]> git.vanrenterghem.biz Git - git.ikiwiki.info.git/blobdiff - IkiWiki/Plugin/calendar.pm
rename postvote to postlink
[git.ikiwiki.info.git] / IkiWiki / Plugin / calendar.pm
index 9cbfd769d381a4aa2cf8ca95a0bb74fa3b330ef2..45617afe82d9af5b8ce8c4632df02e8a6c827580 100644 (file)
@@ -1,4 +1,4 @@
-#! /usr/bin/perl
+#!/usr/bin/perl
 # Copyright (c) 2006, 2007 Manoj Srivastava <srivasta@debian.org>
 #
 # This program is free software; you can redistribute it and/or modify
@@ -13,7 +13,7 @@
 #
 # 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
 
 require 5.002;
 package IkiWiki::Plugin::calendar;
@@ -22,15 +22,20 @@ use warnings;
 use strict;
 use IkiWiki 3.00;
 use Time::Local;
-use POSIX;
 
 my $time=time;
 my @now=localtime($time);
+my %changed;
 
 sub import {
+       hook(type => "checkconfig", id => "calendar", call => \&checkconfig);
        hook(type => "getsetup", id => "calendar", call => \&getsetup);
        hook(type => "needsbuild", id => "calendar", call => \&needsbuild);
        hook(type => "preprocess", id => "calendar", call => \&preprocess);
+       hook(type => "scan", id => "calendar", call => \&scan);
+       hook(type => "build_affected", id => "calendar", call => \&build_affected);
+
+       IkiWiki::loadplugin("transient");
 }
 
 sub getsetup () {
@@ -38,6 +43,7 @@ sub getsetup () {
                plugin => {
                        safe => 1,
                        rebuild => undef,
+                       section => "widget",
                },
                archivebase => {
                        type => "string",
@@ -46,6 +52,44 @@ sub getsetup () {
                        safe => 1,
                        rebuild => 1,
                },
+               archive_pagespec => {
+                       type => "pagespec",
+                       example => "page(posts/*) and !*/Discussion",
+                       description => "PageSpec of pages to include in the archives, if option `calendar_autocreate` is true.",
+                       link => 'ikiwiki/PageSpec',
+                       safe => 1,
+                       rebuild => 0,
+               },
+               calendar_autocreate => {
+                       type => "boolean",
+                       example => 1,
+                       description => "autocreate new calendar pages?",
+                       safe => 1,
+                       rebuild => undef,
+               },
+               calendar_fill_gaps => {
+                       type => "boolean",
+                       example => 1,
+                       default => 1,
+                       description => "if set, when building calendar pages, also build pages of year and month when no pages were published (building empty calendars).",
+                       safe => 1,
+                       rebuild => 0,
+               },
+}
+
+sub checkconfig () {
+       if (! defined $config{calendar_autocreate}) {
+               $config{calendar_autocreate} = defined $config{archivebase};
+       }
+       if (! defined $config{archive_pagespec}) {
+               $config{archive_pagespec} = '*';
+       }
+       if (! defined $config{archivebase}) {
+               $config{archivebase} = 'archives';
+       }
+       if (! defined $config{calendar_fill_gaps}) {
+               $config{calendar_fill_gaps} = 1;
+       }
 }
 
 sub is_leap_year (@) {
@@ -62,27 +106,219 @@ sub month_days {
        return $days_in_month;
 }
 
