NAME
    iCal::Parser - Parse iCalendar files into a data structure

SYNOPSIS
      use iCal::Parser

      my $parser=iCal::Parser->new();
      my $hash=$parser->parse($file);

      $parser->parse($another_file);
      my $combined=$parser->calendar;

      my $combined=iCal::Parser->new->parse(@files);

DESCRIPTION
    This module processes iCalendar (vCalendar 2.0) files as specified in
    RFC 2445 into a data structure. It handles recurrences ("RRULE"s),
    exclusions ("EXDATE"s), event updates (events with a "RECURRENCE-ID"),
    and nested data structures ("ATTENDEES" and "VALARM"s). It currently
    ignores the "VTIMEZONE", "VJOURNAL" and "VFREEBUSY" entry types.

    The data structure returned is a hash like the following:

        {
          calendars=>[\%cal, ...],
          events=>{yyyy=>{mm=>{dd}=>{UID=>\%event}}
          todos=>[\%todo, ...]
        }

    That is, it contains an array of calendar hashes, a hash of events key
    by "year=>month=>day=>eventUID", and an array of todos.

    Calendars, events and todos are "rolled up" version os the hashes
    returned from Text::vFile::asData, with dates replaced by "DateTime"
    objects.

    During parsing, events in the input calendar are expanded out into
    multiple events, one per day covered by the event, as follows:

    *   If the event is a one day "all day" event (in ical, the event is
        24hrs long, starts at midnight on the day and ends a midnight of the
        next day), it contains no "hour" field and the "allday" field is set
        to 1.

    *   If the event is a recurrence ("RRULE"), one event per day is created
        as per the "RRULE" specification.

    *   If the event spans more than one day (the start and end dates are on
        different days, but does not contain an "RRULE"), it is expanded
        into multiple events, the first events end time is set to midnight,
        subsequent events are set to start at midnight and end at midnight
        the following day (same as an "allday" event, but the "allday" field
        is not set), and the last days event is set to run from midnight to
        the end time of the original multi-day event.

    *   If the event is an update (it contains a "RECURRENCE-ID"), the
        original event is updated. If the referenced event does not exist
        (e.g., it was deleted after the update), then the event is added as
        a new event.

    An example of each hash is below.

  Calendar Hash
        {
            'X-WR-CALNAME' => 'Test',
            'index' => 1,
            'X-WR-RELCALID' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
            'PRODID' => '-//Apple Computer\\, Inc//iCal 1.5//EN',
            'CALSCALE' => 'GREGORIAN',
            'X-WR-TIMEZONE' => 'America/New_York',
            'X-WR-CALDESC' => 'My Test Calendar',
            'VERSION' => '2.0'
        }

  Event Hash
    Note that "hours" and "allday" are mutually exclusive in the actual
    data. The "idref" field contains the "id" of the calendar the event came
    from, which is useful if the hash was created from multiple calendars.

        {
            'SUMMARY' => 'overnight',
            'hours' => '15.00',
            'allday' => 1,
            'UID' => '95CCBF98-3685-11D9-8CA5-000D93C45D90',
            'idref' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
            'DTSTAMP' => \%DateTime,
            'DTEND' => \%DateTime,
            'DTSTART' => \%DateTime
            'ATTENDEE' => [
               {
                  'CN' => 'Jay',
                  'value' => 'mailto:jayl@my.server'
               },
              ],
              'VALARM' => [
                {
                  'when' => \%DateTime,
                  'SUMMARY' => 'Alarm notification',
                  'ACTION' => 'EMAIL',
                  'DESCRIPTION' => 'This is an event reminder',
                  'ATTENDEE' => [
                     {
                       'value' => 'mailto:cpan@my.server'
                     }
                  ]
               }
             ],
        }

  Todo Hash
        {
            'URL' => 'mailto:me',
            'SUMMARY' => 'todo 1',
            'UID' => 'B78E68F2-35E7-11D9-9E64-000D93C45D90',
            'idref' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
            'STATUS' => 'COMPLETED',
            'COMPLETED' => \%DateTime,
            'DTSTAMP' => \%DateTime,
            'PRIORITY' => '9',
            'DTSTART' => \%DateTime,
            'DUE' => \%DateTime,
            'DESCRIPTION' => 'not much',
            'VALARM' => [
               {
                  'when' => \%DateTime,
                  'ATTACH' => 'file://localhost/my-file',
                  'ACTION' => 'PROCEDURE'
               }
            ],
        },

Methods
  new(%opt_args)
   Optional Arguments
    start {yyymmdd|DateTime}
        Only include events on or after "yyymmdd". Defaults to Jan of this
        year.

    end {yyyymmdd|DateTime}
        Only include events before "yyymmdd".

    no_events
        Don't include events in the output (todos only).

    no_todos
        Don't include todos in the output (events only).

    months n
        DateTime::Sets (used for calculating recurrences) are limited to
        approximately 200 entries. If an "end" date is not specified, the
        "to" date is set to the "start" date plus this many months. The
        default is 60.

    debug
        Set to non-zero for some debugging output during processing.

  parse([file|file_handle]+)
    Parse the input files or opened file handles and return the generated
    hash.

    This function can be called mutitple times and the calendars will be
    merge into the hash, each event tagged with the unique id of its
    calendar.

AUTHOR
    Rick Frankel, cpan@rickster.com

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

    The full text of the license can be found in the LICENSE file included
    with this module.

SEE ALSO
    Text::vFile::asData, DateTime::Set, DateTime::Span, iCal::Parser::SAX