#!/usr/bin/perl
# David Brenner

use strict;
use DBD::mysql;
use DBI();

my $file = "/home/user/gnuplot.dat";

my $dbh = DBI->connect("DBI:mysql:database=windturbine;host=localhost",
  "user", "password",
  {'RaiseError' => 1});

my $sth = $dbh->prepare("SELECT * from windturbine WHERE cur_timestamp >= NOW() - INTERVAL 1 HOUR");

$sth->execute();

open(FILE, ">$file") or die $!;


my $i = 1;
while (my $ref = $sth->fetchrow_hashref()){
  #print "time: $ref->{'cur_timestamp'}, power: $ref->{'power'}\n";
  print FILE "$ref->{'cur_timestamp'} $ref->{'power'}\n";
  $i++;
}

close FILE;
my $date = `date +'%Y-%m-%d-%H:%M:%S'`;
chomp $date;
open (GNUPLOT, "|gnuplot");
print GNUPLOT <<EOPLOT;
set term png small xFFFFFF
set output "/home/user/graphs/hourly-$date.png"
set size 1 ,1
set nokey
set xdata time
set timefmt "%H:%M:%S"
set xlabel "Time"
set ylabel "Watts"
set title "Wind Turbine Power Data For the Past Hour - $date"
plot "$file" using 2:3 
EOPLOT
close GNUPLOT;


# now do it for the past 24 hours, averaging every 10 minutes

my $sth = $dbh->prepare("SELECT * from windturbine WHERE cur_timestamp >= NOW() - INTERVAL 1 DAY");

$sth->execute();

open(FILE, ">$file") or die $!;

my @times = ("00", "10", "20", "30", "40", "50");
my $i = 0;
my $total = 0;
my $num_data = 0;
my $print_ts;
my $first = 1;
while (my $ref = $sth->fetchrow_hashref()){
  my $timestamp = substr($ref->{'cur_timestamp'},14,2);
  #my $val = $times[($i+1)%5];
  #print "$timestamp eq $val; ",($i+1)%5," ",$timestamp eq $val,"\n";
  if( (not $first) and $timestamp eq $times[($i+1)%5]){
    my $avg = $total/$num_data;
    $print_ts = substr($print_ts,0,15) . "0:00";
    print FILE "$print_ts $avg\n";
    $total = 0;
    $num_data = 0;
    $i++;
  }
  else {
    if($first){
      $i = substr($ref->{'cur_timestamp'},14,1);
      #print "$ref->{'cur_timestamp'};; i = $i\n";
      $first = 0;
    }
    $print_ts = $ref->{'cur_timestamp'};
    $total += $ref->{'power'};
    $num_data++;
  }
}
my $avg = $total/$num_data;
print FILE "$print_ts $avg\n";

close FILE;
chomp $date;
open (GNUPLOT, "|gnuplot");
print GNUPLOT <<EOPLOT;
set term png small xFFFFFF
set output "/home/user/graphs/daily-$date.png"
set size 1 ,1
set nokey
set data style line
set xdata time
set timefmt "%Y-%m-%d %H:%M:%S"
set xlabel "Date"
set ylabel "Watts"
set title "Wind Turbine Power Data For the Past 24 Hours - $date"
plot "$file" using 1:3 w lines 1
EOPLOT
close GNUPLOT;

unlink("/home/user/graphs/current-daily.png","/home/user/graphs/current-hourly.png");
symlink("/home/user/graphs/daily-$date.png","/home/user/graphs/current-daily.png");
symlink("/home/user/graphs/hourly-$date.png","/home/user/graphs/current-hourly.png");