#!/usr/bin/perl -T

$ENV{PATH}="/usr/local/bin:/usr/bin:/bin";

use lib '.'; # For use without installation, removed by Makefile.

package IkiWiki;
use warnings;
use strict;
use Memoize;
use File::Spec;
use HTML::Template;
use Getopt::Long;

use vars qw{%config %links %oldlinks %oldpagemtime %renderedfiles %pagesources};

# Holds global config settings, also used by some modules.
our %config=( #{{{
	wiki_file_prune_regexp => qr{((^|/).svn/|\.\.|^\.|\/\.|\.html?$)},
	wiki_link_regexp => qr/\[\[([^\s\]]+)\]\]/,
	wiki_file_regexp => qr/(^[-A-Za-z0-9_.:\/+]+$)/,
	verbose => 0,
	wikiname => "wiki",
	default_pageext => ".mdwn",
	cgi => 0,
	svn => 1,
	url => '',
	cgiurl => '',
	historyurl => '',
	diffurl => '',
	anonok => 0,
	rebuild => 0,
	wrapper => undef,
	wrappermode => undef,
	srcdir => undef,
	destdir => undef,
	templatedir => "/usr/share/ikiwiki/templates",
	setup => undef,
	adminuser => undef,
); #}}}

GetOptions( #{{{
	"setup|s=s" => \$config{setup},
	"wikiname=s" => \$config{wikiname},
	"verbose|v!" => \$config{verbose},
	"rebuild!" => \$config{rebuild},
	"wrapper:s" => sub { $config{wrapper}=$_[1] ? $_[1] : "ikiwiki-wrap" },
	"wrappermode=i" => \$config{wrappermode},
	"svn!" => \$config{svn},
	"anonok!" => \$config{anonok},
	"cgi!" => \$config{cgi},
	"url=s" => \$config{url},
	"cgiurl=s" => \$config{cgiurl},
	"historyurl=s" => \$config{historyurl},
	"diffurl=s" => \$config{diffurl},
	"exclude=s@" => sub {
		$config{wiki_file_prune_regexp}=qr/$config{wiki_file_prune_regexp}|$_[1]/;
	},
	"adminuser=s@" => sub { push @{$config{adminuser}}, $_[1] },
	"templatedir=s" => sub { $config{templatedir}=possibly_foolish_untaint($_[1]) },
) || usage();

if (! $config{setup}) {
	usage() unless @ARGV == 2;
	$config{srcdir} = possibly_foolish_untaint(shift);
	$config{destdir} = possibly_foolish_untaint(shift);
	checkoptions();
}
#}}}

sub checkoptions { #{{{
	if ($config{cgi} && ! length $config{url}) {
		error("Must specify url to wiki with --url when using --cgi");
	}
	
	$config{wikistatedir}="$config{srcdir}/.ikiwiki"
		unless exists $config{wikistatedir};
	
	if ($config{svn}) {
		require IkiWiki::RCS::SVN;
		$config{rcs}=1;
	}
	else {
		require IkiWiki::RCS::Stub;
		$config{rcs}=0;
	}
} #}}}

sub usage { #{{{
	die "usage: ikiwiki [options] source dest\n";
} #}}}

sub error { #{{{
	if ($config{cgi}) {
		print "Content-type: text/html\n\n";
		print misctemplate("Error", "<p>Error: @_</p>");
	}
	die @_;
} #}}}

sub debug ($) { #{{{
	return unless $config{verbose};
	if (! $config{cgi}) {
		print "@_\n";
	}
	else {
		print STDERR "@_\n";
	}
} #}}}

sub possibly_foolish_untaint { #{{{
	my $tainted=shift;
	my ($untainted)=$tainted=~/(.*)/;
	return $untainted;
} #}}}

sub basename ($) { #{{{
	my $file=shift;

	$file=~s!.*/!!;
	return $file;
} #}}}

sub dirname ($) { #{{{
	my $file=shift;