+sub build_affected {
+       my %affected;
+       my ($ayear, $amonth, $valid);
+
+       foreach my $year (keys %changed) {
+               ($ayear, $valid) = nextyear($year, $config{archivebase});
+               $affected{calendarlink($ayear)} = sprintf(gettext("building calendar for %s, its previous or next year has changed"), $ayear) if ($valid);
+               ($ayear, $valid) = previousyear($year, $config{archivebase});
+               $affected{calendarlink($ayear)} = sprintf(gettext("building calendar for %s, its previous or next year has changed"), $ayear) if ($valid);
+               foreach my $month (keys %{$changed{$year}}) {
+                       ($ayear, $amonth, $valid) = nextmonth($year, $month, $config{archivebase});
+                       $affected{calendarlink($ayear, sprintf("%02d", $amonth))} = sprintf(gettext("building calendar for %s/%s, its previous or next month has changed"), $amonth, $ayear) if ($valid);
+                       ($ayear, $amonth, $valid) = previousmonth($year, $month, $config{archivebase});
+                       $affected{calendarlink($ayear, sprintf("%02d", $amonth))} = sprintf(gettext("building calendar for %s/%s, its previous or next month has changed"), $amonth, $ayear) if ($valid);
+               }
+       }
+
+       return %affected;
+}
+
+sub autocreate {
+       my ($page, $pagefile, $year, $month) = @_;
+       my $message=sprintf(gettext("creating calendar page %s"), $page);
+       debug($message);
+
+       my $template;
+       if (defined $month) {
+               $template=template("calendarmonth.tmpl");
+       } else {
+               $template=template("calendaryear.tmpl");
+       }
+       $template->param(year => $year);
+       $template->param(month => $month) if defined $month;
+       $template->param(pagespec => $config{archive_pagespec});
+
+       no warnings 'once';
+       my $dir = $IkiWiki::Plugin::transient::transientdir;
+       use warnings;
+
+       writefile($pagefile, $dir, $template->output);
+}
+
+sub calendarlink($;$) {
+       my ($year, $month) = @_;
+       if (defined $month) {
+               return $config{archivebase} . "/" . $year . "/" . $month;
+       } else {
+               return $config{archivebase} . "/" . $year;
+       }
+}
+
+sub gencalendarmonth{
+       my $year = shift;
+       my $month = sprintf("%02d", shift);
+
+       my $page = calendarlink($year, $month);
+       my $pagefile = newpagefile($page, $config{default_pageext});
+       add_autofile(
+               $pagefile, "calendar",
+               sub {return autocreate($page, $pagefile, $year, $month);}
+       );
+}
+
+sub gencalendaryear {
+       my $year = shift;
+       my %params = @_;
+
+       # Building year page
+       my $page = calendarlink($year);
+       my $pagefile = newpagefile($page, $config{default_pageext});
+       add_autofile(
+               $pagefile, "calendar",
+               sub {return autocreate($page, $pagefile, $year);}
+       );
+
+       if (not exists $wikistate{calendar}{minyear}) {
+               $wikistate{calendar}{minyear} = $year;
+       }
+       if (not exists $wikistate{calendar}{maxyear}) {
+               $wikistate{calendar}{maxyear} = $year;
+       }
+
+       if ($config{calendar_fill_gaps}) {
+               # Building month pages
+               foreach my $month (1 .. 12) {
+                       gencalendarmonth($year, $month);
+               }
+
+               # Filling potential gaps in years (e.g. calendar goes from 2010 to 2014,
+               # and we just added year 2005. We have to add years 2006 to 2009).
+               return if $params{norecurse};
+               if ($wikistate{calendar}{minyear} > $year) {
+                       foreach my $other ($year + 1 .. $wikistate{calendar}{minyear} - 1) {
+                               gencalendaryear($other, norecurse => 1);
+                       }
+                       $wikistate{calendar}{minyear} = $year;
+               }
+               if ($wikistate{calendar}{maxyear} < $year) {
+                       foreach my $other ($wikistate{calendar}{maxyear} + 1 .. $year - 1) {
+                               gencalendaryear($other, norecurse => 1);
+                       }
+                       $wikistate{calendar}{maxyear} = $year;
+               }
+       }
+       if ($year < $wikistate{calendar}{minyear}) {
+               $wikistate{calendar}{minyear} = $year;
+       }
+       if ($year >  $wikistate{calendar}{maxyear}) {
+               $wikistate{calendar}{maxyear} = $year;
+       }
+}
+
+sub previousmonth($$$) {
+       my $year = shift;
+       my $month = shift;
+       my $archivebase = shift;
+
+       if (not exists $wikistate{calendar}{minyear}) {
+               $wikistate{calendar}{minyear} = $year;
+       }
+
+       my $pmonth = $month;
+       my $pyear  = $year;
+       while ((not exists $pagesources{"$archivebase/$pyear/" . sprintf("%02d", $pmonth)}) or ($pmonth == $month and $pyear == $year)) {
+               $pmonth -= 1;
+               if ($pmonth == 0) {
+                       $pyear -= 1;
+                       $pmonth = 12;
+                       return ($pyear, $pmonth, 0) unless $pyear >= $wikistate{calendar}{minyear};
+               }
+       }
+       return ($pyear, $pmonth, 1);
+}
+
+sub nextmonth($$$) {
+       my $year = shift;
+       my $month = shift;
+       my $archivebase = shift;
+
+       if (not exists $wikistate{calendar}{maxyear}) {
+               $wikistate{calendar}{maxyear} = $year;
+       }
+
+       my $nmonth = $month;
+       my $nyear  = $year;
+       while ((not exists $pagesources{"$archivebase/$nyear/" . sprintf("%02d", $nmonth)}) or ($nmonth == $month and $nyear == $year)) {
+               $nmonth += 1;
+               if ($nmonth == 13) {
+                       $nyear += 1;
+                       $nmonth = 1;
+                       return ($nyear, $nmonth, 0) unless $nyear <= $wikistate{calendar}{maxyear};
+               }
+       }
+       return ($nyear, $nmonth, 1);
+}
+
+sub previousyear($$) {
+       my $year = shift;
+       my $archivebase = shift;
+
+       my $pyear = $year - 1;
+       while (not exists $pagesources{"$archivebase/$pyear"}) {
+               $pyear -= 1;
+               return ($pyear, 0) unless ($pyear >= $wikistate{calendar}{minyear});
+       }
+       return ($pyear, 1);
+}
+
+sub nextyear($$) {
+       my $year = shift;
+       my $archivebase = shift;
+
+       my $nyear = $year + 1;
+       while (not exists $pagesources{"$archivebase/$nyear"}) {
+               $nyear += 1;
+               return ($nyear, 0) unless ($nyear <= $wikistate{calendar}{maxyear});
+       }
+       return ($nyear, 1);
+}
+
 sub format_month (@) {
        my %params=@_;
 
