path: root/IkiWiki/Plugin/meta.pm

#!/usr/bin/perl
# Ikiwiki metadata plugin.
package IkiWiki::Plugin::meta;

use warnings;
use strict;
use IkiWiki 3.00;

my %metaheaders;

sub import {
    hook(type => "getsetup", id => "meta", call => \&getsetup);
    hook(type => "needsbuild", id => "meta", call => \&needsbuild);
    hook(type => "preprocess", id => "meta", call => \&preprocess, scan => 1);
    hook(type => "pagetemplate", id => "meta", call => \&pagetemplate);
}

sub getsetup () {
    return
        plugin => {
            safe => 1,
            rebuild => undef,
            section => "core",
        },
}

sub needsbuild (@) {
    my $needsbuild=shift;
    foreach my $page (keys %pagestate) {
        if (exists $pagestate{$page}{meta}) {
            if (exists $pagesources{$page} &&
                grep { $_ eq $pagesources{$page} } @$needsbuild) {
                # remove state, it will be re-added
                # if the preprocessor directive is still
                # there during the rebuild
                delete $pagestate{$page}{meta};
            }
        }
    }
    return $needsbuild;
}

sub scrub ($$$) {
    if (IkiWiki::Plugin::htmlscrubber->can("sanitize")) {
        return IkiWiki::Plugin::htmlscrubber::sanitize(
            content => shift, page => shift, destpage => shift);
    }
    else {
        return shift;
    }
}

sub safeurl ($) {
    my $url=shift;
    if (exists $IkiWiki::Plugin::htmlscrubber::{safe_url_regexp} &&
        defined $IkiWiki::Plugin::htmlscrubber::safe_url_regexp) {
        return $url=~/$IkiWiki::Plugin::htmlscrubber::safe_url_regexp/;
    }
    else {
        return 1;
    }
}

sub htmlize ($$$) {
    my $page = shift;
    my $destpage = shift;

    return IkiWiki::htmlize($page, $destpage, pagetype($pagesources{$page}),
        IkiWiki::linkify($page, $destpage,
        IkiWiki::preprocess($page, $destpage, shift)));
}

sub preprocess (@) {
    return "" unless @_;
    my %params=@_;
    my $key=shift;
    my $value=$params{$key};
    delete $params{$key};
    my $page=$params{page};
    delete $params{page};
    my $destpage=$params{destpage};
    delete $params{destpage};
    delete $params{preview};

    eval q{use HTML::Entities};
    # Always decode, even if encoding later, since it might not be
    # fully encoded.
    $value=decode_entities($value);

    # Metadata collection that needs to happen during the scan pass.
    if ($key eq 'title') {
        $pagestate{$page}{meta}{title}=$value;
        if (exists $params{sortas}) {
            $pagestate{$page}{meta}{titlesort}=$params{sortas};
        }
        else {
            delete $pagestate{$page}{meta}{titlesort};
        }
        return "";
    }
    elsif ($key eq 'description') {
        $pagestate{$page}{meta}{description}=$value;
        # fallthrough
    }
    elsif ($key eq 'guid') {
        $pagestate{$page}{meta}{guid}=$value;
        # fallthrough
    }
    elsif ($key eq 'license') {
        push @{$metaheaders{$page}}, '<link rel="license" href="#page_license" />';
        $pagestate{$page}{meta}{license}=$value;
        return "";
    }
    elsif ($key eq 'copyright') {
        push @{$metaheaders{$page}}, '<link rel="copyright" href="#page_copyright" />';
        $pagestate{$page}{meta}{copyright}=$value;
        return "";
    }
    elsif ($key eq 'link' && ! %params) {
        # hidden WikiLink
        add_link($page, $value);
        return "";
    }
    elsif ($key eq 'author') {
        $pagestate{$page}{meta}{author}=$value;
        if (exists $params{sortas}) {
            $pagestate{$page}{meta}{authorsort}=$params{sortas};
        }
        else {
            delete $pagestate{$page}{meta}{authorsort};
        }
        # fallthorough
    }
    elsif ($key eq 'authorurl') {
        $pagestate{$page}{meta}{authorurl}=$value if safeurl($value);
        # fallthrough
    }
    elsif ($key eq 'permalink') {
        $pagestate{$page}{meta}{permalink}=$value if safeurl($value);
        # fallthrough
    }
    elsif ($key eq 'date') {
        eval q{use Date::Parse};
        if (! $@) {
            my $time = str2time($value);
            $IkiWiki::pagectime{$page}=$time if defined $time;
        }
    }
    elsif ($key eq 'updated') {
        eval q{use Date::Parse};
        if (! $@) {
            my $time = str2time($value);
            $pagestate{$page}{meta}{updated}=$time if defined $time;
        }
    }

