#!/usr/bin/perl

(our $VERSION) = q(Id: genhdlist2 20460 2006-11-23 13:19:11Z pixel ) =~ /(\d+\.\d+)/;

use URPM;
use MDV::Packdrakeng;
use Getopt::Long;

main();

sub usage () {
    require Pod::Usage;
    Pod::Usage::pod2usage({ '-verbose' => 1 });
}

sub main() {
    my %options;

    GetOptions(
	'clean' => \$options{no_incremental},
	'no-bad-rpm' => \$options{no_bad_rpm},
	'no-md5sum' => \$options{no_md5sum},
	'nolock' => \$options{nolock},
	'file-deps=s' => \$options{file_deps},
	'h|help' => sub { usage(); exit 0 },
	'q|quiet' => sub { $options{verbose} = -1 },
	'v|verbose' => sub { $options{verbose}++ },
	'version' => sub { warn "$0 version $VERSION\n"; exit 0 },
    );

    @ARGV <= 1 or usage();
    my $rpms_dir = $ARGV[0] || '.';

    do_it($rpms_dir, %options);
}

# global vars
my ($no_bad_rpm, $verbose);
my $tmp_header;

sub do_it {
    my ($rpms_dir, %options) = @_;

    $verbose  = $options{verbose};
    $no_bad_rpm = $options{no_bad_rpm};

    my $media_info_dir = "$rpms_dir/media_info";
    -e $media_info_dir || mkdir $media_info_dir or die "Can't mkdir $media_info_dir: $!n";
    -d $media_info_dir && -w _ && -x _ or die "$media_info_dir isn't a writable directory, bailing out\n";

    my $hdlist = "$media_info_dir/hdlist.cz";
    my $synthesis = "$media_info_dir/synthesis.hdlist.cz";
    my $lock_file = "$media_info_dir/UPDATING";
    $tmp_header = "$media_info_dir/.tmp-header";

    my $lock = !$options{nolock} && lock_file($lock_file);

    $SIG{INT} = sub { 
	unlink "$hdlist.tmp", "$synthesis.tmp", $tmp_header;
	unlink $lock_file if $lock;
	exit 1;
    };
    END { unlink $lock_file if $lock }

    my @rpms = grep { /\.rpm$/ } all($rpms_dir);
    my %rpms_todo = map { /(.*)\.rpm/ => 1 } @rpms;

    my $urpm = new URPM;

    read_file_deps($urpm, $options{file_deps}) if $options{file_deps};

    build_hdlist($urpm, \%rpms_todo, $hdlist, $rpms_dir, $options{no_incremental});
    build_synthesis($urpm, "$synthesis.tmp");

    if (1) {
	print "replacing $hdlist with $hdlist.tmp\n" if $verbose >= 0;
	rename "$hdlist.tmp", $hdlist or die "rename $hdlist failed: $?\n";
	print "replacing $synthesis with $synthesis.tmp\n" if $verbose >= 0;
	rename "$synthesis.tmp", $synthesis or die "ERROR: this should not happen: rename $synthesis failed\n";
	generate_md5sum($media_info_dir, $hdlist, $synthesis) if !$options{no_md5sum};
    }
}

sub lock_file {
    my ($file) = @_;
    #- avoid putting a require on Fcntl ':flock' (which is perl and not perl-base).
    my ($LOCK_EX, $LOCK_NB) = (2, 4);

    print "locking $file\n" if $verbose > 0;
    open(my $lock, '>', $file) or die "lock_file $file failed\n";
    flock $lock, $LOCK_EX|$LOCK_NB or die "another genhdlist2 already running\n";
    $lock;
}

sub read_file_deps {
    my ($urpm, $file_deps) = @_;

    -r $file_deps or die "can't read $file_deps: $?\n";

    foreach (cat_($file_deps)) {
	chomp;
	$urpm->{provides}{$_} = undef;
    }
}

sub build_hdlist {
    my ($urpm, $rpms_todo, $hdlist, $rpms_dir, $b_no_incremental) = @_;

    my $out = MDV::Packdrakeng->new(
	archive => "$hdlist.tmp",
	compress => "gzip",
	uncompress => "gzip -d",
	comp_level => 9,
    ) or die "Can't create archive";

    if (-e $hdlist && !$b_no_incremental) {
	print "filtering $hdlist into $hdlist.tmp\n" if $verbose >= 0;
	filter_existing_hdlist($urpm, $rpms_todo, $hdlist, $out);
    }

    add_new_rpms_to_hdlist($urpm, $rpms_todo, $out, $rpms_dir);
}

sub filter_existing_hdlist {
    my ($urpm, $rpms_todo, $in_hdlist, $out) = @_;