        my %linkcache;
-       foreach my $p (pagespec_match_list($params{page}, $params{pages},
+       foreach my $p (pagespec_match_list($params{page}, 
+                               "creation_year($params{year}) and creation_month($params{month}) and ($params{pages})",
                                # add presence dependencies to update
                                # month calendar when pages are added/removed
                                deptype => deptype("presence"))) {
                my $mtime = $IkiWiki::pagectime{$p};
-               my $src   = $pagesources{$p};
                my @date  = localtime($mtime);
                my $mday  = $date[3];
                my $month = $date[4] + 1;
                my $year  = $date[5] + 1900;
                my $mtag  = sprintf("%02d", $month);
 
-               # Only one posting per day is being linked to.
-               $linkcache{"$year/$mtag/$mday"} = "$src";
+               if (! $linkcache{"$year/$mtag/$mday"}) {
+                       $linkcache{"$year/$mtag/$mday"} = [];
+               }
+               push(@{$linkcache{"$year/$mtag/$mday"}}, $p);
        }
+               
+       my $archivebase = 'archives';
+       $archivebase = $config{archivebase} if defined $config{archivebase};
+       $archivebase = $params{archivebase} if defined $params{archivebase};
+       
+       my ($pyear, $pmonth, $pvalid) = previousmonth($params{year}, $params{month}, $archivebase);
+       my ($nyear, $nmonth, $nvalid) = nextmonth($params{year}, $params{month}, $archivebase);
+
+       # Add padding.
+       $pmonth=sprintf("%02d", $pmonth);
+       $nmonth=sprintf("%02d", $nmonth);
 
-       my @list;
        my $calendar="\n";
 
        # When did this month start?
@@ -96,46 +332,49 @@ sub format_month (@) {
        }
 
        # Find out month names for this, next, and previous months
-       my $monthname=POSIX::strftime("%B", @monthstart);
-       my $pmonthname=POSIX::strftime("%B", localtime(timelocal(0,0,0,1,$params{pmonth}-1,$params{pyear}-1900)));
-       my $nmonthname=POSIX::strftime("%B", localtime(timelocal(0,0,0,1,$params{nmonth}-1,$params{nyear}-1900)));
+       my $monthabbrev=strftime_utf8("%b", @monthstart);
+       my $monthname=strftime_utf8("%B", @monthstart);
+       my $pmonthname=strftime_utf8("%B", localtime(timelocal(0,0,0,1,$pmonth-1,$pyear-1900)));
+       my $nmonthname=strftime_utf8("%B", localtime(timelocal(0,0,0,1,$nmonth-1,$nyear-1900)));
 
