use DateTime;

sub Avg_Time_Taken_Per_Transaction 
{
	avg_time_taken_in_QnA(@log_paths);
	

}
sub avg_time_taken_in_QnA
{
	print "in avg_time_taken_in_QnA\n";
	die if not @_;
	print "@_\n";
	my @log_files = @_;
	open(AVG_OUT,">avg_time") or die "cannot create file avg_time for writing";
	my %mon2num = qw(
		 Jan 1  Feb 2  Mar 3  Apr 4  May 5  Jun 6
		 Jul 7  Aug 8  Sep 9  Oct 10 Nov 11 Dec 12
		);

    my ( $start_dt, $end_dt );

	for my $log_file (@log_files) 
	{ 
		open my $log, '<', $log_file or die "Can't open '$log_file' for reading."; 
		printf AVG_OUT "Processing file $log_file...\n"; 
		while( <$log> ) 
		{ 
			s{\s+\z}{};
			#m/^\s*\w+\s+(\w+)\s+(\d+)\s+(\d\d:\d\d:\d\d\.\d\d\d)\s+(\d+)\s+..*pid\s+(\d+)\s+tid\s+(\d+):..*RiskServer : Read.*/i)
		    if (/(?:Entering|Exiting) QnAModule::authenticate/)
			{
				$end_dt = '';
				my @dtA = split;
				my @time = split /[:.]/, $dtA[3];
				
					( /Exiting/ ? $end_dt : $start_dt ) = DateTime->new(
					year       => $dtA[4],
					month      => $mon2num{ $dtA[1] },
					day        => $dtA[2],
					hour       => $time[0],
					minute     => $time[1],
					second     => $time[2],
					nanosecond => $time[3],
					);
				

			if ($end_dt && $start_dt)
			{
				printf AVG_OUT "start: ", $start_dt, "\n";
			    printf AVG_OUT "end: ",   $end_dt,   "\n";
				my $e = $end_dt->subtract_datetime($start_dt);
				printf	AVG_OUT "elapsed time for QnA Module: %s year(s), %s month(s), %s week(s), %s day(s), %s hour(s), %s min, %s sec, %s ms\n",
                $e->years, $e->months, $e->weeks, $e->days, $e->hours,
                $e->minutes, $e->seconds, $e->nanoseconds;

		     }
	    }
     }
	 close $log or warn;
   }
   close (AVG_OUT);
}