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#include "qboolean_p.h"

#include "qbuiltintypes_p.h"

#include "qcommonsequencetypes_p.h"

#include "qemptysequence_p.h"

#include "qgenericsequencetype_p.h"

#include "qliteral_p.h"

#include "qpatternistlocale_p.h"

#include "qschemanumeric_p.h"

#include "quntypedatomicconverter_p.h"

#include "qarithmeticexpression_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

ArithmeticExpression::ArithmeticExpression(const Expression::Ptr &op1,

                                           const AtomicMathematician::Operator op,

                                           const Expression::Ptr &op2) : PairContainer(op1, op2)

                                                                       , m_op(op)

                                                                       , m_isCompat(false)

{

}

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

{

    const Item op1(m_operand1->evaluateSingleton(context));

    if(!op1)

        return Item();

    const Item op2(m_operand2->evaluateSingleton(context));

    if(!op2)

        return Item();

    return flexiblyCalculate(op1, m_op, op2, m_mather, context, this,

                             ReportContext::XPTY0004, m_isCompat);

}

/**

 * Since ArithmeticExpression::flexiblyCalculate() creates Expression instances

 * at runtime, we have the problem of having SourceLocationReflections for them

 * in the case that we run into a runtime error, since the locations are always

 * located at compile time.

 *

 * This class simply delegates the reflection over to an existing expression.

 *

 * I only managed to trigger this with "current() + 1", where current()

 * evaluates to an invalid representation for @c xs:double.

 *

 * @since 4.5

 * @author Frans Englich <frans.englich@nokia.com>

 */

class DelegatingReflectionExpression : public Literal

{

public:

    DelegatingReflectionExpression(const Item &item,

                                   const SourceLocationReflection *const reflection) : Literal(item)

                                                                                     , m_reflection(reflection)

    {

    }

    virtual const SourceLocationReflection *actualReflection() const

    {

        return m_reflection;

    }

private:

    const SourceLocationReflection *const m_reflection;

};

Item ArithmeticExpression::flexiblyCalculate(const Item &op1,

                                             const AtomicMathematician::Operator op,

                                             const Item &op2,

                                             const AtomicMathematician::Ptr &mather,

                                             const DynamicContext::Ptr &context,

                                             const SourceLocationReflection *const reflection,

                                             const ReportContext::ErrorCode code,

                                             const bool isCompat)

{

    if(mather)

        return mather->calculate(op1, op, op2, context);

    /* This is a very heavy code path. */

    Expression::Ptr a1(new DelegatingReflectionExpression(op1, reflection));

    Expression::Ptr a2(new DelegatingReflectionExpression(op2, reflection));

    const AtomicMathematician::Ptr ingela(fetchMathematician(a1, a2, op, true, context, reflection, code, isCompat));

    return ingela->calculate(a1->evaluateSingleton(context),

                             op,

                             a2->evaluateSingleton(context),

                             context);

}

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

                                                const SequenceType::Ptr &reqType)

{

    m_isCompat = context->compatModeEnabled();

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

    const ItemType::Ptr t1(m_operand1->staticType()->itemType());

    const ItemType::Ptr t2(m_operand2->staticType()->itemType());

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

       *CommonSequenceTypes::Empty == *t2)

    {

        return EmptySequence::create(this, context);

    }

    if(*BuiltinTypes::xsAnyAtomicType == *t1    ||

       *BuiltinTypes::xsAnyAtomicType == *t2    ||

       *BuiltinTypes::numeric == *t1            ||

       *BuiltinTypes::numeric == *t2)

    {

        /* The static type of (at least) one of the operands could not

         * be narrowed further than xs:anyAtomicType, so we do the operator

         * lookup at runtime. */

        return me;

    }

    m_mather = fetchMathematician(m_operand1, m_operand2, m_op, true, context, this,

                                  ReportContext::XPTY0004, m_isCompat);

    return me;

}

AtomicMathematician::Ptr

ArithmeticExpression::fetchMathematician(Expression::Ptr &op1,

                                         Expression::Ptr &op2,

                                         const AtomicMathematician::Operator op,

                                         const bool issueError,

                                         const ReportContext::Ptr &context,

                                         const SourceLocationReflection *const reflection,

                                         const ReportContext::ErrorCode code,

                                         const bool isCompat)

{

    ItemType::Ptr t1(op1->staticType()->itemType());

    ItemType::Ptr t2(op2->staticType()->itemType());

    if(BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t1)

       || (isCompat && (BuiltinTypes::xsString->xdtTypeMatches(t1)

                        || BuiltinTypes::xsDecimal->xdtTypeMatches(t1))))

    {

        op1 = Expression::Ptr(new UntypedAtomicConverter(op1, BuiltinTypes::xsDouble));

        /* The types might have changed, reload. */

        t1 = op1->staticType()->itemType();

    }

    if(BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t2)

       || (isCompat && (BuiltinTypes::xsString->xdtTypeMatches(t1)

                        || BuiltinTypes::xsDecimal->xdtTypeMatches(t1))))

    {

        op2 = Expression::Ptr(new UntypedAtomicConverter(op2, BuiltinTypes::xsDouble));

        /* The types might have changed, reload. */

        t2 = op2->staticType()->itemType();

    }

    const AtomicMathematicianLocator::Ptr locator

        (static_cast<const AtomicType *>(t1.data())->mathematicianLocator());

    if(!locator)

    {

        if(!issueError)

            return AtomicMathematician::Ptr();

        context->error(QtXmlPatterns::tr(

                       "Operator %1 cannot be used on type %2.")

