#!/usr/bin/perl
# grader / Min-Yen Kan / Version 1.0 / Wed May 12 13:10:26 EDT 1999
#
#	Fixed version from yee fan
#
#	Looks for commands such as (time) (max) (score) (mailto:email@address) 
#	in input files.  Tallies scores based on (+/-number%?), e.g. (-5%) or (+5).
#	maximum scores are specified by square brackets [25 points] or [25].
#
#	Other features
#	- A "BUG" in the input file will cause the file in question to
#	not be processed in the current run, so you can fix it later.
#	- Ignores lines starting with "#"
#	- Calculates score, # of submissions, avg, and standard
#	deviation on STDERR
# 
# 	Changed by Min (Mon Dec 17 20:49:21 SGT 2012)
#	- Added debugging output via command-line opt "-d"
#
require "getopts.pl";

### USER customizable section
$tmpfile .= $0; $tmpfile =~ s/[\.\/]//g; $tmpfile = "/tmp/" . $tmpfile . $$ . time;
$0 =~ /([^\/]+)$/; $progname = $1;
$mailtoCommandLoc = "/usr/bin/mail";				      # you may have to change this
$defaultSubject = "Your grade";
### END user customizable section

### Ctrl-C handler
sub quitHandler {
  print STDERR "\n# $progname fatal - received a 'SIGINT'\n# $progname - exiting cleanly\n";
  `/bin/rm $tmpfile`;
  exit;
}

### HELP Sub-procedure
sub Help {	
  print STDERR "usage: $progname -h\t\t\t\t[invokes help]\n";	
  print STDERR "       $progname -v\t\t\t\t[invokes version]\n";	
  print STDERR "       $progname [-qm] [-s <subject>] filename(s)...\n";	
  print STDERR "Options:\n";
  print STDERR "\t-q\tQuiet Mode (don't echo license)\n";
  print STDERR "\t-m\tProcess mailto commands\n";
  print STDERR "\t-s <subj>\tAssign mail subject (default: $defaultSubject)\n";
  print STDERR "\n";
  print STDERR "Will accept input on STDIN as a single file.\n";
  print STDERR "\n";
}

### VERSION Sub-procedure
sub Version {
  open (IF, $0);
  while (<IF>) {
    if (/^\#/) { 
      if (/^\#\!/) { next; } else { s/^\#//; print STDERR $_; }
    } else { last; }
  }
}

sub License {
  print STDERR "# Copyright 1999,2003 \251 by Min-Yen Kan\n";
}

###
### MAIN program
###

$SIG{'INT'} = 'quitHandler';
&Getopts ('dhmqs:v');

if (!$opt_q) { &License; }	   # call License, if asked for
if ($opt_v) { &Version; exit(0); } # call Version, if asked for
if ($opt_h) { &Help; exit (0); }   # call help, if asked for
my $subject = (defined $opt_s) ? $opt_s : $defaultSubject; 

my $multi = 0;
if (scalar (@ARGV) > 2) { $multi = 1; }
@grades = ();

## standardize input stream (either STDIN on first arg on command line)
if ($filename = shift) {
 NEWFILE:
  if (!(-e $filename)) { die "# $progname crash\t\tFile \"$filename\" doesn't exist"; }
  open (IF, $filename) || die "# $progname crash\t\tCan't open \"$filename\"";
  $fh = "IF";
} else {
  $filename = "<STDIN>";
  $fh = "STDIN";
}

$i = 0;
$time = localtime(time());
@mailto = ();
my $max = 0;
my $score = 0;
my $percent = 100;
my $bug = 0;
while (<$fh>) {
  if (/^\#/) { next; }						      # skip comments
  s/
//;
  s/\(time\)/$time/g;						      # get the current, grading time
  
  if (/\(mailto\:(.+)\)/g) {					      # get the email address, if defined
    push (@mailto, $1);
    if (!defined $opt_m) {
      print STDERR "# $progname warning\t\tNo mailing switch (-m) on command line, ignoring mailtos...\n"; 
    }
  }

  if (/BUG/) {							      # check whether can be done
    $bug = 1;
    print STDERR "# $progname warning\t\t\"BUG\" keyword found in text \"$filename\", not going to process\n";
  }

  while (/\(([+-])(\d+)(%?)\)/g) {				      # add or subtract a (percentage) grade
    $sign = $1;
    $val = $2;
    $percentage = $3;
    if ($percentage eq "") {
      if ($sign eq '-') {
	$score -= $val;
	if ($opt_d) { print STDERR "[- $val: $score]"; }
      } else {
	$score += $val;
	if ($opt_d) { print STDERR "[+ $val: $score]"; }
      }
    } else {
      if ($sign eq '-') {
	$percent -= $val;
	if ($opt_d) { print STDERR "[- $val %: $percent %]"; }
      } else {
	$percent += $val;
	if ($opt_d) { print STDERR "[+ $val %: $percent %]"; }
      }
    }
  }
  
  while (/\[(\d+) point(s?)\]/g) {					      # compile maximum score
    $max += $1;
    $score += $1;
    if ($opt_d) { print STDERR "[acc $1: $score / max: $max]"; }
  }
  
  $lines[$i++] = $_;						      # store annotated template file
}

close ($fh);

# recalculate raw score from percentage.
$score = int (($percent/100) * $score);

## 2nd pass
if (defined @mailto && scalar (@mailto) != 0) {
  open (OF, ">$tmpfile");
  $fh = "OF";
} else {
  $fh = "stdout";
}

if ($bug == 1) { print $fh "BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG\n"; }
if (defined @mailto && scalar (@mailto) != 0) {
  unshift (@lines,
	   "If you are not the intended recipient of this automated grade e-mail,\n",
	   "please simply reply to this e-mail, and then delete it. Thank you.\n\n\n");
  unshift (@lines, "Subject: $subject\n\n");
}

push (@grades, $score);
for ($i = 0; $i <= $#lines; $i++) {
  $lines[$i] =~ s/\(score\)/$score/g;
  $lines[$i] =~ s/\(max\)/$max/g;
  print $fh $lines[$i];
  if ($fh eq "OF") { print $lines[$i]; } 
}

if (defined @mailto && scalar (@mailto) != 0 && $opt_m) {
  close ($fh);
  for (my $i = 0; $i <= $#mailto; $i++) {
    system ("$mailtoCommandLoc $mailto[$i] < $tmpfile");
  }
  `rm $tmpfile`;
}
if ($bug == 1) { print $fh "BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG BUG\n"; }

if ($multi == 1) { print STDERR "# $progname info\t\t$filename : $score\n"; }

if ($filename = shift) {
  print "--------------------------------------------------------------------------------\n";
  $i = 0;
  undef @lines;
  goto NEWFILE;
}

if ($multi == 1) {
  my $sum = 0;
  for (my $i = 0; $i <= $#grades; $i++) {
    $sum += $grades[$i];
  }
  my $avg = $sum / scalar (@grades);
  print STDERR "# $progname info\t\tNumber of assignments = " . scalar (@grades) . "\n";
  print STDERR "# $progname info\t\tAverage grade = $avg\n";

  my $diff = 0;
  for (my $i = 0; $i <= $#grades; $i++) {
    $diff += (abs($avg - $grades[$i]) * abs($avg - $grades[$i]));
  }
  my $std = $diff / (scalar (@grades) - 1);
  my $std = sqrt ($std);
  print STDERR "# $progname info\t\tStandard Deviation = $std\n";

}
### 
### END of main program
###