/****************************************************************************
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** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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** This file is part of the QtXmlPatterns module of the Qt Toolkit.
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****************************************************************************/

#include "qboolean_p.h"
#include "qcommonvalues_p.h"
#include "qdynamiccontext_p.h"

#include "qexternalvariableloader_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

ExternalVariableLoader::~ExternalVariableLoader()
{
}


SequenceType::Ptr ExternalVariableLoader::announceExternalVariable(const QXmlName name,
                                                                   const SequenceType::Ptr &declaredType)
{
    Q_ASSERT(!name.isNull());
    Q_ASSERT(declaredType);
    Q_UNUSED(name); /* Needed when compiling in release mode. */
    Q_UNUSED(declaredType); /* Needed when compiling in release mode. */

    return SequenceType::Ptr();
}

Item::Iterator::Ptr ExternalVariableLoader::evaluateSequence(const QXmlName name,
                                                             const DynamicContext::Ptr &context)
{
    Q_ASSERT(!name.isNull());
    const Item item(evaluateSingleton(name, context));

    if(item)
        return makeSingletonIterator(item);
    else
        return CommonValues::emptyIterator;
}

Item ExternalVariableLoader::evaluateSingleton(const QXmlName name,
                                                    const DynamicContext::Ptr &context)
{
    Q_ASSERT(!name.isNull());
    return Boolean::fromValue(evaluateEBV(name, context));
}

bool ExternalVariableLoader::evaluateEBV(const QXmlName name,
                                         const DynamicContext::Ptr &context)
{
    Q_ASSERT(!name.isNull());
    return Boolean::evaluateEBV(evaluateSequence(name, context), context);
}

QT_END_NAMESPACE