#!/usr/bin/perl
use strict;
use warnings;

use RRD::Simple ();
use Data::Dumper;

$| = 1;    # Flush the output

my ($unixtime,$rrd);

my $file = "perl.txt";
my $path    = '/home/tiny_os/Desktop/Test_Perl/';
my $period  = '3years';
my $rrdfile = 'myfile';

while (sleep 1) {

    open(FH, ">>", $file) || die "Unable to open $file: $!\n";

    my $range   = 50;
    my $minimum = 100;

    my $random_number_in  = int(rand($range)) + $minimum;
    my $random_number_out = int(rand($range)) + $minimum;
    my $random_number_sec = int(rand($range)) + $minimum;

    $rrd = RRD::Simple->new(
        file => "".$rrdfile."",
        rrdtool => "/usr/bin/rrdtool", #optional /usr/bin/rrdtool
	tmpdir => "/tmp", #optional
        cf => [ qw( AVERAGE MIN MAX LAST ) ], #optional
        default_dstype => "COUNTER", #optional
        on_missing_ds => "add", #optional
        );

=comment
	# Create an interface object
	$rrd = RRD::Simple->new(
	    file => $rrdfile,
	    cf   => [qw( AVERAGE MIN MAX LAST )],
	    #default_dstype => "DERIVE",
	);
=cut

	# Create a new RRD file with 3 data sources called
	# bytesIn, bytesOut and faultsPerSec.
    unless (-e $rrdfile) {
	$rrd->create(
	    $period,
	    bytesIn      => "COUNTER",
	    bytesOut     => "COUNTER",
	    faultsPerSec => "COUNTER"
	    );
	RRDs::tune("".$rrdfile.".rrd", "-i", "Source_Name:0"), #optional -i or --minimum
	RRDs::tune("".$rrdfile.".rrd", "-a", "Source_Name:4294967295") #optional -a or --maximum
    }

=comment
	32-bit = 2^32-1 = 4294967295 (counter ticks)
	64-bit = 2^64-1 = 18446744073709551615 (counter ticks)
	64-bit counter (caution!!!) different oid's

	// ifInOctets (OID: 1.3.6.1.2.1.2.2.1.10)
	// ifOutOctets (OID: 1.3.6.1.2.1.2.2.1.16)
	// sysUpTime (OID: 1.3.6.1.2.1.1.3)
=cut

    # Put some arbitary data values in the RRD file for the same
    # 3 data sources called bytesIn, bytesOut and faultsPerSec.
    $rrd->update(
	bytesIn      => $random_number_in,
	bytesOut     => $random_number_out,
	faultsPerSec => $random_number_sec
	);

    print FH "This is the bytes_in: $random_number_in\n";
    print FH "This is the bytes_out: $random_number_out\n";
    print FH "This is the bytes_sec: $random_number_sec\n";

    # Generate graphs:
    # /home/tiny_os/Desktop/Test_Perl/myfile-hourly.png, /home/tiny_os/Desktop/Test_Perl/myfile-daily.png
    # /home/tiny_os/Desktop/Test_Perl/myfile-weekly.png, /home/tiny_os/Desktop/Test_Perl/myfile-monthly.png

    my %rtn = $rrd->graph(
	$rrdfile,
	destination => $path,
	basename    => "".$rrdfile."_graph",
	timestamp   => "both",                       # graph, rrd, both or none
	periods     => [qw(hour day week month)],    # omit to generate all graphs
	sources          => [qw(bytesIn bytesOut faultsPerSec)],
	source_colors    => [qw(9932CC 0000CD FFFF00)],	
	source_labels    => [("Bytes In", "Bytes Out", "Faults Per Second")],
	source_drawtypes => [qw(LINE LINE LINE)], # AREA , LINE, LINE1
	line_thickness   => 2,
	extended_legend  => 1,
	title            => "Network Interface eth0",
	vertical_label   => "Bytes/Faults",
	width            => 800,
	height           => 500,
	interlaced       => "", # If images are interlaced they become visible to browsers more quickly
	);

    #printf("Created %s\n", join(", ", map { $rtn{$_}->[0] } keys %rtn));

    # Return information about an RRD file
    my $info = $rrd->info($rrdfile); # This method will return a complex data structure containing details about the RRD file, including RRA and data source information.
    #print Data::Dumper::Dumper($info);

    my @sources = $rrd->sources($rrdfile);
    my $seconds = $rrd->retention_period($rrdfile); # This method will return the maximum period of time (in seconds) that the RRD file will store data for.

    # Get unixtime of when RRD file was last updated
    $unixtime = $rrd->last($rrdfile);
    print FH "".$rrdfile.".rrd was last updated at " . scalar(localtime($unixtime)) . "\n";

    # Get list of data source names from an RRD file
    my @dsnames = $rrd->sources;
    print "Available data sources: " . join(", ", @dsnames) . "\n";
    my $heartbeat_In  = $rrd->heartbeat($rrdfile, "bytesIn"); # Define the name to use the heartbeat
    my $heartbeat_Out = $rrd->heartbeat($rrdfile, "bytesOut");
    my $heartbeat_sec = $rrd->heartbeat($rrdfile, "faultsPerSec");  # This method will return the current heartbeat of a data source.

    printf "This is the heartbeat_in: %s\n", $heartbeat_In;
    my @rtn_In  = $rrd->heartbeat($rrdfile, "bytesIn",      10); # Based on the predifined name set the step
    my @rtn_Out = $rrd->heartbeat($rrdfile, "bytesOut",     10);
    my @rtn_sec = $rrd->heartbeat($rrdfile, "faultsPerSec", 10);    # This method will set a new heartbeat of a data source.

    close(FH);
}