path: root/IkiWiki/Plugin/comments.pm

#!/usr/bin/perl
# Copyright © 2006-2008 Joey Hess <joey@ikiwiki.info>
# Copyright © 2008 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::comments;

use warnings;
use strict;
use IkiWiki 2.00;
use Encode;
use POSIX qw(strftime);

use constant PREVIEW => "Preview";
use constant POST_COMMENT => "Post comment";
use constant CANCEL => "Cancel";

my $postcomment;

sub import {
    hook(type => "checkconfig", id => 'comments',  call => \&checkconfig);
    hook(type => "getsetup", id => 'comments',  call => \&getsetup);
    hook(type => "preprocess", id => '_comment', call => \&preprocess);
    hook(type => "sessioncgi", id => 'comment', call => \&sessioncgi);
    hook(type => "htmlize", id => "_comment", call => \&htmlize);
    hook(type => "pagetemplate", id => "comments", call => \&pagetemplate);
    hook(type => "cgi", id => "comments", call => \&linkcgi);
    IkiWiki::loadplugin("inline");
}

sub getsetup () {
    return
        plugin => {
            safe => 1,
            rebuild => 1,
        },
        comments_pagespec => {
            type => 'pagespec',
            example => 'blog/* and *!/Discussion',
            description => 'PageSpec of pages where comments are allowed',
            link => 'ikiwiki/PageSpec',
            safe => 1,
            rebuild => 1,
        },
        comments_closed_pagespec => {
            type => 'pagespec',
            example => 'blog/controversial or blog/flamewar',
            description => 'PageSpec of pages where posting new comments is not allowed',
            link => 'ikiwiki/PageSpec',
            safe => 1,
            rebuild => 1,
        },
        comments_pagename => {
            type => 'string',
            default => 'comment_',
            description => 'Base name for comments, e.g. "comment_" for pages like "sandbox/comment_12"',
            safe => 0, # manual page moving required
            rebuild => undef,
        },
        comments_allowdirectives => {
            type => 'boolean',
            example => 0,
            description => 'Interpret directives in comments?',
            safe => 1,
            rebuild => 0,
        },
        comments_allowauthor => {
            type => 'boolean',
            example => 0,
            description => 'Allow anonymous commenters to set an author name?',
            safe => 1,
            rebuild => 0,
        },
        comments_commit => {
            type => 'boolean',
            example => 1,
            description => 'commit comments to the VCS',
            # old uncommitted comments are likely to cause
            # confusion if this is changed
            safe => 0,
            rebuild => 0,
        },
}

sub checkconfig () {
    $config{comments_commit} = 1
        unless defined $config{comments_commit};
    $config{comments_pagespec} = ''
        unless defined $config{comments_pagespec};
    $config{comments_closed_pagespec} = ''
        unless defined $config{comments_closed_pagespec};
    $config{comments_pagename} = 'comment_'
        unless defined $config{comments_pagename};
}

sub htmlize {
    my %params = @_;
    return $params{content};
}

# FIXME: copied verbatim from meta
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 preprocess {
    my %params = @_;
    my $page = $params{page};

    my $format = $params{format};
    if (defined $format && ! exists $IkiWiki::hooks{htmlize}{$format}) {
        error(sprintf(gettext("unsupported page format %s"), $format));
    }

    my $content = $params{content};
    if (! defined $content) {
        error(gettext("comment must have content"));
    }
    $content =~ s/\\"/"/g;

    $content = IkiWiki::filter($page, $params{destpage}, $content);

    if ($config{comments_allowdirectives}) {
        $content = IkiWiki::preprocess($page, $params{destpage},
            $content);
    }

    # no need to bother with htmlize if it's just HTML
    $content = IkiWiki::htmlize($page, $params{destpage}, $format,
        $content) if defined $format;

    IkiWiki::run_hooks(sanitize => sub {
        $content = shift->(
            page => $page,
            destpage => $params{destpage},
            content => $content,
        );
    });

    # set metadata, possibly overriding [[!meta]] directives from the
    # comment itself

    my $commentuser;
    my $commentip;
    my $commentauthor;
    my $commentauthorurl;

    if (defined $params{username}) {
        $commentuser = $params{username};
        ($commentauthorurl, $commentauthor) =
            linkuser($params{username});
    }
    else {
        if (defined $params{ip}) {
            $commentip = $params{ip};
        }
        $commentauthor = gettext("Anonymous");
    }

