#!/usr/bin/perl
package IkiWiki::Plugin::recentchanges;

use warnings;
use strict;
use IkiWiki 3.00;
use Encode;
use HTML::Entities;

sub import {
	hook(type => "getsetup", id => "recentchanges", call => \&getsetup);
	hook(type => "checkconfig", id => "recentchanges", call => \&checkconfig);
	hook(type => "refresh", id => "recentchanges", call => \&refresh);
	hook(type => "pagetemplate", id => "recentchanges", call => \&pagetemplate);
	hook(type => "htmlize", id => "_change", call => \&htmlize);
	hook(type => "sessioncgi", id => "recentchanges", call => \&sessioncgi);
	# Load goto to fix up links from recentchanges
	IkiWiki::loadplugin("goto");
}

sub getsetup () {
	return
		plugin => {
			safe => 1,
			rebuild => 1,
		},
		recentchangespage => {
			type => "string",
			example => "recentchanges",
			description => "name of the recentchanges page",
			safe => 1,
			rebuild => 1,
		},
		recentchangesnum => {
			type => "integer",
			example => 100,
			description => "number of changes to track",
			safe => 1,
			rebuild => 0,
		},
}

sub checkconfig () {
	$config{recentchangespage}='recentchanges' unless defined $config{recentchangespage};
	$config{recentchangesnum}=100 unless defined $config{recentchangesnum};
}

sub refresh ($) {
	my %seen;

	# add new changes
	foreach my $change (IkiWiki::rcs_recentchanges($config{recentchangesnum})) {
		$seen{store($change, $config{recentchangespage})}=1;
	}
	
	# delete old and excess changes
	foreach my $page (keys %pagesources) {
		if ($pagesources{$page} =~ /\._change$/ && ! $seen{$page}) {
			unlink($config{srcdir}.'/'.$pagesources{$page});
		}
	}
}

sub confirmation_form {
    my ($q, $session, $rev) = @_;

    eval q{use CGI::FormBuilder};
    error($@) if $@;
    my $f = CGI::FormBuilder->new(
		name => "revert",
		header => 0,
		charset => "utf-8",
		method => 'POST',
		javascript => 0,
		params => $q,
		action => $config{cgiurl},
		stylesheet => 1,
                template => { template('revert.tmpl') },
	);

    $f->field(name => "sid", type => "hidden", value => $session->id,
              force => 1);
    $f->field(name => "do", type => "hidden", value => "revert", force => 1);

    return $f, ["Revert", "Cancel"];
}

sub sessioncgi ($$) {
    my ($q, $session) = @_;
    my $do = $q->param('do');
    my $rev = $q->param('rev');

    return unless $do eq 'revert' && $rev;

    IkiWiki::rcs_preprevert(cgi => $q, session => $session, rev => $rev);

    my ($form, $buttons) = confirmation_form($q, $session);
    IkiWiki::decode_form_utf8($form);

    if($form->submitted eq 'Revert' && $form->validate) {
        IkiWiki::checksessionexpiry($q, $session, $q->param('sid'));

        IkiWiki::disable_commit_hook();
        my $r = IkiWiki::rcs_revert(
                         session => $session,
                         rev => $rev);
        IkiWiki::enable_commit_hook();

        if($r) {
            die "Revert '$rev' failed.";
        } else {
            require IkiWiki::Render;
            IkiWiki::refresh();
            IkiWiki::saveindex();
        }
    } else {
        $form->title(sprintf(gettext("confirm reversion of %s"), $rev));
        my $patch_contents = IkiWiki::rcs_showpatch(rev => $rev);
        $form->tmpl_param(patch_contents => encode_entities($patch_contents));
        $form->field(name => "rev", type => "hidden", value => $rev, force => 1);
        IkiWiki::showform($form, $buttons, $session, $q);
        exit 0;
    }

    IkiWiki::redirect($q, urlto($config{recentchangespage}, ''));
    exit 0;
}

# Enable the recentchanges link.
sub pagetemplate (@) {
	my %params=@_;
	my $template=$params{template};
	my $page=$params{page};

	if (defined $config{recentchangespage} && $config{rcs} &&
	    $template->query(name => "recentchangesurl") &&
	    $page ne $config{recentchangespage}) {
		$template->param(recentchangesurl => urlto($config{recentchangespage}, $page));
		$template->param(have_actions => 1);
	}
}

# Pages with extension _change have plain html markup, pass through.
sub htmlize (@) {
	my %params=@_;
	return $params{content};
}

sub store ($$$) {
	my $change=shift;

	my $page="$config{recentchangespage}/change_".titlepage($change->{rev});

	# Optimisation to avoid re-writing pages. Assumes commits never
	# change (or that any changes are not important).
	return $page if exists $pagesources{$page} && ! $config{rebuild};

	# Limit pages to first 10, and add links to the changed pages.
	my $is_excess = exists $change->{pages}[10];
	delete @{$change->{pages}}[10 .. @{$change->{pages}}] if $is_excess;
	$change->{pages} = [
		map {
			if (length $config{cgiurl}) {
				$_->{link} = "<a href=\"".
					IkiWiki::cgiurl(
						do => "goto",
						page => $_->{page}
					).
					"\" rel=\"nofollow\">".
					pagetitle($_->{page}).
					"</a>"
			}
			else {
				$_->{link} = pagetitle($_->{page});
			}
			$_->{baseurl}="$config{url}/" if length $config{url};

			$_;
		} @{$change->{pages}}
	];
	push @{$change->{pages}}, { link => '...' } if $is_excess;

        if (length $config{cgiurl}) {
            $change->{reverturl} = IkiWiki::cgiurl(
                  do => "revert",
                  rev => $change->{rev}
                );
        }

	$change->{author}=$change->{user};
	my $oiduser=eval { IkiWiki::openiduser($change->{user}) };
	if (defined $oiduser) {
		$change->{authorurl}=$change->{user};
		$change->{user}=defined $change->{nickname} ? $change->{nickname} : $oiduser;
	}
	elsif (length $config{cgiurl}) {
		$change->{authorurl} = IkiWiki::cgiurl(
			do => "goto",
			page => IkiWiki::userpage($change->{author}),
		);
	}

	if (ref $change->{message}) {
		foreach my $field (@{$change->{message}}) {
			if (exists $field->{line}) {
				# escape html
				$field->{line} = encode_entities($field->{line});
				# escape links and preprocessor stuff
				$field->{line} = encode_entities($field->{line}, '\[\]');
			}
		}
	}

	# Fill out a template with the change info.
	my $template=template("change.tmpl", blind_cache => 1);
	$template->param(
		%$change,
		commitdate => displaytime($change->{when}, "%X %x"),
		wikiname => $config{wikiname},
	);
	
	$template->param(permalink => "$config{url}/$config{recentchangespage}/#change-".titlepage($change->{rev}))
		if exists $config{url};
	
	IkiWiki::run_hooks(pagetemplate => sub {
		shift->(page => $page, destpage => $page,
			template => $template, rev => $change->{rev});
	});

	my $file=$page."._change";
	writefile($file, $config{srcdir}, $template->output);
	utime $change->{when}, $change->{when}, "$config{srcdir}/$file";

	return $page;
}

1