// -*- C++ -*-

// Module:  Log4CPLUS

// File:    timehelper.h

// Created: 6/2003

// Author:  Tad E. Smith

//

//

// Copyright 2003-2017 Tad E. Smith

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//     http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

/** @file */

#ifndef LOG4CPLUS_HELPERS_TIME_HELPER_HEADER_

#define LOG4CPLUS_HELPERS_TIME_HELPER_HEADER_

#include <log4cplus/config.hxx>

#if defined (LOG4CPLUS_HAVE_PRAGMA_ONCE)

#pragma once

#endif

#include <log4cplus/tstring.h>

#if defined (LOG4CPLUS_HAVE_TIME_H)

#include <time.h>

#endif

#include <ctime>

#include <chrono>

namespace log4cplus {

namespace helpers {

using std::time_t;

using std::tm;

namespace chrono = std::chrono;

typedef chrono::system_clock Clock;

typedef chrono::duration<long long, std::micro> Duration;

typedef chrono::time_point<Clock, Duration> Time;

template <typename FromDuration>

inline

Time

time_cast (chrono::time_point<Clock, FromDuration> const & tp)

{

    return chrono::time_point_cast<Duration, Clock> (tp);

}

inline

Time

now ()

{

    return time_cast (Clock::now ());

}

inline

Time

from_time_t (time_t t_time)

{

    return time_cast (Clock::from_time_t (t_time));

}

inline

time_t

to_time_t (Time const & the_time)

{

    // This is based on <http://stackoverflow.com/a/17395137/341065>. It is

    // possible that to_time_t() returns rounded time and we want truncation.

    time_t time = Clock::to_time_t (the_time);

    auto const rounded_time = from_time_t (time);

    if (rounded_time > the_time)

        --time;

    return time;

}

LOG4CPLUS_EXPORT Time from_struct_tm (tm * t);

inline

Time

truncate_fractions (Time const & the_time)

{

    return from_time_t (to_time_t (the_time));

}

inline

long

microseconds_part (Time const & the_time)

{

    static_assert ((std::ratio_equal<Duration::period, std::micro>::value),

        "microseconds");

    // This is based on <http://stackoverflow.com/a/17395137/341065>

    return static_cast<long>(

        (the_time - from_time_t (to_time_t (the_time))).count ());

}

inline

Time

time_from_parts (time_t tv_sec, long tv_usec)

{

    return from_time_t (tv_sec) + chrono::microseconds (tv_usec);

}

/**

 * Populates <code>tm</code> using the <code>gmtime()</code>

 * function.

 */

LOG4CPLUS_EXPORT

void gmTime (tm* t, Time const &);

/**

 * Populates <code>tm</code> using the <code>localtime()</code>

 * function.

 */

LOG4CPLUS_EXPORT

void localTime (tm* t, Time const &);

/**

 * Returns a string with a "formatted time" specified by

 * <code>fmt</code>.  It used the <code>strftime()</code>

 * function to do this.

 *

 * Look at your platform's <code>strftime()</code> documentation

 * for the formatting options available.

 *

 * The following additional options are provided:<br>

 * <code>%q</code> - 3 character field that provides milliseconds

 * <code>%Q</code> - 7 character field that provides fractional

 * milliseconds.

 */

LOG4CPLUS_EXPORT

log4cplus::tstring getFormattedTime (log4cplus::tstring const & fmt,

    Time const & the_time, bool use_gmtime = false);

} // namespace helpers

} // namespace log4cplus

#endif // LOG4CPLUS_HELPERS_TIME_HELPER_HEADER_