NAME
    Date::Handler - Easy Date Object

SYNOPSIS
      use Date::Handler;
 
      my $date = new Date::Handler({ date => time, time_zone => 'Europe/Paris', });
      my $date = new Date::Handler({ date => [2001,04,12,03,01,55], time_zone => 'EST', });
      my $date = new Date::Handler({ date => {
                                                    year => 2001,
                                                    month => 4,
                                                    day => 12,
                                                    hour => 3,
                                                    min => 1,
                                                    sec => 55,
                                            }, time_zone => 'America/Montreal', });

       print $date;
       print "$date";
       print $date->AllInfo();

       $date->new()                         Constructor
       $date->Year()                        2001
       $date->Month()                       1..12
       $date->Day()                         1..31
       $date->Hour()                        0..23
       $date->Min()                         0..59
       $date->Sec()                         0..59
       $date->Epoch($epoch)                 Seconds since epoch (GMT)
       $date->TimeZone()                    America/Montreal
       $date->TimeZoneName()                EST
       $date->LocalTime()                   localtime of the object's epoch 
       $date->TimeFormat($format_string)    strftime
       $date->GmtTime()                     gmtime of object's epoch
       $date->UtcTime()                     same as GmtTime()
       $date->GmtOffset()                   Offset of object's TZ in seconds
       $date->MonthName()                   April
       $date->WeekDay()                     1..7 (1 monday)
       $date->WeekDayName()                 Wednesday
       $date->FirstWeekDayOfMonth()         1..7
       $date->WeekOfMonth()                 1..4
       $date->DaysInMonth()                 31,30,29,28 depending on month and year.
       $date->IsLeapYear()                  1 if true, 0 if false
       $date->DayLightSavings()             1 if true, 0 if false
       $date->DayOfYear()                   Return the day of the year
       $date->DaysInYear()                  Returns the number of days in the year.
       $date->DaysLeftInYear()              Returns the number of days remaining in the year
       $date->Array2Epoch([])                       Transfer [y,m,d,h,mm,ss] to epoch time
       $date->AsScalar ()                   Same as TimeFormat("%A, %B%e %Y %R (%Z)") 
       $date->AsNumber()                    same as Epoch()
       $date->AsArray()                     Returns [y,m,d,h,mm,ss]
       $date->AsHash()                      Returns { year => y, month => m, day => d, hour => h, min => mm, sec => ss }
       $date->AllInfo()                     Returns a string containing all of the Object's related information.
   
       my $delta = new Date::Handler::Delta([3,1,10,2,5,5]);
       my $delta = new Date::Handler::Delta({
                                                    years => 3,
                                                    months => 1,
                                                    days => 10,
                                                    hours => 2,
                                                    minutes => 5,
                                                    seconds => 5,
                                            });

       $delta->new                          (More information in perldoc Date::Handler::Delta)
       $delta->Months()                     Number of months in delta
       $delta->Seconds()                    Number of seconds in delta
       $delta->AsScalar()                   "%d months and %d seconds"
       $delta->AsNumber()                   "%d-%d-%d"
       $delta->AsArray()                    [y,m,ss]
       $delta->AsHash()                     { months => m, seconds => ss }

       $date + $delta = Date::Handler
       $date - $delta = Date::Handler
       $date - $date2 = Date::Handler::Delta
       $date + n = (+n seconds)
       $date - n = (-n seconds)

       $delta + $delta = Date::Handler::Delta
       $delta - $delta = Date::Handler::Delta
       $delta * n = Date::Handler::Delta
       $delta / n = Date::Handler::Delta
       $delta + n = (+n seconds)
       $delta - n = (-n seconds)

       my $range = Date::Handler::Range->new({
                                                    date => $date,
                                                    delta => $delta,
                                            });
       my $range = Date::Handler::Range->new({
                                                    date => [2001,06,08,2,00,00],
                                                    delta => [0,0,1,0,0],
                                            });

       $range->new                  (More info in perldoc Date::Handler::Range)
       $range->Direction()          Specifies the direction of a range ('FORWARDS' || 'BACKWARDS')
       $range->StartDate()          Start Date::Handler object for this range and direction
       $range->EndDate()            End Date::Handler object for this range and direction
       $range->Overlaps($range2)    Returns true if range overlaps range2. undef otherwise.

