ikiwiki/IkiWiki/Plugin/trail.pm

467 lines
11 KiB
Perl

#!/usr/bin/perl
# Copyright © 2008-2011 Joey Hess
# Copyright © 2009-2012 Simon McVittie <http://smcv.pseudorandom.co.uk/>
# Licensed under the GNU GPL, version 2, or any later version published by the
# Free Software Foundation
package IkiWiki::Plugin::trail;
use warnings;
use strict;
use IkiWiki 3.00;
sub import {
hook(type => "getsetup", id => "trail", call => \&getsetup);
hook(type => "needsbuild", id => "trail", call => \&needsbuild);
hook(type => "preprocess", id => "trailoptions", call => \&preprocess_trailoptions, scan => 1);
hook(type => "preprocess", id => "trailitem", call => \&preprocess_trailitem, scan => 1);
hook(type => "preprocess", id => "trailitems", call => \&preprocess_trailitems, scan => 1);
hook(type => "preprocess", id => "traillink", call => \&preprocess_traillink, scan => 1);
hook(type => "pagetemplate", id => "trail", call => \&pagetemplate);
hook(type => "build_affected", id => "trail", call => \&build_affected);
}
# Page state
#
# If a page $T is a trail, then it can have
#
# * $pagestate{$T}{trail}{contents}
# Reference to an array of lists each containing either:
# - [pagenames => "page1", "page2"]
# Those literal pages
# - [link => "link"]
# A link specification, pointing to the same page that [[link]]
# would select
# - [pagespec => "posts/*", "age", 0]
# A match by pagespec; the third array element is the sort order
# and the fourth is whether to reverse sorting
#
# * $pagestate{$T}{trail}{sort}
# A sorting order; if absent or undef, the trail is in the order given
# by the links that form it
#
# * $pagestate{$T}{trail}{circular}
# True if this trail is circular (i.e. going "next" from the last item is
# allowed, and takes you back to the first)
#
# * $pagestate{$T}{trail}{reverse}
# True if C<sort> is to be reversed.
#
# If a page $M is a member of a trail $T, then it has
#
# * $pagestate{$M}{trail}{item}{$T}[0]
# The page before this one in C<$T> at the last rebuild, or undef.
#
# * $pagestate{$M}{trail}{item}{$T}[1]
# The page after this one in C<$T> at the last refresh, or undef.
sub getsetup () {
return
plugin => {
safe => 1,
rebuild => undef,
},
}
# Cache of pages' old titles, so we can tell whether they changed
my %old_trail_titles;
sub needsbuild (@) {
my $needsbuild=shift;
foreach my $page (keys %pagestate) {
if (exists $pagestate{$page}{trail}) {
if (exists $pagesources{$page} &&
grep { $_ eq $pagesources{$page} } @$needsbuild) {
# Remember its title, so we can know whether
# it changed.
$old_trail_titles{$page} = title_of($page);
