#!/usr/bin/perl -w

use IO::File;
use Data::Dumper;

$etcfile= "/etc/bind/chiark-conf-gen.zones";
$where= '<built-in>';

$mode= '';
$verbosity= 1;
$fromroot= 0;

while (@ARGV && $ARGV[0] =~ m/^\-/) {
    $_= shift @ARGV;
    if (s/^\-\-//) {
	last if m/^$/;
	if (m/^quiet$/) { $verbosity=0; }
	elsif (m/^verbose$/) { $verbosity=2; }
	elsif (m/^root$/) { $fromroot=1; }
	elsif (m/^(yes|no|force)$/) { m/^./; $mode= $&; }
	elsif (m/^config$/) { $etcfile= loarg(); $where= '--config option'; }
	else { usageerr("unknown option --$_"); }
    } else {
	s/^\-//;
	last if m/^$/;
	while (m/^./) {
	    if (s/^[ynf]//) { $mode=$&; }
	    elsif (s/^r//) { $fromroot=1; }
	    elsif (s/^v//) { $verbosity=2; }
	    elsif (s/^q//) { $verbosity=0; }
	    elsif (s/^C//) { $etcfile= soarg(); $where= '-C option'; }
	    else { usageerr("unknown option -$&"); }
	}
    }
}

sub loarg() { usageerr("missing option value") if !@ARGV; return shift @ARGV; }
sub soarg() { my ($rv); $rv=$_; $_=''; return length $rv ? $rv : loarg(); }

usageerr("must specify either -f|-y|-n or zones (and not both)")
    if !!$mode == !!@ARGV;

sub usageerr ($) {
    die
"$_[0]
usage: named-conf-regen [-rvq] -f|-y|-n|<zone>...\n".
"operation modes:\n".
" -f --force   install without checking\n".
" -y --yes     check and install\n".
" -n --no      check only\n".
"additional options:\n".
" -r --root    check all the way back to the root\n".
" -q --quiet   no output for OK zones\n".
" -v --verbose extra verbose\n";
}

cfg_fail("config filename $etcfile should have been absolute path of a file")
    unless $etcfile =~ m,^/, && $etcfile !~ m,/$,;

$default_dir= $etcfile;
$default_dir =~ s,/[^/]+$,,;

$slave_dir= 'slave';
$slave_prefix= '';
$slave_suffix= '';
@self_ns= @self_soa= ();
%zone_cfg= ();
@zone_cfg_list= ();
$output= '';
$default_output= '';
%output_contents= ();

read_config($etcfile);

print Dumper(@zone_cfg_list), Dumper(%zone_cfg);

sub cfg_fail ($) { die "$0: $where:\n $_[0]\n"; }

sub read_config ($) {
    my ($if) = @_;
    my ($fh,$z,@self, $dir,$prefix,$suffix,$lprefix,$lsuffix);
    local ($_,$1,$2,$3);

