#!/usr/bin/perl -w # rem2ics -- convert the output of "remind -s" into RFC2445 iCalendar format. # Copyright 2007,2008,2009 # Mark Atwood # Paul Hinze # Michael Schultz # # This program is free software; you can redistribute it and/or # modify it under the terms of the GNU General Public License # as published by the Free Software Foundation; either version 2 # of the License, or (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the # Free Software Foundation, Inc. # 51 Franklin Street, Fifth Floor # Boston MA 02110-1301 USA use strict; use warnings; =head1 NAME rem2ics - convert the output of "remind -s" into RFC2445 iCalendar format. =head1 SYNOPSIS TZ=I B [B<-man>] [B<-do>] [B<-norecur>] [B<-usetag>] Einput Eoutput =head1 OPTIONS AND ARGUMENTS =over 8 =item B<-man> Print the manual page and exit. =item B<-do> Actually do the conversion. Otherwise just print a brief help message and usage example, and then exit. =item B<-norecur> Do not attempt to detect and fold together recurring events. =item B<-usetag> Generate UIDs using remind TAG clauses. =back Input is from standard input Output is to standard output. =head1 USAGE remind -s360 -irem2ics=1 ~/.reminders 1 Jan 1991 | TZ=PST8PDT rem2ics -do >reminders.ics This tells B to use ~/.reminders, and to process the entire range of dates it can handle (from Jan 1 1991 to Dec 31 2020), and to define a variable named C, which can be used in C / C pairs. B will use a timezone of PST8PDT, and will fold events that have the same name and duration into a single iCalendar VEVENT object. =head1 NOTES =head2 Timezones and the TZ environment variable. B uses the TZ environment variable to determine the value of the RFC2445 TZID property. If you are running on a Linux or other GNU libc based system, you probably don't (and probably shouldn't) normally have TZ set. You can confirm this by running C at a shell prompt. If your remind data is in your "local time", and it probably is, you should probably set TZ to a good name for your local timezone just for the run of this script. You probably should NOT set TZ in your login scripts. You can use TZ like this: remind -s ~/.reminders | TZ=PST8PDT rem2ics -do >reminders.ics or remind -s ~/.reminders | TZ=US/Pacific rem2ics -do >reminders.ics If, for some reason, your remind files are all in GMT instead of localtime (you smart person you!), you can do this: remind -s ~/.reminders | TZ=GMT rem2ics -do >reminders.ics or remind -s ~/.reminders | TZ=0 rem2ics -do >reminders.ics and B will use the ISO8601 "Z" notation for GMT time in the ics file. (Other synonyms for GMT are the empty string (not the same as the TZ not set), "I<0>", "I", "I", "I", "I", "I, and "I".) If you leave TZ undefined and unset, B will use the ISO8601 "T" notation date strings with no TZID property, which RFC2445 calls a "floating time". Who knows, it might work for you! The TZ string value is literally incorporated into the iCalendar stream, so whatever your iCalendar-using application needs is what you should use. You may have to experiment a bit. You can look around in C to get the names of every timezone anywhere. This is the "Olson database" that RFC2445 refers to. Read the man page for L for more than you ever wanted to know about the format of these files, and about GNU libc's handling of timezones. As complex as it is, it's certainly better than what POSIX defines or what most legacy UNIX systems do, and most certainly better than Microsoft, who in their "cutting edge" "state of the art" "server" OS, still hasn't figured out that daylight time rules might be different in different years. If you just ran B without reading all this stuff, or if you don't want to worry about it at all, and somehow your iCalendar application manager is able to guess the proper timezone for you, just leave TZ undefined, and B will use the ISO8601 "T" notation date strings with no TZID property, which RFC2445 calls a "floating time". Who knows, it might work for you! =head2 Detecting recurring events B tries