    if (! defined wantarray) {
        # avoid collecting duplicate data during scan pass
        return;
    }

    # Metadata handling that happens only during preprocessing pass.
    if ($key eq 'permalink') {
        if (safeurl($value)) {
            push @{$metaheaders{$page}}, scrub('<link rel="bookmark" href="'.encode_entities($value).'" />', $page, $destpage);
        }
    }
    elsif ($key eq 'stylesheet') {
        my $rel=exists $params{rel} ? $params{rel} : "alternate stylesheet";
        my $title=exists $params{title} ? $params{title} : $value;
        # adding .css to the value prevents using any old web
        # editable page as a stylesheet
        my $stylesheet=bestlink($page, $value.".css");
        if (! length $stylesheet) {
            error gettext("stylesheet not found")
        }
        push @{$metaheaders{$page}}, scrub('<link href="'.urlto($stylesheet, $page).
            '" rel="'.encode_entities($rel).
            '" title="'.encode_entities($title).
            "\" type=\"text/css\" />", $page, $destpage);
    }
    elsif ($key eq 'script') {
        my $defer=exists $params{defer} ? ' defer="defer"' : '';
        my $async=exists $params{async} ? ' async="async"' : '';
        my $js=bestlink($page, $value.".js");
        if (! length $js) {
            error gettext("script not found");
        }
        push @{$metaheaders{$page}}, scrub('<script src="'.urlto($js, $page).
            '"' . $defer . $async . ' type="text/javascript"></script>',
            $page, $destpage);
    }
    elsif ($key eq 'openid') {
        my $delegate=0; # both by default
        if (exists $params{delegate}) {
            $delegate = 1 if lc $params{delegate} eq 'openid';
            $delegate = 2 if lc $params{delegate} eq 'openid2';
        }
        if (exists $params{server} && safeurl($params{server})) {
            push @{$metaheaders{$page}}, '<link href="'.encode_entities($params{server}).
                '" rel="openid.server" />' if $delegate ne 2;
            push @{$metaheaders{$page}}, '<link href="'.encode_entities($params{server}).
                '" rel="openid2.provider" />' if $delegate ne 1;
        }
        if (safeurl($value)) {
            push @{$metaheaders{$page}}, '<link href="'.encode_entities($value).
                '" rel="openid.delegate" />' if $delegate ne 2;
            push @{$metaheaders{$page}}, '<link href="'.encode_entities($value).
                '" rel="openid2.local_id" />' if $delegate ne 1;
        }
        if (exists $params{"xrds-location"} && safeurl($params{"xrds-location"})) {
            # force url absolute
            eval q{use URI};
            error($@) if $@;
            my $url=URI->new_abs($params{"xrds-location"}, $config{url});
            push @{$metaheaders{$page}}, '<meta http-equiv="X-XRDS-Location" '.
                'content="'.encode_entities($url).'" />';
        }
    }
    elsif ($key eq 'foaf') {
        if (safeurl($value)) {
            push @{$metaheaders{$page}}, '<link rel="meta" '.
                'type="application/rdf+xml" title="FOAF" '.
                'href="'.encode_entities($value).'" />';
        }
    }
    elsif ($key eq 'redir') {
        return "" if $page ne $destpage;
        my $safe=0;
        if ($value !~ /^\w+:\/\//) {
            my ($redir_page, $redir_anchor) = split /\#/, $value;

            my $link=bestlink($page, $redir_page);
            if (! length $link) {
                error gettext("redir page not found")
            }
            add_depends($page, $link, deptype("presence"));