    $fh= new IO::File $if,'r' or cfg_fail("open $if:\n $!");
    for (;;) {
	if (!defined($_= <$fh>)) {
	    cfg_fail("read config file $if:\n $!") if $fh->error();
	    last;
	}
	$where= "$if:$.";
	s/^\s+//; chomp; s/\s+$//;
	next if m/^\#/;
	last if m/^end$/;
	next unless m/\S/;
	if (m/^self(\-ns|\-soa|)\s+(\S.*\S)/) {
	    @self= split /\s+/, $2;
	    @self_ns= @self if $1 ne '-soa';
	    @self_soa= @self if $1 ne '-ns';
	} elsif (m/^primary\-dir\s+(\S+)((?:\s+(\S+))??:\s+(\S+))?$/) {
	    ($dir, $prefix, $suffix) = (qualify($1),$2,$3);
	    $suffix= '_db' if !length $suffix;
	    opendir D, $dir or cfg_fail("open primary-dir $dir:\n $!");
	    $lprefix= length $prefix; $lsuffix= length $suffix;
	    while ($!=0, $_= readdir D) {
		next if m/^\./ && !$lprefix;
		next unless length > $lprefix+$lsuffix;
		next unless substr($_,0,$lprefix) eq $prefix;
		next unless substr($_,length($_)-$lsuffix) eq $suffix;
		$z= substr($_,$lprefix,length($_)-($lprefix+$lsuffix));
		zone_conf($z,'primary',"$dir/$_");
	    }
	    $! and cfg_fail("read primary-dir $dir:\n $!");
	    closedir D or cfg_fail("close primary-dir $dir:\n $!");
	} elsif (m/^primary\s+(\S+)\s+(\S+)$/) {
	    zone_conf($1,'primary',qualify($2));
	} elsif (m/^secondary\s+(\S+)\s+([0-9.\t]+)$/) {
	    zone_conf($1,'secondary','',$2);
	} elsif (m/^stealth\s+(\S+)\s+([0-9. \t]+)$/) {
	    zone_conf($1,'stealth','',split /\s+/, $2);
	} elsif (m/^slave\-dir\s+(\S+)((?:\s+(\S+))??:\s+(\S+))?$/) {
	    ($slave_dir, $slave_prefix, $slave_suffix) = (qualify($1),$2,$3);
	} elsif (m/^output\s+bind8\+(\S+)$/) {
	    cfg_fail("default output may not apply to only some zones")
		if @zone_cfg_list && length $default_output;
	    set_output(qualify($1));
	} elsif (m/^include\s+(\S+)$/) {
	    read_config($1);
	} else {
	    cfg_fail("unknown configuration directive".
		     " or incorrect syntax or arguments");
	}
    }
    $fh->close or cfg_fail("close config file $if:\n $!");
}

sub qualify ($) {
    my ($i) = @_;
    $i= "$default_dir/$i" unless $i =~ m,^/,;
}

sub zone_conf ($$@) {
    my ($zone,$style,$file,@servers) = @_;
    $file= qualify("$slave_dir/$slave_prefix".$zone.$slave_suffix)
	unless length $file;
    if (!length $output) {
	$default_output= qualify('chiark-conf-gen.bind8')
	    unless length $default_output;
	set_output($default_output);
    }
    cfg_fail("redefined zone $zone") if exists $zone_cfg{$zone};
    $zone_cfg{$zone}{'file'}= $file;
    $zone_cfg{$zone}{'style'}= $style;
    $zone_cfg{$zone}{'servers'}= @servers;
    $zone_cfg{$zone}{'output'}= $output;
    push @zone_cfg_list, $zone;
}

sub set_output($) {
    my ($newout) = @_;
    $output= $newout;
    $output_contents{$output}= '';
}

__DATA__



sub lookup ($$) {
    my ($type,$domain) = @_;
    my ($c,@result);
    defined($c=open ADH, "-|") or die "$0: fork adnshost:\n $!\n";
    if (!$c) {
	exec 'adnshost','+Do','+Dt','+Dc','-Cf',"-t$type",
	     '-',"$domain.";
	die "$0: exec adnshost:\n $!\n";
    }
    @result= <ADH>;
    chomp @result;
    $!=0; close ADH;
    die "$0: lookup -t$type $domain failed $? $!\n" if $? or $!;
    return @result;
}

sub lookup1 ($$) {
    my ($type,$domain) = @_;
    my (@result)= lookup($type,$domain);
    @result==1 or die "$0: lookup -t$type $domain gave more than one RR\n";
    return $result[0];
}

sub check () {
    return unless $check;
    eval {
	$soa= lookup1('soa',$zone);
	$soa_origin=$soa; $soa_origin =~ s/ .*//;
	$soa_origin_addr= lookup1('a',$soa_origin);

	@zone_ns= lookup('ns-',$zone);

	@ok_sources= ($soa_origin_addr);
	$ok_sources_descr= "SOA ORIGIN $soa_origin [$soa_origin_addr]";

	if ($style eq 'unoff' || $style eq 'backup') {
	    for $zone_ns (@zone_ns) {
		@zone_ns_addrs= lookup('a',$zone_ns);
		push @ok_sources, @zone_ns_addrs;
		$ok_sources_descr.= ", NS $zone_ns [@zone_ns_addrs]";
	    }
	}

	for $server (@servers) {
	    grep { $server eq $_ } @ok_sources
		or warn "secondarying from $server which is not ".
		        "$ok_sources_desc\n";
	}

	if ($style eq 'secondary') {
	    grep { $zone_ns=$_, grep { $myname eq $_ } @mynames } @zone_n
		or warn "supposedly published secondary but we ".
		        "(@mynames) are not published ($@zone_ns)\n";
	}
    }
    check_after_eval();
    

