#!/usr/bin/perl
#
# dpkg-vendor
#
# Copyright © 2009 Raphaël Hertzog <hertzog@debian.org>
# Copyright © 2009,2012 Guillem Jover <guillem@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 <https://www.gnu.org/licenses/>.

use strict;
use warnings;

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

textdomain('dpkg-dev');

sub version {
    printf g_("Debian %s version %s.\n"), $Dpkg::PROGNAME, $Dpkg::PROGVERSION;

    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>...] [<command>]')
    . "\n\n" . g_(
'Commands:
  --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.')
    . "\n\n" . g_(
'Options:
  --vendor <vendor>       assume <vendor> is the current vendor.')
    . "\n", $Dpkg::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 $param;
    } elsif (m/^-(?:\?|-help)$/) {
        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();

my $info = get_vendor_info($vendor);
unless (defined($info)) {
    error(g_("vendor %s doesn't exist in %s"), $vendor || 'default',
          get_vendor_dir());
}

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);
    }

}