemaComponent::ExtensionConstraint | NamedSchemaComponent::RestrictionConstraint | NamedSchemaComponent::SubstitutionConstraint, "element"));
    element->setSubstitutionGroupExclusions(readDerivationConstraintAttribute(SchemaType::ExtensionConstraint | SchemaType::RestrictionConstraint, "element"));

    if (hasAttribute(QString::fromLatin1("nillable"))) {
        const QString nillable = readAttribute(QString::fromLatin1("nillable"));

        const Boolean::Ptr value = Boolean::fromLexical(nillable);
        if (value->hasError()) {
            attributeContentError("nillable", "element", nillable, BuiltinTypes::xsBoolean);
            return element;
        }

        element->setIsNillable(value->as<Boolean>()->value());
    } else {
        element->setIsNillable(false); // the default value
    }

    if (hasAttribute(QString::fromLatin1("type"))) {
        const QString type = readQNameAttribute(QString::fromLatin1("type"), "element");
        QXmlName typeName;
        convertName(type, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
        m_schemaResolver->addElementType(element, typeName, currentSourceLocation()); // add to resolver

        hasTypeAttribute = true;
        hasTypeSpecified = true;
    }

    if (hasAttribute(QString::fromLatin1("substitutionGroup"))) {
        QList<QXmlName> elementNames;

        const QString value = readAttribute(QString::fromLatin1("substitutionGroup"));
        const QStringList substitutionGroups = value.split(QLatin1Char(' '), QString::SkipEmptyParts);
        if (substitutionGroups.isEmpty()) {
            attributeContentError("substitutionGroup", "element", value, BuiltinTypes::xsQName);
            return element;
        }

        for (int i = 0; i < substitutionGroups.count(); ++i) {
            const QString value = substitutionGroups.at(i).simplified();
            if (!XPathHelper::isQName(value)) {
                attributeContentError("substitutionGroup", "element", value, BuiltinTypes::xsQName);
                return element;
            }

            QXmlName elementName;
            convertName(value, NamespaceSupport::ElementName, elementName); // translate qualified name into QXmlName
            elementNames.append(elementName);
        }

        m_schemaResolver->addSubstitutionGroupAffiliation(element, elementNames, currentSourceLocation()); // add to resolver

        hasSubstitutionGroup = true;
    }

    validateIdAttribute("element");

    XsdAlternative::List alternatives;

    TagValidationHandler tagValidator(XsdTagScope::GlobalElement, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                element->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("type")));
                    return element;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(element);
                element->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::ComplexType, token, namespaceToken)) {
                if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("complexType"))
                                           .arg(formatAttribute("type")));
                    return element;
                }

                const XsdComplexType::Ptr type = parseLocalComplexType();
                type->setContext(element);
                element->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::Alternative, token, namespaceToken)) {
                const XsdAlternative::Ptr alternative = parseAlternative();
                alternatives.append(alternative);
            } else if (isSchemaTag(XsdSchemaToken::Unique, token, namespaceToken)) {
                const XsdIdentityConstraint::Ptr constraint = parseUnique();
                element->addIdentityConstraint(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Key, token, namespaceToken)) {
                const XsdIdentityConstraint::Ptr constraint = parseKey();
                element->addIdentityConstraint(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Keyref, token, namespaceToken)) {
                const XsdIdentityConstraint::Ptr constraint = parseKeyRef(element);
                element->addIdentityConstraint(constraint);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    if (!hasTypeSpecified) {
        if (hasSubstitutionGroup)
            m_schemaResolver->addSubstitutionGroupType(element);
        else
            element->setType(BuiltinTypes::xsAnyType);
    }

    if (!alternatives.isEmpty()) {
        element->setTypeTable(XsdElement::TypeTable::Ptr(new XsdElement::TypeTable()));

        for (int i = 0; i < alternatives.count(); ++i) {
            if (alternatives.at(i)->test())
                element->typeTable()->addAlternative(alternatives.at(i));

            if (i == (alternatives.count() - 1)) { // the final one
                if (!alternatives.at(i)->test()) {
                    element->typeTable()->setDefaultTypeDefinition(alternatives.at(i));
                } else {
                    const XsdAlternative::Ptr alternative(new XsdAlternative());
                    if (element->type())
                        alternative->setType(element->type());
                    else
                        m_schemaResolver->addAlternativeType(alternative, element); // add to resolver

                    element->typeTable()->setDefaultTypeDefinition(alternative);
                }
            }
        }
    }

    return element;
}

XsdTerm::Ptr XsdSchemaParser::parseLocalElement(const XsdParticle::Ptr &particle, const NamedSchemaComponent::Ptr &parent)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Element, this);

    validateElement(XsdTagScope::LocalElement);

    bool hasRefAttribute = false;
    bool hasTypeAttribute = false;
    bool hasTypeSpecified = false;

    XsdTerm::Ptr term;
    XsdElement::Ptr element;
    if (hasAttribute(QString::fromLatin1("ref"))) {
        term = XsdReference::Ptr(new XsdReference());
        hasRefAttribute = true;
    } else {
        term = XsdElement::Ptr(new XsdElement());
        element = term;
    }

    if (hasRefAttribute) {
        if (hasAttribute(QString::fromLatin1("name"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("name")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("block"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("block")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("nillable"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("nillable")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("default"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("default")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("fixed"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("fixed")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("form"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("form")));
            return term;
        } else if (hasAttribute(QString::fromLatin1("type"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("ref"))
                                   .arg(formatAttribute("type")));
            return term;
        }
    }

