# This file is part of the Mageia project                                                                                                                   
#
# Copyright (C) 2011 Damien Lallement <dams@mageia.org>                                                                                                   
#           (C) 2011 Romain d'Alverny <rda@mageia.org>                                                                                                    
#                                                                                                                                                         
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
# 
# This library 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
# Library General Public License for more details.
# 
# You should have received a copy of the GNU Library General Public License
# along with this library; see the file COPYING.LIB.  If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
# Boston, MA 02110-1301, USA.
#

=head1 NAME

    MDK::Isocheck - miscellaneous functions

=head1 SYNOPSIS

    use Isocheck;

=head1 EXPORTS

=over 

=item parse_image_file_name(STRING)

return a populated hash if param is a valid image file name
(see https://wiki.mageia.org/en/Product_naming ).

return empty hash if invalid.

=back

=cut

package MDK::ISOcheck;

use strict;
use warnings;

our $VERSION = '0.2.0';

use base 'Exporter';

our @EXPORT = qw(parse_image_file_name is_hybrid hybrid1 hybrid2 hybrid3);

sub parse_image_file_name {
    my ($name) = @_;

    return unless $name =~ m/^
        (
            (\w+)                                # name
            -
            (\d+)                                # version
            (?:-((?:nightly|alpha|beta|RC)\d*))? # release
            (?:-(.+))?                           # variant
            -
            (i586|x86_64|dual)                   # arch
            (?:-(CD|DVD|BR))?                    # medium
            (?:-(build_\w+))?                    # build
        )
        \.
        (\w+)                                    # extension
        $/x;

    my %info = (
        full    => $1,
        name    => $2,
        version => $3,
        defined $4 ? (release => $4) : (),
        defined $5 ? (variant => $5) : (),
        arch    => $6,
        defined $7 ? (medium  => $7) : (),
        defined $8 ? (build   => $8) : (),
        ext     => $9
    );

    return %info;
}

# Verification if the ISO is hybrid
sub is_hybrid {
    my ($img, $full) = @_;

    open(my $iso, $img);
    my $hybrid = hybrid1($iso);
    $hybrid   &= hybrid2($iso);
    $hybrid   &= hybrid3($iso);
    if ($full) {
        # system "dd if=$img of=/dev/my-pendrive bs=8";
    }
    close($iso);

    return $hybrid;
}


# Check the first 512 bytes of the iso
sub hybrid1 {
    my ($iso) = @_;
    my $buffer;
    my $hybrid;

    foreach (0 .. 512) {
        read($iso, $buffer, 1);
        if ($buffer ne '\x00') {
            $hybrid = 1;
        }
    }

    return $hybrid;
}

#Check the 0x1fe & 0x1ff bytes of the iso
sub hybrid2 {
    my ($iso) = @_;
    my $hybrid;
    my $buffer;
    my $byte = "\x55";

    seek($iso, 0x1fe, 0);
    read($iso, $buffer, 1);
    if ($buffer eq $byte) {
        read($iso, $buffer, 1);
        $byte = "\xaa";
        if ($buffer eq $byte) {
            $hybrid = 1;
        }
    }

    return $hybrid;
}

# check from the 0x200 to the 0x8000 bytes
sub hybrid3 {
    my ($iso)  = @_;
    my $hybrid = 1;
    my $buffer;

    seek($iso, 0x200, 0);
    foreach (0x200 .. 0x8000) {
        read($iso, $buffer, 1);
        if ($buffer eq '\x00') {
            $hybrid = 0;
        }
    }

    return $hybrid;
}

1;