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 => "checkconfig", id => 'comments',  call => \&checkconfig);
    hook(type => "getsetup", id => 'comments',  call => \&getsetup);
    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");
    IkiWiki::loadplugin("mdwn");
} # }}}

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

sub getsetup () { #{{{
    return
        plugin => {
            safe => 1,
            rebuild => 1,
        },
        # Pages where comments are shown, but new comments are not
        # allowed, will show "Comments are closed".
        comments_shown_pagespec => {
            type => 'pagespec',
            example => 'blog/*',
            default => '',
            description => 'PageSpec for pages where comments will be shown inline',
            link => 'ikiwiki/PageSpec',
            safe => 1,
            rebuild => 1,
        },
        comments_open_pagespec => {
            type => 'pagespec',
            example => 'blog/* and created_after(close_old_comments)',
            default => '',
            description => 'PageSpec for pages where new comments can be posted',
            link => 'ikiwiki/PageSpec',
            safe => 1,
            rebuild => 1,
        },
        comments_pagename => {
            type => 'string',
            example => 'comment_',
            default => 'comment_',
            description => 'Base name for comments, e.g. "comment_" for pages like "sandbox/comment_12"',
            safe => 0, # manual page moving will required
            rebuild => undef,
        },
        comments_allowdirectives => {
            type => 'boolean',
            default => 0,
            example => 0,
            description => 'Allow directives in newly posted comments?',
            safe => 1,
            rebuild => 0,
        },
        comments_commit => {
            type => 'boolean',
            example => 1,
            default => 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_pagename} = 'comment_'
        unless defined $config{comments_pagename};
} #}}}

# 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;
} # }}}

# 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);
    }
} # }}}

# 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 = $config{comments_allowdirectives};
    my $commit_comments = $config{comments_commit};
    my $comments_pagename = $config{comments_pagename};

    # 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 => $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 (not pagespec_match($page, $config{comments_open_pagespec},
        location => $page)) {
        error(sprintf(gettext(
            "comments on page '%s' are closed"),
            $page));
    }

    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&#91;&#91;!/g;

        # don't allow [[ unless it begins an old-style
        # wikilink, if prefix_directives is off
        $body =~ s/(^|[^\\])\[\[(?![^\n\s\]+]\]\])/$1&#91;&#91;!/g
            unless $config{prefix_directives};
    }

    # 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;
    my $location;
    do {
        $i++;
        $location = "$page/${comments_pagename}${i}";
    } while (-e "$config{srcdir}/$location._comment");

    my $anchor = "${comments_pagename}${i}";

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

    # 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);
    $content_tmpl->param(anchor => "$anchor");
    $content_tmpl->param(permalink => "$baseurl#$anchor");
    $content_tmpl->param(date => IkiWiki::formattime(time, "%X %x"));

    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) {
        my $preview = IkiWiki::htmlize($location, $page, 'mdwn',
                IkiWiki::linkify($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));
        $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) {
        my $file = "$location._comment";

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

        # 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 $commit_comments) {
            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/${comments_pagename}${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 $comments_pagename = $config{comments_pagename};

        my $open = 0;
        my $shown = pagespec_match($page,
            $config{comments_shown_pagespec},
            location => $page);

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

        if (length $config{cgiurl}) {
            $open = pagespec_match($page,
                $config{comments_open_pagespec},
                location => $page);
        }

        if ($shown) {
            eval q{use IkiWiki::Plugin::inline};
            error($@) if $@;

            my @args = (
                pages => "internal($page/${comments_pagename}*)",
                template => 'comments_display',
                show => 0,
                reverse => 'yes',
                page => $page,
                destpage => $params{destpage},
            );
            $comments = IkiWiki::preprocess_inline(@args);
        }

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

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

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);
}

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