            $value=urlto($link, $page);
            $value.='#'.$redir_anchor if defined $redir_anchor;
            $safe=1;

            # redir cycle detection
            $pagestate{$page}{meta}{redir}=$link;
            my $at=$page;
            my %seen;
            while (exists $pagestate{$at}{meta}{redir}) {
                if ($seen{$at}) {
                    error gettext("redir cycle is not allowed")
                }
                $seen{$at}=1;
                $at=$pagestate{$at}{meta}{redir};
            }
        }
        else {
            $value=encode_entities($value);
        }
        my $delay=int(exists $params{delay} ? $params{delay} : 0);
        my $redir="<meta http-equiv=\"refresh\" content=\"$delay; URL=$value\" />";
        if (! $safe) {
            $redir=scrub($redir, $page, $destpage);
        }
        push @{$metaheaders{$page}}, $redir;
    }
    elsif ($key eq 'link') {
        if (%params) {
            push @{$metaheaders{$page}}, scrub("<link href=\"".encode_entities($value)."\" ".
                join(" ", map {
                    encode_entities($_)."=\"".encode_entities(decode_entities($params{$_}))."\""
                } keys %params).
                " />\n", $page, $destpage);
        }
    }
    elsif ($key eq 'robots') {
        push @{$metaheaders{$page}}, '<meta name="robots"'.
            ' content="'.encode_entities($value).'" />';
    }
    elsif ($key eq 'description' || $key eq 'author') {
        push @{$metaheaders{$page}}, '<meta name="'.$key.
            '" content="'.encode_entities($value).'" />';
    }
    elsif ($key eq 'name') {
        push @{$metaheaders{$page}}, scrub('<meta name="'.
            encode_entities($value).
            join(' ', map { "$_=\"$params{$_}\"" } keys %params).
            ' />', $page, $destpage);
    }
    elsif ($key eq 'keywords') {
        # Make sure the keyword string is safe: only allow alphanumeric
        # characters, space and comma and strip the rest.
        $value =~ s/[^[:alnum:], ]+//g;
        push @{$metaheaders{$page}}, '<meta name="keywords"'.
            ' content="'.encode_entities($value).'" />';
    }
    else {
        push @{$metaheaders{$page}}, scrub('<meta name="'.
            encode_entities($key).'" content="'.
            encode_entities($value).'" />', $page, $destpage);
    }

    return "";
}

sub pagetemplate (@) {
    my %params=@_;
        my $page=$params{page};
        my $destpage=$params{destpage};
        my $template=$params{template};

    if (exists $metaheaders{$page} && $template->query(name => "meta")) {
        # avoid duplicate meta lines
        my %seen;
        $template->param(meta => join("\n", grep { (! $seen{$_}) && ($seen{$_}=1) } @{$metaheaders{$page}}));
    }
    if (exists $pagestate{$page}{meta}{title} && $template->query(name => "title")) {
        eval q{use HTML::Entities};
        $template->param(title => HTML::Entities::encode_numeric($pagestate{$page}{meta}{title}));
        $template->param(title_overridden => 1);
    }

    foreach my $field (qw{authorurl}) {
        eval q{use HTML::Entities};
        $template->param($field => HTML::Entities::encode_entities($pagestate{$page}{meta}{$field}))
            if exists $pagestate{$page}{meta}{$field} && $template->query(name => $field);
    }

