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#include "qitem_p.h"

#include "qbuiltintypes_p.h"

#include "qcardinalityverifier_p.h"

#include "qcommonsequencetypes_p.h"

#include "qemptysequence_p.h"

#include "qgenericsequencetype_p.h"

#include "qliteral_p.h"

#include "qpatternistlocale_p.h"

#include "qnamespaceresolver_p.h"

#include "qqnameconstructor_p.h"

#include "qqnamevalue_p.h"

#include "qatomicstring_p.h"

#include "qvalidationerror_p.h"

#include "qcastas_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

CastAs::CastAs(const Expression::Ptr &source,

               const SequenceType::Ptr &tType) : SingleContainer(source),

                                                 m_targetType(tType)

{

    Q_ASSERT(source);

    Q_ASSERT(tType);

    Q_ASSERT(!tType->cardinality().allowsMany());

    Q_ASSERT(tType->itemType()->isAtomicType());

}

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

{

    Q_ASSERT(context);

    const Item val(m_operand->evaluateSingleton(context));

    if(val)

        return cast(val, context);

    else

    {

        /* No item supplied, let's handle the cardinality part. */

        if(m_targetType->cardinality().allowsEmpty())

            return Item();

        else

        {

            Q_ASSERT(context);

            context->error(QtXmlPatterns::tr("Type error in cast, expected %1, "

                                             "received %2.")

                           .arg(formatType(Cardinality::exactlyOne()))

                           .arg(formatType(Cardinality::empty())),

                           ReportContext::XPTY0004, this);

            return Item();

        }

    }

}

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

                                  const SequenceType::Ptr &reqType)

{

    checkTargetType(context);

    const SequenceType::Ptr seqt(m_operand->staticType());

    ItemType::Ptr t(seqt->itemType());

    /* Special case xs:QName */

    if(BuiltinTypes::xsQName->xdtTypeMatches(m_targetType->itemType()))

    {

        /* Ok, We're casting to xs:QName. */

        if(m_operand->is(IDStringValue)) /* A valid combination, let's do the cast. */

            return castToQName(context)->typeCheck(context, reqType);

        else if(BuiltinTypes::xsQName->xdtTypeMatches(t))

            return m_operand->typeCheck(context, reqType);

        else if(seqt->cardinality().isEmpty() && m_targetType->cardinality().allowsEmpty())

            return EmptySequence::create(this, context);

        else if(!(seqt->cardinality().isEmpty() && !m_targetType->cardinality().allowsEmpty()))

        {

            context->error(QtXmlPatterns::tr("When casting to %1 or types "

                                             "derived from it, the source "

                                             "value must be of the same type, "

                                             "or it must be a string literal. "

                                             "Type %2 is not allowed.")

                           .arg(formatType(context->namePool(), BuiltinTypes::xsQName))

                           .arg(formatType(context->namePool(), seqt)),

                           ReportContext::XPTY0004, this);

            return Expression::Ptr(this);

        }

    }

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

    /* Type may have changed, such as that atomization has been applied. */

    t = m_operand->staticType()->itemType();

    if(m_targetType->itemType()->xdtTypeMatches(t) &&

       !BuiltinTypes::xsDayTimeDuration->xdtTypeMatches(t) &&

       !BuiltinTypes::xsYearMonthDuration->xdtTypeMatches(t))

    { /* At least casting is superflorous. */

        if(m_operand->staticType()->cardinality().isMatch(m_targetType->cardinality()))

            return m_operand; /* The whole cast expression is redundant. */

        else

        { /* Only cardinality check is needed, rewrite to CardinalityVerifier. */

            return Expression::Ptr(new CardinalityVerifier(m_operand,

                                                           m_targetType->cardinality(),

                                                           ReportContext::FORG0001));

        }

    }

    /* Let the CastingPlatform look up its AtomicCaster. */

    prepareCasting(context, t);

    return me;

}

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

{

    /* Simplify casts to itself. */

    if(*m_targetType->itemType() == *m_operand->staticType()->itemType())

        return m_operand->compress(context);

    else

        return SingleContainer::compress(context);

}

Expression::Ptr CastAs::castToQName(const StaticContext::Ptr &context) const

{

    /* Apply the whitespace facet by calling trimmed(). */

    /* We can assume m_operand is an Expression because this is a requirement

     * for casting to xs:QName. */

    const QString lexQName(m_operand->as<Literal>()->item().as<AtomicValue>()->stringValue().trimmed());

    const QXmlName

        expName(QNameConstructor::expandQName<StaticContext::Ptr,

                                              ReportContext::FORG0001,

                                              ReportContext::FONS0004>(lexQName,

                                                                       context,

                                                                       context->namespaceBindings(), this));

    return wrapLiteral(toItem(QNameValue::fromValue(context->namePool(), expName)), context, this);

}

SequenceType::Ptr CastAs::staticType() const

{

    if(m_operand->staticType()->cardinality().allowsEmpty())

        return m_targetType;

    else

        return makeGenericSequenceType(m_targetType->itemType(),

                                       Cardinality::exactlyOne());

}

SequenceType::List CastAs::expectedOperandTypes() const

{

    SequenceType::List result;

    if(m_targetType->cardinality().allowsEmpty())

        result.append(CommonSequenceTypes::ZeroOrOneAtomicType);

    else

        result.append(CommonSequenceTypes::ExactlyOneAtomicType);

    return result;

}

ExpressionVisitorResult::Ptr CastAs::accept(const ExpressionVisitor::Ptr &visitor) const

{

    return visitor->visit(this);

}

QT_END_NAMESPACE