                       .arg(formatKeyword(AtomicMathematician::displayName(op)))

                       .arg(formatType(context->namePool(), t1)),

                       code, reflection);

        return AtomicMathematician::Ptr();

    }

    const AtomicMathematician::Ptr comp

        (static_cast<const AtomicType *>(t2.data())->accept(locator, op, reflection));

    if(comp)

        return comp;

    if(!issueError)

        return AtomicMathematician::Ptr();

    context->error(QtXmlPatterns::tr("Operator %1 cannot be used on "

                                     "atomic values of type %2 and %3.")

                   .arg(formatKeyword(AtomicMathematician::displayName(op)))

                   .arg(formatType(context->namePool(), t1))

                   .arg(formatType(context->namePool(), t2)),

                   code, reflection);

    return AtomicMathematician::Ptr();

}

SequenceType::Ptr ArithmeticExpression::staticType() const

{

    Cardinality card;

    /* These variables are important because they ensure staticType() only

     * gets called once from this function. Before, this lead to strange

     * semi-infinite recursion involving many arithmetic expressions. */

    const SequenceType::Ptr st1(m_operand1->staticType());

    const SequenceType::Ptr st2(m_operand2->staticType());

    if(st1->cardinality().allowsEmpty() ||

       st2->cardinality().allowsEmpty())

    {

        card = Cardinality::zeroOrOne();

    }

    else

        card = Cardinality::exactlyOne();

    if(m_op == AtomicMathematician::IDiv)

        return makeGenericSequenceType(BuiltinTypes::xsInteger, card);

    const ItemType::Ptr t1(st1->itemType());

    const ItemType::Ptr t2(st2->itemType());

    ItemType::Ptr returnType;

    /* Please, make this beautiful? */

    if(BuiltinTypes::xsTime->xdtTypeMatches(t1) ||

       BuiltinTypes::xsDate->xdtTypeMatches(t1) ||

       BuiltinTypes::xsDateTime->xdtTypeMatches(t1))

    {

        if(BuiltinTypes::xsDuration->xdtTypeMatches(t2))

            returnType = t1;

        else

            returnType = BuiltinTypes::xsDayTimeDuration;

    }

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

    {

        if(m_op == AtomicMathematician::Div &&

           BuiltinTypes::xsYearMonthDuration->xdtTypeMatches(t2))

        {

            returnType = BuiltinTypes::xsDecimal;

        }

        else if(BuiltinTypes::numeric->xdtTypeMatches(t2))

            returnType = BuiltinTypes::xsYearMonthDuration;

        else

            returnType = t2;

    }

    else if(BuiltinTypes::xsYearMonthDuration->xdtTypeMatches(t2))

    {

        returnType = BuiltinTypes::xsYearMonthDuration;

    }

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

    {

        if(m_op == AtomicMathematician::Div &&

           BuiltinTypes::xsDayTimeDuration->xdtTypeMatches(t2))

        {

            returnType = BuiltinTypes::xsDecimal;

        }

        else if(BuiltinTypes::numeric->xdtTypeMatches(t2))

            returnType = BuiltinTypes::xsDayTimeDuration;

        else

            returnType = t2;

    }

    else if(BuiltinTypes::xsDayTimeDuration->xdtTypeMatches(t2))

    {

        returnType = BuiltinTypes::xsDayTimeDuration;

    }

    else if(BuiltinTypes::xsDouble->xdtTypeMatches(t1) ||

            BuiltinTypes::xsDouble->xdtTypeMatches(t2))

    {

        returnType = BuiltinTypes::xsDouble;

    }

    else if(BuiltinTypes::xsFloat->xdtTypeMatches(t1) ||

            BuiltinTypes::xsFloat->xdtTypeMatches(t2))

    {

        if(m_isCompat)

            returnType = BuiltinTypes::xsFloat;

        else

            returnType = BuiltinTypes::xsDouble;

    }

    else if(BuiltinTypes::xsInteger->xdtTypeMatches(t1) &&

            BuiltinTypes::xsInteger->xdtTypeMatches(t2))

    {

        if(m_isCompat)

            returnType = BuiltinTypes::xsDouble;

        else

        {

            /* "A div B  numeric  numeric  op:numeric-divide(A, B)

             * numeric; but xs:decimal if both operands are xs:integer" */

            if(m_op == AtomicMathematician::Div)

                returnType = BuiltinTypes::xsDecimal;

            else

                returnType = BuiltinTypes::xsInteger;

        }

    }

    else if(m_isCompat && (BuiltinTypes::xsInteger->xdtTypeMatches(t1) &&

                           BuiltinTypes::xsInteger->xdtTypeMatches(t2)))

    {

        returnType = BuiltinTypes::xsDouble;

    }

    else

    {

        /* If typeCheck() has been called, our operands conform to expectedOperandTypes(), and

         * the types are hence either xs:decimals, or xs:anyAtomicType(meaning the static type could

         * not be inferred), or empty-sequence(). So we use the union of the two types. The combinations

         * could also be wrong.*/

        returnType = t1 | t2;

        /* However, if we're called before typeCheck(), we could potentially have nodes, so we need to make

         * sure that the type is at least atomic. */

        if(!BuiltinTypes::xsAnyAtomicType->xdtTypeMatches(returnType))

            returnType = BuiltinTypes::xsAnyAtomicType;

    }

    return makeGenericSequenceType(returnType, card);

}

SequenceType::List ArithmeticExpression::expectedOperandTypes() const

{

    SequenceType::List result;

    result.append(CommonSequenceTypes::ZeroOrOneAtomicType);

    result.append(CommonSequenceTypes::ZeroOrOneAtomicType);

    return result;

}

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

{

    return visitor->visit(this);

}

QT_END_NAMESPACE