# Remove state, it will be re-added
# if the preprocessor directive is still
# there during the rebuild. {item} is the
# only thing that's added for items, not
# trails, and it's harmless to delete that -
# the item is being rebuilt anyway.
delete $pagestate{$page}{trail};
}
}
}
return $needsbuild;
}
my $scanned = 0;
sub preprocess_trailoptions (@) {
my %params = @_;
if (exists $params{circular}) {
$pagestate{$params{page}}{trail}{circular} =
IkiWiki::yesno($params{circular});
}
if (exists $params{sort}) {
$pagestate{$params{page}}{trail}{sort} = $params{sort};
}
if (exists $params{reverse}) {
$pagestate{$params{page}}{trail}{reverse} = $params{reverse};
}
return "";
}
sub preprocess_trailitem (@) {
my $link = shift;
shift;
# avoid collecting everything in the preprocess stage if we already
# did in the scan stage
if (defined wantarray) {
return "" if $scanned;
}
else {
$scanned = 1;
}
my %params = @_;
my $trail = $params{page};
$link = linkpage($link);
add_link($params{page}, $link, 'trail');
push @{$pagestate{$params{page}}{trail}{contents}}, [link => $link];
return "";
}
sub preprocess_trailitems (@) {
my %params = @_;
# avoid collecting everything in the preprocess stage if we already
# did in the scan stage
if (defined wantarray) {
return "" if $scanned;
}
else {
$scanned = 1;
}
# trail members from a pagespec ought to be in some sort of order,
# and path is a nice obvious default
$params{sort} = 'path' unless exists $params{sort};
$params{reverse} = 'no' unless exists $params{reverse};
if (exists $params{pages}) {
push @{$pagestate{$params{page}}{trail}{contents}},
["pagespec" => $params{pages}, $params{sort},
IkiWiki::yesno($params{reverse})];
}
if (exists $params{pagenames}) {
push @{$pagestate{$params{page}}{trail}{contents}},
[pagenames => (map { linkpage $_ } split ' ', $params{pagenames})];
}
return "";
}
sub preprocess_traillink (@) {
my $link = shift;
shift;
my %params = @_;
my $trail = $params{page};
$link =~ qr{
(?:
([^\|]+) # 1: link text
\| # followed by |
)? # optional
(.+) # 2: page to link to
}x;
my $linktext = $1;
$link = linkpage($2);
add_link($params{page}, $link, 'trail');
# avoid collecting everything in the preprocess stage if we already
# did in the scan stage
my $already;
if (defined wantarray) {
$already = $scanned;
}
else {
$scanned = 1;
}
push @{$pagestate{$params{page}}{trail}{contents}}, [link => $link] unless $already;
if (defined $linktext) {
$linktext = pagetitle($linktext);
}
if (exists $params{text}) {
$linktext = $params{text};
}
if (defined $linktext) {
return htmllink($trail, $params{destpage},
$link, linktext => $linktext);
}
return htmllink($trail, $params{destpage}, $link);
}
# trail => [member1, member2]
my %trail_to_members;
# member => { trail => [prev, next] }
# e.g. if %trail_to_members = (
# trail1 => ["member1", "member2"],
# trail2 => ["member0", "member1"],
# )
#
# then $member_to_trails{member1} = {
# trail1 => [undef, "member2"],
# trail2 => ["member0", undef],
# }
my %member_to_trails;
# member => 1
my %rebuild_trail_members;
sub trails_differ {
my ($old, $new) = @_;
foreach my $trail (keys %$old) {
if (! exists $new->{$trail}) {
return 1;
}
if (exists $old_trail_titles{$trail} &&
title_of($trail) ne $old_trail_titles{$trail}) {
return 1;
}
my ($old_p, $old_n) = @{$old->{$trail}};
my ($new_p, $new_n) = @{$new->{$trail}};
$old_p = "" unless defined $old_p;
$old_n = "" unless defined $old_n;
$new_p = "" unless defined $new_p;
$new_n = "" unless defined $new_n;
if ($old_p ne $new_p) {
return 1;
}
if (exists $old_trail_titles{$old_p} &&
title_of($old_p) ne $old_trail_titles{$old_p}) {
return 1;
}
if ($old_n ne $new_n) {
return 1;
}
if (exists $old_trail_titles{$old_n} &&
title_of($old_n) ne $old_trail_titles{$old_n}) {
return 1;
}
}
foreach my $trail (keys %$new) {
if (! exists $old->{$trail}) {
return 1;
}
}
return 0;
}
my $done_prerender = 0;
sub prerender {
return if $done_prerender;
%trail_to_members = ();