    $pagestate{$page}{comments}{commentuser} = $commentuser;
    $pagestate{$page}{comments}{commentip} = $commentip;
    $pagestate{$page}{comments}{commentauthor} = $commentauthor;
    $pagestate{$page}{comments}{commentauthorurl} = $commentauthorurl;
    if (! defined $pagestate{$page}{meta}{author}) {
        $pagestate{$page}{meta}{author} = $commentauthor;
    }
    if (! defined $pagestate{$page}{meta}{authorurl}) {
        $pagestate{$page}{meta}{authorurl} = $commentauthorurl;
    }

    if ($config{comments_allowauthor}) {
        if (defined $params{claimedauthor}) {
            $pagestate{$page}{meta}{author} = $params{claimedauthor};
        }

        if (defined $params{url} and safeurl($params{url})) {
            $pagestate{$page}{meta}{authorurl} = $params{url};
        }
    }
    else {
        $pagestate{$page}{meta}{author} = $commentauthor;
        $pagestate{$page}{meta}{authorurl} = $commentauthorurl;
    }

    if (defined $params{subject}) {
        $pagestate{$page}{meta}{title} = $params{subject};
    }

    my $baseurl = urlto($params{destpage}, undef, 1);
    my $anchor = "";
    if ($params{page} =~ m/\/(\Q$config{comments_pagename}\E\d+)$/) {
        $anchor = $1;
    }
    $pagestate{$page}{meta}{permalink} = "${baseurl}#${anchor}";

    eval q{use Date::Parse};
    if (! $@) {
        my $time = str2time($params{date});
        $IkiWiki::pagectime{$page} = $time if defined $time;
    }

    # FIXME: hard-coded HTML (although it's just to set an ID)
    return "<div id=\"$anchor\">$content</div>" if $anchor;
    return $content;
}

# This is exactly the same as recentchanges_link :-(
sub linkcgi ($) {
    my $cgi=shift;
    if (defined $cgi->param('do') && $cgi->param('do') eq "commenter") {

        my $page=decode_utf8($cgi->param("page"));
        if (! defined $page) {
            error("missing page parameter");
        }

        IkiWiki::loadindex();

        my $link=bestlink("", $page);
        if (! length $link) {
            print "Content-type: text/html\n\n";
            print IkiWiki::misctemplate(gettext(gettext("missing page")),
                "<p>".
                sprintf(gettext("The page %s does not exist."),
                    htmllink("", "", $page)).
                "</p>");
        }
        else {
            IkiWiki::redirect($cgi, urlto($link, undef, 1));
        }

        exit;
    }
}

# FIXME: basically the same logic as recentchanges
# returns (author URL, pretty-printed version)
sub linkuser ($) {
    my $user = shift;
    my $oiduser = eval { IkiWiki::openiduser($user) };

    if (defined $oiduser) {
        return ($user, $oiduser);
    }
    # FIXME: it'd be good to avoid having such a link for anonymous
    # posts
    else {
        return (IkiWiki::cgiurl(
                do => 'commenter',
                page => (length $config{userdir}
                    ? "$config{userdir}/$user"
                    : "$user")
            ), $user);
    }
}

# Mostly cargo-culted from IkiWiki::plugin::editpage
sub sessioncgi ($$) {
    my $cgi=shift;
    my $session=shift;

    my $do = $cgi->param('do');
    return unless $do eq 'comment';

    IkiWiki::decode_cgi_utf8($cgi);

    eval q{use CGI::FormBuilder};
    error($@) if $@;

    my @buttons = (POST_COMMENT, PREVIEW, CANCEL);
    my $form = CGI::FormBuilder->new(
        fields => [qw{do sid page subject editcontent type author url}],
        charset => 'utf-8',
        method => 'POST',
        required => [qw{editcontent}],
        javascript => 0,
        params => $cgi,
        action => $config{cgiurl},
        header => 0,
        table => 0,
        template => scalar IkiWiki::template_params('comments_form.tmpl'),
        # wtf does this do in editpage?
        wikiname => $config{wikiname},
    );

    IkiWiki::decode_form_utf8($form);
    IkiWiki::run_hooks(formbuilder_setup => sub {
            shift->(title => "comment", form => $form, cgi => $cgi,
                session => $session, buttons => \@buttons);
        });
    IkiWiki::decode_form_utf8($form);

    my $type = $form->param('type');
    if (defined $type && length $type && $IkiWiki::hooks{htmlize}{$type}) {
        $type = IkiWiki::possibly_foolish_untaint($type);
    }
    else {
        $type = $config{default_pageext};
    }
    my @page_types;
    if (exists $IkiWiki::hooks{htmlize}) {
        @page_types = grep { ! /^_/ } keys %{$IkiWiki::hooks{htmlize}};
    }

