/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: Time.hpp
    Date: 2021-6-17
    Author: Reece
***/
#pragma once

#if defined(AURORA_IS_POSIX_DERIVED)
    #include <time.h>
#endif

namespace Aurora::Time
{
#if defined(AURORA_PLATFORM_WIN32)

    static AuInt64 ConvertTimestamp(const FILETIME &ft)
    {
        ULARGE_INTEGER ull;
        ull.LowPart = ft.dwLowDateTime;
        ull.HighPart = ft.dwHighDateTime;
        return (ull.QuadPart - 126'435'537'000'000'000ull) / 10'000ULL;
    }

    static AuInt64 ConvertTimestamp(AuUInt64 timeIn)
    {
        return (126'435'537'000'000'000ull) + (AuUInt64(timeIn) * 10000ULL);
    }

    static AuInt64 ConvertTimestampNs(AuUInt64 timeIn)
    {
        return (126'435'537'000'000'000ull) + (AuUInt64(timeIn) / 100ULL);
    }

#elif defined(AURORA_IS_POSIX_DERIVED)

    static AuInt64 ConvertUnixTimespecToMs(const struct timespec &spec)
    {
        return ConvertUnixToAuroraMS(spec.tv_sec * 1000ULL + spec.tv_nsec / 1000000ULL);
    }

    static void ms2ts(struct timespec *ts, AuUInt64 ms)
    {
        ts->tv_sec  = ms / 1000;
        ts->tv_nsec = (ms % 1000) * 1000000;
    }

    static void ns2ts(struct timespec *ts, AuUInt64 ns)
    {
        ts->tv_sec  = ns / 1'000'000'000ull;
        ts->tv_nsec = ns % 1'000'000'000ull;
    }

    static void ms2tsabs(struct timespec *ts, unsigned long ms)
    {
        ::clock_gettime(CLOCK_MONOTONIC, ts);
     
        auto baseNS      = ((AuUInt64)ms * (AuUInt64)1'000'000) + (AuUInt64)ts->tv_nsec;
        auto remainderNS = (AuUInt64)baseNS % (AuUInt64)1'000'000'000;

        ts->tv_sec  += baseNS / 1'000'000'000ull;
        ts->tv_nsec = remainderNS;
    }

    static void ms2tsabsRealtime(struct timespec *ts, unsigned long ms)
    {
        ::clock_gettime(CLOCK_REALTIME, ts);

        auto baseNS      = ((AuUInt64)ms * (AuUInt64)1'000'000) + (AuUInt64)ts->tv_nsec;
        auto remainderNS = (AuUInt64)baseNS % (AuUInt64)1'000'000'000;

        ts->tv_sec  += baseNS / 1'000'000'000ull;
        ts->tv_nsec = remainderNS;
    }

    static void auabsns2ts(struct timespec *ts, unsigned long long ns)
    {
        auto baseNS      = ns + AuMSToNS<AuUInt64>(999'080'100'000);
        auto remainderNS = (AuUInt64)baseNS % (AuUInt64)1'000'000'000;

        ts->tv_sec  += baseNS / 1'000'000'000ull;
        ts->tv_nsec = remainderNS;
    }

    static void auabsms2ts(struct timespec *ts, unsigned long ms)
    {
        auabsns2ts(ts, AuMSToNS<AuUInt64>(ms));
    }

    static void ms2tvabs(struct timeval *tv, unsigned long ms)
    {
        timespec ts;
        ::clock_gettime(CLOCK_REALTIME, &ts);
     
        auto baseNS      = ((AuUInt64)ms * (AuUInt64)1'000'000) + (AuUInt64)ts.tv_nsec;
        auto remainderNS = (AuUInt64)baseNS % (AuUInt64)1'000'000'000;

        tv->tv_sec  = ts.tv_sec;
        tv->tv_sec  += baseNS / 1'000'000'000ull;
        tv->tv_usec = remainderNS / 1'000ull;
    }

    static void ms2tv(struct timeval *tv, unsigned long ms)
    {
        tv->tv_sec  = ms / 1'000ull;
        tv->tv_usec = (ms % 1'000ull) * 1'000ull;
    }

    static void ms2tsabsmono(struct timespec *ts, unsigned long ms)
    {
        clock_gettime(CLOCK_MONOTONIC, ts);
     
        auto baseNS      = ((AuUInt64)ms * (AuUInt64)1'000'000) + (AuUInt64)ts->tv_nsec;
        auto remainderNS = (AuUInt64)baseNS % (AuUInt64)1'000'000'000;

        ts->tv_sec  += baseNS / 1'000'000'000ull;
        ts->tv_nsec = remainderNS;
    }

#endif
}