-       my $archivebase = 'archives';
-       $archivebase = $config{archivebase} if defined $config{archivebase};
-       $archivebase = $params{archivebase} if defined $params{archivebase};
-  
        # Calculate URL's for monthly archives.
-       my ($url, $purl, $nurl)=("$monthname",'','');
+       my ($url, $purl, $nurl)=("$monthname $params{year}",'','');
        if (exists $pagesources{"$archivebase/$params{year}/$params{month}"}) {
                $url = htmllink($params{page}, $params{destpage}, 
-                       "$archivebase/$params{year}/".sprintf("%02d", $params{month}),
-                       linktext => " $monthname ");
+                       "$archivebase/$params{year}/".$params{month},
+                       noimageinline => 1,
+                       linktext => "$monthabbrev $params{year}",
+                       title => $monthname);
        }
-       add_depends($params{page}, "$archivebase/$params{year}/".sprintf("%02d", $params{month}),
+       add_depends($params{page}, "$archivebase/$params{year}/$params{month}",
                deptype("presence"));
-       if (exists $pagesources{"$archivebase/$params{pyear}/$params{pmonth}"}) {
+       if (exists $pagesources{"$archivebase/$pyear/$pmonth"}) {
                $purl = htmllink($params{page}, $params{destpage}, 
-                       "$archivebase/$params{pyear}/" . sprintf("%02d", $params{pmonth}),
-                       linktext => " $pmonthname ");
+                       "$archivebase/$pyear/$pmonth",
+                       noimageinline => 1,
+                       linktext => "\&larr;",
+                       title => $pmonthname);
        }
-       add_depends($params{page}, "$archivebase/$params{pyear}/".sprintf("%02d", $params{pmonth}),
+       add_depends($params{page}, "$archivebase/$pyear/$pmonth",
                deptype("presence"));
-       if (exists $pagesources{"$archivebase/$params{nyear}/$params{nmonth}"}) {
+       if (exists $pagesources{"$archivebase/$nyear/$nmonth"}) {
                $nurl = htmllink($params{page}, $params{destpage}, 
-                       "$archivebase/$params{nyear}/" . sprintf("%02d", $params{nmonth}),
-                       linktext => " $nmonthname ");
+                       "$archivebase/$nyear/$nmonth",
+                       noimageinline => 1,
+                       linktext => "\&rarr;",
+                       title => $nmonthname);
        }
-       add_depends($params{page}, "$archivebase/$params{nyear}/".sprintf("%02d", $params{nmonth}),
+       add_depends($params{page}, "$archivebase/$nyear/$nmonth",
                deptype("presence"));
 
        # Start producing the month calendar
        $calendar=<<EOF;
 <table class="month-calendar">
-       <caption class="month-calendar-head">
-       $purl
-       $url
-       $nurl
-       </caption>
+       <tr>
+       <th class="month-calendar-arrow">$purl</th>
+       <th class="month-calendar-head" colspan="5">$url</th>
+       <th class="month-calendar-arrow">$nurl</th>
+       </tr>
        <tr>
 EOF
 
@@ -148,11 +387,11 @@ EOF
        my %dowabbr;
        for my $dow ($week_start_day..$week_start_day+6) {
                my @day=localtime(timelocal(0,0,0,$start_day++,$params{month}-1,$params{year}-1900));
-               my $downame = POSIX::strftime("%A", @day);
-               my $dowabbr = POSIX::strftime("%a", @day);
+               my $downame = strftime_utf8("%A", @day);
+               my $dowabbr = substr($downame, 0, 1);
                $downame{$dow % 7}=$downame;
                $dowabbr{$dow % 7}=$dowabbr;
-               $calendar.= qq{\t\t<th class="month-calendar-day-head $downame">$dowabbr</th>\n};
+               $calendar.= qq{\t\t<th class="month-calendar-day-head $downame" title="$downame">$dowabbr</th>\n};
        }
 
