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** This file is part of the QtXmlPatterns module of the Qt Toolkit.

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#include "qbuiltintypes_p.h"

#include "qcommonsequencetypes_p.h"

#include "qcommonvalues_p.h"

#include "qdistinctiterator_p.h"

#include "qebvextractor_p.h"

#include "qemptysequence_p.h"

#include "qgenericsequencetype_p.h"

#include "qindexofiterator_p.h"

#include "qinsertioniterator_p.h"

#include "qinteger_p.h"

#include "qremovaliterator_p.h"

#include "qsequencegeneratingfns_p.h"

#include "qsubsequenceiterator_p.h"

#include "qsequencefns_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

bool BooleanFN::evaluateEBV(const DynamicContext::Ptr &context) const

{

    return m_operands.first()->evaluateEBV(context);

}

Expression::Ptr BooleanFN::typeCheck(const StaticContext::Ptr &context,

                                     const SequenceType::Ptr &reqType)

{

    return EBVExtractor::typeCheck<FunctionCall>(context, reqType, this);

}

Item::Iterator::Ptr IndexOfFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    return Item::Iterator::Ptr(new IndexOfIterator(m_operands.first()->evaluateSequence(context),

                                                   m_operands.at(1)->evaluateSingleton(context),

                                                   comparator(), context,

                                                   ConstPtr(this)));

}

Expression::Ptr IndexOfFN::typeCheck(const StaticContext::Ptr &context,

                                     const SequenceType::Ptr &reqType)

{

    const Expression::Ptr me(FunctionCall::typeCheck(context, reqType));

    const ItemType::Ptr t1(m_operands.first()->staticType()->itemType());

    const ItemType::Ptr t2(m_operands.at(1)->staticType()->itemType());

    if(*CommonSequenceTypes::Empty == *t1 ||

       *CommonSequenceTypes::Empty == *t2)

    {

        return EmptySequence::create(this, context);

    }

    else

    {

        prepareComparison(fetchComparator(t1, t2, context));

        return me;

    }

}

Item::Iterator::Ptr DistinctValuesFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    return Item::Iterator::Ptr(new DistinctIterator(m_operands.first()->evaluateSequence(context),

                                                    comparator(),

                                                    ConstPtr(this),

                                                    context));

}

Expression::Ptr DistinctValuesFN::typeCheck(const StaticContext::Ptr &context,

                                            const SequenceType::Ptr &reqType)

{

    const Expression::Ptr me(FunctionCall::typeCheck(context, reqType));

    const ItemType::Ptr t1(m_operands.first()->staticType()->itemType());

    if(*CommonSequenceTypes::Empty == *t1)

        return EmptySequence::create(this, context);

    else if(!m_operands.first()->staticType()->cardinality().allowsMany())

        return m_operands.first();

    else if(BuiltinTypes::xsAnyAtomicType->xdtTypeMatches(t1))

        return me;

    else

    {

        prepareComparison(fetchComparator(t1, t1, context));

        return me;

    }

}

SequenceType::Ptr DistinctValuesFN::staticType() const

{

    const SequenceType::Ptr t(m_operands.first()->staticType());

    return makeGenericSequenceType(t->itemType(),

                                   t->cardinality().allowsMany() ? Cardinality::oneOrMore()

                                                                 : Cardinality::exactlyOne());

}

Item::Iterator::Ptr InsertBeforeFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    const Item::Iterator::Ptr target(m_operands.first()->evaluateSequence(context));

    const Item::Iterator::Ptr inserts(m_operands.at(2)->evaluateSequence(context));

    xsInteger position = m_operands.at(1)->evaluateSingleton(context).as<Numeric>()->toInteger();

    if(position < 1)

        position = 1;

    return Item::Iterator::Ptr(new InsertionIterator(target, position, inserts));

}

Item InsertBeforeFN::evaluateSingleton(const DynamicContext::Ptr &context) const

{

    return evaluateSequence(context)->next();

}

SequenceType::Ptr InsertBeforeFN::staticType() const

{

    const SequenceType::Ptr t1(m_operands.first()->staticType());

    const SequenceType::Ptr t2(m_operands.last()->staticType());

    return makeGenericSequenceType(t1->itemType() | t2->itemType(),

                                   t1->cardinality() + t2->cardinality());

}

Item::Iterator::Ptr RemoveFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    const xsInteger pos = m_operands.last()->evaluateSingleton(context).as<Numeric>()->toInteger();

    Item::Iterator::Ptr it(m_operands.first()->evaluateSequence(context));

    if(pos < 1)

        return it;

    return Item::Iterator::Ptr(new RemovalIterator(it, pos));

}

Item RemoveFN::evaluateSingleton(const DynamicContext::Ptr &context) const

{

    const xsInteger pos = m_operands.last()->evaluateSingleton(context).as<Numeric>()->toInteger();

    if(pos <= 1)

        return Item();

    return m_operands.first()->evaluateSingleton(context);

}

SequenceType::Ptr RemoveFN::staticType() const

{

    const SequenceType::Ptr opType(m_operands.first()->staticType());

    const Cardinality c(opType->cardinality());

    if(c.minimum() == 0)

        return makeGenericSequenceType(opType->itemType(), c);

    else

    {

        return makeGenericSequenceType(opType->itemType(),

                                       Cardinality::fromRange(c.minimum() - 1,

                                                              c.maximum()));

    }

}

Item::Iterator::Ptr ReverseFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    return m_operands.first()->evaluateSequence(context)->toReversed();

}

Expression::Ptr ReverseFN::typeCheck(const StaticContext::Ptr &context,

                                     const SequenceType::Ptr &reqType)

