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

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

 *

 * This file incorporates work covered by the following license notice:

 *

 *   Licensed to the Apache Software Foundation (ASF) under one or more

 *   contributor license agreements. See the NOTICE file distributed

 *   with this work for additional information regarding copyright

 *   ownership. The ASF licenses this file to you under the Apache

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 *   except in compliance with the License. You may obtain a copy of

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 */

#include <connectivity/dbconversion.hxx>

#include <com/sun/star/util/Date.hpp>

#include <com/sun/star/util/Time.hpp>

#include <com/sun/star/util/DateTime.hpp>

#include <rtl/character.hxx>

#include <rtl/math.hxx>

#include <sal/log.hxx>

#include <unotools/datetime.hxx>

#include <comphelper/date.hxx>

#include <o3tl/string_view.hxx>

#include <sstream>

#include <iomanip>

namespace

{

    const sal_Int64 nanoSecInSec = 1000000000;

    const sal_Int16 secInMin  = 60;

    const sal_Int16 minInHour = 60;

    const sal_Int64 secMask  = 1000000000;

    const sal_Int64 minMask  = 100000000000LL;

    const sal_Int64 hourMask = 10000000000000LL;

    const double fNanoSecondsPerDay = nanoSecInSec * secInMin * minInHour * 24.0;

    //  32767-12-31 in "(days since 0001-01-01) + 1" format

    const sal_Int32 maxDays =  11967896;

    // -32768-01-01 in "(days since 0001-01-01) + 1" format

    // Yes, I know it is currently unused. Will have to be used

    // when we implement negative years. Writing down the correct

    // value for future reference.

    // *** Please don't remove just because it is unused ***

    // Lionel Élie Mamane 2017-08-02

    // const sal_Int32 minDays = -11968270;

}

namespace dbtools

{

    using namespace ::com::sun::star::uno;

    using namespace ::com::sun::star::util;

    using namespace ::com::sun::star::sdb;

    using namespace ::com::sun::star::lang;

    using namespace ::com::sun::star::beans;

    css::util::Date const & DBTypeConversion::getStandardDate()

    {

        static css::util::Date STANDARD_DB_DATE(30,12,1899);

        return STANDARD_DB_DATE;

    }

    OUString DBTypeConversion::toDateString(const css::util::Date& rDate)

    {

        std::ostringstream ostr;

        using std::setw;

        ostr.fill('0');

        ostr << setw(4) << rDate.Year  << "-"

             << setw(2) << rDate.Month << "-"

             << setw(2) << rDate.Day;

        return OUString::createFromAscii(ostr.str());

    }

    OUString DBTypeConversion::toTimeStringS(const css::util::Time& rTime)

    {

        std::ostringstream ostr;

        using std::setw;

        ostr.fill('0');

        ostr << setw(2) << rTime.Hours   << ":"

             << setw(2) << rTime.Minutes << ":"

             << setw(2) << rTime.Seconds;

        return OUString::createFromAscii(ostr.str());

    }

    OUString DBTypeConversion::toTimeString(const css::util::Time& rTime)

    {

        std::ostringstream ostr;

        using std::setw;

        ostr.fill('0');

        ostr << setw(2) << rTime.Hours   << ":"

             << setw(2) << rTime.Minutes << ":"

             << setw(2) << rTime.Seconds << "."

             << setw(9) << rTime.NanoSeconds;

        return OUString::createFromAscii(ostr.str());

    }

    OUString DBTypeConversion::toDateTimeString(const css::util::DateTime& _rDateTime)

    {

        css::util::Date aDate(_rDateTime.Day,_rDateTime.Month,_rDateTime.Year);

        css::util::Time const aTime(_rDateTime.NanoSeconds, _rDateTime.Seconds,

                _rDateTime.Minutes, _rDateTime.Hours, _rDateTime.IsUTC);

        return toDateString(aDate) + " " + toTimeString(aTime);

    }

    css::util::Date DBTypeConversion::toDate(const sal_Int32 _nVal)

    {

        css::util::Date aReturn;

        aReturn.Day = static_cast<sal_uInt16>(_nVal % 100);

        aReturn.Month = static_cast<sal_uInt16>((_nVal  / 100) % 100);

        aReturn.Year = static_cast<sal_uInt16>(_nVal  / 10000);

        return aReturn;

    }

    css::util::Time DBTypeConversion::toTime(const sal_Int64 _nVal)

    {

        css::util::Time aReturn;

        sal_uInt64 unVal = static_cast<sal_uInt64>(_nVal >= 0 ? _nVal : -_nVal);

        aReturn.Hours = unVal / hourMask;

        aReturn.Minutes = (unVal / minMask) % 100;

        aReturn.Seconds = (unVal / secMask) % 100;

        aReturn.NanoSeconds = unVal % secMask;

        return aReturn;

    }

    sal_Int64 DBTypeConversion::getNsFromTime(const css::util::Time& rVal)

