#!/usr/bin/perl -w

=head1 NAME

Alien::Package::Tgz - an object that represents a tgz package

=cut

package Alien::Package::Tgz;
use strict;
use base qw(Alien::Package);
use Cwd qw(abs_path);

my $tarext=qr/\.(?:tgz|tar(?:\.(?:gz|Z|z|bz|bz2))?|taz)$/;

=head1 DESCRIPTION

This is an object class that represents a tgz package, as used in Slackware. 
It also allows conversion of raw tar files.
It is derived from Alien::Package.

=head1 CLASS DATA

=over 4

=item scripttrans

Translation table between canoical script names and the names used in
tgz's.

=cut

use constant scripttrans => {
		postinst => 'doinst.sh',
		postrm => 'delete.sh',
		prerm => 'predelete.sh',
		preinst => 'predoinst.sh',
	};

=back

=head1 METHODS

=over 4

=item checkfile

Detect tgz files by their extention.

=cut

sub checkfile {
        my $this=shift;
        my $file=shift;

        return $file =~ m/$tarext$/;
}

=item install

Install a tgz with installpkg. Pass in the filename of the tgz to install.

installpkg (a slackware program) is used because I'm not sanguine about
just untarring a tgz file. It might trash a system.

=cut

sub install {
	my $this=shift;
	my $tgz=shift;

	if (-x "/sbin/installpkg") {
		my $v=$Alien::Package::verbose;
		$Alien::Package::verbose=2;
		$this->do("/sbin/installpkg", "$tgz")
			or die "Unable to install";
		$Alien::Package::verbose=$v;
	}
	else {
		die "Sorry, I cannot install the generated .tgz file because /sbin/installpkg is not present. You can use tar to install it yourself.\n"
	}
}

=item scan

Scan a tgz file for fields. Has to scan the filename for most of the
information, since there is little useful metadata in the file itself.

=cut

sub scan {
	my $this=shift;
	$this->SUPER::scan(@_);
	my $file=$this->filename;

	# Get basename of the filename.
	my ($basename)=('/'.$file)=~m#^/?.*/(.*?)$#;

	# Strip out any tar extentions.
	$basename=~s/$tarext//;

	if ($basename=~m/([\w-]+)-([0-9\.?]+).*/) {
		$this->name($1);
		$this->version($2);
	}
	else {
		$this->name($basename);
		$this->version(1);
	}

	$this->arch('all');

	$this->summary("Converted tgz package");
	$this->description($this->summary);
	$this->copyright('unknown');
	$this->release(1);
	$this->distribution("Slackware/tarball");
	$this->group("unknown");
	$this->origformat('tgz');
	$this->changelogtext('');
	$this->binary_info($this->runpipe(0, "ls -l '$file'"));

	# Now figure out the conffiles. Assume anything in etc/ is a
	# conffile.
	my @conffiles;
	open (FILELIST,"tar vtf $file | grep etc/ |") ||
		die "getting filelist: $!";
	while (<FILELIST>) {
		# Make sure it's a normal file. This is looking at the
		# permissions, and making sure the first character is '-'.
		# Ie: -rw-r--r--
		if (m:^-:) {
			# Strip it down to the filename.
			m/^(.*) (.*)$/;
			push @conffiles, "/$2";
		}
	}
	$this->conffiles(\@conffiles);

	# Now get the whole filelist. We have to add leading /'s to the
	# filenames. We have to ignore all files under /install/
	my @filelist;
	open (FILELIST, "tar tf $file |") ||
		die "getting filelist: $!";
	while (<FILELIST>) {
		chomp;
		unless (m:^install/:) {
			push @filelist, "/$_";
		}
	}
	$this->filelist(\@filelist);

	# Now get the scripts.
	foreach my $script (keys %{scripttrans()}) {
		$this->$script(scalar $this->runpipe(1, "tar Oxf '$file' install/${scripttrans()}{$script} 2>/dev/null"));
	}

	return 1;
}

=item unpack

Unpack tgz.

=cut

sub unpack {
	my $this=shift;
	$this->SUPER::unpack(@_);
	my $file=abs_path($this->filename);

	$this->do("cd ".$this->unpacked_tree."; tar xpf $file")
		or die "Unpacking of '$file' failed: $!";
	# Delete the install directory that has slackware info in it.
	$this->do("cd ".$this->unpacked_tree."; rm -rf ./install");

	return 1;
}

=item prep

Adds a populated install directory to the build tree.

=cut

sub prep {
	my $this=shift;
	my $dir=$this->unpacked_tree || die "The package must be unpacked first!";

	my $install_made=0;
	if ($this->usescripts) {
		foreach my $script (keys %{scripttrans()}) {
			my $data=$this->$script();
			my $out=$this->unpacked_tree."/install/".${scripttrans()}{$script};
			next if ! defined $data || $data =~ m/^\s*$/;
			if (!$install_made) {
				mkdir($this->unpacked_tree."/install", 0755) 
					|| die "unable to mkdir ".$this->unpacked_tree."/install: $!";
				$install_made=1;
			}
			open (OUT, ">$out") || die "$out: $!";
			print OUT $data;
			close OUT;
			$this->do("chmod", 755, $out);
		}
	}
}

=item build

Build a tgz.

=cut

sub build {
	my $this=shift;
	my $tgz=$this->name."-".$this->version.".tgz";

	$this->do("cd ".$this->unpacked_tree."; tar czf ../$tgz .")
		or die "Package build failed";

	return $tgz;
}

=back

=head1 AUTHOR

Joey Hess <joey@kitenet.net>

=cut

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