ItemName.php

ItemName.php

<?php
declare(strict_types=1);

final class ItemName
{
    private $value;

    private function __contruct()
    {}
    
    public static function fromString(string $value): self
    {
        if (!preg_match('~^[a-z0-9]+(\.png|\.jpg)$~is', $value)) {
            throw new DomainException('Input contains invalid characters: ' . $value);
        }
        $itemName = new self();
        $itemName->value = $value;
        return $itemName;
    }

    public function value(): string
    {
        return $this->value;
    }
}