#======================================================================

#                    L I B C O N V . P L 

#                    doc: Sat Dec  4 13:03:49 1999

#                    (c) 1999 A.M. Thurnherr

#======================================================================

# HISTORY:

#   Dec 12, 1999: - created for the Rainbow CM data as libdate

#   Jul 07, 2000: - renamed to libconv and added lat/lon conversions

#   Aug 21, 2000: - added &s2d()

#   Aug 24, 2000: - added &DDMMXh2d() and &DDDMMXh2d()

#   Aug 28, 2000: - moved &DDMMXh2d() and &DDDMMXh2d() to [libNODC.pl]

#   Sep 04, 2000: - added &GMT2d()

#   Sep 20, 2000: - added &fmtdate(), &fmttime()

#   Oct 16, 2000: - added &dmsh2d()

#   Oct 31, 2000: - added &T90(), &T68()

#   Jan 22, 2001: - BUG: &GMT2d() wrongly +ve-ized stuff like -00:05

#   Feb 28, 2001: - added &O2mlpl2umpkg()

#   Aug  3, 2001: - made &O2mlpl2umpkg() return NaN on -ve input

#   Aug  7, 2001: - added &O2umpkg2mlpl()

#                 - replaced temp_scale by ITS

#   Aug  8, 2001: - BUG: allowed for NaN O2 values

#   Aug 19, 2001: - change temp-conversions to allow nop; changed names

#   Sep  1, 2001: - BUG: allow for nan in addition to NaN

#	Dec 30, 2001: - generalized s2d()

#				  - BUG: allow NaNs on temp conversions

#	Feb  4, 2002: - allow for -ve O2 values in conversions to handle offsets

#	Aug 14, 2002: - moved ITS checks in ITS_68() & ITS_90()

#	Oct  9, 2002: - added &fmttime1(),&fmtdate1()

#	Jan 23, 2003: - added more time conversion routines

#	Apr 14, 2003: - removed antsReplaceParam() call

#	May 21, 2004: - added ``-'' as a valid date separator

#	Jun 22, 2004: - added HSV2RGB()

#	Jun 27, 2004: - renamed degree-conversion routines

#				  - added wraplon()

#	Dec  1, 2005: - cosmetics

#	Dec  9, 2005: - Version 3.2 [HISTORY]

#	Apr  4, 2006: - made epoch optional in &dayNo()

#	Apr 28, 2006: - added &dn2date()

#   Jul  1, 2006: - Version 3.3 [HISTORY]

#	Nov  9, 2006: - added dec_time()

#				  - added dn2date_time()

#				  - moved year forward in dn2date()

#	Oct 17, 2007: - dn2date -> Date

#				  - dn2date_time -> Time

#				  - adapted Date/Time to antsFunUsage() with default fields

#	Oct 19, 2007: - removed antsFunUsage() from non-UI funs

#	Nov 17, 2007: - added "." as another legal date separator

#	Jul 10, 2008: - added support for month names in dayNo()

#	Dec  1, 2008: - added dec_time_long()

#	Dec  3, 2008: - renamed many of the date-conversion routines

#				  - added frac_day()

#	Jan  8, 2009: - BUG: &Date() returned wrong date for any time after

#						 midnite on last day of a month

#	Oct 27, 2010: - added &day_secs()

#	Jan  3, 2010: - extended frac_day() to allow a single string time-spec

#	Jul 19, 2011: - made epoch aptional in mmddyy2dec_time()

#	Aug  2, 2011: - enhanced yymmdd2dec_time()

#	Apr 17, 2012: - added space as another date separator in ddmmyy2dec_time

#	May 22, 2012: - BUG: illegal time spec error was also produced on missing seconds

#				  - BUG: mmddyy2dec_time() did not allow for optional epoch argument

#	Aug  7, 2014: - finally cleaned up date conversions

#	Jan 27, 2017: - BUG: dayNo() numeric month could have leading/trailing whitespace

#	Jul  6, 2017: - BUG: date conversion routines did not parse 1/5/12 correctly

#	Dec 18, 2017: - removed ambiguous-date warning

#	May 22, 2018: - added NMEA2dec_time()

require "$ANTS/libEOS83.pl";                        # &sigma()

require "$ANTS/libPOSIX.pl";                        # &floor()

require "$ANTS/libstats.pl";                        # &min(),&max()

#----------------------------------------------------------------------

# Date Conversion

#----------------------------------------------------------------------

sub leapYearP(@)                                    # leap year?