to detect recurring events. If any multiple events appear with exactly the text and exactly the same duration (including "no duration"), instead of multiple VEVENT objects, there will be just one VEVENT object, that will have a RFC2445 C property. B is not yet smart enough to derive an C based recurrence. If you really want that feature, either implement it and send in a patch, or contact the author and convince him to do it. =head2 Other iCalendar Properties B does not generate C or C. One would have to heuristically parse them out of the text, and everyone uses a idiosyncratic way of putting things in B. If the B<-usetag> option is not used or no C is set for a reminder, B will synthesize C properties for each VEVENT, but the UIDs will be different (and unique) for each run of B. If you run rem2ics twice and import the two resulting ICS streams into your new scheduling program, your appointments will appear twice. If, however, you have set C clauses in your reminders and activated B<-usetag>, these will be used. The same applies for tags synthesized by B's B<-y> option. Hence, it is more useful to use the B<-y> option than to let B synthesize UIDs, because the UIDs will stay the same across multiple runs. =head2 Other iCalendar Perl objects Why doesn't B use any of the iCalendar Perl stuff in CPAN? Because I don't trust them, and they are too big for this app. One links to a binary library. Another hasn't been maintained since 1991, and is full of notes as to how buggy and incomplete it is. And so forth. I am not at this moment interested in groveling around in L, L, L, L, or C. =head2 Previous implementation There is a working quick & dirty rem2ics written in awk by Anthony J. Chivetta Eachivetta@gmail.comE. But it has the following problems: it doesn't escape the text, it doesn't handle events that cross over midnight, it doesn't do timezones, it doesn't enforce the correct EOL sequence, and it doesn't fold long lines. This is a replacement for that script. =head1 TODO If TZ not set, grab out of system config somewhere Detect recurring events. If I'm REALLY smart, derive RRULE Handle characters not in US-ASCII. Latin1? UTF8? =head1 VERSION HISTORY =over 8 =item version 0.1 2007-02-08 First cut. =item version 0.2 2007-02-09 Reorg into multipass over a data structure. =item version 0.3 2007-02-10 Collapse repeating events. Fold output lines. =item version 0.9 2007-02-11 POD. Command line options. First public release. =item version 0.91 2007-02-14 Bug fix, error message for non-recurring events =item version 0.92 2008-01-28 Bug fix, rem2ics 0.91 chokes on timed reminders with duration using `remind -s` as it functions in remind-03.01.03. Remind 3.01 changed how the -s data is formatted for events that have a duration Patch by Paul Hinze Epaul dot t dot hinze at gmail dot comE and Michael Schultz Emjschultz at gmail dot comE =item version 0.93 2009-06-25 Add B<-usetag> option to allow for UIDs to stay the same across multiple runs by using the remind TAG clause. Patch by Tim Weber Escy at scytale dot nameE =back =head1 SEE ALSO L L L L L =head1 AUTHOR Copyright 2007,2008,2009 by Mark Atwood Eme+rem2ics@mark.atwood.nameE. L. Please report bugs (with patches, if possible). Inspired by Anthony J. Chivetta Eachivetta@gmail.comE's rem2ics in awk. Thank you to Dianne Skoll Edianne@skoll.ca for Remind, and to the IETF calsch wg for the iCalendar specification. =cut use Getopt::Long; use Pod::Usage; my $app_name = "rem2ics"; my $app_version = "0.93"; # process the command line my %options; GetOptions(\%options, qw(man do norecurr usetag)) || pod2usage(2); pod2usage(-verbose => 2) if ($options{man}); unless ($options{do}) { print STDERR "Run \"$0 -man\" for information and usage examples.\n" . "Pay special attention to information about timezone.\n"; exit(99); } # grab the hostname # this is used as part of the UID property of each VEVENT my $ical_uid_hostname = $ENV{'HOSTNAME'}; unless ($ical_uid_hostname) { print STDERR "Warning! " . "The environment variable HOSTNAME was not properly set.