    // parse attributes
    if (!parseMinMaxConstraint(particle, "element")) {
        return element;
    }

    if (!hasAttribute(QString::fromLatin1("name")) && !hasAttribute(QString::fromLatin1("ref"))) {
        error(QtXmlPatterns::tr("%1 element must have either %2 or %3 attribute.")
                               .arg(formatElement("element"))
                               .arg(formatAttribute("name"))
                               .arg(formatAttribute("ref")));
        return element;
    }

    if (hasRefAttribute) {
        const QString ref = readQNameAttribute(QString::fromLatin1("ref"), "element");
        QXmlName referenceName;
        convertName(ref, NamespaceSupport::ElementName, referenceName); // translate qualified name into QXmlName

        const XsdReference::Ptr reference = term;
        reference->setReferenceName(referenceName);
        reference->setType(XsdReference::Element);
        reference->setSourceLocation(currentSourceLocation());
    } else {
        element->setScope(XsdElement::Scope::Ptr(new XsdElement::Scope()));
        element->scope()->setVariety(XsdElement::Scope::Local);
        element->scope()->setParent(parent.data());

        if (hasAttribute(QString::fromLatin1("name"))) {
            const QString elementName = readNameAttribute("element");

            QXmlName objectName;
            if (hasAttribute(QString::fromLatin1("form"))) {
                const QString value = readAttribute(QString::fromLatin1("form"));
                if (value != QString::fromLatin1("qualified") && value != QString::fromLatin1("unqualified")) {
                    attributeContentError("form", "element", value);
                    return element;
                }

                if (value == QString::fromLatin1("qualified")) {
                    objectName = m_namePool->allocateQName(m_targetNamespace, elementName);
                } else {
                    objectName = m_namePool->allocateQName(QString(), elementName);
                }
            } else {
                if (m_elementFormDefault == QString::fromLatin1("qualified")) {
                    objectName = m_namePool->allocateQName(m_targetNamespace, elementName);
                } else {
                    objectName = m_namePool->allocateQName(QString(), elementName);
                }
            }

            element->setName(objectName);
        }

        if (hasAttribute(QString::fromLatin1("nillable"))) {
            const QString nillable = readAttribute(QString::fromLatin1("nillable"));

            const Boolean::Ptr value = Boolean::fromLexical(nillable);
            if (value->hasError()) {
                attributeContentError("nillable", "element", nillable, BuiltinTypes::xsBoolean);
                return term;
            }

            element->setIsNillable(value->as<Boolean>()->value());
        } else {
            element->setIsNillable(false); // the default value
        }

        if (hasAttribute(QString::fromLatin1("default")) && hasAttribute(QString::fromLatin1("fixed"))) {
            error(QtXmlPatterns::tr("%1 element must not have %2 and %3 attribute together.")
                                   .arg(formatElement("element"))
                                   .arg(formatAttribute("default"))
                                   .arg(formatAttribute("fixed")));
            return element;
        }

        if (hasAttribute(QString::fromLatin1("default"))) {
            const QString value = readAttribute(QString::fromLatin1("default"));
            element->setValueConstraint(XsdElement::ValueConstraint::Ptr(new XsdElement::ValueConstraint()));
            element->valueConstraint()->setVariety(XsdElement::ValueConstraint::Default);
            element->valueConstraint()->setValue(value);
        } else if (hasAttribute(QString::fromLatin1("fixed"))) {
            const QString value = readAttribute(QString::fromLatin1("fixed"));
            element->setValueConstraint(XsdElement::ValueConstraint::Ptr(new XsdElement::ValueConstraint()));
            element->valueConstraint()->setVariety(XsdElement::ValueConstraint::Fixed);
            element->valueConstraint()->setValue(value);
        }

        if (hasAttribute(QString::fromLatin1("type"))) {
            const QString type = readQNameAttribute(QString::fromLatin1("type"), "element");
            QXmlName typeName;
            convertName(type, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
            m_schemaResolver->addElementType(element, typeName, currentSourceLocation()); // add to resolver

            hasTypeAttribute = true;
            hasTypeSpecified = true;
        }

        element->setDisallowedSubstitutions(readBlockingConstraintAttribute(NamedSchemaComponent::ExtensionConstraint | NamedSchemaComponent::RestrictionConstraint | NamedSchemaComponent::SubstitutionConstraint, "element"));
    }

    validateIdAttribute("element");

    XsdAlternative::List alternatives;

    TagValidationHandler tagValidator(XsdTagScope::LocalElement, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                term->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("ref")));
                    return term;
                } else if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("simpleType"))
                                           .arg(formatAttribute("type")));
                    return term;
                }

                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                type->setContext(element);
                element->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::ComplexType, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("complexType"))
                                           .arg(formatAttribute("ref")));
                    return term;
                } else if (hasTypeAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("complexType"))
                                           .arg(formatAttribute("type")));
                    return term;
                }

                const XsdComplexType::Ptr type = parseLocalComplexType();
                type->setContext(element);
                element->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::Alternative, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("alternative"))
                                           .arg(formatAttribute("ref")));
                    return term;
                }

                const XsdAlternative::Ptr alternative = parseAlternative();
                alternatives.append(alternative);
            } else if (isSchemaTag(XsdSchemaToken::Unique, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("unique"))
                                           .arg(formatAttribute("ref")));
                    return term;
                }

                const XsdIdentityConstraint::Ptr constraint = parseUnique();
                element->addIdentityConstraint(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Key, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("key"))
                                           .arg(formatAttribute("ref")));
                    return term;
                }

                const XsdIdentityConstraint::Ptr constraint = parseKey();
                element->addIdentityConstraint(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Keyref, token, namespaceToken)) {
                if (hasRefAttribute) {
                    error(QtXmlPatterns::tr("%1 element with %2 child element must not have a %3 attribute.")
                                           .arg(formatElement("element"))
                                           .arg(formatElement("keyref"))
                                           .arg(formatAttribute("ref")));
                    return term;
                }

                const XsdIdentityConstraint::Ptr constraint = parseKeyRef(element);
                element->addIdentityConstraint(constraint);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    if (!hasTypeSpecified && !hasRefAttribute)
        element->setType(BuiltinTypes::xsAnyType);

    if (!hasRefAttribute && !alternatives.isEmpty()) {
        element->setTypeTable(XsdElement::TypeTable::Ptr(new XsdElement::TypeTable()));

