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

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

sub htmlize { # {{{
    eval { use IkiWiki::Plugin::mdwn; };
    error($@) if ($@);
    return IkiWiki::Plugin::mdwn::htmlize(@_)
} # }}}

sub getsetup () { #{{{
    return
        plugin => {
            safe => 1,
            rebuild => undef,
        },
} #}}}

# Somewhat based on IkiWiki::Plugin::inline blog posting support
sub preprocess (@) { #{{{
    my %params=@_;

    unless (length $config{cgiurl}) {
        error(gettext("[[!comments plugin requires CGI enabled]]"));
    }

    my $page = $params{page};
    $pagestate{$page}{comments}{comments} = defined $params{closed}
        ? (not IkiWiki::yesno($params{closed}))
        : 1;
    $pagestate{$page}{comments}{allowhtml} = IkiWiki::yesno($params{allowhtml});
    $pagestate{$page}{comments}{allowdirectives} = IkiWiki::yesno($params{allowdirectives});
    $pagestate{$page}{comments}{commit} = defined $params{commit}
        ? IkiWiki::yesno($params{commit})
        : 1;

    my $formtemplate = IkiWiki::template("comments_embed.tmpl",
        blind_cache => 1);
    $formtemplate->param(cgiurl => $config{cgiurl});
    $formtemplate->param(page => $params{page});

    if (not $pagestate{$page}{comments}{comments}) {
        $formtemplate->param("disabled" =>
            gettext('comments are closed'));
    }
    elsif ($params{preview}) {
        $formtemplate->param("disabled" =>
            gettext('not available during Preview'));
    }

    debug("page $params{page} => destpage $params{destpage}");

    my $posts = '';
    unless (defined $params{inline} && !IkiWiki::yesno($params{inline})) {
        eval { use IkiWiki::Plugin::inline; };
        error($@) if ($@);
        my @args = (
            pages => "internal($params{page}/_comment_*)",
            template => "comments_display",
            show => 0,
            reverse => "yes",
            # special stuff passed through
            page => $params{page},
            destpage => $params{destpage},
            preview => $params{preview},
        );
        push @args, atom => $params{atom} if defined $params{atom};
        push @args, rss => $params{rss} if defined $params{rss};
        push @args, feeds => $params{feeds} if defined $params{feeds};
        push @args, feedshow => $params{feedshow} if defined $params{feedshow};
        push @args, timeformat => $params{timeformat} if defined $params{timeformat};
        push @args, feedonly => $params{feedonly} if defined $params{feedonly};
        $posts = "\n" . IkiWiki::preprocess_inline(@args);
    }

    return $formtemplate->output . $posts;
} # }}}

# FIXME: logic taken from editpage, should be common code?
sub getcgiuser ($) { # {{{
    my $session = shift;
    my $user = $session->param('name');
    $user = $ENV{REMOTE_ADDR} unless defined $user;
    debug("getcgiuser() -> $user");
    return $user;
} # }}}

# FIXME: logic adapted from recentchanges, should be common code?
sub linkuser ($) { # {{{
    my $user = shift;
    my $oiduser = eval { IkiWiki::openiduser($user) };

    if (defined $oiduser) {
        return ($user, $oiduser);
    }
    else {
        my $page = bestlink('', (length $config{userdir}
                ? "$config{userdir}/"
                : "").$user);
        return (urlto($page, undef, 1), $user);
    }
} # }}}

# FIXME: taken from IkiWiki::Plugin::editpage, should be common?
sub checksessionexpiry ($$) { # {{{
    my $session = shift;
    my $sid = shift;

    if (defined $session->param("name")) {
        if (! defined $sid || $sid ne $session->id) {
            error(gettext("Your login session has expired."));
        }
    }
} # }}}

# 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 body}],
        charset => 'utf-8',
        method => 'POST',
        required => [qw{body}],
        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);

    $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 => 'body', type => 'textarea', rows => 5,
        cols => 80);

    # 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"));
    }

    my $allow_directives = $pagestate{$page}{comments}{allowdirectives};
    my $allow_html = $pagestate{$page}{comments}{allowdirectives};
    my $commit_comments = defined $pagestate{$page}{comments}{commit}
        ? $pagestate{$page}{comments}{commit}
        : 1;

    # 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'),
            allowhtml => $allow_html,
            allowdirectives => $allow_directives);

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

    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;
    }

    IkiWiki::check_canedit($page . "[postcomment]", $cgi, $session);

    my ($authorurl, $author) = linkuser(getcgiuser($session));

    my $body = $form->field('body') || '';
    $body =~ s/\r\n/\n/g;
    $body =~ s/\r/\n/g;
    $body = "\n" if $body !~ /\n$/;

    unless ($allow_directives) {
        # don't allow new-style directives at all
        $body =~ s/(^|[^\\])\[\[!/$1\\[[!/g;

        # don't allow [[ unless it begins an old-style
        # wikilink, if prefix_directives is off
        $body =~ s/(^|[^\\])\[\[(?![^\n\s\]+]\]\])/$1\\[[!/g
            unless $config{prefix_directives};
    }

    unless ($allow_html) {
        $body =~ s/&(\w|#)/&amp;$1/g;
        $body =~ s/</&lt;/g;
        $body =~ s/>/&gt;/g;
    }

    # In this template, the [[!meta]] directives should stay at the end,
    # so that they will override anything the user specifies. (For
    # instance, [[!meta author="I can fake the author"]]...)
    my $content_tmpl = template('comments_comment.tmpl');
    $content_tmpl->param(author => $author);
    $content_tmpl->param(authorurl => $authorurl);
    $content_tmpl->param(subject => $form->field('subject'));
    $content_tmpl->param(body => $body);

    my $content = $content_tmpl->output;

    # 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) {
        # $fake is a location that has the same number of slashes
        # as the eventual location of this comment.
        my $fake = "$page/_comments_hypothetical";
        my $preview = IkiWiki::htmlize($fake, $page, 'mdwn',
                IkiWiki::linkify($page, $page,
                    IkiWiki::preprocess($page, $page,
                        IkiWiki::filter($fake, $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));
        $template->param(author => $author);
        $template->param(authorurl => $authorurl);

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

    if ($form->submitted eq POST_COMMENT && $form->validate) {
        # Let's get posting. We don't check_canedit here because
        # that somewhat defeats the point of this plugin.

        checksessionexpiry($session, $cgi->param('sid'));

        # FIXME: check that the wiki is locked right now, because
        # if it's not, there are mad race conditions!

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

        # FIXME: could probably do some sort of graceful retry
        # if I could be bothered
        writefile($file, $config{srcdir}, $content);

        my $conflict;

        if ($config{rcs} and $commit_comments) {
            my $message = gettext("Added a comment");
            if (defined $form->field('subject') &&
                length $form->field('subject')) {
                $message .= ": ".$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/_comment_$i";
        IkiWiki::redirect($cgi, urlto($page, undef, 1).$anticache);
    }
    else {
        IkiWiki::showform ($form, \@buttons, $session, $cgi,
            forcebaseurl => $baseurl);
    }

    exit;
} #}}}

package IkiWiki::PageSpec;

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

    unless ($page =~ s/\[postcomment\]$//) {
        return IkiWiki::FailReason->new("not posting a comment");
    }
    return match_glob($page, $glob);
}

1