\n" . "Will use \"localhost\" in the RFC2445 UID property\n"; $ical_uid_hostname = "localhost"; } # look for the TZ my $ical_tzid = undef; if (exists $ENV{'TZ'}) { $ical_tzid = $ENV{'TZ'}; my %synonyms_for_gmt = ( '' => 1, '0' => 1, 'z' => 1, 'zulu' => 1, 'greenwitch' => 1, 'gmt' => 1, 'gmt+0' => 1, 'gmt-0' => 1, ); if (exists $synonyms_for_gmt{lc($ical_tzid)}) { $ical_tzid = ''; # empty means GMT, below } } else { # leave it undefined, that has a meaning below } # RFC2445 DTSTAMP property will be the time we started running ($^T) my ($ical_dtstamp); { my @gt = gmtime($^T); $ical_dtstamp = sprintf("%04d%02d%02dZ%02d%02d%02dZ", 1900+$gt[5], $gt[4]+1, $gt[3], $gt[2], $gt[1], $gt[0]); } my ($cnt, $v, @events); $cnt = 0; foreach () { $cnt++; s/#.*//; # toss comments next if /^\s*$/; # skip blank lines chomp; $v = undef; # store the raw line $v->{src} = $_; $v->{cnt} = $cnt; # split and parse the line # if we don't like it, skip it and go around again # sf[0] = date, in yyyy/mm/dd format # sf[1] = special, usually "*" # sf[2] = tag, usually "*" # sf[3] = duration, in minutes # sf[4] = time, since midnight, in minutes # sf[5] = text my @sf = split(' ', $_, 6); next unless ($sf[1] eq '*'); # ignore SPECIAL lines next unless (($sf[3] eq '*') or ($sf[3] =~ m/\d+/)); next unless (($sf[4] eq '*') or ($sf[4] =~ m/\d+/)); next unless (length($sf[5]) > 0); my @dt = split('/', $sf[0], 3); next unless ($dt[0] =~ m/^\d{4}$/); # year next unless ($dt[1] =~ m/^\d{2}$/); # month next unless ($dt[2] =~ m/^\d{2}$/); # day if ($sf[4] ne "*") { # a time was given # When an event has a time, remind -s "helpfully" also # puts it as text at the start of the text portion. # This takes the following form: # ##:##[a|p]m # or, if the event has a duration: # ##:##[a|p]m-##:##[a|p]m # Rather than a nasty regex, just splitting at the # first space does the trick. my($extra_time, $textmsg) = split(' ', $sf[5], 2); $sf[5] = $textmsg; } $v->{sf} = \@sf; $v->{dt} = \@dt; push @events, $v; } # generate the "date time string" for each event foreach $v (@events) { if (${$v->{sf}}[4] eq "*") { # no time was given $v->{dts} = sprintf("%04d%02d%02d", @{$v->{dt}}); } else { # a time was given my ($t_hr, $t_mn) = &idiv(${$v->{sf}}[4], 60); $v->{dts} = sprintf("%04d%02d%02dT%02d%02d00", @{$v->{dt}}, $t_hr, $t_mn); } } my(%grovel); # if the user doesn't want recurrence detection unless ($options{norecurr}) { # then dont put events in the grovel hash foreach $v (@events) { # key is duration followed by text # \036 is "ASCII RS Record Separator" my $k = ${$v->{sf}}[3] . "\036" . ${$v->{sf}}[5]; push @{$grovel{$k}}, $v; } foreach my $k (keys %grovel) { if ((scalar @{$grovel{$k}}) > 1) { $v = ${$grovel{$k}}[0]; $v->{recurlist} = \@{$grovel{$k}}; foreach my $v0 (@{$grovel{$k}}) { $v0->{is_recurrence} = $v; } } } } # All of the individual events are in the @events array. All of the # unique combinations of duration/event name are the keys in the # %grovel hash, the elements of which are references to an arrays of # references to the events, in the same ordering as they we read by # us, which *ought* to be in datewise order. I don't know if "remind # -s" actually sorts into true chronological order. If it doesn't, we # might have a problem if a recurring event has two instances both on # the first day. # Every event that is recurring has a "is_recurrence" property. # Additionally, (hopefully) the first/earliest event in a set of # recurrences has a "recurlist" property. The "recurlist" is a # reference to a list of references to each of the events. The first # one on that list will be the same event that has the "recurlist" # property. The "is_recurrence" property is a reference back to the # event that has the "recurlist" property. foreach my $k (keys %grovel) { next if ((scalar @{$grovel{$k}}) <= 1); my $recur_str = ""; foreach $v (@{$grovel{$k}}) { if (${$v->{sf}}[4] eq "*") { # no time was given $recur_str .