// 
// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
// 
// calendar -- 
// 
// Author           : Peter A. Buhr
// Created On       : Wed Mar 14 23:18:57 2018
// Last Modified By : Peter A. Buhr
// Last Modified On : Thu Mar 22 17:11:19 2018
// Update Count     : 495
// 

#pragma once

// http://en.cppreference.com/w/cpp/header/chrono
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r5.html#refcc

#include <time.h>
extern "C" {
#include <sys/time.h>
int snprintf( char * buf, size_t size, const char * fmt, ... );
}
#include <fstream>

enum {
	CLOCKGRAN = 15_000_000L,							// ALWAYS in nanoseconds, MUST BE less than 1 second
	TIMEGRAN = 1_000_000_000L							// nanosecond granularity, except for timeval
};


#if defined( REALTIME_POSIX )
#define tv_XSEC tv_nsec
#else
#define tv_XSEC tv_usec
#endif


#if defined( __linux__ )
// fake a few things
#define	CLOCK_REALTIME	0								// real (clock on the wall) time
#endif

// conversions for existing time types
static inline void ?{}( timeval & t ) {}
static inline void ?{}( timeval & t, time_t sec ) { t.tv_sec = sec; t.tv_usec = 0; }
static inline void ?{}( timeval & t, time_t sec, suseconds_t usec ) { t.tv_sec = sec; t.tv_usec = usec; }

static inline void ?{}( timespec & t ) {}
static inline void ?{}( timespec & t, time_t sec ) { t.tv_sec = sec; t.tv_nsec = 0; }
static inline void ?{}( timespec & t, time_t sec, __syscall_slong_t nsec ) { t.tv_sec = sec; t.tv_nsec = nsec; }

static inline char * ctime( time_t tp ) { char * buf = ctime( &tp ); buf[24] = '\0'; return buf; }
static inline char * ctime_r( time_t tp, char * buf ) { ctime_r( &tp, buf ); buf[24] = '\0'; return buf; }
static inline tm * gmtime( time_t tp ) { return gmtime( &tp ); }
static inline tm * gmtime_r( time_t tp, tm * result ) { return gmtime_r( &tp, result ); }
static inline tm * localtime( time_t tp ) { return localtime( &tp ); }
static inline tm * localtime_r( time_t tp, tm * result ) { return localtime_r( &tp, result ); }


//######################### Duration #########################

struct Duration {
	int64_t tv;
};

static inline void ?{}( Duration & dur ) with( dur ) { tv = 0; }
static inline void ?{}( Duration & dur, Duration d ) with( dur ) { tv = d.tv; }

static inline void ?{}( Duration & dur, timeval t ) with( dur ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_usec * 1000;
} // Duration

static inline void ?{}( Duration & dur, timespec t ) with( dur ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_nsec;
} // Duration

static inline Duration ?=?( Duration & dur, timeval t ) with( dur ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_usec * 1000;
	return dur;
} // ?=?

static inline Duration ?=?( Duration & dur, timespec t ) with( dur ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_nsec;
	return dur;
} // ?=? timespec

static inline void ?{}( timeval & t, Duration dur ) with( dur ) {
	t.tv_sec = tv / TIMEGRAN;							// seconds
	t.tv_usec = tv % TIMEGRAN / ( TIMEGRAN / 1000000L ); // microseconds
} // ?{}

static inline void ?{}( timespec & t, Duration dur ) with( dur ) {
	t.tv_sec = tv / TIMEGRAN;							// seconds
	t.tv_nsec = tv % TIMEGRAN;							// nanoseconds
} // Timespec

static inline int64_t nsecs( Duration dur ) with( dur ) { return tv; }

static inline Duration +?( Duration rhs ) with( rhs ) {	return (Duration)@{ +tv }; }
static inline Duration ?+?( Duration & lhs, Duration rhs ) { return (Duration)@{ lhs.tv + rhs.tv }; }
static inline Duration ?+=?( Duration & lhs, Duration rhs ) { lhs = lhs + rhs; return lhs; }

static inline Duration -?( Duration rhs ) with( rhs ) { return (Duration)@{ -tv }; }
static inline Duration ?-?( Duration & lhs, Duration rhs ) { return (Duration)@{ lhs.tv - rhs.tv }; }
static inline Duration ?-=?( Duration & lhs, Duration rhs ) { lhs = lhs - rhs; return lhs; }

static inline Duration ?*?( Duration lhs, int64_t rhs ) { return (Duration)@{ lhs.tv * rhs }; }
static inline Duration ?*?( int64_t lhs, Duration rhs ) { return (Duration)@{ lhs * rhs.tv }; }
static inline Duration ?*=?( Duration & lhs, int64_t rhs ) { lhs = lhs * rhs; return lhs; }

