#!/usr/bin/perl -w

use Getopt::Std;

my $confQsub    = "/usr/bin/qsub"; # qsub command
my $confShell   = "/bin/sh";       # the submit script is written for this shell
my $confMaxAge  = 7*24*60*60;      # maximum life time for files in $HOME/.pbsrun: 7 days
my $confHistory = "history.txt";

my $workdir = gotoWorkDir();
cleanup();

getopts('nvN:m:e:q:o:h');

printHelpAndExit() if ($opt_h) || (@ARGV < 1);

if ($opt_m)
  {
    die "pbsrun: -m argument [$opt_m] does not look like an email address\n" unless $opt_m =~ /.*@.*/;
    $opt_m = "-m abe -M $opt_m";
  }
else
  {
    $opt_m = "-m n";
  }

$opt_N = '\"'.$ARGV[0].'\"' unless $opt_N;

$opt_q = "-q " . $opt_q        if $opt_q;

0 if $opt_n;
0 if $opt_h;
0 if $opt_v;
$opt_o = "" if !$opt_o;
$opt_q = "" if !$opt_q;

my $cmd = join(" ",@ARGV);


my $jobName = NewJob();

WriteHistory(time(),$jobName,"Command: ",$cmd);

open(JOBFILE,">$jobName.script") || die "pbsrun: Could not open $jobName: $!\n";

print JOBFILE "#!$confShell\n";
print JOBFILE "# This file was generated automatically.\n"; 
print JOBFILE "# on ".(scalar localtime)."\n";
print JOBFILE "#\n";
print JOBFILE "# restore the user environment\n";
foreach my $key (sort keys %ENV)
  {
    next if ($key eq "DISPLAY");
    next if ($key eq "HOSTNAME");
    next if ($key eq "HOSTTYPE");
    next if ($key eq "LOGNAME");
    next if ($key eq "MACHTYPE");
    next if ($key eq "MAIL");
    next if ($key eq "OSTYPE");
    next if ($key eq "OLDPWD");
    next if ($key eq "PWD");
    next if ($key eq "SHELL");
    next if ($key eq "SHLVL");
    next if ($key =~ /^SSH/);
    next if ($key eq "TERM");
    next if ($key eq "USER");
    next if ($key eq "WINDOWID");
    next if ($key eq "LS_COLORS");
    next if ($key eq "XAUTHORITY");
    next if ($key eq "_");
    my $val = $ENV{$key};
    print JOBFILE "export $key=\"$val\"\n";
  }

print JOBFILE "#\n";
print JOBFILE "# restore the user working directory\n";
my $pwd = $ENV{"PWD"};
print JOBFILE "cd $pwd\n" ;
WriteHistory(time(),$jobName,"Pwd: ",$pwd);

print JOBFILE "# save the node name\n";
print JOBFILE "hostname >$workdir/$jobName.hostname\n";
print JOBFILE "# run the user command:\n";
print JOBFILE "(".$cmd.")"." >/dev/null 2>/dev/null\n";
print JOBFILE "# save the exit status: \n";
print JOBFILE "echo \$\? >$workdir/$jobName.status\n";
#print JOBFILE "printenv | grep PBS\n";
#print JOBFILE "set\n";
print JOBFILE "exit \$\?\n";
print JOBFILE "# end of file\n";
close JOBFILE;

my $outputfile = "$workdir/$jobName.stderr";

my $qsubcmd = "$confQsub -S $confShell -r n -j eo -e $outputfile -N $opt_N $opt_o $opt_m $opt_q < $jobName.script";
print "pbsrun: $qsubcmd\n" if $opt_v;

WriteHistory(time(),$jobName,"Qsub: ",$qsubcmd);

if ($opt_n)
  {
    WriteHistory(time(),$jobName,"Pbs job: not submitted");

    print "PBS Job id: not submitted\n";
    print "Job output: $outputfile\n";
  }
else
  {
    my $jobid = submitJob($qsubcmd);
    
    die "pbsrun: Failed to submit the pbs job!\n" if !$jobid;
    
    WriteHistory(time(),$jobName,"Pbs job: ",$jobid);
    
    print "PBS Job id: $jobid\n";
    print "Job output: $outputfile\n";
  }

exit 0;

sub NewJob
  {
    my @now = localtime();
    return sprintf("%04d%02d%02d-%02d%02d%02d-%d",
		   1900+$now[5],1+$now[4],$now[3],
		   $now[2],$now[1],$now[0],$$);
  }

sub submitJob
  {
    my $cmd = shift @_;
    open(QSUBPROC, "$cmd 2>&1 |") || die "pbsrun: Cannot spawn $confQsub: $!\n";

    my $jobid;
    
    while (<QSUBPROC>)
      {
	print "qsub: ".$_ if $opt_v;
	$jobid = $_ if /^\d+/;
      }
    close QSUBPROC;

    $jobid =~ s/\n$// if defined $jobid;

    return $jobid;
  }

sub gotoWorkDir
  {
    my $workdir = $ENV{"HOME"}."/.pbsrun";
    if (! -d $workdir)
      {
	print "pbsrun: no $workdir directory. Making one.\n";
	mkdir($workdir,0744) || die "pbsrun: Could not make $workdir: $!\n";
      }
    chdir $workdir || die "pbsrun: Cannot chdir to $workdir: $!\n";
    return $workdir;
  }

sub WriteHistory
  {
    my $now = localtime(shift @_);
    open(TMPOUT,">>$confHistory");
    print TMPOUT $now,": job ",shift @_,": ",join("",@_),"\n";
    close TMPOUT;
  }
    
sub cleanup
  {
    my $now = time();
    my @ls = `/bin/ls -1`;
    foreach $ls (sort @ls)
      {
	chop $ls;
	next if $ls eq $confHistory;

	my @stat = stat $ls;
	my $mtime = $stat[9];

	if ($ls =~ /(.*)\.status/)
	  {
	    my $status = `cat $ls`;
	    chop $status;
	    #print "time $mtime, status [$status]\n";
	    WriteHistory($mtime,$1,"Exit status: ",$status);
	    unlink $ls;
	    next;
	  }

	if ($ls =~ /(.*)\.hostname/)
	  {
	    my $hostname = `cat $ls`;
	    chop $hostname;
	    #print "time $mtime, hostname [$hostname]\n";
	    WriteHistory($mtime,$1,"Started on: ",$hostname);
	    unlink $ls;
	    next;
	  }

	my $age = $now - $mtime;

	#print "file [$ls] age: [$age]\n";

	if ($age > $confMaxAge)
	  {
	    unlink $ls;
	  }
      }
  }

sub printHelpAndExit
{
    print "Usage: pbsrun [-q queue] [-N job_name] command...\n";
    print "  Options: \n";
    print "    [-h] Prints out this message.\n";
    print "    [-N job_name]     name this job.\n";
    print "    [-m user\@host]   emails you when the job begin, ends or aborts.\n";
    print "    [-o qsub_options] passes options to the call to qsub.\n";
    print "    [-q queue]        selects a queue.\n";
    print "    [-n] test mode: do not run any pbs commands.\n";
    print "    [-k] keep, do not delete temp files.\n";
    print "    [-v] be verbose, show progress.\n";
    exit 1;
}

#end file