sub readconfigfile {
  my ($cfgkey, $file) = @_;
  my $path = catfile($config{configfiles}{directory}, $file);
  if (-e $path) {
    open CFG, "<", $path or return nonfatalerror("Unable to read config $path: $!");
    #print " Opened config file $file\n";
    my $slurp = join "", <CFG>; close CFG;
    $config{cfgkey}{fromfile} = $path;
    readconfigtext($config{$cfgkey}, $slurp);
  }
}

sub readconfigscalar {
  my ($text) = @_;
  return if not $text;
  my %closer = ("[" => "]", "{" => "}", '"' => '"', "'" => "'");
  if ($text =~ m/^\s*([[{"'])/) {
    my ($type) = ($1);
    $text =~ s/^\s*([[{"'])//;
    if ($type eq "[") {
      return readconfiglist($text, $closer{$type});
    } elsif ($type eq "{") {
      my ($value, $remainingtext) = readconfiglist($text, $closer{$type});
      return (+{ @$value }, $remainingtext);
    } else {
      return readconfigstring($text, $closer{$type});
    }
  } else {
    my ($line) = $text =~ m/^(.*?)$/;
    nonfatalerror("Failed to parse config scalar: $line");
  }
}

sub readconfiglist {
  my ($text, $closer) = @_;
  my @list;
  while ($text and not $text =~ m/^\s*[$closer]/) {
    if ($text =~ m/^\s*(?:[,]|[=][>])\s*/) {
      push @list, undef;
    } else {
      my ($value, $rest) = readconfigscalar($text);
      push @list, $value;
      $text = $rest;
    }
    $text =~ s/^\s*(?:[,]|[=][>])\s*//;
  }
  $text =~ s/^\s*[$closer]\s*//;
  return (\@list, $text);
}

sub readconfigstring {
  my ($text, $closer) = @_;
  my $string = "";
  while ($text and not $text =~ m/^[$closer]/) {
    my ($substring) = $text =~ m/^([^"'\\])/;
    $string .= $substring;
    $text =~ s/^([^"'\\])//;
    if ($text =~ m/^[\\]([\\"'])/) {
      my ($escaped) = $1;
      $string .= $escaped;
      $text =~ s/^[\\]([\\"'])//;
    }
  }
  $text =~ s/^[$closer]//;
  return ($string, $text);
}

sub readconfigtext {
  my ($cfghash, $text) = @_;
  $text =~ s/^\s*(?:[#].*|)(?:$)\s*//;
  return if not $text;
  print "  <" . length($text) . ">\n";
  my %closer = ("[" => "]", "{" => "}", '"' => '"', "'" => "'");
  if ($text =~ m/^\s*(\w+)\s*[=][>]?\s*([[{"'])/) {
    my ($key, $type) = ($1, $2);
    $text =~ s/^\s*(\w+)\s*[=][>]?\s*([[{"'])//;
    if ($type eq "[") {
      my ($value, $remainingtext) = readconfiglist($text, $closer{$type});
      if ($value) {
        $$cfghash{$key} = $value;
        readconfigtext($cfghash, $remainingtext);
      }
    } elsif ($type eq "{") {
      my ($value, $remainingtext) = readconfiglist($text, $closer{$type});
      if ($value) {
        $$cfghash{$key} = +{ %{$$cfghash{$key}}, @$value };
        readconfigtext($cfghash, $remainingtext);
      }
    } else {
      my ($value, $remainingtext) = readconfigstring($text, $closer{$type});
      if ($value) {
        $$cfghash{$key} = $value;
        readconfigtext($cfghash, $remainingtext);
      }
    }
  } else {
    my ($line) = $text =~ m/^(.*?)$/;
    nonfatalerror("Failed to parse config text: $line");
  }
}

sub cfgscalartostring {
  my ($scalar, $indentlevel) = @_;
  $indentlevel ||= "";
  if ((ref $scalar) eq "ARRAY") {
    return "[" . (join ", ", map { cfgscalartostring($_, $indentlevel . "  ") } @$scalar) . "]\n$indentlevel";
  } elsif ((ref $scalar) eq "HASH") {
    return "{" . (join ", ", map { my $k = $_; cfgscalartostring($k) . " => " . cfgscalartostring($$scalar{$k}, $indentlevel . "  ")  } keys %$scalar) . "}\n$indentlevel";
  } elsif (not defined $scalar) {
    return "";
  } elsif (not ref $scalar) {
    my $string = "" . $scalar;
    $string =~ s/[\\]/\\\\/;
    $string =~ s/(['"])/\\$1/;
    return '"' . $string . '"';
  }
}

sub writeconfigfile {
  my ($cfgkey, $file) = @_;
  my $path = catfile($config{configfiles}{directory}, $file);
  open CFG, ">", $path or return nonfatalerror("Unable to write config file $path: $!");
  my $cfghash = $config{$cfgkey};
  for my $key (keys %$cfghash) {
    print CFG "$key = " . cfgscalartostring($$cfghash{$key}) . "\n";
  }
  close CFG;
}