	$file=~s!/?[^/]+$!!;
	return $file;
} #}}}

sub pagetype ($) { #{{{
	my $page=shift;
	
	if ($page =~ /\.mdwn$/) {
		return ".mdwn";
	}
	else {
		return "unknown";
	}
} #}}}

sub pagename ($) { #{{{
	my $file=shift;

	my $type=pagetype($file);
	my $page=$file;
	$page=~s/\Q$type\E*$// unless $type eq 'unknown';
	return $page;
} #}}}

sub htmlpage ($) { #{{{
	my $page=shift;

	return $page.".html";
} #}}}

sub readfile ($) { #{{{
	my $file=shift;

	if (-l $file) {
		error("cannot read a symlink ($file)");
	}
	
	local $/=undef;
	open (IN, "$file") || error("failed to read $file: $!");
	my $ret=<IN>;
	close IN;
	return $ret;
} #}}}

sub writefile ($$) { #{{{
	my $file=shift;
	my $content=shift;
	
	if (-l $file) {
		error("cannot write to a symlink ($file)");
	}

	my $dir=dirname($file);
	if (! -d $dir) {
		my $d="";
		foreach my $s (split(m!/+!, $dir)) {
			$d.="$s/";
			if (! -d $d) {
				mkdir($d) || error("failed to create directory $d: $!");
			}
		}
	}
	
	open (OUT, ">$file") || error("failed to write $file: $!");
	print OUT $content;
	close OUT;
} #}}}

sub bestlink ($$) { #{{{
	# Given a page and the text of a link on the page, determine which
	# existing page that link best points to. Prefers pages under a
	# subdirectory with the same name as the source page, failing that
	# goes down the directory tree to the base looking for matching
	# pages.
	my $page=shift;
	my $link=lc(shift);
	
	my $cwd=$page;
	do {
		my $l=$cwd;
		$l.="/" if length $l;
		$l.=$link;

		if (exists $links{$l}) {
			#debug("for $page, \"$link\", use $l");
			return $l;
		}
	} while $cwd=~s!/?[^/]+$!!;

	#print STDERR "warning: page $page, broken link: $link\n";
	return "";
} #}}}

sub isinlinableimage ($) { #{{{
	my $file=shift;
	
	$file=~/\.(png|gif|jpg|jpeg)$/;
} #}}}

sub htmllink { #{{{
	my $page=shift;
	my $link=shift;
	my $noimageinline=shift; # don't turn links into inline html images
	my $forcesubpage=shift; # force a link to a subpage

	my $bestlink;
	if (! $forcesubpage) {
		$bestlink=bestlink($page, $link);
	}
	else {
		$bestlink="$page/".lc($link);
	}

	return $link if length $bestlink && $page eq $bestlink;
	
	# TODO BUG: %renderedfiles may not have it, if the linked to page
	# was also added and isn't yet rendered! Note that this bug is
	# masked by the bug mentioned below that makes all new files
	# be rendered twice.
	if (! grep { $_ eq $bestlink } values %renderedfiles) {
		$bestlink=htmlpage($bestlink);
	}
	if (! grep { $_ eq $bestlink } values %renderedfiles) {
		return "<a href=\"$config{cgiurl}?do=create&page=$link&from=$page\">?</a>$link"
	}
	
	$bestlink=File::Spec->abs2rel($bestlink, dirname($page));
	
	if (! $noimageinline && isinlinableimage($bestlink)) {
		return "<img src=\"$bestlink\">";
	}
	return "<a href=\"$bestlink\">$link</a>";
} #}}}

sub indexlink () { #{{{
	return "<a href=\"$config{url}\">$config{wikiname}</a>";
} #}}}

sub lockwiki () { #{{{
	# Take an exclusive lock on the wiki to prevent multiple concurrent
	# run issues. The lock will be dropped on program exit.
	if (! -d $config{wikistatedir}) {
		mkdir($config{wikistatedir});
	}
	open(WIKILOCK, ">$config{wikistatedir}/lockfile") ||
		error ("cannot write to $config{wikistatedir}/lockfile: $!");
	if (! flock(WIKILOCK, 2 | 4)) {
		debug("wiki seems to be locked, waiting for lock");
		my $wait=600; # arbitrary, but don't hang forever to 
		              # prevent process pileup
		for (1..600) {
			return if flock(WIKILOCK, 2 | 4);
			sleep 1;
		}
		error("wiki is locked; waited $wait seconds without lock being freed (possible stuck process or stale lock?)");
	}
} #}}}

