Validation and normalization of Armenian Phone numbers

phone.php

<?php

/**
 * Class Phone
 */
class Phone {

    /**
     * Phone number
     *
     * @var string
     */
    private $number;

    /**
     * Phone number in local format
     *
     * @var string
     */
    private $number_local;

    /**
     * Phone number in international format
     *
     * @var string
     */
    private $number_international;

    /**
     * Phone check status
     *
     * @var bool
     */
    private $check_status = false;

    /**
     * Constructor
     *
     * @param string $number
     */
    public function __construct($number) {

        // Store phone number
        $this->number = $number;

        // Normalizing number and saving check status
        $this->check_status = $this->normalize_number();
    }

    /**
     * Normalizing phone number
     *
     * @return bool
     */
    private function normalize_number() {

        // Supported careers
        $careers = array(91, 96, 99, 43, 77, 93, 94, 98, 97, 77, 55, 95, 41, 49);

        // Getting phone number
        $number = $this->number;

        // If first to numbers are 00
        if (substr($number, 0, 2) === '00') {

            // Replace with +
            $number = '+' . substr($number, 2);
        }

        // If number is in local format, change it with international format
        if (substr($number, 0, 1) === '0') {

            // Add Armenian code
            $number = '+374' . substr($number, 1);
        }
        elseif (in_array(substr($number, 0, 2), $careers)) {
            // Add Armenian code
            $number = '+374' . $number;
        }

        // Check if number in armenia
        if (substr($number, 0, 4) !== '+374') {
            return false;
        }

        // Getting career code and phone number
        $career = substr($number, 4, 2);
        $phone = substr($number, 6);

        // Length of phone number must be 6
        if (strlen($phone) !== 6) return false;

        // If career not supported
        if (!in_array($career, $careers)) return false;

        // Save phone number
        $this->number_international = $number;
        $this->number_local = '0' . $career . $phone;

        return true;
    }

    /**
     * Getting phone number in local format
     *
     * @return bool|string
     */
    public function get_local() {

        // If phone is wrong, return false
        if ($this->check_phone() === FALSE) return false;

        // Return local number
        return $this->number_local;
    }

    /**
     * Getting phone number in international format
     *
     * @return bool|string
     */
    public function get_international() {

        // If phone is wrong, return false
        if ($this->check_phone() === FALSE) return false;

        // Return international number
        return $this->number_international;
    }

    /**
     * Checking phone
     *
     * @return bool
     */
    public function check_phone() {

        return $this->check_status;
    }
    
}