        for (int i = 0; i < alternatives.count(); ++i) {
            if (alternatives.at(i)->test())
                element->typeTable()->addAlternative(alternatives.at(i));

            if (i == (alternatives.count() - 1)) { // the final one
                if (!alternatives.at(i)->test()) {
                    element->typeTable()->setDefaultTypeDefinition(alternatives.at(i));
                } else {
                    const XsdAlternative::Ptr alternative(new XsdAlternative());
                    if (element->type())
                        alternative->setType(element->type());
                    else
                        m_schemaResolver->addAlternativeType(alternative, element); // add to resolver

                    element->typeTable()->setDefaultTypeDefinition(alternative);
                }
            }
        }
    }

    return term;
}

XsdIdentityConstraint::Ptr XsdSchemaParser::parseUnique()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Unique, this);

    validateElement(XsdTagScope::Unique);

    const XsdIdentityConstraint::Ptr constraint(new XsdIdentityConstraint());
    constraint->setCategory(XsdIdentityConstraint::Unique);

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("unique"));
    constraint->setName(objectName);

    validateIdAttribute("unique");

    TagValidationHandler tagValidator(XsdTagScope::Unique, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                constraint->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Selector, token, namespaceToken)) {
                parseSelector(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Field, token, namespaceToken)) {
                parseField(constraint);
            } else {
                parseUnknown();
            }
        }
    }

    // add constraint to schema for further checking
    addIdentityConstraint(constraint);

    tagValidator.finalize();

    return constraint;
}

XsdIdentityConstraint::Ptr XsdSchemaParser::parseKey()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Key, this);

    validateElement(XsdTagScope::Key);

    const XsdIdentityConstraint::Ptr constraint(new XsdIdentityConstraint());
    constraint->setCategory(XsdIdentityConstraint::Key);

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("key"));
    constraint->setName(objectName);

    validateIdAttribute("key");

    TagValidationHandler tagValidator(XsdTagScope::Key, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                constraint->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Selector, token, namespaceToken)) {
                parseSelector(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Field, token, namespaceToken)) {
                parseField(constraint);
            } else {
                parseUnknown();
            }
        }
    }

    // add constraint to schema for further checking
    addIdentityConstraint(constraint);

    tagValidator.finalize();

    return constraint;
}

XsdIdentityConstraint::Ptr XsdSchemaParser::parseKeyRef(const XsdElement::Ptr &element)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Keyref, this);

    validateElement(XsdTagScope::KeyRef);

    const XsdIdentityConstraint::Ptr constraint(new XsdIdentityConstraint());
    constraint->setCategory(XsdIdentityConstraint::KeyReference);

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("keyref"));
    constraint->setName(objectName);

    const QString refer = readQNameAttribute(QString::fromLatin1("refer"), "keyref");
    QXmlName referenceName;
    convertName(refer, NamespaceSupport::ElementName, referenceName); // translate qualified name into QXmlName
    m_schemaResolver->addKeyReference(element, constraint, referenceName, currentSourceLocation()); // add to resolver

    validateIdAttribute("keyref");

    TagValidationHandler tagValidator(XsdTagScope::KeyRef, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                constraint->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::Selector, token, namespaceToken)) {
                parseSelector(constraint);
            } else if (isSchemaTag(XsdSchemaToken::Field, token, namespaceToken)) {
                parseField(constraint);
            } else {
                parseUnknown();
            }
        }
    }

    // add constraint to schema for further checking
    addIdentityConstraint(constraint);

    tagValidator.finalize();

    return constraint;
}

void XsdSchemaParser::parseSelector(const XsdIdentityConstraint::Ptr &ptr)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Selector, this);

    validateElement(XsdTagScope::Selector);

    // parse attributes
    const XsdXPathExpression::Ptr expression = readXPathExpression("selector");

    const QString xpath = readXPathAttribute(QString::fromLatin1("xpath"), XPathSelector, "selector");
    expression->setExpression(xpath);

    ptr->setSelector(expression);

    validateIdAttribute("selector");

    TagValidationHandler tagValidator(XsdTagScope::Selector, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                expression->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

void XsdSchemaParser::parseField(const XsdIdentityConstraint::Ptr &ptr)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Field, this);

    validateElement(XsdTagScope::Field);

    // parse attributes
    const XsdXPathExpression::Ptr expression = readXPathExpression("field");

    const QString xpath = readXPathAttribute(QString::fromLatin1("xpath"), XPathField, "field");
    expression->setExpression(xpath);

    ptr->addField(expression);

    validateIdAttribute("field");

    TagValidationHandler tagValidator(XsdTagScope::Field, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                expression->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();
}

XsdAlternative::Ptr XsdSchemaParser::parseAlternative()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Alternative, this);

    validateElement(XsdTagScope::Alternative);

    const XsdAlternative::Ptr alternative(new XsdAlternative());

    bool hasTypeSpecified = false;

    if (hasAttribute(QString::fromLatin1("test"))) {
        const XsdXPathExpression::Ptr expression = readXPathExpression("alternative");

        const QString test = readXPathAttribute(QString::fromLatin1("test"), XPath20, "alternative");
        expression->setExpression(test);

        alternative->setTest(expression);
    }

    if (hasAttribute(QString::fromLatin1("type"))) {
        const QString type = readQNameAttribute(QString::fromLatin1("type"), "alternative");
        QXmlName typeName;
        convertName(type, NamespaceSupport::ElementName, typeName); // translate qualified name into QXmlName
        m_schemaResolver->addAlternativeType(alternative, typeName, currentSourceLocation()); // add to resolver

        hasTypeSpecified = true;
    }

    validateIdAttribute("alternative");

    TagValidationHandler tagValidator(XsdTagScope::Alternative, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                alternative->addAnnotation(annotation);
            } else if (isSchemaTag(XsdSchemaToken::SimpleType, token, namespaceToken)) {
                const XsdSimpleType::Ptr type = parseLocalSimpleType();
                alternative->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else if (isSchemaTag(XsdSchemaToken::ComplexType, token, namespaceToken)) {
                const XsdComplexType::Ptr type = parseLocalComplexType();
                alternative->setType(type);