static inline Duration ?/?( Duration lhs, int64_t rhs ) { return (Duration)@{ lhs.tv / rhs }; }
static inline int64_t ?/?( Duration lhs, Duration rhs ) { return lhs.tv / rhs.tv; }
static inline Duration ?/=?( Duration & lhs, int64_t rhs ) { lhs = lhs / rhs; return lhs; }

static inline Duration ?%?( Duration lhs, int64_t rhs ) { return (Duration)@{ lhs.tv % rhs }; }
static inline int64_t ?%?( int64_t lhs, Duration rhs ) { return lhs % (rhs.tv / TIMEGRAN); }
static inline int64_t ?%?( Duration lhs, Duration rhs ) { return lhs.tv % rhs.tv; }

static inline _Bool ?==?( Duration lhs, Duration rhs ) { return lhs.tv == rhs.tv; }
static inline _Bool ?!=?( Duration lhs, Duration rhs ) { return lhs.tv != rhs.tv; }
static inline _Bool ?<?( Duration lhs, Duration rhs ) { return lhs.tv < rhs.tv; }
static inline _Bool ?<=?( Duration lhs, Duration rhs ) { return lhs.tv <= rhs.tv; }
static inline _Bool ?>?( Duration lhs, Duration rhs ) { return lhs.tv > rhs.tv; }
static inline _Bool ?>=?( Duration lhs, Duration rhs ) { return lhs.tv >= rhs.tv; }

static inline Duration abs( Duration lhs ) {
	return lhs.tv >= 0 ? lhs : -lhs;
} // abs

static inline forall( dtype ostype | ostream( ostype ) )
ostype & ?|?( ostype & os, Duration dur ) with( dur ) {
	os | tv / TIMEGRAN;
	char buf[16];
	snprintf( buf, 16, "%09ld", ((tv < 0 ? -tv : tv) % TIMEGRAN) );
	int i;
	for ( i = 8; i >= 0 && buf[i] == '0' ; i -= 1 );	// find least significant digit
	if ( i != -1 ) { buf[i + 1] = '\0';	os | '.' | buf; }
	return os;
}

static inline Duration ?`ns( int64_t nsec ) { return (Duration)@{ nsec }; }
static inline Duration ?`us( int64_t usec ) { return (Duration)@{ usec * (TIMEGRAN / 1_000l) }; }
static inline Duration ?`ms( int64_t msec ) { return (Duration)@{ msec * (TIMEGRAN / 1_000_000l) }; }
static inline Duration ?`s ( int64_t sec ) { return (Duration)@{ sec * TIMEGRAN }; }
static inline Duration ?`s ( double  sec ) { return (Duration)@{ sec * TIMEGRAN }; }
static inline Duration ?`m ( int64_t min ) { return (Duration)@{ min * (60L * TIMEGRAN) }; }
static inline Duration ?`m ( double  min ) { return (Duration)@{ min * (60L * TIMEGRAN) }; }
static inline Duration ?`h ( int64_t hours ) { return (Duration)@{ hours * (3600L * TIMEGRAN) }; }
static inline Duration ?`h ( double  hours ) { return (Duration)@{ hours * (3600L * TIMEGRAN) }; }
static inline Duration ?`d ( int64_t days ) { return (Duration)@{ days * (24L * 3600L * TIMEGRAN) }; }
static inline Duration ?`d ( double  days ) { return (Duration)@{ days * (24L * 3600L * TIMEGRAN) }; }
static inline Duration ?`w ( int64_t weeks ) { return (Duration)@{ weeks * (7L * 24L * 3600L * TIMEGRAN) }; }
static inline Duration ?`f ( int64_t fortnight ) { return (Duration)@{ fortnight * (14L * 24L * 3600L * TIMEGRAN) }; }

static inline int64_t ?`s ( Duration dur ) { return dur.tv / TIMEGRAN; }
static inline int64_t ?`m ( Duration dur ) { return dur.tv / (60L * TIMEGRAN); }
static inline int64_t ?`h ( Duration dur ) { return dur.tv / (3600L * TIMEGRAN); }
static inline int64_t ?`d ( Duration dur ) { return dur.tv / (24L * 3600L * TIMEGRAN); }
static inline int64_t ?`w ( Duration dur ) { return dur.tv / (7L * 24L * 3600L * TIMEGRAN); }
static inline int64_t ?`f ( Duration dur ) { return dur.tv / (14L * 24L * 3600L * TIMEGRAN); }


//######################### Time #########################


struct Time {
	uint64_t tv;
};

#ifdef __CFA_DEBUG__
#define CreateFmt "Attempt to create Time( year=%d, month=%d, day=%d, hour=%d, min=%d, sec=%d, nsec=%d ), " \
	"which exceeds range 00:00:00 UTC, January 1, 1970 to 03:14:07 UTC, January 19, 2038."
#endif // __CFA_DEBUG__

void mktime( Time & time, int year, int month, int day, int hour, int min, int sec, int nsec ) with( time ) {
	tm tm;