    foreach my $field (qw{permalink}) {
        if (exists $pagestate{$page}{meta}{$field} && $template->query(name => $field)) {
            eval q{use HTML::Entities};
            $template->param($field => HTML::Entities::encode_entities(IkiWiki::urlabs($pagestate{$page}{meta}{$field}, $config{url})));
        }
    }

    foreach my $field (qw{description author}) {
        eval q{use HTML::Entities};
        $template->param($field => HTML::Entities::encode_numeric($pagestate{$page}{meta}{$field}))
            if exists $pagestate{$page}{meta}{$field} && $template->query(name => $field);
    }

    foreach my $field (qw{license copyright}) {
        if (exists $pagestate{$page}{meta}{$field} && $template->query(name => $field) &&
            ($page eq $destpage || ! exists $pagestate{$destpage}{meta}{$field} ||
             $pagestate{$page}{meta}{$field} ne $pagestate{$destpage}{meta}{$field})) {
            $template->param($field => htmlize($page, $destpage, $pagestate{$page}{meta}{$field}));
        }
    }
}

sub get_sort_key {
    my $page = shift;
    my $meta = shift;

    # e.g. titlesort (also makes sense for author)
    my $key = $pagestate{$page}{meta}{$meta . "sort"};
    return $key if defined $key;

    # e.g. title
    $key = $pagestate{$page}{meta}{$meta};
    return $key if defined $key;

    # fall back to closer-to-core things
    if ($meta eq 'title') {
        return pagetitle(IkiWiki::basename($page));
    }
    elsif ($meta eq 'date') {
        return $IkiWiki::pagectime{$page};
    }
    elsif ($meta eq 'updated') {
        return $IkiWiki::pagemtime{$page};
    }
    else {
        return '';
    }
}

sub match {
    my $field=shift;
    my $page=shift;
    
    # turn glob into a safe regexp
    my $re=IkiWiki::glob2re(shift);

    my $val;
    if (exists $pagestate{$page}{meta}{$field}) {
        $val=$pagestate{$page}{meta}{$field};
    }
    elsif ($field eq 'title') {
        $val = pagetitle($page);
    }

    if (defined $val) {
        if ($val=~$re) {
            return IkiWiki::SuccessReason->new("$re matches $field of $page", $page => $IkiWiki::DEPEND_CONTENT, "" => 1);
        }
        else {
            return IkiWiki::FailReason->new("$re does not match $field of $page", $page => $IkiWiki::DEPEND_CONTENT, "" => 1);
        }
    }
    else {
        return IkiWiki::FailReason->new("$page does not have a $field", $page => $IkiWiki::DEPEND_CONTENT);
    }
}

package IkiWiki::PageSpec;

sub match_title ($$;@) {
    IkiWiki::Plugin::meta::match("title", @_);
}

sub match_author ($$;@) {
    IkiWiki::Plugin::meta::match("author", @_);
}

sub match_authorurl ($$;@) {
    IkiWiki::Plugin::meta::match("authorurl", @_);
}

sub match_license ($$;@) {
    IkiWiki::Plugin::meta::match("license", @_);
}

sub match_copyright ($$;@) {
    IkiWiki::Plugin::meta::match("copyright", @_);
}

sub match_guid ($$;@) {
    IkiWiki::Plugin::meta::match("guid", @_);
}

package IkiWiki::SortSpec;

sub cmp_meta {
    my $meta = shift;
    error(gettext("sort=meta requires a parameter")) unless defined $meta;

    if ($meta eq 'updated' || $meta eq 'date') {
        return IkiWiki::Plugin::meta::get_sort_key($a, $meta)
            <=>
            IkiWiki::Plugin::meta::get_sort_key($b, $meta);
    }

    return IkiWiki::Plugin::meta::get_sort_key($a, $meta)
        cmp
        IkiWiki::Plugin::meta::get_sort_key($b, $meta);
}

# A prototype of how sort=title could behave in 4.0 or something
sub cmp_meta_title {
    $_[0] = 'title';
    return cmp_meta(@_);
}

1