#!/usr/bin/perl

# watch.pl

use strict;
use warnings;

use ImgSum;
use LWP::Simple;
use SumDiff;
use Storable;

my @refs = map {retrieve($_)} ('sum-r0.dat', 'sum-r1.dat');

sub min {
    my $mni = 0;
    for my $i(0..$#_)
    {
        if ($_[$i] < $_[$mni])
        {
            $mni = $i
        }
    }
    return $mni;
}

sub getclass {
    my $test = shift;
    my @diffs;
    for my $i(0..$#refs)
    {
        my $diff = SumDiff::diffavg($refs[$i], $test);
        $diffs[$i] = $diff;
        print "Difference to $i: $diff\n";
    }
    return min(@diffs);
}

my $lc = 1;

while (sleep 2)
{
    my $stat = getstore('http://localhost:45005/webcam.jpg', 'current.jpg');
    print "HTTP status: $stat\n";
    my $sum = ImgSum::summary('current.jpg', 4);
    my $cl = getclass($sum);
    print "Likely class: $cl\n";
    if ($lc != $cl)
    {
        system('xscreensaver-command ' .
               ($cl?'-deactivate':'-activate'));
        $lc = $cl;
    }
}