xyzshop/helper/mcard/period_card.php

<?php
declare(strict_types=0);

namespace mcard;


class period_card extends card
{
    public function usable(): bool
    {
        $state = $this->state();
        if ($state === STATE_OVER) {
            return false;
        }
        elseif ($state === STATE_USING)
        {
            if ($this->end_time() < time()) {
                return false;
            } else {
                return true;
            }
        }
        else {
            return true;
        }
    }

    public function deduct(int $cent)
    {
        return [$cent, false];
    }

    public function calc(int $cent)
    {
        $price = round($cent * (1 - $this->discount()) / 100, 2);
        return [$cent, false,$price];
    }
}