    $form->field(name => 'do', type => 'hidden');
    $form->field(name => 'sid', type => 'hidden', value => $session->id,
        force => 1);
    $form->field(name => 'page', type => 'hidden');
    $form->field(name => 'subject', type => 'text', size => 72);
    $form->field(name => 'editcontent', type => 'textarea', rows => 10);
    $form->field(name => "type", value => $type, force => 1,
        type => 'select', options => \@page_types);

    $form->tmpl_param(username => $session->param('name'));

    if ($config{comments_allowauthor} and
        ! defined $session->param('name')) {
        $form->tmpl_param(allowauthor => 1);
        $form->field(name => 'author', type => 'text', size => '40');
        $form->field(name => 'url', type => 'text', size => '40');
    }
    else {
        $form->tmpl_param(allowauthor => 0);
        $form->field(name => 'author', type => 'hidden', value => '',
            force => 1);
        $form->field(name => 'url', type => 'hidden', value => '',
            force => 1);
    }

    # The untaint is OK (as in editpage) because we're about to pass
    # it to file_pruned anyway
    my $page = $form->field('page');
    $page = IkiWiki::possibly_foolish_untaint($page);
    if (! defined $page || ! length $page ||
        IkiWiki::file_pruned($page, $config{srcdir})) {
        error(gettext("bad page name"));
    }

    # FIXME: is this right? Or should we be using the candidate subpage
    # (whatever that might mean) as the base URL?
    my $baseurl = urlto($page, undef, 1);

    $form->title(sprintf(gettext("commenting on %s"),
            IkiWiki::pagetitle($page)));

    $form->tmpl_param('helponformattinglink',
        htmllink($page, $page, 'ikiwiki/formatting',
            noimageinline => 1,
            linktext => 'FormattingHelp'),
            allowdirectives => $config{allow_directives});

    if ($form->submitted eq CANCEL) {
        # bounce back to the page they wanted to comment on, and exit.
        # CANCEL need not be considered in future
        IkiWiki::redirect($cgi, urlto($page, undef, 1));
        exit;
    }

    if (not exists $pagesources{$page}) {
        error(sprintf(gettext(
            "page '%s' doesn't exist, so you can't comment"),
            $page));
    }

    if (pagespec_match($page, $config{comments_closed_pagespec},
        location => $page)) {
        error(sprintf(gettext(
            "comments on page '%s' are closed"),
            $page));
    }

    # Set a flag to indicate that we're posting a comment,
    # so that postcomment() can tell it should match.
    $postcomment=1;
    IkiWiki::check_canedit($page, $cgi, $session);
    $postcomment=0;

    # FIXME: rather a simplistic way to make the comments...
    my $i = 0;
    my $file;
    my $location;
    do {
        $i++;
        $location = "$page/$config{comments_pagename}$i";
    } while (-e "$config{srcdir}/$location._comment");

    my $content = "[[!_comment format=$type\n";

    # FIXME: handling of double quotes probably wrong?
    if (defined $session->param('name')) {
        my $username = $session->param('name');
        $username =~ s/"/&quot;/g;
        $content .= " username=\"$username\"\n";
    }
    elsif (defined $ENV{REMOTE_ADDR}) {
        my $ip = $ENV{REMOTE_ADDR};
        if ($ip =~ m/^([.0-9]+)$/) {
            $content .= " ip=\"$1\"\n";
        }
    }

    if ($config{comments_allowauthor}) {
        my $author = $form->field('author');
        if (length $author) {
            $author =~ s/"/&quot;/g;
            $content .= " claimedauthor=\"$author\"\n";
        }
        my $url = $form->field('url');
        if (length $url) {
            $url =~ s/"/&quot;/g;
            $content .= " url=\"$url\"\n";
        }
    }

    my $subject = $form->field('subject');
    if (length $subject) {
        $subject =~ s/"/&quot;/g;
        $content .= " subject=\"$subject\"\n";
    }

    $content .= " date=\"" . decode_utf8(strftime('%Y-%m-%dT%H:%M:%SZ', gmtime)) . "\"\n";

    my $editcontent = $form->field('editcontent') || '';
    $editcontent =~ s/\r\n/\n/g;
    $editcontent =~ s/\r/\n/g;
    $editcontent =~ s/"/\\"/g;
    $content .= " content=\"\"\"\n$editcontent\n\"\"\"]]\n";