//	tzset();											// initialize time global variables
	tm.tm_isdst = -1;									// let mktime determine if alternate timezone is in effect
	tm.tm_year = year - 1900;							// mktime uses 1900 as its starting point
	tm.tm_mon = month - 1;
	tm.tm_mday = day;									// mktime uses range 1-31
	tm.tm_hour = hour;
	tm.tm_min = min;
	tm.tm_sec = sec;
	time_t epochsec = mktime( &tm );
#ifdef __CFA_DEBUG__
	if ( epochsec == (time_t)-1 ) {
		abort( CreateFmt, year, month, day, hour, min, sec, nsec );
	} // if
#endif // __CFA_DEBUG__
	tv = (int64_t)(epochsec) * TIMEGRAN + nsec;			// convert to nanoseconds
#ifdef __CFA_DEBUG__
	if ( tv > 2147483647LL * TIMEGRAN ) {				// between 00:00:00 UTC, January 1, 1970 and 03:14:07 UTC, January 19, 2038.
		abort( CreateFmt, year, month, day, hour, min, sec, nsec );
	} // if
#endif // __CFA_DEBUG__
} // mktime

static inline void ?{}( Time & t ) with( t ) {
	tv = 0;
} // Time

// These two constructors must not call mktime because it calls malloc. The malloc calls lead to recursion problems
// because Time values are created from the sigalrm handler in composing the next context switch event.

static inline void ?{}( Time & t, int sec ) with( t ) {
#ifdef __CFA_DEBUG__
	if ( tv < 0 || tv > 2147483647LL ) {				// between 00:00:00 UTC, January 1, 1970 and 03:14:07 UTC, January 19, 2038.
	    abort( CreateFmt, 1970, 0, 0, 0, 0, sec, 0 );
	} // if
#endif // __CFA_DEBUG__
	tv = (int64_t)sec * TIMEGRAN;
} // Time

static inline void ?{}( Time & t, int sec, int nsec ) with( t ) {
#ifdef __U_DEBUG__
	if ( tv < 0 || tv > 2147483647LL || nsec < 0 ) {	// between 00:00:00 UTC, January 1, 1970 and 03:14:07 UTC, January 19, 2038.
	    abort( CreateFmt, 1970, 0, 0, 0, 0, sec, nsec );
	} // if
#endif // __U_DEBUG__
	tv = (int64_t)sec * TIMEGRAN + nsec;
} // Time

static inline void ?{}( Time & time, int min, int sec, long int nsec ) {
	mktime( time, 1970, 1, 1, 0, min, sec, nsec );
} // Time

static inline void ?{}( Time & time, int hour, int min, int sec, long int nsec ) {
	mktime( time, 1970, 1, 1, hour, min, sec, nsec );
} // Time

static inline void ?{}( Time & time, int day, int hour, int min, int sec, long int nsec ) {
	mktime( time, 1970, 1, day, hour, min, sec, nsec );
} // Time

static inline void ?{}( Time & time, int month, int day, int hour, int min, int sec, long int nsec ) {
	mktime( time, 1970, month, day, hour, min, sec, nsec );
} // Time

static inline void ?{}( Time & time, int year, int month, int day, int hour, int min, int sec, long int nsec ) {
	mktime( time, year, month, day, hour, min, sec, nsec );
} // Time

static inline void ?{}( Time & time, timeval t ) with( time ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_usec * 1000;
} // Time

static inline void ?{}( Time & time, timespec t ) with( time ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_nsec;
} // Time

static inline Time ?=?( Time & time, timeval t ) with( time ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_usec * 1000;
	return time;
} // ?=?

static inline Time ?=?( Time & time, timespec t ) with( time ) {
	tv = (int64_t)t.tv_sec * TIMEGRAN + t.tv_nsec;
	return time;
} // ?=?

static inline void ?{}( timeval & t, Time time ) with( time ) {
	t.tv_sec = tv / TIMEGRAN;							// seconds
	t.tv_usec = tv % TIMEGRAN / ( TIMEGRAN / 1_000_000L ); // microseconds
} // ?{}

static inline void ?{}( timespec & t, Time time ) with( time ) {
	t.tv_sec = tv / TIMEGRAN;							// seconds
	t.tv_nsec = tv % TIMEGRAN;							// nanoseconds
} // ?{}

static inline int64_t nsec( Time time ) with( time ) { return tv; }

static inline Time ?+?( Time & lhs, Duration rhs ) { return (Time)@{ lhs.tv + rhs.tv }; }
static inline Time ?+?( Duration lhs, Time rhs ) { return rhs + lhs; }
static inline Time ?+=?( Time & lhs, Duration rhs ) { lhs = lhs + rhs; return lhs; }

