#!/usr/bin/perl
#
# dpkg-vendor
#
# Copyright © 2009 Raphaël Hertzog <hertzog@debian.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

use strict;
use warnings;

use Dpkg;
use Dpkg::Gettext;
use Dpkg::ErrorHandling;
use Dpkg::Vendor qw(get_vendor_info get_current_vendor);

textdomain("dpkg-dev");

sub version {
    printf _g("Debian %s version %s.\n"), $progname, $version;

    printf _g("
Copyright (C) 2009 Raphael Hertzog <hertzog\@debian.org>.");

    printf _g("
This is free software; see the GNU General Public License version 2 or
later for copying conditions. There is NO warranty.
");
}

sub usage {
    printf _g(
"Usage: %s [<option> ...] [<action>]

Options:
  --vendor <vendor>       assume <vendor> is the current vendor

Actions:
  --is <vendor>           returns true if current vendor is <vendor>.
  --derives-from <vendor> returns true if current vendor derives from <vendor>.
  --query <field>         print the content of the vendor-specific field.
  --help                  show this help message.
  --version               show the version.
"), $progname;
}

my ($vendor, $param, $action);

while (@ARGV) {
    $_ = shift(@ARGV);
    if (m/^--vendor$/) {
        $vendor = shift(@ARGV);
        usageerr(_g("%s needs a parameter"), $_) unless defined $vendor;
    } elsif (m/^--(is|derives-from|query)$/) {
        usageerr(_g("two commands specified: --%s and --%s"), $1, $action)
            if defined($action);
        $action = $1;
        $param = shift(@ARGV);
        usageerr(_g("%s needs a parameter"), $_) unless defined $param;
    } elsif (m/^-(h|-help)$/) {
        usage();
        exit 0;
    } elsif (m/^--version$/) {
        version();
        exit 0;
    } else {
	usageerr(_g("unknown option \`%s'"), $_);
    }
}

usageerr(_g("need an action option")) unless defined($action);

# Uses $ENV{DEB_VENDOR} if set
$vendor = get_current_vendor() unless defined($vendor);

my $info = get_vendor_info($vendor);
unless (defined($info)) {
    error(_g("vendor %s doesn't exist in /etc/dpkg/origins/"),
          $vendor || "default");
}

if ($action eq 'is') {

    exit(0) if lc($param) eq lc($info->{'Vendor'});
    exit(1);

} elsif ($action eq 'derives-from') {

    exit(0) if lc($param) eq lc($info->{'Vendor'});
    while (defined($info) && exists $info->{'Parent'}) {
        $info = get_vendor_info($info->{'Parent'});
        exit(0) if lc($param) eq lc($info->{'Vendor'});
    }
    exit(1);

} elsif ($action eq 'query') {

    if (exists $info->{$param}) {
        print $info->{$param} . "\n";
        exit(0);
    } else {
        exit(1);
    }

}