DESCRIPTION
    Date::Handler is a container for dates that holds all the methods to
    transform itself from Timezone to Timezone and format itself. This
    module idea comes from an original version written by dLux (Szab,
    Balzs) <dlux@kapu.hu> in his module Class::Date.

    Date::Handler is implemented in pure Perl using POSIX modules, it
    encapsulates the environnement variable TZ for it's time zone management
    so you don't have to play with it externally in the implementation.

    It uses operator overloading and Delta date objects to calculates time
    differences.

    This code is still in it's alpha stage(v0.05) and should not be used on
    production systems without reviewing the actual test cases provided with
    this module in the Date::Handler::Test package.

IMPLEMENTATION
    Using the Date::Handler is simple.

  Creating the absolute Date::Handler

    The new() constructor receives only one argument as a hashref:

            my $date = new Date::Handler({
                                    date => time,
                                    time_zone => 'Asia/Hong_Kong',
                            });

    The 'date' key of this argument can be either:

    * Epoch time
    * Anonymous array of the form: [y,m,d,h,mm,ss]
    * A hashref of the form : { year => y,month => m, day => d, hour => h,
    min => mm, sec => ss }
    The items in the array (or hash) of the 'date' key should follow these
    rules:

    * year - The year number
    * mon - The number of months since January, in the range 1 to 12.
    * day - The day of the month, in the range 1 to 31.
    * hour - The number of hours past midnight, in the range 0 to 23.
    * min - The number of minutes after the hour, in the range 0 to 59.
    * sec - The number of seconds after the minute, normally in the range 0
    to 59.
    The 'time_zone' key represents the time zone name this date is
    considered in. i.e. Africa/Dakar, EST, PST, EDT

  Accessors

    You can access the data inside the object using any of the provided
    methods. These methods are detailed in the SYNOPSIS up above.

  Modifying the object

    A created Date::Handler can be modified on the fly by many ways:

    * Changing the time_zone of the object using TimeZone()
    * Changing the internal date of the object using Epoch()
    * By using operators in combination with Date::Handler::Delta objects
    Example:

            my $date = new Date::Handler({ date => time });
            $date->TimeZone('Asia/Tokyo');
            print "Time in tokyo: ".$date->LocalTime()."\n";
            $date->Epoch(time);
            $date->TimeZone('America/Montreal');
            print "Time in Montreal: ".$date->LocalTime()."\n";
            $date->TimeZone('GMT');
            print "Greenwich Mean Time: ".$date->LocalTime()."\n";

  Using Date::Handler::Delta objects

    To go forward or backward in time with a date object, you can use the
    Date::Handler::Delta objects. These objects represent a time lapse
    represented in months and seconds. Since Date::Handler uses operator
    overloading, you can 'apply' a Delta object on an absolute date simply
    by using '+' and '-'.

    Example:

            #A Delta of 1 year.
            my $delta = new Date::Handler::Delta([1,0,0,0,0,0]);

            my $date = new Date::Handler({ date => time } );

            #$newdate is now one year in the furure.
            my $newdate = $date+$delta;
        
    Refer to the Date::Handler::Delta(1) documentation for more on Deltas.

  Using Date::Handler::Range objects

    Range objects are used to specify moments in time between 2 dates. For
    the moment, this functionnality is very primitive but will evolve in
    future versions. Each range object is constructed by a base
    Date::Handler object. Then combined to that is a Date::Handler::Delta
    will specify the length of the range. Then thirdly, the range is given a
    direction, either 'FORWARDS' or 'BACKWARDS' in time. From these three
    values are calculated a start date and an end date.