        $calendar.=<<EOF;
@@ -170,7 +409,7 @@ EOF
        # nothing has been printed, or else we are in the middle of a row.
        for (my $day = 1; $day <= month_days(year => $params{year}, month => $params{month});
             $day++, $wday++, $wday %= 7) {
-               # At tihs point, on a week_start_day, we close out a row,
+               # At this point, on a week_start_day, we close out a row,
                # and start a new one -- unless it is week_start_day on the
                # first, where we do not close a row -- since none was started.
                if ($wday == $week_start_day) {
@@ -179,8 +418,8 @@ EOF
                }
                
                my $tag;
-               my $mtag = sprintf("%02d", $params{month});
-               if (defined $pagesources{"$archivebase/$params{year}/$mtag/$day"}) {
+               my $key="$params{year}/$params{month}/$day";
+               if (defined $linkcache{$key}) {
                        if ($day == $today) {
                                $tag='month-calendar-day-this-day';
                        }
@@ -188,10 +427,27 @@ EOF
                                $tag='month-calendar-day-link';
                        }
                        $calendar.=qq{\t\t<td class="$tag $downame{$wday}">};
-                       $calendar.=htmllink($params{page}, $params{destpage}, 
-                                           pagename($linkcache{"$params{year}/$mtag/$day"}),
-                                           "linktext" => "$day");
-                       push @list, pagename($linkcache{"$params{year}/$mtag/$day"});
+                       $calendar.=qq{<div class='popup'>$day<div class='balloon'>};
+                       # Several postings on this page
+                       $calendar.=qq{<ul>};
+                       foreach my $page (@{$linkcache{$key}}) {
+                               $calendar.= qq{\n\t\t\t<li>};
+                               my $title;
+                               if (exists $pagestate{$page}{meta}{title}) {
+                                       $title = "$pagestate{$page}{meta}{title}";
+                               }
+                               else {
+                                       $title = pagetitle(IkiWiki::basename($page));
+                               }
+                               $calendar.=htmllink($params{page}, $params{destpage}, 
+                                       $page,
+                                       noimageinline => 1,
+                                       linktext => $title,
+                                       title => $title);
+                               $calendar.= '</li>';
+                       }
+                       $calendar.=qq{\n\t\t</ul>};
+                       $calendar.=qq{</div></div>};
                        $calendar.=qq{</td>\n};
                }
                else {
@@ -223,44 +479,69 @@ EOF
 sub format_year (@) {
        my %params=@_;
 
-       my $calendar="\n";
+       my @post_months;
+       foreach my $p (pagespec_match_list($params{page}, 
+                               "creation_year($params{year}) and ($params{pages})",
+                               # add presence dependencies to update
+                               # year calendar's links to months when
+                               # pages are added/removed
+                               deptype => deptype("presence"))) {
+               my $mtime = $IkiWiki::pagectime{$p};
+               my @date  = localtime($mtime);
+               my $month = $date[4] + 1;
 
-       my $future_month = 0;
-       $future_month = $now[4]+1 if ($params{year} == $now[5]+1900);
+               $post_months[$month]++;
+       }
+               
+       my $calendar="\n";
 
        my $archivebase = 'archives';
        $archivebase = $config{archivebase} if defined $config{archivebase};
        $archivebase = $params{archivebase} if defined $params{archivebase};
+       
+       my ($pyear, $pvalid) = previousyear($params{year}, $archivebase);
+       my ($nyear, $nvalid) = nextyear($params{year}, $archivebase);
+
+       my $thisyear = $now[5]+1900;
+       my $future_month = 0;
+       $future_month = $now[4]+1 if $params{year} == $thisyear;
 
        # calculate URL's for previous and next years
        my ($url, $purl, $nurl)=("$params{year}",'','');
        if (exists $pagesources{"$archivebase/$params{year}"}) {
                $url = htmllink($params{page}, $params{destpage}, 
                        "$archivebase/$params{year}",
-                       linktext => "$params{year}");
+                       noimageinline => 1,
+                       linktext => $params{year},
+                       title => $params{year});
        }
        add_depends($params{page}, "$archivebase/$params{year}", deptype("presence"));
-       if (exists $pagesources{"$archivebase/$params{pyear}"}) {
+       if (exists $pagesources{"$archivebase/$pyear"}) {
                $purl = htmllink($params{page}, $params{destpage}, 
-                       "$archivebase/$params{pyear}",
-                       linktext => "\&larr;");
+                       "$archivebase/$pyear",
+                       noimageinline => 1,
+                       linktext => "\&larr;",
+                       title => $pyear);
        }
-       add_depends($params{page}, "$archivebase/$params{pyear}", deptype("presence"));
-       if (exists $pagesources{"$archivebase/$params{nyear}"}) {
+       add_depends($params{page}, "$archivebase/$pyear", deptype("presence"));
+       if (exists $pagesources{"$archivebase/$nyear"}) {
                $nurl = htmllink($params{page}, $params{destpage}, 
-                       "$archivebase/$params{nyear}",
-                       linktext => "\&rarr;");
+                       "$archivebase/$nyear",
+                       noimageinline => 1,
+                       linktext => "\&rarr;",
+                       title => $nyear);
        }
-       add_depends($params{page}, "$archivebase/$params{nyear}", deptype("presence"));
+       add_depends($params{page}, "$archivebase/$nyear", deptype("presence"));
 
