################################################
# This script is used to get some interesting  #
# information from the latest kernel ChangeLog #
# -------------------------------------------- #
# Usage: kernel-stats.pl changelog-version.txt #
################################################

#!/usr/bin/perl

@stat = stat($ARGV[0]);
$size = $stat[7];

while (<>) {
	if ($ret = isValidEmail($_)) {
		#print "$ret\n";
		$hash{$ret}++;
	}
	$line_count++;
	$ret = "";
}

@emails = keys(%hash);
$all_emails = join("\n",@emails);
$num_emails = scalar(@emails);

@sort = sort{$hash{$b} <=> $hash{$a}} keys %hash;
for ($i = 0;$i<5;$i++) {
	$name = $sort[$i];
	$count = $hash{$name};
	$top_five .= "$name submitted $count patches\n";
}

print "Size in bytes: $size\n";
print "Number of lines: $line_count\n";
print "Unique contributors: $num_emails\n";
print "\nTop contributors:\n$top_five";

sub isValidEmail() {
	my $line = shift();

	if ($line =~ /([\w-]+(?:\.[\w-]+)*@(?:[\w-]+\.)+[a-zA-Z]{2,7})/) {
		return $1;
	}
}