= ($v->{dts} . ","); } else { if (defined($ical_tzid)) { if ($ical_tzid eq '') { # tz is defined but empty, so in GMT $recur_str .= $v->{dts} . "Z,"; } else { # tz is non-zero, so output the tz as well $recur_str .= $v->{dts} . ","; } } else { # undefined tz, just floating time $recur_str .= $v->{dts} . ","; } } } # the recur_str now has an extra comma at the end. chop it off chop($recur_str); ${$grovel{$k}}[0]->{recur_str} = $recur_str; } foreach my $k (keys %grovel) { next if ((scalar @{$grovel{$k}}) <= 1); my $v = ${$grovel{$k}}[0]; # grab the head of each list if (${$v->{sf}}[4] eq "*") { # no time was given # the default value type for an RDATE is DATE-TIME, # we much change the type to DATE $v->{i_rdate} = sprintf("RDATE;VALUE=DATE:"); } else { if (defined($ical_tzid)) { if ($ical_tzid eq '') { # tz is defined but empty, so in GMT $v->{i_rdate} = sprintf("RDATE:"); } else { # tz is non-zero, so output the tz as well $v->{i_rdate} = sprintf("RDATE;TZID=%s:", $ical_tzid); } } else { # undefined tz, just floating time $v->{i_rdate} = sprintf("RDATE:"); } } # now stick the recur_str onto the end $v->{i_rdate} .= $v->{recur_str}; # if we ever get memory tight, we can probably undef($v->{recur_str}) } foreach $v (@events) { # for recurrent events, skip those that arnt the "head" next if ($v->{is_recurrence} and (not $v->{recurlist})); if (${$v->{sf}}[4] eq "*") { # no time was given $v->{i_dtstart} = sprintf("DTSTART:%s", $v->{dts}); } else { if (defined($ical_tzid)) { if ($ical_tzid eq '') { # tz is defined but empty, so in GMT $v->{i_dtstart} = sprintf("DTSTART:%sZ", $v->{dts}); } else { # tz is non-zero, so output the tz as well $v->{i_dtstart} = sprintf("DTSTART;TZID=%s:%s", $ical_tzid, $v->{dts}); } } else { # undefined tz, just floating time $v->{i_dtstart} = sprintf("DTSTART:%s", $v->{dts}); } } if (${$v->{sf}}[3] ne "*") { # a duration was given # It's convenient that RFC2445 defines DURATION, thus we # don't need to calculate DTEND, with awkward figuring out # crossing hours, days, months, year, etc. Instead we # will let the iCalendar consuming application worry about it. $v->{i_duration} = sprintf("PT%dM", ${$v->{sf}}[3]); } } # output header print "BEGIN:VCALENDAR\015\012" . "VERSION:2.0\015\012" . "PRODID:http://mark.atwood.name/code/rem2ics" . " $app_name $app_version\015\012"; # output each vevent foreach $v (@events) { # for recurrent events, only output the "head", skip the others next if ($v->{is_recurrence} and (not $v->{recurlist})); print "BEGIN:VEVENT\015\012"; my $tag = ${$v->{sf}}[2]; # if $tag is not set, fake up a UID from start time, process id & input line count if ($tag eq "*" || !$options{usetag}) { $tag = sprintf("%x.%x.%x", $^T, $$, $v->{cnt}); } # add rem2ics and hostname to UID print &lineify(sprintf("UID:rem2ics.%s@%s", $tag, $ical_uid_hostname)); print &lineify("SUMMARY:" . "ify(${$v->{sf}}[5])); print &lineify($v->{i_dtstart}); print &lineify("DURATION:" . $v->{i_duration}) if ($v->{i_duration}); print &lineify($v->{i_rdate}) if ($v->{i_rdate}); print &lineify("DTSTAMP:" . $ical_dtstamp); print &lineify("COMMENT: generated by $app_name $app_version\\n" . " http://mark.atwood.name/code/rem2ics\\n" . " data[" . $v->{cnt} . "]=|" . "ify($v->{src}) . "|"); print "END:VEVENT\015\012"; } # output trailer print "END:VCALENDAR\015\012"; # integer division, return both quotient and remainder sub idiv { my $n = shift; my $d = shift; my $r = $n; my $q = 0; while ($r >= $d) { $r = $r - $d; $q = $q + 1; } return ($q, $r); } # todo, perl5 version that defines ()*, need to specify a requires up top sub lineify { return join("\015\012 ", unpack('(A72)*', shift)) . "\015\012"; } sub quotify { my $s = shift; return $s if $s =~ m/^(\w| )*$/; $s =~ s/\\/\\\\/gso; $s =~ s/\n/\\n/gso; $s =~ s/\s/ /gso; $s =~ s/\"/\\"/gso; $s =~ s/\,/\\,/gso; $s =~ s/\:/\\:/gso; $s =~ s/\;/\\;/gso; return $s; } __END__ GNU GENERAL PUBLIC LICENSE Version 2, June 1991 Copyright (C) 1989, 1991 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 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