/* ======================================================================== *\
!
! *
! * This file is part of MARS, the MAGIC Analysis and Reconstruction
! * Software. It is distributed to you in the hope that it can be a useful
! * and timesaving tool in analysing Data of imaging Cerenkov telescopes.
! * It is distributed WITHOUT ANY WARRANTY.
! *
! * Permission to use, copy, modify and distribute this software and its
! * documentation for any purpose is hereby granted without fee,
! * provided that the above copyright notice appear in all copies and
! * that both that copyright notice and this permission notice appear
! * in supporting documentation. It is provided "as is" without express
! * or implied warranty.
! *
!
!
!   Author(s): Thomas Bretz  12/2000 <mailto:tbretz@astro.uni-wuerzburg.de>
!
!   Copyright: MAGIC Software Development, 2000-2003
!
!
\* ======================================================================== */

/////////////////////////////////////////////////////////////////////////////
//
// MTime
//
// A generalized MARS time stamp
//
// WARNING: Be carefull changing this class. It is also used in the
//          MAGIC drive software cosy!
//
// Version 1:
// ----------
//  - first version
//
// Version 2:
// ----------
//  - removed fTimeStamp[2]
//
// Version 3:
// ----------
//  - removed fDurtaion - we may put it back when it is needed
//  - complete rewrite of the data members (old ones completely replaced)
//
/////////////////////////////////////////////////////////////////////////////
#include "MTime.h"

#include <iomanip>
#include <sys/time.h> // struct timeval

#include <TTime.h>

#include "MLog.h"
#include "MAstro.h"

ClassImp(MTime);

using namespace std;

const UInt_t MTime::kHour = 3600000;         // [ms] one hour
const UInt_t MTime::kDay  = MTime::kHour*24; // [ms] one day

// --------------------------------------------------------------------------
//
// Return date as year(y), month(m), day(d)
//
void MTime::GetDate(UShort_t &y, Byte_t &m, Byte_t &d) const
{
    MAstro::Mjd2Ymd((Long_t)fTime<0?fMjd-1:fMjd, y, m, d);
}

// --------------------------------------------------------------------------
//
// Return the time in the range [0h, 24h) = [0h0m0.000s - 23h59m59.999s]
//
void MTime::GetTime(Byte_t &h, Byte_t &m, Byte_t &s, UShort_t &ms) const
{
    Long_t tm = GetTime24();
    ms  = tm%1000;            // [ms]
    tm /= 1000;               // [s]
    s   = tm%60;              // [s]
    tm /= 60;                 // [m]
    m   = tm%60;              // [m]
    tm /= 60;                 // [h]
    h   = tm;                 // [h]
}

// --------------------------------------------------------------------------
//
//  Return time as MJD (=JD-24000000.5)
//
Double_t MTime::GetMjd() const
{
    return fMjd+(Double_t)(fNanoSec/1e6+(Long_t)fTime)/kDay;
}

// --------------------------------------------------------------------------
//
// Return a time which is expressed in milliseconds since 01/01/1995 0:00h
// This is compatible with root's definition used in gSystem->Now()
// and TTime.
// Note, gSystem->Now() returns local time, such that it may differ
// from GetRootTime() (if you previously called MTime::Now())
//
TTime MTime::GetRootTime() const
{
    return (ULong_t)((GetMjd()-49718)*kDay);
}

// --------------------------------------------------------------------------
//
// Return a time which is expressed in seconds since 01/01/1995 0:00h
// This is compatible with root's definition used in TAxis.
// Note, a TAxis always displayes (automatically) given times in
// local time (while here we return UTC) such, that you may encounter
// strange offsets. You can get rid of this by calling:
//    TAxis::SetTimeFormat("[your-format] %F1995-01-01 00:00:00");
//
Double_t MTime::GetAxisTime() const
{
    return (GetMjd()-49718)*kDay/1000;
}

// --------------------------------------------------------------------------
//
// Set a time expressed in MJD, Time of Day (eg. 23:12.779h expressed
// in milliseconds) and a nanosecond part.
//
Bool_t MTime::Set(UInt_t mjd, ULong_t ms, UInt_t ns)
{
    // [d]  mjd  (eg. 52320)
    // [ms] time (eg. 17h expressed in ms)
    // [ns] time (ns part of time)

    if (ms>kDay-1 || ns>999999)
        return kFALSE;

    const Bool_t am = ms < kHour*13; // day of sunrise?