    # This is essentially a simplified version of editpage:
    # - the user does not control the page that's created, only the parent
    # - it's always a create operation, never an edit
    # - this means that conflicts should never happen
    # - this means that if they do, rocks fall and everyone dies

    if ($form->submitted eq PREVIEW) {
        my $preview = IkiWiki::htmlize($location, $page, '_comment',
                IkiWiki::linkify($page, $page,
                    IkiWiki::preprocess($page, $page,
                        IkiWiki::filter($location,
                            $page, $content),
                        0, 1)));
        IkiWiki::run_hooks(format => sub {
                $preview = shift->(page => $page,
                    content => $preview);
            });

        my $template = template("comments_display.tmpl");
        $template->param(content => $preview);
        $template->param(title => $form->field('subject'));
        $template->param(ctime => displaytime(time));

        $form->tmpl_param(page_preview => $template->output);
    }
    else {
        $form->tmpl_param(page_preview => "");
    }

    if ($form->submitted eq POST_COMMENT && $form->validate) {
        my $file = "$location._comment";

        IkiWiki::checksessionexpiry($cgi, $session);

        # FIXME: could probably do some sort of graceful retry
        # on error? Would require significant unwinding though
        writefile($file, $config{srcdir}, $content);

        my $conflict;

        if ($config{rcs} and $config{comments_commit}) {
            my $message = gettext("Added a comment");
            if (defined $form->field('subject') &&
                length $form->field('subject')) {
                $message = sprintf(
                    gettext("Added a comment: %s"),
                    $form->field('subject'));
            }

            IkiWiki::rcs_add($file);
            IkiWiki::disable_commit_hook();
            $conflict = IkiWiki::rcs_commit_staged($message,
                $session->param('name'), $ENV{REMOTE_ADDR});
            IkiWiki::enable_commit_hook();
            IkiWiki::rcs_update();
        }

        # Now we need a refresh
        require IkiWiki::Render;
        IkiWiki::refresh();
        IkiWiki::saveindex();

        # this should never happen, unless a committer deliberately
        # breaks it or something
        error($conflict) if defined $conflict;

        # Bounce back to where we were, but defeat broken caches
        my $anticache = "?updated=$page/$config{comments_pagename}$i";
        IkiWiki::redirect($cgi, urlto($page, undef, 1).$anticache);
    }
    else {
        IkiWiki::showform ($form, \@buttons, $session, $cgi,
            forcebaseurl => $baseurl);
    }

    exit;
}

sub pagetemplate (@) {
    my %params = @_;

    my $page = $params{page};
    my $template = $params{template};

    if ($template->query(name => 'comments')) {
        my $comments = undef;

        my $open = 0;
        my $shown = 0;
        if (pagespec_match($page,
                $config{comments_pagespec},
                location => $page)) {
            $shown = 1;
            $open = length $config{cgiurl} > 0;
        }

        if (pagespec_match($page,
                "$config{comments_closed_pagespec} or */$config{comments_pagename}*",
                location => $page)) {
            $shown = 0;
            $open = 0;
        }

        if ($shown) {
            $comments = IkiWiki::preprocess_inline(
                pages => "internal($page/$config{comments_pagename}*)",
                template => 'comments_display',
                show => 0,
                reverse => 'yes',
                page => $page,
                destpage => $params{destpage},
                feedfile => 'comments',
                emptyfeeds => 'no',
            );
        }

        if (defined $comments && length $comments) {
            $template->param(comments => $comments);
        }

        if ($open) {
            my $commenturl = IkiWiki::cgiurl(do => 'comment',
                page => $page);
            $template->param(commenturl => $commenturl);
        }
    }

    if ($template->query(name => 'commentuser')) {
        $template->param(commentuser =>
            $pagestate{$page}{comments}{commentuser});
    }

    if ($template->query(name => 'commentip')) {
        $template->param(commentip =>
            $pagestate{$page}{comments}{commentip});
    }

    if ($template->query(name => 'commentauthor')) {
        $template->param(commentauthor =>
            $pagestate{$page}{comments}{commentauthor});
    }

    if ($template->query(name => 'commentauthorurl')) {
        $template->param(commentauthorurl =>
            $pagestate{$page}{comments}{commentauthorurl});
    }
}

package IkiWiki::PageSpec;

sub match_postcomment ($$;@) {
    my $page = shift;
    my $glob = shift;

    if (! $postcomment) {
        return IkiWiki::FailReason->new("not posting a comment");
    }
    return match_glob($page, $glob);
}

1