                // add it to list of anonymous types as well
                addAnonymousType(type);

                hasTypeSpecified = true;
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    if (!hasTypeSpecified) {
        error(QtXmlPatterns::tr("%1 element must have either %2 attribute or %3 or %4 as child element.")
                               .arg(formatElement("alternative"))
                               .arg(formatAttribute("type"))
                               .arg(formatElement("simpleType"))
                               .arg(formatElement("complexType")));
        return alternative;
    }

    return alternative;
}

XsdNotation::Ptr XsdSchemaParser::parseNotation()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Notation, this);

    validateElement(XsdTagScope::Notation);

    const XsdNotation::Ptr notation(new XsdNotation());

    // parse attributes
    const QXmlName objectName = m_namePool->allocateQName(m_targetNamespace, readNameAttribute("notation"));
    notation->setName(objectName);

    bool hasOptionalAttribute = false;

    if (hasAttribute(QString::fromLatin1("public"))) {
        const QString value = readAttribute(QString::fromLatin1("public"));
        if (!value.isEmpty()) {
            const DerivedString<TypeToken>::Ptr publicId = DerivedString<TypeToken>::fromLexical(m_namePool, value);
            if (publicId->hasError()) {
                attributeContentError("public", "notation", value, BuiltinTypes::xsToken);
                return notation;
            }
            notation->setPublicId(publicId);
        }

        hasOptionalAttribute = true;
    }

    if (hasAttribute(QString::fromLatin1("system"))) {
        const QString value = readAttribute(QString::fromLatin1("system"));
        if (!isValidUri(value)) {
            attributeContentError("system", "notation", value, BuiltinTypes::xsAnyURI);
            return notation;
        }

        if (!value.isEmpty()) {
            const AnyURI::Ptr systemId = AnyURI::fromLexical(value);
            notation->setSystemId(systemId);
        }

        hasOptionalAttribute = true;
    }

    if (!hasOptionalAttribute) {
        error(QtXmlPatterns::tr("%1 element requires either %2 or %3 attribute.")
                               .arg(formatElement("notation"))
                               .arg(formatAttribute("public"))
                               .arg(formatAttribute("system")));
        return notation;
    }

    validateIdAttribute("notation");

    TagValidationHandler tagValidator(XsdTagScope::Notation, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isCharacters() || isEntityReference()) {
            if (!text().toString().trimmed().isEmpty()) {
                error(QtXmlPatterns::tr("Text or entity references not allowed inside %1 element").arg(formatElement("notation.")));
                return notation;
            }
        }

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                notation->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return notation;
}

XsdWildcard::Ptr XsdSchemaParser::parseAny(const XsdParticle::Ptr &particle)
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::Any, this);

    validateElement(XsdTagScope::Any);

    const XsdWildcard::Ptr wildcard(new XsdWildcard());

    // parse attributes
    if (!parseMinMaxConstraint(particle, "any")) {
        return wildcard;
    }

    if (hasAttribute(QString::fromLatin1("namespace"))) {
        const auto valueList = readAttribute(QString::fromLatin1("namespace")).split(QLatin1Char(' '), QString::SkipEmptyParts);
        const QSet<QString> values(valueList.cbegin(), valueList.cend());
        if ((values.contains(QString::fromLatin1("##any")) || values.contains(QString::fromLatin1("##other"))) && values.count() != 1) {
            error(QtXmlPatterns::tr("%1 attribute of %2 element must contain %3, %4 or a list of URIs.")
                                   .arg(formatAttribute("namespace"))
                                   .arg(formatElement("any"))
                                   .arg(formatData("##any"))
                                   .arg(formatData("##other")));
            return wildcard;
        }

        if (values.contains(QString::fromLatin1("##any"))) {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Any);
        } else if (values.contains(QString::fromLatin1("##other"))) {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Not);
            if (!m_targetNamespace.isEmpty())
                wildcard->namespaceConstraint()->setNamespaces(QSet<QString>() << m_targetNamespace);
            else
                wildcard->namespaceConstraint()->setNamespaces(QSet<QString>() << XsdWildcard::absentNamespace());
        } else {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Enumeration);
            QStringList newValues = values.values();

            // replace the ##targetNamespace entry
            for (int i = 0; i < newValues.count(); ++i) {
                if (newValues.at(i) == QString::fromLatin1("##targetNamespace")) {
                    if (!m_targetNamespace.isEmpty())
                        newValues[i] = m_targetNamespace;
                    else
                        newValues[i] = XsdWildcard::absentNamespace();
                } else if (newValues.at(i) == QString::fromLatin1("##local")) {
                    newValues[i] = XsdWildcard::absentNamespace();
                }
            }

            // check for invalid URIs
            for (int i = 0; i < newValues.count(); ++i) {
                const QString stringValue = newValues.at(i);
                if (stringValue == XsdWildcard::absentNamespace())
                    continue;

                if (!isValidUri(stringValue)) {
                    attributeContentError("namespace", "any", stringValue, BuiltinTypes::xsAnyURI);
                    return wildcard;
                }
            }

            wildcard->namespaceConstraint()->setNamespaces(QSet<QString>(newValues.cbegin(), newValues.cend()));
        }
    } else {
        wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Any);
    }

    if (hasAttribute(QString::fromLatin1("processContents"))) {
        const QString value = readAttribute(QString::fromLatin1("processContents"));
        if (value != QString::fromLatin1("lax") &&
            value != QString::fromLatin1("skip") &&
            value != QString::fromLatin1("strict")) {
            attributeContentError("processContents", "any", value);
            return wildcard;
        }

        if (value == QString::fromLatin1("lax")) {
            wildcard->setProcessContents(XsdWildcard::Lax);
        } else if (value == QString::fromLatin1("skip")) {
            wildcard->setProcessContents(XsdWildcard::Skip);
        } else if (value == QString::fromLatin1("strict")) {
            wildcard->setProcessContents(XsdWildcard::Strict);
        }
    } else {
        wildcard->setProcessContents(XsdWildcard::Strict);
    }

    validateIdAttribute("any");

