/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/FloatingPoint.h"

#include "txExpr.h"

#include <math.h>

#include "txIXPathContext.h"

nsresult

txNumberExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)

{

    *aResult = nullptr;

    RefPtr<txAExprResult> exprRes;

    nsresult rv = mRightExpr->evaluate(aContext, getter_AddRefs(exprRes));

    NS_ENSURE_SUCCESS(rv, rv);

    double rightDbl = exprRes->numberValue();

    rv = mLeftExpr->evaluate(aContext, getter_AddRefs(exprRes));

    NS_ENSURE_SUCCESS(rv, rv);

    double leftDbl = exprRes->numberValue();

    double result = 0;

    switch (mOp) {

        case ADD:

            result = leftDbl + rightDbl;

            break;

        case SUBTRACT:

            result = leftDbl - rightDbl;

            break;

        case DIVIDE:

            if (rightDbl == 0) {

#if defined(XP_WIN)

                /* XXX MSVC miscompiles such that (NaN == 0) */

                if (mozilla::IsNaN(rightDbl))

                    result = mozilla::UnspecifiedNaN<double>();

                else

#endif

                if (leftDbl == 0 || mozilla::IsNaN(leftDbl))

                    result = mozilla::UnspecifiedNaN<double>();

                else if (mozilla::IsNegative(leftDbl) != mozilla::IsNegative(rightDbl))

                    result = mozilla::NegativeInfinity<double>();

                else

                    result = mozilla::PositiveInfinity<double>();

            }

            else

                result = leftDbl / rightDbl;

            break;

        case MODULUS:

            if (rightDbl == 0) {

                result = mozilla::UnspecifiedNaN<double>();

            }

            else {

#if defined(XP_WIN)

                /* Workaround MS fmod bug where 42 % (1/0) => NaN, not 42. */

                if (!mozilla::IsInfinite(leftDbl) && mozilla::IsInfinite(rightDbl))

                    result = leftDbl;

                else

#endif

                result = fmod(leftDbl, rightDbl);

            }

            break;

        case MULTIPLY:

            result = leftDbl * rightDbl;

            break;

    }

    return aContext->recycler()->getNumberResult(result, aResult);

} //-- evaluate

TX_IMPL_EXPR_STUBS_2(txNumberExpr, NUMBER_RESULT, mLeftExpr, mRightExpr)

bool

txNumberExpr::isSensitiveTo(ContextSensitivity aContext)

{

    return mLeftExpr->isSensitiveTo(aContext) ||

           mRightExpr->isSensitiveTo(aContext);

}

#ifdef TX_TO_STRING

void

txNumberExpr::toString(nsAString& str)

{

    mLeftExpr->toString(str);

    switch (mOp) {

        case ADD:

            str.AppendLiteral(" + ");

            break;

        case SUBTRACT:

            str.AppendLiteral(" - ");

            break;

        case DIVIDE:

            str.AppendLiteral(" div ");

            break;

        case MODULUS:

            str.AppendLiteral(" mod ");

            break;

        case MULTIPLY:

            str.AppendLiteral(" * ");

            break;

    }

    mRightExpr->toString(str);

}

#endif