#!/usr/bin/perl

# Usage: ./solar_2.pl forecast.csv profile.csv $power

use DateTime;

my @csv_forecast;
my @csv_profile;

my $line_number = "0";
open (my $fforecast, '<', $ARGV[0]) or die "Failed to open $ARGV[0]";
while ( my $line = <$fforecast>) {

	$line =~ s/\R/\012/;
	chomp ($line);

	my ($power,$timestamp) = (split "," , $line)[0,3];
	${csv_forecast[$line_number]}{"power"} = $power;
	${csv_forecast[$line_number]}{"timestamp"} = $timestamp;

	++$line_number;
}
close ($fforecast);

$line_number = 0;
open (my $fprofile, '<', $ARGV[1]) or die "Failed to open $ARGV[1]";
while ( my $line = <$fprofile>) {

	chomp ($line);

	my ($timestamp,$percentage) = (split "," , $line);
	${csv_profile[$line_number]}{"timestamp"} = $timestamp;
	${csv_profile[$line_number]}{"percentage"} = $percentage;

	++$line_number;
}
close ($fprofile);

# For each 30 minutes period, calculate whether we are going to produce
# more power than we are going to consume (and therefore waste it),
# or whether we are going to consume more power than we produce (and
# therefore have deficit).

my $waste = "0";
my $deficit = "0";
my $produced = "0";

my ( $y,$m,$d,$h,$mt,$sec );
my ( $i,$j );
for ( $i = 1 ; $i < @csv_forecast ; ++$i )  {

	($y,$m,$d) = $csv_forecast[$i]{"timestamp"} =~ /^([\d]{4})\-([\d]{2})\-([\d]{2})/;
	($h,$mt,$sec) = $csv_forecast[$i]{"timestamp"} =~ /T([\d]{2})\:([\d]{2})\:([\d]{2})Z$/;
	unless ( defined ($h) ) { ($h,$mt,$sec) = ( '0', '0', '0') };
	my $forecast_time = DateTime->new(
		year => $y,
		month => $m,
		day => $d,
		hour => $h,
		minute => $mt,
		second => $sec,
		time_zone => 'UTC'
	);
	$forecast_time->set_time_zone('local');

	my $consumption;
	my ( $hour,$minute );
	for ( $j = 1 ; $j < @csv_profile ; ++$j ) {
		($hour,$minute) = $csv_profile[$j]{"timestamp"} =~ /([\d]{2})\:([\d]{2})$/;

		if ( $hour == $forecast_time->hour() and $minute == $forecast_time->minute() ) {
			$consumption = $csv_profile[$j]{"percentage"} * $ARGV[2] * 0.01;
		}

	}
	if ( $consumption > ( $csv_forecast[$i]{"power"} * 0.5 )) {
		$deficit += $consumption - ( $csv_forecast[$i]{"power"} * 0.5 );
	} else {
		$waste += ( $csv_forecast[$i]{"power"} * 0.5 ) - $consumption;
	}

	$produced += $csv_forecast[$i]{"power"} * 0.5;

	# If the day has changed, print information for the day.
	if ( $forecast_time->hour() == "0" and $forecast_time->minute() == "0" ) {
		$forecast_time->subtract( days=> "1");
		print "INFORMATION FOR DATE ".  $forecast_time->date() . "\n";
		print "Total power produced will be $produced kWh\n";
		print "About $deficit kWh will be taken from the grid (deficit)\n";
		print "About $waste kWh will be produced but not used (wasted)\n\n";

		$deficit = 0;
		$waste = 0;
		$produced = 0;
	}
}

exit;