static inline Duration ?-?( Time lhs, Time rhs ) { return (Duration)@{ lhs.tv - rhs.tv }; }
static inline Time ?-?( Time lhs, Duration rhs ) { return (Time)@{ lhs.tv - rhs.tv }; }
static inline Time ?-=?( Time & lhs, Duration rhs ) { lhs = lhs - rhs; return lhs; }
static inline _Bool ?==?( Time lhs, Time rhs ) { return lhs.tv == rhs.tv; }
static inline _Bool ?!=?( Time lhs, Time rhs ) { return lhs.tv != rhs.tv; }
static inline _Bool ?<?( Time lhs, Time rhs ) { return lhs.tv < rhs.tv; }
static inline _Bool ?<=?( Time lhs, Time rhs ) { return lhs.tv <= rhs.tv; }
static inline _Bool ?>?( Time lhs, Time rhs ) { return lhs.tv > rhs.tv; }
static inline _Bool ?>=?( Time lhs, Time rhs ) { return lhs.tv >= rhs.tv; }

static inline char * yymmd( Time time, char * buf ) with( time ) {
	tm tm;
	time_t s = tv / TIMEGRAN;
	gmtime_r( &s, &tm );
	snprintf( buf, 9, "%02d/%02d/%02d", tm.tm_year % 99, tm.tm_mon, tm.tm_mday );
	return buf;
} // yymmd

static inline char * mmyyd( Time time, char * buf ) with( time ) {
	tm tm;
	time_t s = tv / TIMEGRAN;
	gmtime_r( &s, &tm );
	snprintf( buf, 9, "%02d/%02d/%02d", tm.tm_mon, tm.tm_year % 99, tm.tm_mday );
	return buf;
} // yymmd

static inline char * dmmyy( Time time, char * buf ) with( time ) {
	tm tm;
	time_t s = tv / TIMEGRAN;
	gmtime_r( &s, &tm );
	snprintf( buf, 9, "%02d/%02d/%02d", tm.tm_mday, tm.tm_mon, tm.tm_year % 99 );
	return buf;
} // yymmd

static inline forall( dtype ostype | ostream( ostype ) )
ostype & ?|?( ostype & os, Time time ) with( time ) {
	char buf[32];										// at least 26
	time_t s = tv / TIMEGRAN;
	tm tm;
	gmtime_r( &s, &tm );								// ctime_r adjusts for timezone
	asctime_r( &tm, (char *)&buf );
	buf[24] = '\0';										// remove trailing '\n'
	long int ns = (tv < 0 ? -tv : tv) % TIMEGRAN;
	if ( ns == 0 ) {
		os | buf;
	} else {
		buf[19] = '\0';
		os | buf;
		char buf2[16];
		snprintf( buf2, 16, "%09ld", ns );
		int i;
		for ( i = 8; i >= 0 && buf2[i] == '0' ; i -= 1 ); // find least significant digit
		if ( i != -1 ) { buf2[i + 1] = '\0'; os | '.' | buf2; }
		os | ' ' | &buf[20];
	} // if
	return os;
} // ?|?

//######################### Clock #########################


struct Clock {
	Duration offset;									// for virtual clock: contains offset from real-time
	int clocktype;										// implementation only -1 (virtual), CLOCK_REALTIME
};

void resetClock( Clock & clk ) with( clk ) {
	clocktype = CLOCK_REALTIME;
} // Clock::resetClock

void resetClock( Clock & clk, Duration adj ) with( clk ) {
	clocktype = -1;
	Duration tz = (timeval){ timezone, 0 };
	offset = adj + tz;
} // resetClock

void ?{}( Clock & clk ) {
	resetClock( clk );
} // Clock

void ?{}( Clock & clk, Duration adj ) {
	resetClock( clk, adj );
} // Clock

Duration getRes() {
	struct timespec res;
	clock_getres( CLOCK_REALTIME, &res );
	return (Duration){ res };
} // getRes

Time getTime() {
	timespec curr;
	clock_gettime( CLOCK_REALTIME_COARSE, &curr );
	return (Time){ curr };
} // getTime

Time getTime( Clock & clk ) with( clk ) {
	return getTime() + offset;
} // getTime

Time ?()( Clock & clk ) with( clk ) {					// alternative syntax
	return getTime() + offset;
} // getTime

timeval getTime( Clock & clk ) {
	return (timeval){ clk() };
} // getTime

tm getTime( Clock & clk ) with( clk ) {
	tm ret;
	localtime_r( getTime( clk ).tv_sec, &ret );
	return ret;
} // getTime

// Local Variables: //
// mode: c //
// tab-width: 4 //
// End: //