        # Start producing the year calendar
+       my $m=$params{months_per_row}-2;
        $calendar=<<EOF;
 <table class="year-calendar">
-       <caption class="year-calendar-head">
-       $purl
-       $url
-       $nurl
-       </caption>
+       <tr>
+       <th class="year-calendar-arrow">$purl</th>
+       <th class="year-calendar-head" colspan="$m">$url</th>
+       <th class="year-calendar-arrow">$nurl</th>
+       </tr>
        <tr>
                <th class="year-calendar-subhead" colspan="$params{months_per_row}">Months</th>
        </tr>
@@ -269,33 +550,31 @@ EOF
        for (my $month = 1; $month <= 12; $month++) {
                my @day=localtime(timelocal(0,0,0,15,$month-1,$params{year}-1900));
                my $murl;
-               my $monthname = POSIX::strftime("%B", @day);
-               my $monthabbr = POSIX::strftime("%b", @day);
+               my $monthname = strftime_utf8("%B", @day);
+               my $monthabbr = strftime_utf8("%b", @day);
                $calendar.=qq{\t<tr>\n}  if ($month % $params{months_per_row} == 1);
                my $tag;
                my $mtag=sprintf("%02d", $month);
-               if ($month == $params{month}) {
-                       if ($pagesources{"$archivebase/$params{year}/$mtag"}) {
-                               $tag = 'this_month_link';
-                       }
-                       else {
-                               $tag = 'this_month_nolink';
-                       }
+               if ($month == $params{month} && $thisyear == $params{year}) {
+                       $tag = 'year-calendar-this-month';
                }
                elsif ($pagesources{"$archivebase/$params{year}/$mtag"}) {
-                       $tag = 'month_link';
+                       $tag = 'year-calendar-month-link';
                } 
                elsif ($future_month && $month >= $future_month) {
-                       $tag = 'month_future';
+                       $tag = 'year-calendar-month-future';
                } 
                else {
-                       $tag = 'month_nolink';
+                       $tag = 'year-calendar-month-nolink';
                }
 
-               if ($pagesources{"$archivebase/$params{year}/$mtag"}) {
+               if ($pagesources{"$archivebase/$params{year}/$mtag"} &&
+                   $post_months[$mtag]) {
                        $murl = htmllink($params{page}, $params{destpage}, 
                                "$archivebase/$params{year}/$mtag",
-                               linktext => "$monthabbr");
+                               noimageinline => 1,
+                               linktext => $monthabbr,
+                               title => $monthname);
                        $calendar.=qq{\t<td class="$tag">};
                        $calendar.=$murl;
                        $calendar.=qq{\t</td>\n};
@@ -316,6 +595,16 @@ EOF
        return $calendar;
 }
 
+sub setnextchange ($$) {
+       my $page=shift;
+       my $timestamp=shift;
+
+       if (! exists $pagestate{$page}{calendar}{nextchange} ||
+           $pagestate{$page}{calendar}{nextchange} > $timestamp) {
+               $pagestate{$page}{calendar}{nextchange}=$timestamp;
+       }
+}
+
 sub preprocess (@) {
        my %params=@_;
 
@@ -329,33 +618,65 @@ sub preprocess (@) {
        $params{year}  = $thisyear      unless defined $params{year};
        $params{month} = $thismonth     unless defined $params{month};
 
