#include "pch.h"
#include "TimeFunctions.h"
#pragma unmanaged

TimeFunctions::TimeFunctions()
{
	
}


UINT32  FileTime_to_POSIX(FILETIME ft)
{
	// takes the last modified date
	LARGE_INTEGER date, adjust;
	date.HighPart = ft.dwHighDateTime;
	date.LowPart = ft.dwLowDateTime;
	// 100-nanoseconds = milliseconds * 10000
	adjust.QuadPart = 11644473600000 * 10000;
	// removes the diff between 1970 and 1601
	date.QuadPart -= adjust.QuadPart;
	// converts back from 100-nanoseconds to seconds
	return (UINT32)(date.QuadPart / 10000000);
}

UINT32 UnixTimeNow() {
	FILETIME ft;
	GetSystemTimeAsFileTime(&ft);
	return FileTime_to_POSIX(ft);
}

/// <summary>
/// Filetime is 100nS since 1601 01 01 UTC Unix = seconds since 1970
/// </summary>
/// <param name="t"></param>
/// <param name="pft"></param>
void TimeFunctions::UnixTimeToFileTime(time_t t, LPFILETIME pft)
{
	ULONG64 ll = ((ULONG64)t * (ULONG64)10000000) + (ULONG64)116444736000000000;
	pft->dwLowDateTime = (DWORD)ll;
	pft->dwHighDateTime = ll >> 32;
}

 void TimeFunctions::UnixTimeToSystemTime(time_t t, LPSYSTEMTIME pst)
{
	FILETIME ft;
	UnixTimeToFileTime(t, &ft);
	FileTimeToSystemTime(&ft, pst);
}

 
 /// <summary>
 ///  converts MK2/MK3 time to FileTime
 /// </summary>
 /// <param name="epdTime">UTC</param>
 /// <param name="pft">UTC</param>
 /// <param name="isMK2"></param>
 //void TimeFunctions::EpdTimeToFileTime(UINT32 epdTime, LPFILETIME epdFileTime, bool isMK2)  //MK3
 //{
	// ULONG64 ll = (ULONG64)epdTime * (ULONG64)10000000;
	// if (isMK2) ll += (ULONG64) 116444736000000000; else ll += (ULONG64)125911584000000000; // 2000 base - 1601-1-1 (FT) Base
	// epdFileTime->dwLowDateTime = (DWORD)(ll & 0xffffffff);
	// epdFileTime->dwHighDateTime = ll >> 32;
 //}

 void TimeFunctions::Epd3TimeToFileTime(UINT32 epdTime, LPFILETIME epdFileTime)  //MK3
 {
	 ULONG64 ll = (ULONG64)epdTime * (ULONG64)10000000;
	 ll += (ULONG64)125911584000000000; // 2000 base - 1601-1-1 (FT) Base
	 epdFileTime->dwLowDateTime = (DWORD)(ll & 0xffffffff);
	 epdFileTime->dwHighDateTime = ll >> 32;
 }

 void TimeFunctions::FileTimeToEpdTime(FILETIME pft, INT32* t, bool isMK2)
 {
	 ULONG64 offset;
	 if (isMK2) offset = (ULONG64)116444736000000000; else offset = (ULONG64)125911584000000000;
	 LONGLONG ll = ((((LONGLONG)pft.dwHighDateTime << 32) + pft.dwLowDateTime) - offset) / 10000000;
	 *t = (DWORD)ll;
 }

 UINT32 TimeFunctions::NowToEpd3Time()
 {
	 ULONG64 offset;
	 offset = (ULONG64)125911584000000000;
	 SYSTEMTIME t;
	 GetSystemTime(&t); // is UTC !!
	 FILETIME ft;
	 SystemTimeToFileTime((const SYSTEMTIME*)&t, &ft);
	 LONGLONG ll = ((((LONGLONG)ft.dwHighDateTime << 32U) + ft.dwLowDateTime) - offset) / 10000000;
	 return (DWORD)ll;
 }


 //UINT32 TimeFunctions::NowToEpdTime(bool isMK2)
 //{
	// ULONG64 offset;
	// if (isMK2) offset = (ULONG64)116444736000000000; else offset = (ULONG64)125911584000000000;
	// SYSTEMTIME t;
	// GetSystemTime(&t); // is UTC !!
	// FILETIME ft;
	// SystemTimeToFileTime((const SYSTEMTIME*)&t, &ft);
	// LONGLONG ll = ((((LONGLONG)ft.dwHighDateTime << 32U) + ft.dwLowDateTime) - offset) / 10000000;
	// return (DWORD)ll;
 //}

 

 void TimeFunctions::EPD2PeakTimeToFiletime(DWORD EpdClock, DWORD EpdPeakTime, FILETIME* PeakFileTime) {
	 if (EpdPeakTime != 0xCDCDCDCD) {
		 UINT32 tm = EpdClock - EpdPeakTime;
		 GetSystemTimeAsFileTime(&lu.FT);
		 lu.LL -= UInt32x32To64(tm, 10000000);
		 *PeakFileTime = lu.FT;
	 } else
	 {
		 (*PeakFileTime).dwLowDateTime = (*PeakFileTime).dwHighDateTime = 0;
	 }
 }