#!/usr/bin/perl -w

use constant TREND_DOWN         => 0;
use constant TREND_DOWN_WEAK    => 1;
use constant TREND_FLAT         => 2;
use constant TREND_UP_WEAK      => 3;
use constant TREND_UP           => 4;

use constant PDP_STEP						=> 300;

# 86400 seconds per day, 365 days a year, 300 second PDP step value
my $data_steps = 86400 * 365 / PDP_STEP;
my %stats = (
  'temp'    => 100,
  'load'    => 0.05,
  'fan'     => 2000,
  'disk'    => 1000000000,
  'disk2'   => 1000000000,
  'w_bytes' => 0,
  'r_bytes' => 0
);

# Jan 1, 2009 00:00:00 PST
my $timestamp = 1230796800;

my $create_cmd = "rrdtool create sysinfo.rrd --start $timestamp --step 300 \\
		DS:load:GAUGE:600:0:U \\
		DS:temperature:GAUGE:600:0:500 \\
		DS:cpu_fan:GAUGE:600:0:U \\
		DS:disk_used:GAUGE:600:0:U \\
		DS:disk_change:DERIVE:600:U:U \\
		DS:disk2_used:GAUGE:600:0:U \\
		DS:disk2_change:DERIVE:600:U:U \\
		DS:bytes_written:COUNTER:600:0:U \\
		DS:bytes_read:COUNTER:600:0:U \\
		RRA:AVERAGE:0.5:1:8928 \\
		RRA:MIN:0.5:1:8928 \\
		RRA:MAX:0.5:1:8928 \\
		RRA:AVERAGE:0.5:3:8640 \\
		RRA:AVERAGE:0.5:12:8760";

print STDOUT "$create_cmd\n";		
`$create_cmd`;

for (my $i=0; $i<$data_steps; $i++) {
	# increment the timestamp
  $timestamp += PDP_STEP;
  
  # determine the general trend
  my $trend = int(rand(TREND_UP + 1));
  
  # depending on the trend, adjust the stats appropriately
  if ($trend == TREND_DOWN) {
    $stats{'temp'} -= int(rand(5)) if $stats{'temp'} >= 70;
    $stats{'load'} -= int(rand(400)) / 100;
    $stats{'fan'} -= int(rand(100)) if $stats{'fan'} >= 1500;
    $stats{'disk'} -= int(rand(10000000));
    $stats{'disk2'} -= int(rand(10000000));
    $stats{'w_bytes'} += int(rand(1000000));
    $stats{'r_bytes'} += int(rand(3000000));
    
    $stats{'load'} = 0.01 if $stats{'load'} <= 0.00;
    $stats{'disk'} = 0 if $stats{'disk'} <= 0;
    $stats{'disk2'} = 0 if $stats{'disk2'} <= 0;
  }
  elsif ($trend == TREND_DOWN_WEAK) {
    $stats{'temp'} -= int(rand(2)) if $stats{'temp'} >= 70;
    $stats{'load'} -= int(rand(100)) / 100;
    $stats{'fan'} -= int(rand(25)) if $stats{'fan'} >= 1500;
    $stats{'disk'} -= int(rand(1000000));
    $stats{'w_bytes'} += int(rand(2000000));
    $stats{'r_bytes'} += int(rand(6000000));
    
    $stats{'load'} = 0.01 if $stats{'load'} <= 0.00;
    $stats{'disk'} = 0 if $stats{'disk'} <= 0;
    $stats{'disk2'} = 0 if $stats{'disk2'} <= 0;
  }
  elsif ($trend == TREND_UP_WEAK) {
    $stats{'temp'} += int(rand(2)) if $stats{'temp'} <= 200;
    $stats{'load'} += int(rand(100)) / 100 if $stats{'load'} <= 100;
    $stats{'fan'} += int(rand(25)) if $stats{'fan'} <= 3500;
    $stats{'disk'} += int(rand(1000000));
    $stats{'disk2'} += int(rand(1000000));
    $stats{'w_bytes'} += int(rand(3000000));
    $stats{'r_bytes'} += int(rand(9000000));
  }
  elsif ($trend == TREND_UP) {
    $stats{'temp'} += int(rand(5)) if $stats{'temp'} <= 200;
    $stats{'load'} += int(rand(300)) / 100 if $stats{'load'} <= 100;
    $stats{'fan'} += int(rand(100)) if $stats{'fan'} <= 3500;
    $stats{'disk'} += int(rand(10000000));
    $stats{'disk2'} += int(rand(10000000));
    $stats{'w_bytes'} += int(rand(4000000));
    $stats{'r_bytes'} += int(rand(12000000));
  }
  
  # update the RRD with the new data
  `rrdtool update sysinfo.rrd $timestamp:$stats{load}:$stats{temp}:$stats{fan}:$stats{disk}:$stats{disk}:$stats{disk2}:$stats{disk2}:$stats{w_bytes}:$stats{r_bytes}`;
}