Type Value Object for AIG Identity Service

Type.php

<?php

namespace App\Domain\Identity\ValueObjects;

final class Type
{
    const TURKISH_TYPE = 'TURKISH';

    const FOREIGNER_TYPE = 'FOREIGNER';

    const CORPORATION_TYPE = 'CORPORATION';

    /**
     * @var string
     */
    private $type;

    /**
     * @param string $number
     */
    public function __construct(string $number)
    {
        $this->validate($number);
    }

    /**
     * @param string $number
     * @return bool
     */
    private function validate(string $number): bool
    {
        if (strlen($number) === 11 && true === $this->validateIdentityNumber($number)) {
            $this->type = $this->findIdentityNumberType($number);
        } elseif (strlen($number) === 10 && true === $this->validateTaxNumber($number)) {
            $this->type = self::CORPORATION_TYPE;
        } else {
            throw new \InvalidArgumentException('Allowed Turkish Identity number size is 11, VAT number size is 10');
        }

        return true;
    }

    /**
     * @param string $number
     * @return string
     */
    private function findIdentityNumberType(string $number): string
    {
        if ($number[0] !== 9) {
            return self::TURKISH_TYPE;
        }

        $this->type = self::FOREIGNER_TYPE;
    }

    /**
     * This method logically validates Turkish Identity number
     *
     * @param string $identityNumber
     * @return bool
     */
    private function validateIdentityNumber(string $identityNumber): bool
    {
        if (!preg_match('/^[1-9]{1}[0-9]{9}[0,2,4,6,8]{1}$/', $identityNumber)) {
            return false;
        }

        $odd = $identityNumber[0] + $identityNumber[2] + $identityNumber[4] + $identityNumber[6] + $identityNumber[8];

        $even = $identityNumber[1] + $identityNumber[3] + $identityNumber[5] + $identityNumber[7];

        $digit10 = ($odd * 7 - $even) % 10;

        $total = ($odd + $even + $identityNumber[9]) % 10;

        if ($digit10 != $identityNumber[9] || $total != $identityNumber[10]) {
            return false;
        }

        return true;
    }

    /**
     * This method logically validates Turkish VAT number
     *
     * @param string $taxNumber
     * @return bool
     */
    private function validateTaxNumber(string $taxNumber): bool
    {
        if (strlen($taxNumber) !== 10) {
            return false;
        }

        $total = 0;
        $checkNum = null;

        for ($i = 0; $i < 9; $i++) {
            $tmp1 = ($taxNumber[$i] + (9 - $i)) % 10;
            $tmp2 = ($tmp1 * (2 ** (9 - $i))) % 9;

            if ($tmp1 !== 0 && $tmp2 === 0) {
                $tmp2 = 9;
            }

            $total += $tmp2;
        }

        if ($total % 10 === 0) {
            $checkNum = 0;
        } else {
            $checkNum = 10 - ($total % 10);
        }

        if ((int)$taxNumber[9] !== $checkNum) {
            return false;
        }

        return true;
    }

    /**
     * @return string
     */
    public function getType(): string
    {
        return $this->type;
    }

    /**
     * @return string
     */
    public function __toString()
    {
        return $this->getType();
    }
}