#!/usr/bin/env perl

use strict;
use warnings;

use stfl;
use MCE::Hobo 1.831;
use MCE::Shared;
use Time::HiRes qw/sleep/;

my $count1 = MCE::Shared->scalar(10000);
my $count2 = MCE::Shared->scalar(20000);
my $count3 = MCE::Shared->scalar(30000);

my $layout; {
    open my $fh, "<", "example.stfl"
        or die "open error 'example.stfl': $!";

    local $/; $layout = <$fh>;
}

my $f = stfl::create($layout);
my $s = 0;

# MCE::Hobo 1.832 and later releases will set posix_exit
# automatically when present, $INC{'stfl.pm'}.

MCE::Hobo->init( posix_exit => 1 );

sub bg_start {
    unless ($s) {
        mce_async { sleep(0.9), $count1->incr() while 1 };
        mce_async { sleep(0.6), $count2->incr() while 1 };
        mce_async { sleep(0.3), $count3->incr() while 1 };
        $s = 1;
    }
}

sub bg_stop {
    if ($s) {
        $_->exit()->join() for MCE::Hobo->list();
        $s = 0;
    }
}

$f->set('helpmsg', '[ ESC = exit | F1 = start | F2 = stop ]');

bg_start();

while (1) {
    my $event = $f->run(50);

    if ($s) {
        # must stringify in case numeric value
        $f->set('text 1', ''.$count1->get());
        $f->set('text 2', ''.$count2->get());
        $f->set('text 3', ''.$count3->get());
    }

    next unless (defined $event);

    bg_start() if $event eq 'F1';
    bg_stop()  if $event eq 'F2';

    last       if $event eq 'ESC';
}

bg_stop();