    fMjd     = am ? mjd : mjd + 1;
    fTime    = (Long_t)(am ? ms  : ms-kDay);
    fNanoSec = ns;

    return kTRUE;
}

// --------------------------------------------------------------------------
//
// Set MTime to given MJD (eg. 52080.0915449892)
//
void MTime::SetMjd(Double_t m)
{
    const UInt_t   mjd  = (UInt_t)TMath::Floor(m);
    const Double_t frac = fmod(m, 1)*kDay; // [ms] Fraction of day
    const UInt_t   ns   = (UInt_t)fmod(frac*1e6, 1000000);

    Set(mjd, (ULong_t)TMath::Floor(frac), ns);
}

// --------------------------------------------------------------------------
//
// Set MTime to given time and date
//
Bool_t MTime::Set(UShort_t y, Byte_t m, Byte_t d, Byte_t h, Byte_t min, Byte_t s, UShort_t ms, UInt_t ns)
{
    if (h>23 || min>59 || s>59 || ms>999 || ns>999999)
        return kFALSE;

    const Int_t mjd = MAstro::Ymd2Mjd(y, m, d);
    if (mjd<0)
        return kFALSE;

    const ULong_t tm = ((((h*60+min)*60)+s)*1000)+ms;

    return Set(mjd, tm, ns);
}

// --------------------------------------------------------------------------
//
// Set MTime to time expressed in a 'struct timeval'
//
void MTime::Set(const struct timeval &tv)
{
    const UInt_t mjd = 1000*tv.tv_sec/kDay + 40587;
    const Long_t tm  = tv.tv_sec%(24*3600)*1000 + tv.tv_usec/1000;
    const UInt_t ms  = tv.tv_usec%1000;

    Set(mjd, tm, ms*1000);
}

// --------------------------------------------------------------------------
//
// Set MTime to time expressed as in CT1 PreProc files
//
void MTime::SetCT1Time(UInt_t mjd, UInt_t t1, UInt_t t0)
{
    // int   isecs_since_midday; // seconds passed since midday before sunset (JD of run start)
    // int   isecfrac_200ns;     // fractional part of isecs_since_midday
    // fTime->SetTime(isecfrac_200ns, isecs_since_midday);
    fNanoSec         = (200*t1)%1000000;
    const ULong_t ms = (200*t1)/1000000 + t0+12*kHour;

    fTime = (Long_t)(ms<13*kHour ? ms : ms-kDay);

    fMjd = mjd+1;
}

// --------------------------------------------------------------------------
//
// Set the time to the current system time. The timezone is ignored.
// If everything is set correctly you'll get UTC.
//
void MTime::Now()
{
#ifdef __LINUX__
    struct timeval tv;
    if (gettimeofday(&tv, NULL)<0)
        Reset();
    else
        Set(tv);
#else
    Reset();
#endif
}

// --------------------------------------------------------------------------
//
// Return contents as a TString of the form:
//   "yyyy/mm/dd hh:mm:ss.fff"
//
TString MTime::GetString() const
{
    UShort_t y, ms;
    Byte_t mon, d, h, m, s;

    GetDate(y, mon, d);
    GetTime(h, m, s, ms);

    return TString(Form("%4d/%02d/%02d %02d:%02d:%02d.%03d", y, mon, d, h, m, s, ms));
}

// --------------------------------------------------------------------------
//
// Return contents as a TString of the form:
//   "yyyymmdd_hhmmss"
//
TString MTime::GetFileName() const
{
    UShort_t y;
    Byte_t mon, d, h, m, s;

    GetDate(y, mon, d);
    GetTime(h, m, s);

    return TString(Form("%04d%02d%02d_%02d%02d%02d", y, mon, d, h, m, s));
}

// --------------------------------------------------------------------------
//
// Print MTime as string
//
void MTime::Print(Option_t *) const
{
    UShort_t yea, ms;
    Byte_t mon, day, h, m, s;

    GetDate(yea, mon, day);
    GetTime(h, m, s, ms);

    *fLog << GetDescriptor() << ": ";
    *fLog << GetString() << Form(" (+%dns)", fNanoSec) << endl;
} 

istream &MTime::ReadBinary(istream &fin)
{
    UShort_t y;
    Byte_t mon, d, h, m, s;

    fin.read((char*)&y,   2);
    fin.read((char*)&mon, 1);
    fin.read((char*)&d,   1);
    fin.read((char*)&h,   1);
    fin.read((char*)&m,   1);
    fin.read((char*)&s,   1); // Total=7

    Set(y, mon, d, h, m, s, 0);

    return fin;
}