    Example:

            #Creation of the range starting now, ending in 2 days.
            my $range = Date::Handler::Range->new({
                                                            date => time(),
                                                            delta => [0,0,2,0,0],
                                                    });

            #This is already set to 'FORWARDS' by default.
            $range->Direction('FORWARDS');

            print "This range start ".$range->StartDate()." and ends ". $range->EndDate()."\n";

            #Another range, starting at the end date of range 1, going backwards in time 7 days.
            my $range2 = Date::Handler::Range->new({
                                                            date => $range->StartDate(),
                                                            delta => [0,0,7,0,0],
                                                    });
            $range2->Direction('BACKWARDS');

            #This returns true if range overlaps range2.
            $range->Overlaps($range2);

    As I said earlier, the range functionnality is still very primitive, and
    the interface might change.

  Operator overload special cases

    The Date::Handler overloaded operator have special cases. Refer to the
    SYNOPSIS to get a description of each overloaded operator's behaviour.

    One special case of the overload is when adding an integer 'n' to a
    Date::Handler's reference. This is treated as if 'n' was in seconds.
    Same thing for substraction.

    Example Uses of the overload:

            my $date = new Date::Handler({ date =>
                                            {
                                                    year => 2001,
                                                    month => 5,
                                                    day => 14,
                                                    hour => 5,
                                                    min => 0,
                                                    sec => 0,
                                            }});
            #Quoted string overload 
            print "Current date is $date\n";
        
            my $delta = new Date::Handler::Delta({ days => 5, });
        
            #'+' overload, now, $date is 5 days in the future.      
            $date += $delta;

            #Small clock. Not too accurate, but still ;)
            while(1)
            {
                    #Add one second to the date. (same as $date + 1)
                    $date++;
                    print "$date\n";
                    sleep(1);
            }

INHERITANCE
    A useful way of using Date::Handler in your code is to implement that a
    class that ISA Date::Handler. This way you can overload methods through
    the inheritance tree and change the object's behaviour to your needs.

    Here is a small example of an overloaded class that specifies a default
    timezone different than the machine's timezone.

            #!/usr/bin/perl
            package My::Date::Handler;
        
            use strict;
            use vars qw(@ISA $VERSION);
        
            use Date::Handler;
            @ISA = qw(Date::Handler);
        
            use constant DEFAULT_TIMEZONE => 'Europe/Moscow';
        
            sub TimeZone
            {
                    my ($self) = @_;
        
                    my $time_zone = $self->SUPER::TimeZone(@_);
        
                    return $time_zoneif defined $time_zone;
        
                    return $self->DEFAULT_TIMEZONE();
            }       
        
            1;
            __END__
                
BUGS (known)
    Dates after 2038 are not handled by this module yet. (POSIX)

    Dates before 1970 are not handled by this module. (POSIX)

    If you find bugs with this module, do not hesitate to contact the
    author. Your comments and rants are welcomed :)

CVS AND BLEEDING VERSIONS
    The latest developments and changes history for this module are
    available through cvsweb at:

    http://cvs.flatlineconstruct.com/

    The bleeding edge code is also available through anonymous CVS access
    via:

    cvs -d:pserver:anoncvs@cvs.flatlineconstruct.com:/home/cvs/anon checkout
    Date-Handler

TODO
    Add support for dynamic locale using perllocales functions. This will
    plugin directly with the use of strftime in the Date::Handler and
    provide locales.

    Add a list of supported timezones in the Constants class.Just didnt
    around to do it yet :) Feel free :) If you have patches, recommendations
    or suggestions on this module, please come forward :)

COPYRIGHT
    Copyright(c) 2001 Benoit Beausejour <bbeausej@pobox.com>

    All rights reserved. This program is free software; you can redistribute
    it and/or modify it under the same terms as Perl itself.

    Portions Copyright (c) Philippe M. Chiasson <gozer@cpan.org>

    Portions Copyright (c) Szab, Balzs <dlux@kapu.hu>

    Portions Copyright (c) Larry Rosler

AUTHOR
    Benoit Beausejour <bbeausej@pobox.com>

SEE ALSO
    Class::Date(1). Time::Object(1). Date::Calc(1). perl(1).