{

    my($y) = @_;

    $y += ($y < 50) ? 2000 : 1900 if ($y < 100);    # Y2K

    return 0 if ($y%4 != 0);

    return 1 if ($y%100 != 0);

    return 0 if ($y%400 > 0);

    return 1;

}

sub monthLength(@)                                  # #days in given month/year

{

    my($y,$m) = @_;

    return 31 if ($m==1 || $m==3 || $m==5 || $m==7 ||

                  $m==8 || $m==10 || $m==12);

    return 30 if ($m==4 || $m==6 || $m==9 || $m==11);

    return 28 + &leapYearP($y) if ($m == 2);

    croak("$0: &monthLength(): Illegal month\n");

}

sub dayNo(@)										# day number, starting at 1

{

    my($y,$m,$d,$epoch) =

        &antsFunUsage(-3,"c..","year, month, day[, epoch]",@_);

	$epoch = $y unless defined($epoch);

	$m =~ s/\s//g;

	unless (cardinalp($m)) {

		$m = lc($m);

		if    ($m =~ /^jan/) { $m = 1; }

		elsif ($m =~ /^feb/) { $m = 2; }

		elsif ($m =~ /^mar/) { $m = 3; }

		elsif ($m =~ /^apr/) { $m = 4; }

		elsif ($m =~ /^may/) { $m = 5; }

		elsif ($m =~ /^jun/) { $m = 6; }

		elsif ($m =~ /^jul/) { $m = 7; }

		elsif ($m =~ /^aug/) { $m = 8; }

		elsif ($m =~ /^sep/) { $m = 9; }

		elsif ($m =~ /^oct/) { $m = 10; }

		elsif ($m =~ /^nov/) { $m = 11; }

		elsif ($m =~ /^dec/) { $m = 12; }

		else { croak("$0: unknown month $m\n"); }

	}

    my($dn) = 0;        

    $epoch += ($epoch < 50) ? 2000 : 1900           # Y2K       

        if ($epoch < 100);

    $y += ($y < 50) ? 2000 : 1900

        if ($y < 100);

    croak("$0: &dayNo(): Error: epoch > year\n")        # only positive times

        if ($y < $epoch);

    while ($epoch < $y) {                           # entire years

        $dn += 365 + &leapYearP($epoch);

        $epoch++;

    }

    croak("$0: &dayNo(): Error: day > #days of month\n")    # current month

        if ($d > &monthLength($y,$m));

    $dn += $d;

    $m--;

    while ($m > 0) {                                # current year

        $dn += &monthLength($y,$m);

        $m--;

    }

    return $dn

}

sub frac_day(@)										# fractional day

{

	my($h,$m,$s);

	if (@_ == 1) {

		($h,$m,$s) = split(':',$_[0]);

	} else {

		($h,$m,$s) = &antsFunUsage(3,'ccf',"<h:m:s>|<hour> <min> <sec>",@_);

	}

	croak("$0: &frac_day_long(): illegal time spec $h:$m:$s\n")

		unless ((defined($h) && $h>=0 && $h<24) &&

				(defined($m) && $m>=0 && $m<60) &&

				(!defined($s) || ($s>=0 && $s<60)));

	return $h/24 + $m/24/60 + $s/24/3600;

}

sub day_secs(@)										# seconds since daystart

{

	my($h,$m,$s) = &antsFunUsage(3,'ccf',"<hour> <min> <sec>",@_);

	croak("$0: &frac_day_long(): illegal time spec $h:$m:$s\n")

		unless ((defined($h) && $h>=0 && $h<24) &&

				(defined($m) && $m>=0 && $m<60) &&

				(!defined($s) || ($s>=0 && $s<60)));

	return $h*3600 + $m*60 + $s;

}

sub dec_time(@)										# decimal time

{

	my($epoch,$yy,$mm,$dd,$h,$m,$s) =

        &antsFunUsage(7,'ccccccf',"<epoch> <year> <month> <day> <hour> <min> <sec>",@_);

	return &dayNo($yy,$mm,$dd,$epoch) + &frac_day($h,$m,$s);

}

#----------------------------------------------------------------------

# String to Decimal Time Conversion

#----------------------------------------------------------------------

sub NMEA2dec_time(@)

{

	my($NMEA_string,$epoch) = &antsFunUsage(-1,'.','<NMEA string>[, epoch]',@_);

	# Mar 17 2018 01:23:09

	my($month,$day,$year,$time) = split(/\s+/,$NMEA_string);

	$epoch = $year unless defined($epoch);

	return dayNo($year,$month,$day,$epoch) + frac_day(split(':',$time));

}

{ my($date_fmt); 

	sub str2dec_time(@) 									# heuristic

	{

		my($ds,$ts,$epoch) =

			&antsFunUsage(-2,"..","date, hh:mm[:ss][, epoch]",@_);

