#!/usr/bin/perl
#
# Script to produce a template adding the packages corresponding to the
# RPMs present in a RPM repository or in file listing all RPMs as URLs
#
# 2 common uses of this script are :
#  - Producing a template adding all trusted CAs.
#  - Producing a template adding all required RPMs for a gLite service from
#    the standard gLite description.
#
# Written by Michel Jouvin - LAL / CNRS - <jouvin@lal.in2p3.fr>

use strict;
use File::Basename;
use Getopt::Long;


# Obsolete RPMs are sometimes still distributed... (e.g. obsolete CAs) 
# RPMS listed here will be included in the template commented out.
# Value has no importance, can be set to the version where it has been obsoleted
my %obsolete_rpms = ( "lcg_FNAL_KCA" => "1.7-1",
                   );


my $rpms_dir = ".";
my $rpm_list = undef;
my $template_name = undef;
my $pan_ns = undef;
my $verbose = 0;


# Process the script arguments

my %options = ();
&GetOptions(\%options, "help", 
                       "namespace=s", 
                       "rpmlist=s",
                       "template=s",
                       "url=s",
                       "verbose") or usage();

if ( defined($options{help}) ) {
  usage();
}

if ( defined($options{verbose}) ) {
  $verbose = 1;
}
 
if ( defined($options{namespace}) ) {
  $pan_ns = $options{namespace};
}
 
if ( defined($options{template}) ) {
  $template_name = $options{template};
}
 
if ( defined($options{rpmlist}) ) {
  $rpm_list = $options{rpmlist};
}

if ( defined($options{url}) ) {
  print STDERR ("Not yet implemented");
  exit 3;
}
 
my @rpms;
if ( defined($rpm_list) ) {
  open (RPMSLIST, $rpm_list) || die 'Unable to open RPMs list '.$rpm_list;
  @rpms = grep (/\.rpm/, <RPMSLIST>);
  close RPMSLIST;
  for (my $i=0; $i<@rpms; $i++) {
    $rpms[$i] =~ s%^.*/%%;
  }
  
} else {
  if ( @ARGV == 0 ) {
    print STDERR "Missing RPMs directory or an RPM list\n";
    usage();
  }
  $rpms_dir = $ARGV[0];
  if ( ! -d $rpms_dir ) {
    print STDERR "RPM directory ($rpms_dir) not found\n";
    exit 2;
  }

  opendir (RPMSDIR, $rpms_dir) || die 'Unable to get current directory listing';
  @rpms = grep /\.rpm$/, readdir(RPMSDIR);
  close RPMSDIR;
}

my $first = 1;

my $pan_name;
if ( defined($template_name) ) {
  $pan_name = basename($template_name,'.tpl');  
} else {
  $pan_name = 'config';
}

if ( defined($pan_ns) && ($pan_ns !~ /\/$/) ) {
  $pan_ns .= '/';
}

my $template_handle;
if ( defined($template_name) ) {
  open(TEMPLATE, ">$template_name") || die "Error creating template $template_name";
}

for my $rpm (@rpms) {
  if ( $first ) {
    $first = 0;
    if ( defined($template_name) ) {
      print TEMPLATE "unique template ".$pan_ns.$pan_name.";\n\n";
    } else {
      print "unique template ".$pan_ns.$pan_name.";\n\n";      
    }
  }

  if ( $verbose ) {
    print STDERR "Processing $rpm\n";
  }
  my ($name, $version, $release, $arch) = ($rpm =~ m/\s*(.+)-((?:[^-]+)-(?:[^-]+))\.([^\.]+)\.rpm\s*$/);
  unless ( $name ) {
    print STDERR "Skipping $rpm (doesn't match a RPM name)\n";
  }
  my $prefix = '';
  if ( exists($obsolete_rpms{$name}) ) {
    $prefix = '#';
  }
  if ( defined($template_name) ) {
    print TEMPLATE $prefix."'/software/packages' = pkg_repl('$1', '$2', '$3');\n";
  } else {
    print $prefix."'/software/packages' = pkg_repl('$1', '$2', '$3');\n";    
  }

}


# Print the usage instructions for this script.
sub usage {
  print << 'EOF'
Usage:  createPackagesTemplate [--namespace pan_namespace] \
                               [--template template_name] \
                               [--rpmlist rpm_list] \
                               [--url Source_URL] \
                               [--verbose] \
                               [RPM_directory]

    --namespace (-n) pan_namespace : PAN namespace to use
    
    --rpmlist (-r) file : a file with a list of RPM, one per line.
                     Each RPM can be a URL or a file specification.
         
    --template (-t) file : name of the template to create. If not present, defaults
                      to stdout and PAN template name defaults to 'config'.

    --url (-u) Source_URL : URL to download RPMs from before producing the template.
                       All missing RPMs will be downloaded to RPM_Directory. 
    
    --verbose (-v) : verbose output
    
    'RPM_directory' is a directory path containing the RPMs to be included.
    This parameter is ignored if '--rpmlist' is specified, required otherwise.
    All RPMs in this directory are included in the template.
     
EOF
;

  exit 1;
}