    {

        sal_Int32   nHour     = rVal.Hours;

        sal_Int32   nMin      = rVal.Minutes;

        sal_Int32   nSec      = rVal.Seconds;

        sal_Int32   nNanoSec  = rVal.NanoSeconds;

        return nNanoSec +

               nSec  * nanoSecInSec +

               nMin  * (secInMin * nanoSecInSec) +

               nHour * (minInHour * secInMin * nanoSecInSec);

    }

    static sal_Int32 implRelativeToAbsoluteNull(const css::util::Date& _rDate)

    {

        if (_rDate.Day == 0 && _rDate.Month == 0 && _rDate.Year == 0)

        {

            // 0000-00-00 is *NOT* a valid date and passing it to the date

            // conversion even when normalizing rightly asserts. Whatever we

            // return here, it will be wrong. The old before commit

            // 52ff16771ac160d27fd7beb78a4cfba22ad84f06 wrong implementation

            // calculated -365 for that, effectively that would be a date of

            // -0001-01-01 now but it was likely assumed that would be

            // 0000-00-01 or even 0000-00-00 instead. Try if we get away with 0

            // for -0001-12-31, the same that

            // comphelper::date::convertDateToDaysNormalizing()

            // would return if comphelper::date::normalize() wouldn't ignore

            // such "empty" date.

            return 0;

        }

        return comphelper::date::convertDateToDaysNormalizing( _rDate.Day, _rDate.Month, _rDate.Year);

    }

    sal_Int32 DBTypeConversion::toDays(const css::util::Date& _rVal, const css::util::Date& _rNullDate)

    {

        return implRelativeToAbsoluteNull(_rVal) - implRelativeToAbsoluteNull(_rNullDate);

    }

    double DBTypeConversion::toDouble(const css::util::Date& rVal, const css::util::Date& _rNullDate)

    {

        return static_cast<double>(toDays(rVal, _rNullDate));

    }

    double DBTypeConversion::toDouble(const css::util::Time& rVal)

    {

        return static_cast<double>(getNsFromTime(rVal)) / fNanoSecondsPerDay;

    }

    double DBTypeConversion::toDouble(const css::util::DateTime& _rVal, const css::util::Date& _rNullDate)

    {

        sal_Int64   nTime     = toDays(css::util::Date(_rVal.Day, _rVal.Month, _rVal.Year), _rNullDate);

        css::util::Time aTimePart;

        aTimePart.Hours             = _rVal.Hours;

        aTimePart.Minutes           = _rVal.Minutes;

        aTimePart.Seconds           = _rVal.Seconds;

        aTimePart.NanoSeconds       = _rVal.NanoSeconds;

        return static_cast<double>(nTime) + toDouble(aTimePart);

    }

    static void addDays(const sal_Int32 nDays, css::util::Date& _rDate)

    {

        sal_Int64 nTempDays = implRelativeToAbsoluteNull(_rDate);

        nTempDays += nDays;

        if ( nTempDays > maxDays )

        {

            _rDate.Day      = 31;

            _rDate.Month    = 12;

            _rDate.Year     = 9999;

        }

        // TODO: can we replace that check by minDays? Would allow dates BCE

        else if ( nTempDays <= 0 )

        {

            _rDate.Day      = 1;

            _rDate.Month    = 1;

            _rDate.Year     = 1;

        }

        else

            comphelper::date::convertDaysToDate( nTempDays, _rDate.Day, _rDate.Month, _rDate.Year );

    }

    static void subDays(const sal_Int32 nDays, css::util::Date& _rDate )

    {

        sal_Int64 nTempDays = implRelativeToAbsoluteNull(_rDate);

        nTempDays -= nDays;

        if ( nTempDays > maxDays )

        {

            _rDate.Day      = 31;

            _rDate.Month    = 12;

            _rDate.Year     = 9999;

        }

        // TODO: can we replace that check by minDays? Would allow dates BCE

        else if ( nTempDays <= 0 )

        {

            _rDate.Day      = 1;

            _rDate.Month    = 1;

            _rDate.Year     = 1;

        }

        else

            comphelper::date::convertDaysToDate( nTempDays, _rDate.Day, _rDate.Month, _rDate.Year );

    }

    css::util::Date DBTypeConversion::toDate(const double dVal, const css::util::Date& _rNullDate)

    {

        css::util::Date aRet = _rNullDate;

        if (dVal >= 0)

            addDays(static_cast<sal_Int32>(dVal),aRet);

        else

            subDays(static_cast<sal_uInt32>(-dVal),aRet);

            //  x -= (sal_uInt32)(-nDays);

        return aRet;

    }

    css::util::Time DBTypeConversion::toTime(const double dVal, short nDigits)