		$ds =~ s/\s//g;

		$ts =~ s/\s//g;

		croak("$0 str2dec_time: date required\n") unless ($ds ne '');

		unless (defined($date_fmt)) {

			my($X,$Y,$Z) = split('[-/\.]',$ds);

			if ($X > 31) {									# YY/MM//DD

				$date_fmt = 1;							    

			} elsif ($X > 12) { 							# DD/MM/YY

				$date_fmt = 2;

			} elsif ($Y > 12) { 							# MM/DD/YY

				$date_fmt = 3;

			} else {

#				&antsInfo("str2dec_time: ambiguous date <$ds>; MM/DD/YY assumed");

				$date_fmt = 3;

	        }

	    }

	    if 	  ($date_fmt == 1) { return yymmdd2dec_time($ds,$ts,$epoch); }

	    elsif ($date_fmt == 2) { return ddmmyy2dec_time($ds,$ts,$epoch); }

	    else 				   { return mmddyy2dec_time($ds,$ts,$epoch); }

    }

}

sub mmddyy2dec_time(@)								

{

	my($ds,$ts,$epoch) =

        &antsFunUsage(-2,"..","MM/DD/[YY]YY, hh:mm[:ss][, epoch]",@_);

	my($time) = 0;

	if ($ds ne '') {

		my($yy,$mm,$dd);

		if (length($ds) == 6 && $ds =~ m{^\d+$}) {

			$mm = substr($ds,0,2);

			$dd = substr($ds,2,2);

			$yy = substr($ds,4,2);

		} else {

			($mm,$dd,$yy) = split('[-/\.]',$ds);

		}

		$time = dayNo($yy,$mm,$dd,$epoch);

	}

	if ($ts ne '') {

		my($h,$m,$s) = split(':',$ts);

		$s = 0 unless defined($s);

	    return $time + &frac_day($h,$m,$s);

	}

	return $time;

}

sub ddmmyy2dec_time(@)

{

	my($ds,$ts,$epoch) =

        &antsFunUsage(-2,"..","DD/MM/[YY]YY, hh:mm[:ss][, epoch]",@_);

	my($time) = 0;

	if ($ds ne '') {

		my($yy,$mm,$dd);

		if (length($ds) == 6 && $ds =~ m{^\d+$}) {

			$dd = substr($ds,0,2);

			$mm = substr($ds,2,2);

			$yy = substr($ds,4,2);

		} else {

			($dd,$mm,$yy) = split('[-/\.]',$ds);

		}

		$time = dayNo($yy,$mm,$dd,$epoch);

	}

	if ($ts ne '') {

		my($h,$m,$s) = split(':',$ts);

		$s = 0 unless defined($s);

	    return $time + &frac_day($h,$m,$s);

	}

	return $time;

}

sub yymmdd2dec_time(@)								

{

	my($ds,$ts,$epoch) =

        &antsFunUsage(-2,"..","[YY]YY/MM/DD, hh:mm[:ss][, epoch]",@_);

	my($time) = 0;

	if ($ds ne '') {								

		my($yy,$mm,$dd);

		if (length($ds) == 6 && $ds =~ m{^\d+$}) {

			$yy = substr($ds,0,2);

			$mm = substr($ds,2,2);

			$dd = substr($ds,4,2);

		} else {

			($yy,$mm,$dd) = split('[-/\.]',$ds);

		}

		$time = dayNo($yy,$mm,$dd,$epoch);

	}

	if ($ts ne '') {

		my($h,$m,$s) = split(':',$ts);

		$s = 0 unless defined($s);

	    return $time + &frac_day($h,$m,$s);

	}

	return $time;

}

#----------------------------------------------------------------------

#----------------------------------------------------------------------

{ my(@fc);

	sub Date(@) 										# day number -> date

	{

		my($dnf);										# find std dn field & epoch

		if (@_ == 0) {

			for (my($i)=0; $i<@antsLayout; $i++) {

				next unless ($antsLayout[$i] =~ /^dn(\d\d)$/);

				$dnf = $antsLayout[$i]; push(@_,$1);

				last;

	        }

	    }

		my($year,$day) = &antsFunUsage(2,"cf","epoch, dayNo",\@fc,undef,$dnf,@_);

		$year += ($year < 50) ? 2000 : 1900 			# Y2K

			if ($year < 100);

		$day = int($day);								# prevent runover on last day of month

		while ($day > 365+&leapYearP($year)) {			# adjust year

			$day -= 365 + &leapYearP($year);

			$year++;

		}

		my($month) = 1;

		while ($day > &monthLength($year,$month)) {

			$day -= &monthLength($year,$month);

			$month++;

		}

		return sprintf('%04d/%02d/%02d',$year,$month,$day);

	}

}

{ my(@fc);

	sub Time(@) 										# day number -> date/time

	{

		my($dnf);										# find standard dn field

		for (my($i)=0; $i<@antsLayout; $i++) {

			next unless ($antsLayout[$i] =~ /^dn\d\d$/);

			$dnf = $antsLayout[$i];

			last;

		}

		my($fday) = &antsFunUsage(1,"f","dayNo",\@fc,$dnf,@_);

		my($day) = int($fday);

		$fday -= $day;

		my($hour) = int(24*$fday);

		$fday -= $hour/24;

		my($min) = int(24*60*$fday);

		$fday -= $min/24/60;

		my($sec) = round(24*3600*$fday);

		$min++,$sec=0 if ($sec == 60);

		$hour++,$min=0 if ($min == 60);

		$day++,$hour=0 if ($hour == 24);

		return sprintf('%02d:%02d:%02d',$hour,$min,$sec);

	}

}

#----------------------------------------------------------------------

# Other Misc Date Conversions

#----------------------------------------------------------------------

sub date2str(@)

{

    my($MM,$DD,$YYYY) = &antsFunUsage(3,'ccc','month, day, year',@_);

    $YYYY += 2000 if ($YYYY < 50);

    $YYYY += 1900 if ($YYYY < 100);

    return sprintf('%02d',$MM) . '/' .

           sprintf('%02d',$DD) . '/' . $YYYY;

}

sub card_date2str(@)

{

    my($DDMMYY) = &antsFunUsage(1,'c','ddmmyy',@_);

    $DDMMYY = sprintf('%06d',$DDMMYY);

    return &fmtdate(substr($DDMMYY,2,2),substr($DDMMYY,0,2),substr($DDMMYY,4,2));

}

sub time2str(@)

{

    my($HH,$MM) = &antsFunUsage(2,'cc','hr, min',@_);

    return sprintf('%02d',$HH) . ':' . sprintf('%02d',$MM);

}

sub card_time2str(@)

{

    my($HHMM) = &antsFunUsage(1,'c','hrmin',@_);

    return &fmttime(int($HHMM/100),$HHMM%100);

}

#----------------------------------------------------------------------

# Lat/Lon Conversion

#----------------------------------------------------------------------

sub wraplon(@)		# get sign of longitudes right

{

	my($deg) = &antsFunUsage(1,'f','deg',@_);

	return ($deg > 180) ? $deg - 360 : $deg;

}

sub dmh2deg(@)		# dd mm.m NSEW -> dd.d

{

    my($deg,$min,$hemisph) =

        &antsFunUsage(3,'ff1','deg, min, hemisphere',@_);

    croak("$0 dmh2d(): <deg> may not be -ve\n") if ($deg < 0);

    croak("$0 dmh2d(): <min> may not be -ve\n") if ($min < 0);

    $deg += $min/60;

    $_ = $hemisph;

    SWITCH: {

        $deg = -$deg, last SWITCH if (/[sSwW]/);

        last SWITCH if (/[nNeE]/);

        croak("$0 dmh2d(): $hemisph is an invalid hemisphere id\n");

    }

    return $deg;

}

sub dmsh2deg(@)   # dd mm ss NSEW -> dd.d

{

    my($deg,$min,$sec,$hemisph) =

        &antsFunUsage(4,'fff1','deg, min, sec, hemisphere',@_);

    croak("$0 dmsh2d(): <deg> may not be -ve\n") if ($deg < 0);

    croak("$0 dmsh2d(): <min> may not be -ve\n") if ($min < 0);

    croak("$0 dmsh2d(): <sec> may not be -ve\n") if ($sec < 0);

    $deg += $min/60 + $sec/3600;

    $_ = $hemisph;

    SWITCH: {

        $deg = -$deg, last SWITCH if (/[sSwW]/);

        last SWITCH if (/[nNeE]/);

        croak("$0 dmh2d(): $hemisph is an invalid hemisphere id\n");

    }

    return $deg;

}

sub str2deg(@)      # string containing dd [mm.m] [NSEW] -> dd.d

{

    my($s) = &antsFunUsage(1,'.',"'deg[ :][min][ ]hemisphere'",@_);

    my($deg,$a,$b) = ($s =~ m{^([-\d]+)[\s:]([\d\.]+)\s*([NSEW])$});

#    print(STDERR "--> $deg, $a, $b\n");

	return ($b eq "") ? &dmh2d($deg,0,$a) : &dmh2d($deg,$a,$b);