    TagValidationHandler tagValidator(XsdTagScope::Any, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                wildcard->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return wildcard;
}

XsdWildcard::Ptr XsdSchemaParser::parseAnyAttribute()
{
    const ElementNamespaceHandler namespaceHandler(XsdSchemaToken::AnyAttribute, this);

    validateElement(XsdTagScope::AnyAttribute);

    const XsdWildcard::Ptr wildcard(new XsdWildcard());

    // parse attributes
    if (hasAttribute(QString::fromLatin1("namespace"))) {
        const auto valueList = readAttribute(QString::fromLatin1("namespace")).split(QLatin1Char(' '), QString::SkipEmptyParts);
        const QSet<QString> values(valueList.cbegin(), valueList.cend());
        if ((values.contains(QString::fromLatin1("##any")) || values.contains(QString::fromLatin1("##other"))) && values.count() != 1) {
            error(QtXmlPatterns::tr("%1 attribute of %2 element must contain %3, %4 or a list of URIs.")
                                   .arg(formatAttribute("namespace"))
                                   .arg(formatElement("anyAttribute"))
                                   .arg(formatData("##any"))
                                   .arg(formatData("##other")));
            return wildcard;
        }

        if (values.contains(QString::fromLatin1("##any"))) {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Any);
        } else if (values.contains(QString::fromLatin1("##other"))) {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Not);
            if (!m_targetNamespace.isEmpty())
                wildcard->namespaceConstraint()->setNamespaces(QSet<QString>() << m_targetNamespace);
            else
                wildcard->namespaceConstraint()->setNamespaces(QSet<QString>() << XsdWildcard::absentNamespace());
        } else {
            wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Enumeration);
            QStringList newValues = values.values();

            // replace the ##targetNamespace entry
            for (int i = 0; i < newValues.count(); ++i) {
                if (newValues.at(i) == QString::fromLatin1("##targetNamespace")) {
                    if (!m_targetNamespace.isEmpty())
                        newValues[i] = m_targetNamespace;
                    else
                        newValues[i] = XsdWildcard::absentNamespace();
                } else if (newValues.at(i) == QString::fromLatin1("##local")) {
                    newValues[i] = XsdWildcard::absentNamespace();
                }
            }

            // check for invalid URIs
            for (int i = 0; i < newValues.count(); ++i) {
                const QString stringValue = newValues.at(i);
                if (stringValue == XsdWildcard::absentNamespace())
                    continue;

                if (!isValidUri(stringValue)) {
                    attributeContentError("namespace", "anyAttribute", stringValue, BuiltinTypes::xsAnyURI);
                    return wildcard;
                }
            }

            wildcard->namespaceConstraint()->setNamespaces(QSet<QString>(newValues.cbegin(), newValues.cend()));
        }
    } else {
        wildcard->namespaceConstraint()->setVariety(XsdWildcard::NamespaceConstraint::Any);
    }

    if (hasAttribute(QString::fromLatin1("processContents"))) {
        const QString value = readAttribute(QString::fromLatin1("processContents"));
        if (value != QString::fromLatin1("lax") &&
            value != QString::fromLatin1("skip") &&
            value != QString::fromLatin1("strict")) {
            attributeContentError("processContents", "anyAttribute", value);
            return wildcard;
        }

        if (value == QString::fromLatin1("lax")) {
            wildcard->setProcessContents(XsdWildcard::Lax);
        } else if (value == QString::fromLatin1("skip")) {
            wildcard->setProcessContents(XsdWildcard::Skip);
        } else if (value == QString::fromLatin1("strict")) {
            wildcard->setProcessContents(XsdWildcard::Strict);
        }
    } else {
        wildcard->setProcessContents(XsdWildcard::Strict);
    }

    validateIdAttribute("anyAttribute");

    TagValidationHandler tagValidator(XsdTagScope::AnyAttribute, this, m_namePool);

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement()) {
            const XsdSchemaToken::NodeName token = XsdSchemaToken::toToken(name());
            const XsdSchemaToken::NodeName namespaceToken = XsdSchemaToken::toToken(namespaceUri());

            tagValidator.validate(token);

            if (isSchemaTag(XsdSchemaToken::Annotation, token, namespaceToken)) {
                const XsdAnnotation::Ptr annotation = parseAnnotation();
                wildcard->addAnnotation(annotation);
            } else {
                parseUnknown();
            }
        }
    }

    tagValidator.finalize();

    return wildcard;
}


void XsdSchemaParser::parseUnknownDocumentation()
{
    Q_ASSERT(isStartElement());
    m_namespaceSupport.pushContext();
    m_namespaceSupport.setPrefixes(namespaceDeclarations());

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement())
            parseUnknownDocumentation();
    }

    m_namespaceSupport.popContext();
}

void XsdSchemaParser::parseUnknown()
{
    Q_ASSERT(isStartElement());
    m_namespaceSupport.pushContext();
    m_namespaceSupport.setPrefixes(namespaceDeclarations());

    error(QtXmlPatterns::tr("%1 element is not allowed in this context.").arg(formatElement(name().toString())));

    while (!atEnd()) {
        readNext();

        if (isEndElement())
            break;

        if (isStartElement())
            parseUnknown();
    }

    m_namespaceSupport.popContext();
}

bool XsdSchemaParser::parseMinMaxConstraint(const XsdParticle::Ptr &particle, const char *elementName)
{
    if (hasAttribute(QString::fromLatin1("minOccurs"))) {
        const QString value = readAttribute(QString::fromLatin1("minOccurs"));

        DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
        if (integer->hasError()) {
            attributeContentError("minOccurs", elementName, value, BuiltinTypes::xsNonNegativeInteger);
            return false;
        } else {
            particle->setMinimumOccurs(integer->as< DerivedInteger<TypeNonNegativeInteger> >()->storedValue());
        }
    } else {
        particle->setMinimumOccurs(1);
    }

    if (hasAttribute(QString::fromLatin1("maxOccurs"))) {
        const QString value = readAttribute(QString::fromLatin1("maxOccurs"));

        if (value == QString::fromLatin1("unbounded")) {
            particle->setMaximumOccursUnbounded(true);
        } else {
            particle->setMaximumOccursUnbounded(false);
            DerivedInteger<TypeNonNegativeInteger>::Ptr integer = DerivedInteger<TypeNonNegativeInteger>::fromLexical(m_namePool, value);
            if (integer->hasError()) {
                attributeContentError("maxOccurs", elementName, value, BuiltinTypes::xsNonNegativeInteger);
                return false;
            } else {
                particle->setMaximumOccurs(integer->as< DerivedInteger<TypeNonNegativeInteger> >()->storedValue());
            }
        }
    } else {
        particle->setMaximumOccursUnbounded(false);
        particle->setMaximumOccurs(1);
    }

    if (!particle->maximumOccursUnbounded()) {
        if (particle->maximumOccurs() < particle->minimumOccurs()) {
            error(QtXmlPatterns::tr("%1 attribute of %2 element has larger value than %3 attribute.")
                                   .arg(formatAttribute("minOccurs"))
                                   .arg(formatElement(elementName))
                                   .arg(formatAttribute("maxOccurs")));
            return false;
        }
    }

    return true;
}

QSourceLocation XsdSchemaParser::currentSourceLocation() const
{
    QSourceLocation location;
    location.setLine(lineNumber());
    location.setColumn(columnNumber());
    location.setUri(m_documentURI);

    return location;
}

void XsdSchemaParser::convertName(const QString &qualifiedName, NamespaceSupport::NameType type, QXmlName &name)
{
    bool result = m_namespaceSupport.processName(qualifiedName, type, name);
    if (!result) {
        error(QtXmlPatterns::tr("Prefix of qualified name %1 is not defined.").arg(formatKeyword(qualifiedName)));
    }
}

QString XsdSchemaParser::readNameAttribute(const char *elementName)
{
    const QString value = readAttribute(QString::fromLatin1("name")).simplified();
    if (!QXmlUtils::isNCName(value)) {
        attributeContentError("name", elementName, value, BuiltinTypes::xsNCName);
        return QString();
    } else {
        return value;
    }
}

QString XsdSchemaParser::readQNameAttribute(const QString &typeAttribute, const char *elementName)
{
    const QString value = readAttribute(typeAttribute).simplified();
    if (!XPathHelper::isQName(value)) {
        attributeContentError(typeAttribute.toLatin1(), elementName, value, BuiltinTypes::xsQName);
        return QString();
    } else {
        return value;
    }
}

QString XsdSchemaParser::readNamespaceAttribute(const QString &attributeName, const char *elementName)
{
    const QString value = readAttribute(attributeName);
    if (value.isEmpty()) {
        attributeContentError(attributeName.toLatin1(), elementName, value, BuiltinTypes::xsAnyURI);
        return QString();
    }

    return value;
}

SchemaType::DerivationConstraints XsdSchemaParser::readDerivationConstraintAttribute(const SchemaType::DerivationConstraints &allowedConstraints, const char *elementName)
{
    // first convert the flags into strings for easier comparison
    QSet<QString> allowedContent;
    if (allowedConstraints & SchemaType::RestrictionConstraint)
        allowedContent.insert(QString::fromLatin1("restriction"));
    if (allowedConstraints & SchemaType::ExtensionConstraint)
        allowedContent.insert(QString::fromLatin1("extension"));
    if (allowedConstraints & SchemaType::ListConstraint)
        allowedContent.insert(QString::fromLatin1("list"));
    if (allowedConstraints & SchemaType::UnionConstraint)
        allowedContent.insert(QString::fromLatin1("union"));

    // read content from the attribute if available, otherwise use the default definitions from the schema tag
    QString content;
    if (hasAttribute(QString::fromLatin1("final"))) {
        content = readAttribute(QString::fromLatin1("final"));

        // split string into list to validate the content of the attribute
        const QStringList values = content.split(QLatin1Char(' '), QString::SkipEmptyParts);
        for (int i = 0; i < values.count(); i++) {
            const QString value = values.at(i);
            if (!allowedContent.contains(value) && (value != QString::fromLatin1("#all"))) {
                attributeContentError("final", elementName, value);
                return SchemaType::DerivationConstraints();
            }

            if ((value == QString::fromLatin1("#all")) && values.count() != 1) {
                error(QtXmlPatterns::tr("%1 attribute of %2 element must either contain %3 or the other values.")
                                       .arg(formatAttribute("final"))
                                       .arg(formatElement(elementName))
                                       .arg(formatData("#all")));
                return SchemaType::DerivationConstraints();
            }
        }
    } else {
        // content of the default value has been validated in parseSchema already
        content = m_finalDefault;
    }

    const auto &contentList = content.split(QLatin1Char(' '), QString::SkipEmptyParts);
    QSet<QString> contentSet(contentList.cbegin(), contentList.cend());

    // if the '#all' tag is defined, we return all allowed values
    if (contentSet.contains(QString::fromLatin1("#all"))) {
        return allowedConstraints;
    } else { // return the values from content set that intersects with the allowed values
        contentSet.intersect(allowedContent);