    {

        const double nDays = std::trunc(dVal);

        double fSeconds((dVal - nDays) * (fNanoSecondsPerDay / nanoSecInSec));

        fSeconds = ::rtl::math::round(fSeconds, nDigits);

        sal_Int64 nNS = fSeconds * nanoSecInSec;

        sal_Int16 nSign;

        if ( nNS < 0 )

        {

            nNS *= -1;

            nSign = -1;

        }

        else

            nSign = 1;

        css::util::Time aRet;

        // normalize time

        // we have to sal_Int32 here because otherwise we get an overflow

        sal_Int64 nNanoSeconds      = nNS;

        sal_Int32 nSeconds          = nNanoSeconds / nanoSecInSec;

        sal_Int32 nMinutes          = nSeconds / secInMin;

        aRet.NanoSeconds            = nNanoSeconds % nanoSecInSec;

        aRet.Seconds                = nSeconds % secInMin;

        aRet.Hours                  = nMinutes / minInHour;

        aRet.Minutes                = nMinutes % minInHour;

        // assemble time

        sal_Int64 nTime = nSign *

                          (aRet.NanoSeconds +

                           aRet.Seconds * secMask +

                           aRet.Minutes * minMask +

                           aRet.Hours   * hourMask);

        if(nTime < 0)

        {

            aRet.NanoSeconds  = nanoSecInSec-1;

            aRet.Seconds      = secInMin-1;

            aRet.Minutes      = minInHour-1;

            aRet.Hours        = 23;

        }

        return aRet;

    }

    css::util::DateTime DBTypeConversion::toDateTime(const double dVal, const css::util::Date& _rNullDate)

    {

        css::util::DateTime aRet;

        if (!std::isfinite(dVal))

        {

            SAL_WARN("connectivity.commontools", "DateTime has invalid value: " << dVal);

            return aRet;

        }

        css::util::Date aDate = toDate(dVal, _rNullDate);

        // there is not enough precision in a double to have both a date

        // and a time up to nanoseconds -> limit to microseconds to have

        // correct rounding, that is e.g. 13:00:00.000000000 instead of

        // 12:59:59.999999790

        css::util::Time aTime = toTime(dVal, 6);

        aRet.Day          = aDate.Day;

        aRet.Month        = aDate.Month;

        aRet.Year         = aDate.Year;

        aRet.NanoSeconds  = aTime.NanoSeconds;

        aRet.Minutes      = aTime.Minutes;

        aRet.Seconds      = aTime.Seconds;

        aRet.Hours        = aTime.Hours;

        return aRet;

    }

    css::util::Date DBTypeConversion::toDate(std::u16string_view _sSQLString)

    {

        // get the token out of a string

        static const sal_Unicode sDateSep = '-';

        sal_Int32 nIndex    = 0;

        sal_uInt16  nYear   = 0,

                    nMonth  = 0,

                    nDay    = 0;

        nYear   = static_cast<sal_uInt16>(o3tl::toInt32(o3tl::getToken(_sSQLString, 0,sDateSep,nIndex)));

        if(nIndex != -1)

        {

            nMonth = static_cast<sal_uInt16>(o3tl::toInt32(o3tl::getToken(_sSQLString, 0,sDateSep,nIndex)));

            if(nIndex != -1)

                nDay = static_cast<sal_uInt16>(o3tl::toInt32(o3tl::getToken(_sSQLString, 0,sDateSep,nIndex)));

        }

        return css::util::Date(nDay,nMonth,nYear);

    }

    css::util::DateTime DBTypeConversion::toDateTime(const OUString& _sSQLString)

    {

        //@see http://java.sun.com/j2se/1.4.2/docs/api/java/sql/Timestamp.html#valueOf(java.lang.String)

        //@see http://java.sun.com/j2se/1.4.2/docs/api/java/sql/Date.html#valueOf(java.lang.String)

        //@see http://java.sun.com/j2se/1.4.2/docs/api/java/sql/Time.html#valueOf(java.lang.String)

        // the date part

        css::util::Date aDate = toDate(_sSQLString);

        css::util::Time aTime;

        sal_Int32 nSeparation = _sSQLString.indexOf( ' ' );

        if ( -1 != nSeparation )

        {

            const sal_Unicode *p = _sSQLString.getStr() + nSeparation;

            const sal_Unicode *const begin = p;

            while (rtl::isAsciiWhiteSpace(*p)) { ++p; }

            nSeparation += p - begin;

            aTime = toTime( _sSQLString.subView( nSeparation ) );

        }

        return css::util::DateTime(aTime.NanoSeconds, aTime.Seconds, aTime.Minutes, aTime.Hours,

                        aDate.Day, aDate.Month, aDate.Year, false);

    }

    css::util::Time DBTypeConversion::toTime(std::u16string_view _sSQLString)

    {

        css::util::Time aTime;

        ::utl::ISO8601parseTime(_sSQLString, aTime);

        return aTime;

    }

}   // namespace dbtools

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */