package Time::Seconds;
use strict;
use vars qw/@EXPORT @EXPORT_OK @ISA/;

@ISA = 'Exporter';

@EXPORT = qw(
ONE_MINUTE
ONE_HOUR
ONE_DAY
ONE_WEEK
ONE_MONTH
ONE_REAL_MONTH
ONE_YEAR
ONE_REAL_YEAR
ONE_FINANCIAL_MONTH
LEAP_YEAR
NON_LEAP_YEAR
);

@EXPORT_OK = qw(cs_sec cs_mon);

use constant ONE_MINUTE => 60;
use constant ONE_HOUR => 3_600;
use constant ONE_DAY => 86_400;
use constant ONE_WEEK => 604_800;
use constant ONE_MONTH => 2_629_744; # ONE_YEAR / 12
use constant ONE_REAL_MONTH => '1M';
use constant ONE_YEAR => 31_556_930; # 365.24225 days
use constant ONE_REAL_YEAR => '1Y';
use constant ONE_FINANCIAL_MONTH => 2_592_000; # 30 days
use constant LEAP_YEAR => 31_622_400; # 366 * ONE_DAY
use constant NON_LEAP_YEAR => 31_536_000; # 365 * ONE_DAY

# hacks to make Time::Piece compile once again
use constant cs_sec => 0;
use constant cs_mon => 1;

use overload
'fallback' => 'undef',
'0+' => \&seconds,
'""' => \&seconds,
'<=>' => \&compare,
'+' => \&add,
'-' => \&subtract,
'-=' => \&subtract_from,
'+=' => \&add_to,
'=' => \&copy;

sub new {
my $class = shift;
my ($val) = @_;
$val = 0 unless defined $val;
bless \$val, $class;
}

sub _get_ovlvals {
my ($lhs, $rhs, $reverse) = @_;
$lhs = $lhs->seconds;

if (UNIVERSAL::isa($rhs, 'Time::Seconds')) {
$rhs = $rhs->seconds;
}
elsif (ref($rhs)) {
die "Can't use non Seconds object in operator overload";
}

if ($reverse) {
return $rhs, $lhs;
}

return $lhs, $rhs;
}

sub compare {
my ($lhs, $rhs) = _get_ovlvals(@_);
return $lhs <=> $rhs;
}

sub add {
my ($lhs, $rhs) = _get_ovlvals(@_);
return Time::Seconds->new($lhs + $rhs);
}

sub add_to {
my $lhs = shift;
my $rhs = shift;
$rhs = $rhs->seconds if UNIVERSAL::isa($rhs, 'Time::Seconds');
$$lhs += $rhs;
return $lhs;
}

sub subtract {
my ($lhs, $rhs) = _get_ovlvals(@_);
return Time::Seconds->new($lhs - $rhs);
}

sub subtract_from {
my $lhs = shift;
my $rhs = shift;
$rhs = $rhs->seconds if UNIVERSAL::isa($rhs, 'Time::Seconds');
$$lhs -= $rhs;
return $lhs;
}

sub copy {
Time::Seconds->new(${$_[0]});
}

sub seconds {
my $s = shift;
return $$s;
}

sub minutes {
my $s = shift;
return $$s / 60;
}

sub hours {
my $s = shift;
$s->minutes / 60;
}

sub days {
my $s = shift;
$s->hours / 24;
}

sub weeks {
my $s = shift;
$s->days / 7;
}

sub months {
my $s = shift;
$s->days / 30.4368541;
}

sub financial_months {
my $s = shift;
$s->days / 30;
}

sub years {
my $s = shift;
$s->days / 365.24225;
}

sub pretty {
my $s = shift;
my $str = "";
if ($s < 0) {
$s = -$s;
$str = "minus ";
}
if ($s >= ONE_MINUTE) {
if ($s >= ONE_HOUR) {
if ($s >= ONE_DAY) {
my $days = sprintf("%d", $s->days); # does a "floor"
$str = $days . " days, ";
$s -= ($days * ONE_DAY);
}
my $hours = sprintf("%d", $s->hours);
$str .= $hours . " hours, ";
$s -= ($hours * ONE_HOUR);
}
my $mins = sprintf("%d", $s->minutes);
$str .= $mins . " minutes, ";
$s -= ($mins * ONE_MINUTE);
}
$str .= $s->seconds . " seconds";
return $str;
}

1;
__END__

=head1 NAME

Time::Seconds - a simple API to convert seconds to other date values

=head1 SYNOPSIS

use Time::Piece;
use Time::Seconds;

my $t = localtime;
$t += ONE_DAY;

my $t2 = localtime;
my $s = $t - $t2;

print "Difference is: ", $s->days, "\n";

=head1 DESCRIPTION

This module is part of the Time::Piece distribution. It allows the user
to find out the number of minutes, hours, days, weeks or years in a given
number of seconds. It is returned by Time::Piece when you delta two
Time::Piece objects.

Time::Seconds also exports the following constants:

ONE_DAY
ONE_WEEK
ONE_HOUR
ONE_MINUTE
ONE_MONTH
ONE_YEAR
ONE_FINANCIAL_MONTH
LEAP_YEAR
NON_LEAP_YEAR

Since perl does not (yet?) support constant objects, these constants are in
seconds only, so you cannot, for example, do this: C<print ONE_WEEK-E<gt>minutes;>

=head1 METHODS

The following methods are available:

my $val = Time::Seconds->new(SECONDS)
$val->seconds;
$val->minutes;
$val->hours;
$val->days;
$val->weeks;
$val->months;
$val->financial_months; # 30 days
$val->years;
$val->pretty; # gives English representation of the delta

The usual arithmetic (+,-,+=,-=) is also available on the objects.

The methods make the assumption that there are 24 hours in a day, 7 days in
a week, 365.24225 days in a year and 12 months in a year.
(from The Calendar FAQ at http://www.tondering.dk/claus/calendar.html)

=head1 AUTHOR

Matt Sergeant, [email protected]

Tobias Brox, [email protected]

Bal�zs Szab� (dLux), [email protected]

=head1 LICENSE

Please see Time::Piece for the license.

=head1 Bugs

Currently the methods aren't as efficient as they could be, for reasons of
clarity. This is probably a bad idea.

=cut