        SchemaType::DerivationConstraints constraints;

        if (contentSet.contains(QString::fromLatin1("restriction")))
            constraints |= SchemaType::RestrictionConstraint;
        if (contentSet.contains(QString::fromLatin1("extension")))
            constraints |= SchemaType::ExtensionConstraint;
        if (contentSet.contains(QString::fromLatin1("list")))
            constraints |= SchemaType::ListConstraint;
        if (contentSet.contains(QString::fromLatin1("union")))
            constraints |= SchemaType::UnionConstraint;

        return constraints;
    }
}

NamedSchemaComponent::BlockingConstraints XsdSchemaParser::readBlockingConstraintAttribute(const NamedSchemaComponent::BlockingConstraints &allowedConstraints, const char *elementName)
{
    // first convert the flags into strings for easier comparison
    QSet<QString> allowedContent;
    if (allowedConstraints & NamedSchemaComponent::RestrictionConstraint)
        allowedContent.insert(QString::fromLatin1("restriction"));
    if (allowedConstraints & NamedSchemaComponent::ExtensionConstraint)
        allowedContent.insert(QString::fromLatin1("extension"));
    if (allowedConstraints & NamedSchemaComponent::SubstitutionConstraint)
        allowedContent.insert(QString::fromLatin1("substitution"));

    // read content from the attribute if available, otherwise use the default definitions from the schema tag
    QString content;
    if (hasAttribute(QString::fromLatin1("block"))) {
        content = readAttribute(QString::fromLatin1("block"));

        // split string into list to validate the content of the attribute
        const QStringList values = content.split(QLatin1Char(' '), QString::SkipEmptyParts);
        for (int i = 0; i < values.count(); i++) {
            const QString value = values.at(i);
            if (!allowedContent.contains(value) && (value != QString::fromLatin1("#all"))) {
                attributeContentError("block", elementName, value);
                return NamedSchemaComponent::BlockingConstraints();
            }

            if ((value == QString::fromLatin1("#all")) && values.count() != 1) {
                error(QtXmlPatterns::tr("%1 attribute of %2 element must either contain %3 or the other values.")
                                       .arg(formatAttribute("block"))
                                       .arg(formatElement(elementName))
                                       .arg(formatData("#all")));
                return NamedSchemaComponent::BlockingConstraints();
            }
        }
    } else {
        // content of the default value has been validated in parseSchema already
        content = m_blockDefault;
    }

    const auto &contentList = content.split(QLatin1Char(' '), QString::SkipEmptyParts);
    QSet<QString> contentSet(contentList.cbegin(), contentList.cend());

    // if the '#all' tag is defined, we return all allowed values
    if (contentSet.contains(QString::fromLatin1("#all"))) {
        return allowedConstraints;
    } else { // return the values from content set that intersects with the allowed values
        contentSet.intersect(allowedContent);

        NamedSchemaComponent::BlockingConstraints constraints;

        if (contentSet.contains(QString::fromLatin1("restriction")))
            constraints |= NamedSchemaComponent::RestrictionConstraint;
        if (contentSet.contains(QString::fromLatin1("extension")))
            constraints |= NamedSchemaComponent::ExtensionConstraint;
        if (contentSet.contains(QString::fromLatin1("substitution")))
            constraints |= NamedSchemaComponent::SubstitutionConstraint;

        return constraints;
    }
}

XsdXPathExpression::Ptr XsdSchemaParser::readXPathExpression(const char *elementName)
{
    const XsdXPathExpression::Ptr expression(new XsdXPathExpression());

    const QList<QXmlName> namespaceBindings = m_namespaceSupport.namespaceBindings();
    QXmlName emptyName;
    for (int i = 0; i < namespaceBindings.count(); ++i) {
        if (namespaceBindings.at(i).prefix() == StandardPrefixes::empty)
            emptyName = namespaceBindings.at(i);
    }

    expression->setNamespaceBindings(namespaceBindings);

    QString xpathDefaultNamespace;
    if (hasAttribute(QString::fromLatin1("xpathDefaultNamespace"))) {
        xpathDefaultNamespace = readAttribute(QString::fromLatin1("xpathDefaultNamespace"));
        if (xpathDefaultNamespace != QString::fromLatin1("##defaultNamespace") &&
            xpathDefaultNamespace != QString::fromLatin1("##targetNamespace") &&
            xpathDefaultNamespace != QString::fromLatin1("##local")) {
            if (!isValidUri(xpathDefaultNamespace)) {
                attributeContentError("xpathDefaultNamespace", elementName, xpathDefaultNamespace, BuiltinTypes::xsAnyURI);
                return expression;
            }
        }
    } else {
        xpathDefaultNamespace = m_xpathDefaultNamespace;
    }

    AnyURI::Ptr namespaceURI;
    if (xpathDefaultNamespace == QString::fromLatin1("##defaultNamespace")) {
        if (!emptyName.isNull())
            namespaceURI = AnyURI::fromLexical(m_namePool->stringForNamespace(emptyName.namespaceURI()));
    } else if (xpathDefaultNamespace == QString::fromLatin1("##targetNamespace")) {
        if (!m_targetNamespace.isEmpty())
            namespaceURI = AnyURI::fromLexical(m_targetNamespace);
    } else if (xpathDefaultNamespace == QString::fromLatin1("##local")) {
        // it is absent
    } else {
        namespaceURI = AnyURI::fromLexical(xpathDefaultNamespace);
    }
    if (namespaceURI) {
        if (namespaceURI->hasError()) {
            attributeContentError("xpathDefaultNamespace", elementName, xpathDefaultNamespace, BuiltinTypes::xsAnyURI);
            return expression;
        }

        expression->setDefaultNamespace(namespaceURI);
    }

    //TODO: read the base uri if qmaintaining reader support it

    return expression;
}

QString XsdSchemaParser::readXPathAttribute(const QString &attributeName, XPathType type,  const char *elementName)
{
    const QString value = readAttribute(attributeName);
    if (value.isEmpty() || value.startsWith(QLatin1Char('/'))) {
        attributeContentError(attributeName.toLatin1(), elementName, value);
        return QString();
    }

    QXmlNamePool namePool(m_namePool.data());

    QXmlQuery::QueryLanguage language = QXmlQuery::XPath20;
    switch (type) {
        case XPath20: language = QXmlQuery::XPath20; break;
        case XPathSelector: language = QXmlQuery::XmlSchema11IdentityConstraintSelector; break;
        case XPathField: language = QXmlQuery::XmlSchema11IdentityConstraintField; break;
    };