%member_to_trails = ();
foreach my $trail (keys %pagestate) {
next unless exists $pagestate{$trail}{trail}{contents};
my $members = [];
my @contents = @{$pagestate{$trail}{trail}{contents}};
foreach my $c (@contents) {
if ($c->[0] eq 'pagespec') {
push @$members, pagespec_match_list($trail,
$c->[1], sort => $c->[2],
reverse => $c->[3]);
}
elsif ($c->[0] eq 'pagenames') {
my @pagenames = @$c;
shift @pagenames;
foreach my $page (@pagenames) {
if (exists $pagesources{$page}) {
push @$members, $page;
}
else {
# rebuild trail if it turns up
add_depends($trail, $page, deptype("presence"));
}
}
}
elsif ($c->[0] eq 'link') {
my $best = bestlink($trail, $c->[1]);
push @$members, $best if length $best;
}
}
if (defined $pagestate{$trail}{trail}{sort}) {
@$members = IkiWiki::sort_pages(
$pagestate{$trail}{trail}{sort},
$members);
}
if (IkiWiki::yesno $pagestate{$trail}{trail}{reverse}) {
@$members = reverse @$members;
}
# uniquify
my %seen;
my @tmp;
foreach my $member (@$members) {
push @tmp, $member unless $seen{$member};
$seen{$member} = 1;
}
$members = [@tmp];
for (my $i = 0; $i <= $#$members; $i++) {
my $member = $members->[$i];
my $prev;
$prev = $members->[$i - 1] if $i > 0;
my $next = $members->[$i + 1];
$member_to_trails{$member}{$trail} = [$prev, $next];
}
if ((scalar @$members) > 1 && $pagestate{$trail}{trail}{circular}) {
$member_to_trails{$members->[0]}{$trail}[0] = $members->[$#$members];
$member_to_trails{$members->[$#$members]}{$trail}[1] = $members->[0];
}
$trail_to_members{$trail} = $members;
}
foreach my $member (keys %pagestate) {
if (exists $pagestate{$member}{trail}{item} &&
! exists $member_to_trails{$member}) {
$rebuild_trail_members{$member} = 1;
delete $pagestate{$member}{trail}{item};
}
}
foreach my $member (keys %member_to_trails) {
if (! exists $pagestate{$member}{trail}{item}) {
$rebuild_trail_members{$member} = 1;
}
else {
if (trails_differ($pagestate{$member}{trail}{item},
$member_to_trails{$member})) {
$rebuild_trail_members{$member} = 1;
}
}
$pagestate{$member}{trail}{item} = $member_to_trails{$member};
}
$done_prerender = 1;
}
sub build_affected {
my %affected;
# In principle we might not have done this yet, although in practice
# at least the trail itself has probably changed, and its template
# almost certainly contains TRAILS or TRAILLOOP, triggering our
# prerender as a side-effect.
prerender();
foreach my $member (keys %rebuild_trail_members) {
$affected{$member} = sprintf(gettext("building %s, its previous or next page has changed"), $member);
}
return %affected;
}
sub title_of ($) {
my $page = shift;
if (defined ($pagestate{$page}{meta}{title})) {
return $pagestate{$page}{meta}{title};
}
return pagetitle(IkiWiki::basename($page));
}
my $recursive = 0;
sub pagetemplate (@) {
my %params = @_;
my $page = $params{page};
my $template = $params{template};
return unless length $page;
if ($template->query(name => 'trails') && ! $recursive) {
prerender();
$recursive = 1;
my $inner = template("trails.tmpl", blind_cache => 1);
IkiWiki::run_hooks(pagetemplate => sub {
shift->(%params, template => $inner)
});
$template->param(trails => $inner->output);
$recursive = 0;
}
if ($template->query(name => 'trailloop')) {
prerender();
my @trails;
# sort backlinks by page name to have a consistent order
foreach my $trail (sort keys %{$member_to_trails{$page}}) {
my $members = $trail_to_members{$trail};
my ($prev, $next) = @{$member_to_trails{$page}{$trail}};
my ($prevurl, $nexturl, $prevtitle, $nexttitle);
if (defined $prev) {
$prevurl = urlto($prev, $page);
$prevtitle = title_of($prev);
}
if (defined $next) {
$nexturl = urlto($next, $page);
$nexttitle = title_of($next);
}
push @trails, {
prevpage => $prev,
prevtitle => $prevtitle,
prevurl => $prevurl,
nextpage => $next,
nexttitle => $nexttitle,
nexturl => $nexturl,
trailpage => $trail,
trailtitle => title_of($trail),
trailurl => urlto($trail, $page),
};
}
$template->param(trailloop => \@trails);
}
}
1;