{

    if(m_operands.first()->staticType()->cardinality().allowsMany())

        return FunctionCall::typeCheck(context, reqType);

    else

        return m_operands.first()->typeCheck(context, reqType);

}

SequenceType::Ptr ReverseFN::staticType() const

{

    return m_operands.first()->staticType();

}

SubsequenceFN::SubsequenceFN() : m_hasTypeChecked(false)

{

}

Expression::Ptr SubsequenceFN::typeCheck(const StaticContext::Ptr &context,

                                         const SequenceType::Ptr &reqType)

{

    m_hasTypeChecked = true;

    return FunctionCall::typeCheck(context, reqType);

}

Item::Iterator::Ptr SubsequenceFN::evaluateSequence(const DynamicContext::Ptr &context) const

{

    Item::Iterator::Ptr it(m_operands.first()->evaluateSequence(context));

    xsInteger startingLoc = m_operands.at(1)->evaluateSingleton(context).as<Numeric>()->round()->toInteger();

    xsInteger length = -1;

    if(m_operands.count() == 3)

    {

        length = m_operands.last()->evaluateSingleton(context).as<Numeric>()->toInteger();

        if(startingLoc + length < 1 || (startingLoc > (startingLoc + length)))

            return CommonValues::emptyIterator;

    }

    /* F&O, 15.1.10, "If $startingLoc is zero or negative, the

     * subsequence includes items from the beginning of the $sourceSeq." */

    if(startingLoc < 1)

        startingLoc = 1;

    if(length < 1 && length != -1)

        return CommonValues::emptyIterator;

    return Item::Iterator::Ptr(new SubsequenceIterator(it, startingLoc, length));

}

Item SubsequenceFN::evaluateSingleton(const DynamicContext::Ptr &context) const

{

    return evaluateSequence(context)->next();

}

Expression::Ptr SubsequenceFN::compress(const StaticContext::Ptr &context)

{

    const Expression::Ptr me(FunctionCall::compress(context));

    if(me != this)

        return me;

    const Expression::Ptr lenArg(m_operands.value(2));

    if(lenArg && lenArg->isEvaluated())

    {

        const xsInteger length = lenArg->as<Literal>()->item().as<Numeric>()->round()->toInteger();

        if(length <= 0)

            return EmptySequence::create(this, context);

    }

    return me;

}

SequenceType::Ptr SubsequenceFN::staticType() const

{

    const SequenceType::Ptr opType(m_operands.first()->staticType());

    const Cardinality opCard(opType->cardinality());

    /* Optimization: we can do much stronger inference here. If the length is a

     * constant, we can constrain the range at least upwards of the

     * cardinality, for instance. */

    /* The subsequence(expr, 1, 1), add empty-sequence() to the static type.

     *

     * Note that we cannot do all these inferences before we've typechecked our

     * operands. The only known case of where our staticType() is called before

     * typeCheck() is through xmlpatternsview, although it wouldn't be

     * surprising if the more exotic paths can achieve that too.

     */

    if(m_hasTypeChecked &&

       m_operands.at(1)->isEvaluated()                                                      &&

       m_operands.count() == 3                                                              &&

       m_operands.at(2)->isEvaluated()                                                      &&

       m_operands.at(1)->as<Literal>()->item().as<Numeric>()->round()->toInteger() == 1     &&

       m_operands.at(2)->as<Literal>()->item().as<Numeric>()->round()->toInteger() == 1)

    {

        return makeGenericSequenceType(opType->itemType(),

                                       opCard.toWithoutMany());

    }

    else

    {

        return makeGenericSequenceType(opType->itemType(),

                                       opCard | Cardinality::zeroOrOne());

    }

}

Expression::Ptr DocFN::typeCheck(const StaticContext::Ptr &context,

                                 const SequenceType::Ptr &reqType)

{

    /* See the doxygen documentation for this function for the explanation

     * to why this implementation is here, as opposed to in

     * qsequencegeneratingfns.cpp. */

    Q_ASSERT(context);

    prepareStaticBaseURI(context);

    const Expression::Ptr uriOp(m_operands.first());

    if(!uriOp->isEvaluated())

        return Expression::Ptr(FunctionCall::typeCheck(context, reqType));

    const Item uriItem(uriOp->evaluateSingleton(context->dynamicContext()));

    if(!uriItem)

        return EmptySequence::create(this, context)->typeCheck(context, reqType); // TODO test this

    /* These two lines were previously in a separate function but are now duplicated

     * in DocFN::evaluateSingleton(), as part of a workaround for solaris-cc-64. */

    const QUrl mayRela(AnyURI::toQUrl<ReportContext::FODC0005>(uriItem.stringValue(), context, this));

    const QUrl uri(context->resolveURI(mayRela, staticBaseURI()));

    /* The URI is supplied statically, so, let's try to be clever. */

    Q_ASSERT_X(context->resourceLoader(), Q_FUNC_INFO,

               "No resource loader is set in the StaticContext.");

    m_type = context->resourceLoader()->announceDocument(uri, ResourceLoader::MayUse);

    if(m_type)

    {

        Q_ASSERT(CommonSequenceTypes::ZeroOrOneDocumentNode->matches(m_type));

        return Expression::Ptr(FunctionCall::typeCheck(context, reqType));

    }

    else

    {

        context->error(QtXmlPatterns::tr("It will not be possible to retrieve %1.").arg(formatURI(uri)),

                       ReportContext::FODC0002, this);

        return Expression::Ptr();

    }

}

QT_END_NAMESPACE