    QXmlQuery query(language, namePool);
    QXmlQueryPrivate *queryPrivate = query.d;

    const QList<QXmlName> namespaceBindings = m_namespaceSupport.namespaceBindings();
    for (int i = 0; i < namespaceBindings.count(); ++i) {
        if (namespaceBindings.at(i).prefix() != StandardPrefixes::empty)
            queryPrivate->addAdditionalNamespaceBinding(namespaceBindings.at(i));
    }

    query.setQuery(value, m_documentURI);
    if (!query.isValid()) {
        attributeContentError(attributeName.toLatin1(), elementName, value);
        return QString();
    }

    return value;
}

void XsdSchemaParser::validateIdAttribute(const char *elementName)
{
    if (hasAttribute(QString::fromLatin1("id"))) {
        const QString value = readAttribute(QString::fromLatin1("id"));
        DerivedString<TypeID>::Ptr id = DerivedString<TypeID>::fromLexical(m_namePool, value);
        if (id->hasError()) {
            attributeContentError("id", elementName, value, BuiltinTypes::xsID);
        } else {
            if (m_idCache->hasId(value)) {
                error(QtXmlPatterns::tr("Component with ID %1 has been defined previously.").arg(formatData(value)));
            } else {
                m_idCache->addId(value);
            }
        }
    }
}

bool XsdSchemaParser::isSchemaTag(XsdSchemaToken::NodeName tag, XsdSchemaToken::NodeName token, XsdSchemaToken::NodeName namespaceToken) const
{
    return ((tag == token) && (namespaceToken == XsdSchemaToken::XML_NS_SCHEMA_URI));
}

void XsdSchemaParser::addElement(const XsdElement::Ptr &element)
{
    const QXmlName objectName = element->name(m_namePool);
    if (m_schema->element(objectName)) {
        error(QtXmlPatterns::tr("Element %1 already defined.").arg(formatElement(m_namePool->displayName(objectName))));
    } else {
        m_schema->addElement(element);
        m_componentLocationHash.insert(element, currentSourceLocation());
    }
}

void XsdSchemaParser::addAttribute(const XsdAttribute::Ptr &attribute)
{
    const QXmlName objectName = attribute->name(m_namePool);
    if (m_schema->attribute(objectName)) {
        error(QtXmlPatterns::tr("Attribute %1 already defined.").arg(formatAttribute(m_namePool->displayName(objectName))));
    } else {
        m_schema->addAttribute(attribute);
        m_componentLocationHash.insert(attribute, currentSourceLocation());
    }
}

void XsdSchemaParser::addType(const SchemaType::Ptr &type)
{
    // we don't import redefinitions of builtin types, that just causes problems
    if (m_builtinTypeNames.contains(type->name(m_namePool)))
        return;

    const QXmlName objectName = type->name(m_namePool);
    if (m_schema->type(objectName)) {
        error(QtXmlPatterns::tr("Type %1 already defined.").arg(formatType(m_namePool, objectName)));
    } else {
        m_schema->addType(type);
        if (type->isSimpleType())
            m_componentLocationHash.insert(XsdSimpleType::Ptr(type), currentSourceLocation());
        else
            m_componentLocationHash.insert(XsdComplexType::Ptr(type), currentSourceLocation());
    }
}

void XsdSchemaParser::addAnonymousType(const SchemaType::Ptr &type)
{
    m_schema->addAnonymousType(type);
    if (type->isSimpleType())
        m_componentLocationHash.insert(XsdSimpleType::Ptr(type), currentSourceLocation());
    else
        m_componentLocationHash.insert(XsdComplexType::Ptr(type), currentSourceLocation());
}

void XsdSchemaParser::addAttributeGroup(const XsdAttributeGroup::Ptr &group)
{
    const QXmlName objectName = group->name(m_namePool);
    if (m_schema->attributeGroup(objectName)) {
        error(QtXmlPatterns::tr("Attribute group %1 already defined.").arg(formatKeyword(m_namePool, objectName)));
    } else {
        m_schema->addAttributeGroup(group);
        m_componentLocationHash.insert(group, currentSourceLocation());
    }
}

void XsdSchemaParser::addElementGroup(const XsdModelGroup::Ptr &group)
{
    const QXmlName objectName = group->name(m_namePool);
    if (m_schema->elementGroup(objectName)) {
        error(QtXmlPatterns::tr("Element group %1 already defined.").arg(formatKeyword(m_namePool, objectName)));
    } else {
        m_schema->addElementGroup(group);
        m_componentLocationHash.insert(group, currentSourceLocation());
    }
}

void XsdSchemaParser::addNotation(const XsdNotation::Ptr &notation)
{
    const QXmlName objectName = notation->name(m_namePool);
    if (m_schema->notation(objectName)) {
        error(QtXmlPatterns::tr("Notation %1 already defined.").arg(formatKeyword(m_namePool, objectName)));
    } else {
        m_schema->addNotation(notation);
        m_componentLocationHash.insert(notation, currentSourceLocation());
    }
}

void XsdSchemaParser::addIdentityConstraint(const XsdIdentityConstraint::Ptr &constraint)
{
    const QXmlName objectName = constraint->name(m_namePool);
    if (m_schema->identityConstraint(objectName)) {
        error(QtXmlPatterns::tr("Identity constraint %1 already defined.").arg(formatKeyword(m_namePool, objectName)));
    } else {
        m_schema->addIdentityConstraint(constraint);
        m_componentLocationHash.insert(constraint, currentSourceLocation());
    }
}

void XsdSchemaParser::addFacet(const XsdFacet::Ptr &facet, XsdFacet::Hash &facets, const SchemaType::Ptr &type)
{
    // @see http://www.w3.org/TR/xmlschema-2/#src-single-facet-value
    if (facets.contains(facet->type())) {
        error(QtXmlPatterns::tr("Duplicated facets in simple type %1.").arg(formatType(m_namePool, type)));
        return;
    }

    facets.insert(facet->type(), facet);
}

QT_END_NAMESPACE