    $urpm->parse_hdlist($in_hdlist, packing => 1, callback => sub {
	my (undef, $pkg) = @_;
	my $fullname = $pkg->fullname;
	if (delete $rpms_todo->{$fullname}) {
	    print "keeping $fullname\n" if $verbose > 1;
	    add_pkg_header($out, $pkg);
	    1; # do keep in memory
	} else {
	    print "removing $fullname\n" if $verbose > 0;
	    0; # don't keep in memory
	}
    });
}

sub add_new_rpms_to_hdlist {
    my ($urpm, $rpms_todo, $out, $rpms_dir) = @_;

    my @rpms = keys %$rpms_todo or return;
    if ($verbose >= 0) {
	if (@rpms > 100 || $verbose == 0) {
	    print "adding ", int(@rpms), " new rpms not available in existing hdlist\n";
	} else {
	    print "adding ", join(' ', @rpms), "\n";
	}
    }

    foreach (@rpms) {
	print "adding $_\n" if $verbose > 1;

	my $rpm = "$rpms_dir/$_.rpm";
	my ($id, undef) = $urpm->parse_rpm($rpm);
	if (!defined $id) {
	    if ($no_bad_rpm) {
		print STDERR "bad rpm $rpm\n";
		next;
	    } else {
		die "bad rpm $rpm\n";
	    }
	}
	my $pkg = $urpm->{depslist}[$id];
	add_pkg_header($out, $pkg);

	$pkg->pack_header; # for synthesis
    }
}

sub add_pkg_header {
    my ($out, $pkg) = @_;
    {
	open(my $fh, ">", $tmp_header);
	$pkg->build_header(fileno $fh);
    }
    {
	open(my $fh, "<", $tmp_header);
	$out->add_virtual('f', scalar($pkg->fullname), $fh);
    }
    unlink $tmp_header;
}

sub build_synthesis {
    my ($urpm, $synthesis) = @_;
    $urpm->build_synthesis(
	start     => 0,
	end       => $#{$urpm->{depslist}},
	synthesis => $synthesis,
    ) or die "build_synthesis failed (disk full?)\n";
}

sub generate_md5sum {
    my ($media_info_dir, $hdlist, $synthesis) = @_;
    print "updating $media_info_dir/MD5SUM\n" if $verbose >= 0;
    my $m = `/usr/bin/md5sum '$hdlist' '$synthesis'`;
    open my $f, '>', "$media_info_dir/MD5SUM" or die "Can't write MD5SUM: $!\n";
    print $f $m;
}


sub cat_ { my @l = map { my $F; open($F, '<', $_) ? <$F> : () } @_; wantarray() ? @l : join '', @l }

sub all {
    my $d = shift;

    local *F;
    opendir F, $d or return;
    my @l = grep { $_ ne '.' && $_ ne '..' } readdir F;
    closedir F;

    @l;
}

__END__

=head1 NAME

genhdlist2 - generates an hdlist and a synthesis file

=head1 SYNOPSIS

    genhdlist2 [options] [dir]

=head1 OPTIONS

=over 4

=item B<--clean>

Do not use existing hdlist.cz, build hdlist from scratch.

=item B<--no-md5sum>

Do not generate MD5SUM file.

=item B<--no-bad-rpm>

Do not abort on bad rpms.

=item B<--nolock>

Don't lock the media (can be useful when locks fail, eg NFS). Since the lock
is used to verify no other genhdlist2 process is running on the same media, it
is a dangerous option.

=item B<-v>

Be verbose. Use one more B<-v> to get even more verbose.

=item B<--quiet>

Quiet mode.

=back

=head1 DESCRIPTION

F<genhdlist2> is used to generate an hdlist and an associated synthesis file
from a set of RPM packages found in the directory passed on the command-line.
It will put the hdlist and synthesis files in media_info/ sub-directory.

Without B<--clean>, F<genhdlist2> is incremental, ie it will modify existing
media_info/hdlist.cz: it will first remove package headers for packages that
are no more in the directory. It will then add new packages. This makes an
important assumption: name-version-release-arch is enough to uniquely
indentify a package. So if foo-1-1 is in hdlist, genhdlist2 will keep it and
not bother verifying if it really is the same package.

=head1 SEE ALSO

gendistrib(1), parsehdlist(1)

=head1 COPYRIGHT

Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005 MandrakeSoft SA

Copyright (C) 2005, 2006 Mandriva SA

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, 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

=cut