#!/usr/bin/perl -w
#
# Author: Holger Parplies, 09.01.09, GPL, uncommented, -*-quick-hack-*-

use strict;
use Data::Dumper;
use Getopt::Std;

$Data::Dumper::Terse = 1;

my %opts = (
	    f => undef,		# file name of config file to manipulate
           );

if (not getopts ('f:', \%opts) or @ARGV == 0 or not defined $opts {f}) {
  die "Usage: $0 -f host.pl VAR=VALUE ...\n";
}

our %Conf = ();
do $opts {f}
  or die "Can't do $opts{f}: $!\n";

foreach (@ARGV) {
  my ($var, $val) = m/^\s*(.*?)\s*(?:=\s*(.*?)\s*)?$/;
  my $confvar;
  if ($var =~ /^(.*)\{(.*)\}\[(.*)\]$/) {
    defined $val ? $Conf {$1} {$2} [$3] = $val
		 : splice @{$Conf {$1} {$2}}, $3, 1;
  } elsif ($var =~ /^(.*)\[(.*)\]$/) {
    defined $val ? $Conf {$1} [$2] = $val : splice @{$Conf {$1}}, $2, 1;
  } elsif ($var =~ /^(.*)\{(.*)\}$/) {
    defined $val ? $Conf {$1} {$2} = $val : delete $Conf {$1} {$2};
  } else {
    defined $val ? $Conf {$var} = $val : delete $Conf {$var};
  }
}

open CONF, ">$opts{f}.new"
  or die "Can't create new configuration file $opts{f}.new: $!\n";
foreach (sort keys %Conf) {
  my $val = Data::Dumper::Dumper ($Conf {$_});
  chomp ($val);
  print CONF "\$Conf {$_} = $val;\n";
}
close CONF;

rename $opts {f}, "$opts{f}.old";
rename "$opts{f}.new", $opts {f};