public function __construct(Block $block)
{
$layout = $block->getTimetable()->getLineConfig()->getLayoutConfig();
$extension = new CalendarExtension();
$this->hoursRange = $extension->calendarRange($layout);
// add at least one empty frequency to show empty form
if (count($block->getFrequencies()) == 0) {
$frequency = new Frequency();
$block->setFrequencies(new ArrayCollection(array($frequency)));
}
}
