package LogfileMonitor; 

use strict;
use warnings;
use IO::File;
use File::ReadBackwards;
use DateTime;
use DateTime::Format::DateParse;
use LWP::UserAgent;

#Don't forget trailing slash.
my $filePath = '/var/log/';
my @fileNames = ('gateways.log', 'system.log');
my $slackHandle = my handle
my $token = my token


# main Function
sub LFM(){
	my $run = 1;
	my $test = 0;

	while($run && $test < 2){
		for(my $i = 0; $i <= @fileNames; $i++){
			sendMessage($slackHandle, scanFile($filePath,$fileNames[$i]));
			sleep(300);
		}
		$test++;
	}
}

# get relevant Lines from Logfile
sub scanFile(){
	my $currentTime = DateTime->now(time_zone => "local");
	my $handle = File::ReadBackwards->new($_[0] . $_[1]);
	#print $handle;
	print "\n";
	print $_[0].$_[1];
	print "\n\n\n";
	
	for(my $i = 0; $i <= 15; $i++) {
		my $line = $handle->readline;
		if(defined $line) {
			my $messageTime = substr($line, 0, 15);
			my $messageAgent = substr($line, 16, index($line, ':'));
			my $message = substr($line, index($line, ':', 16));

			$messageTime = DateTime::Format::DateParse->parse_datetime($messageTime);

			my $diff = $currentTime->substract($messageTime);

			if ($diff->minutes() <= 5){
				return $line;
			} else {
				return undef;
			}
		}
	}
}

# push Message to Slack
sub sendMessage(){
	my $Messages = $_[1];
	#my $slackHandle = @_[0];
	#my $userAgent = LWP::UserAgent->new();
    #my $data = qq{{ "text" : "@_[1]"}};

	#my $httpRequest = HTTP::Request->new(POST=>$slackHandle);
	#$httpRequest->header('content-type' => 'application/json');
	#$httpRequest->content($data);

 	#my $response = $userAgent->request($httpRequest);
	#if ($response->is_success){
    # 	print $response->decoded_content;
	#}
	#else
    #{
	#    print $response->code;
	#    print $response->message;
    #}
    print $Messages;
}

#Call main Function
LFM();