sub unlockwiki () { #{{{
	close WIKILOCK;
} #}}}

sub loadindex () { #{{{
	open (IN, "$config{wikistatedir}/index") || return;
	while (<IN>) {
		$_=possibly_foolish_untaint($_);
		chomp;
		my ($mtime, $file, $rendered, @links)=split(' ', $_);
		my $page=pagename($file);
		$pagesources{$page}=$file;
		$oldpagemtime{$page}=$mtime;
		$oldlinks{$page}=[@links];
		$links{$page}=[@links];
		$renderedfiles{$page}=$rendered;
	}
	close IN;
} #}}}

sub saveindex () { #{{{
	if (! -d $config{wikistatedir}) {
		mkdir($config{wikistatedir});
	}
	open (OUT, ">$config{wikistatedir}/index") || 
		error("cannot write to $config{wikistatedir}/index: $!");
	foreach my $page (keys %oldpagemtime) {
		print OUT "$oldpagemtime{$page} $pagesources{$page} $renderedfiles{$page} ".
	        	join(" ", @{$links{$page}})."\n"
				if $oldpagemtime{$page};
	}
	close OUT;
} #}}}

sub misctemplate ($$) { #{{{
	my $title=shift;
	my $pagebody=shift;
	
	my $template=HTML::Template->new(
		filename => "$config{templatedir}/misc.tmpl"
	);
	$template->param(
		title => $title,
		indexlink => indexlink(),
		wikiname => $config{wikiname},
		pagebody => $pagebody,
	);
	return $template->output;
}#}}}

sub userinfo_get ($$) { #{{{
	my $user=shift;
	my $field=shift;

	eval q{use Storable};
	my $userdata=eval{ Storable::lock_retrieve("$config{wikistatedir}/userdb") };
	if (! defined $userdata || ! ref $userdata || 
	    ! exists $userdata->{$user} || ! ref $userdata->{$user} ||
            ! exists $userdata->{$user}->{$field}) {
		return "";
	}
	return $userdata->{$user}->{$field};
} #}}}

sub userinfo_set ($$$) { #{{{
	my $user=shift;
	my $field=shift;
	my $value=shift;
	
	eval q{use Storable};
	my $userdata=eval{ Storable::lock_retrieve("$config{wikistatedir}/userdb") };
	if (! defined $userdata || ! ref $userdata || 
	    ! exists $userdata->{$user} || ! ref $userdata->{$user}) {
		return "";
	}
	
	$userdata->{$user}->{$field}=$value;
	my $oldmask=umask(077);
	my $ret=Storable::lock_store($userdata, "$config{wikistatedir}/userdb");
	umask($oldmask);
	return $ret;
} #}}}

sub userinfo_setall ($$) { #{{{
	my $user=shift;
	my $info=shift;
	
	eval q{use Storable};
	my $userdata=eval{ Storable::lock_retrieve("$config{wikistatedir}/userdb") };
	if (! defined $userdata || ! ref $userdata) {
		$userdata={};
	}
	$userdata->{$user}=$info;
	my $oldmask=umask(077);
	my $ret=Storable::lock_store($userdata, "$config{wikistatedir}/userdb");
	umask($oldmask);
	return $ret;
} #}}}

sub is_admin ($) { #{{{
	my $user_name=shift;

	return grep { $_ eq $user_name } @{$config{adminuser}};
} #}}}

sub glob_match ($$) { #{{{
	my $page=shift;
	my $glob=shift;

	# turn glob into safe regexp
	$glob=quotemeta($glob);
	$glob=~s/\\\*/.*/g;
	$glob=~s/\\\?/./g;
	$glob=~s!\\/!/!g;
	
	$page=~/^$glob$/i;
} #}}}

sub globlist_match ($$) { #{{{
	my $page=shift;
	my @globlist=split(" ", shift);

	# check any negated globs first
	foreach my $glob (@globlist) {
		return 0 if $glob=~/^!(.*)/ && glob_match($page, $1);
	}

	foreach my $glob (@globlist) {
		return 1 if glob_match($page, $glob);
	}
	
	return 0;
} #}}}

# main {{{
memoize('pagename');
memoize('bestlink');
if ($config{setup}) {
	require IkiWiki::Setup;
	setup();
}
lockwiki();
if ($config{wrapper}) {
	require IkiWiki::Wrapper;
	gen_wrapper();
	exit;
}
loadindex() unless $config{rebuild};
if ($config{cgi}) {
	require IkiWiki::CGI;
	cgi();
}
else {
	require IkiWiki::Render;
	rcs_update();
	refresh();
	saveindex();
}
#}}}