+       my $relativeyear=0;
+       if ($params{year} < 1) {
+               $relativeyear=1;
+               $params{year}=$thisyear+$params{year};
+       }
+       my $relativemonth=0;
+       if ($params{month} < 1) {
+               $relativemonth=1;
+               my $monthoff=$params{month};
+               $params{month}=($thismonth+$monthoff) % 12;
+               $params{month}=12 if $params{month}==0;
+               my $yearoff=POSIX::ceil(($thismonth-$params{month}) / -12)
+                       - int($monthoff / 12);
+               $params{year}-=$yearoff;
+       }
+       
        $params{month} = sprintf("%02d", $params{month});
-                       
+       $changed{$params{year}}{$params{month}} = 1;
+       
        if ($params{type} eq 'month' && $params{year} == $thisyear
            && $params{month} == $thismonth) {
                # calendar for current month, updates next midnight
-               $pagestate{$params{destpage}}{calendar}{nextchange}=($time
+               setnextchange($params{destpage}, ($time
                        + (60 - $now[0])                # seconds
                        + (59 - $now[1]) * 60           # minutes
                        + (23 - $now[2]) * 60 * 60      # hours
-               );
+               ));
        }
        elsif ($params{type} eq 'month' &&
               (($params{year} == $thisyear && $params{month} > $thismonth) ||
                $params{year} > $thisyear)) {
                # calendar for upcoming month, updates 1st of that month
-               $pagestate{$params{destpage}}{calendar}{nextchange}=
-                       timelocal(0, 0, 0, 1, $params{month}-1, $params{year});
+               setnextchange($params{destpage},
+                       timelocal(0, 0, 0, 1, $params{month}-1, $params{year}));
        }
-       elsif ($params{type} eq 'year' && $params{year} == $thisyear) {
-               # calendar for current year, updates 1st of next month
-               $pagestate{$params{destpage}}{calendar}{nextchange}=
-                       timelocal(0, 0, 0, 1, $thismonth+1-1, $params{year});
+       elsif (($params{type} eq 'year' && $params{year} == $thisyear) ||
+              $relativemonth) {
+               # Calendar for current year updates 1st of next month.
+               # Any calendar relative to the current month also updates
+               # then.
+               if ($thismonth < 12) {
+                       setnextchange($params{destpage},
+                               timelocal(0, 0, 0, 1, $thismonth+1-1, $params{year}));
+               }
+               else {
+                       setnextchange($params{destpage},
+                               timelocal(0, 0, 0, 1, 1-1, $params{year}+1));
+               }
+       }
+       elsif ($relativeyear) {
+               # Any calendar relative to the current year updates 1st
+               # of next year.
+               setnextchange($params{destpage},
+                       timelocal(0, 0, 0, 1, 1-1, $thisyear+1));
        }
        elsif ($params{type} eq 'year' && $params{year} > $thisyear) {
                # calendar for upcoming year, updates 1st of that year
-               $pagestate{$params{destpage}}{calendar}{nextchange}=
-                       timelocal(0, 0, 0, 1, 1-1, $params{year});
+               setnextchange($params{destpage},
+                       timelocal(0, 0, 0, 1, 1-1, $params{year}));
        }
        else {
                # calendar for past month or year, does not need
@@ -363,22 +684,6 @@ sub preprocess (@) {
                delete $pagestate{$params{destpage}}{calendar};
        }
 
-       # Calculate month names for next month, and previous months
-       $params{pmonth} = $params{month} - 1;
-       $params{nmonth} = $params{month} + 1;
-       $params{pyear}  = $params{year}  - 1;
-       $params{nyear}  = $params{year}  + 1;
-
-       # Adjust for January and December
-       if ($params{month} == 1) {
-               $params{pmonth} = 12;
-               $params{pyear}--;
-       }
-       if ($params{month} == 12) {
-               $params{nmonth} = 1;
-               $params{nyear}++;
-       }
-
        my $calendar="";
        if ($params{type} eq 'month') {
                $calendar=format_month(%params);
@@ -408,6 +713,22 @@ sub needsbuild (@) {
                        }
                }
        }
+
+       return $needsbuild;
+}
+
+sub scan (@) {
+       my %params=@_;
+       my $page=$params{page};
+
+       return unless $config{calendar_autocreate};
+
+       # Check if year pages have to be generated
+       if (pagespec_match($page, $config{archive_pagespec})) {
+               my @ctime = localtime($IkiWiki::pagectime{$page});
+               gencalendaryear($ctime[5]+1900);
+               gencalendarmonth($ctime[5]+1900, $ctime[4]+1);
+       }
 }
 
 1