			 
#	$superzone= $zone; $superzone =~ s/^[^\.]+\.//;
#	@super_ns= lookup('ns-',$zone);
    }

    eval {

	for $super_ns (@super_ns) {
	    @deleg_ns= ();
	    open DIG, "dig @$super_ns. -t ns +norecurse $zone."
		or die "$0: fork for dig:\n $!\n";
	    while (<DIG>) {
		

	    split /\n/, lookup("
	
		case "$style" in
		secondary|backup)
			if [ $meadvert = 0 ]
			then
				warning "$myname unlisted NS $nsnames"
			fi
			;;
		unoff)
			if $meadvert = 0
			then
				warning "$myname advertised NS $nsnames"
			fi
			;;
		esac

		addrs=''
		for ns in $names
		do
			set -e; a="`host -t a \"$ns\".`"; set +e
			taddrs="`echo \" $a\" | expand | sed -n '
				 1s/^ //
				s/^[^ ][^ ]*  *A  *\([0-9][.0-9]*\)/\1/p
			'`"
			equlines "A $ns" "$a" "$taddrs"
			addrs="$addrs $taddrs"
		done
	fi

	cat <<END
zone "$zone" {
	type slave;
	file "$file";
	masters {
END
	for server in $servers
	do
		echo "		$server;"
		if $check
		then
			notfound=1
			for addr in $addrs
			do
				if [ "x$addr" = "x$server" ]
				then
					notfound=0
				fi
			done
			if $notfound
			then
 warning "server $server? but $rectype $names" $addrs
			fi
		fi
	done
	cat <<END
	};
};
END
	hostfirstwarn=1
	if $hostdelg
	then
		checkhostout -C
	fi
	if $hostzone
	then
		checkhostout -val localhost
	fi
done
endfile

    
chdir "$base/primary" or die "$0: chdir $base/primary:\n $!";
beginfile('primary.zones');

for $f (<*_db>) {
    $zone= $f; $zone =~ s/_db$//;
    

for f in $zones
do
	zone="`echo $f | sed -e 's/_db$//'`"
	cat <<END
zone "$zone" {
	type master;
	file "primary/$f";
};
END
done
endfile


    
sub beginfile ($) {
    $currentfile= $_[0];
    $currentfile_opened= $install ? "$conf/$currentfile.new" : "/dev/null";
    open CFF, "> $toopen" or die "$0: begin $currentfile_opened:\n $!\n";
}

endfile () {
    close CFF or die "$0: close $currentfile_opened:\n $!\n";
    push @files, $currentfile;
}

sub installfiles () {
    return unless $install;
    chdir $conf or die "$0: chdir $conf:\n $!\n";
    for $f (@files) {
	rename "$f.new", $f or die "$0: install new $f:\n $!\n";
    }
}

warning () {
	echo >&2 "$zone $style: $*"
	warnings=$[$warnings+1]
}

equlines () {
	if [ "x`echo \" $2\" | wc -l`" != "x`echo \" $3\" | wc -l`" ]
	then
		warning "$1 >$2|$3<"
	fi
}

checkhostout () {
	set +e
	hostout="`host $1 \"$zone\" 2>&1 >/dev/null $2 | egrep -v \
'^ \!\!\! .* SOA primary .* is not advertised via NS$'`"
	set -e
	if [ "x$hostout" = x ]; then return; fi
	if $hostfirstwarn
	then
		warning "warnings from host:"
		hostfirstwarn=0
	fi
	echo >&2 "$hostout"
}

progress () {
	if $progress
	then
		echo -n "$zone $style                    " >&2
		echo -ne '\r' >&2
	fi
}

myname=''

if [ $warnings != 0 ]
then
	echo >&2 "$warnings warnings                                        "
fi

installfiles