03_PINValidation.php

<?php

$name = $_GET['name'];
$gender = $_GET['gender'];
$pin = $_GET['pin']; // 9912164756

$birthDate = substr($pin, 0, 6); // 991216
$birthYear = substr($birthDate, 0, 2); // 99
$birthMonth = substr($birthDate, 2, 2); // 12
$birthDay = substr($birthDate, 4, 2); // 16
$regionID = substr($pin, 6, 3); // 475
$genderID = substr($regionID, 2, 1); // 5
$checksum = substr($pin, 9, 1); // 6

$checksumDigits = str_split(substr($pin, 0, 9));

if (isValidName($name) && isValidGender($gender, $genderID) &&
    isValidMonth($birthMonth) && isValidDay($birthDay) &&
    isValidCheckSum($checksumDigits, $checksum) && isValidPinLength($pin)):
    $result = new stdClass();
    $result->name = $name;
    $result->gender = $gender;
    $result->pin = $pin;
    echo json_encode($result);
else:
    echo "<h2>Incorrect data</h2>";
endif;

function isValidPinLength($pin) {
    $pinLength = strlen($pin);
    if ($pinLength === 10):
        return TRUE;
    else:
        return FALSE;
    endif;
}

function isValidName($name) {
    $nameArr = preg_split('/\s+/', $name);
    if (sizeof($nameArr) === 2):
        return TRUE;
    else:
        return FALSE;
    endif;
}

function isValidMonth($month) {
    if (($month >= 1 && $month <= 12) ||
        ($month >= 21 && $month <= 32) ||
        ($month >= 41 && $month <= 52)):
        return TRUE;
    else:
        return FALSE;
    endif;
}

function isValidDay($day) {
    if ($day >= 1 && $day <= 31):
        return TRUE;
    else:
        return FALSE;
    endif;
}

function isValidGender($gender, $genderID) {
    if (($gender === 'female' && $genderID % 2 === 1) ||
        ($gender === 'male' && $genderID % 2 === 0)):
        return TRUE;
    else:
        return FALSE;
    endif;
}

function isValidCheckSum ($digits, $checksum) {
    $multipliers = array(2, 4, 8, 5, 10, 9, 7, 3, 6);
    $result = 0;
    $remainder = 0;
    for($i = 0; $i < sizeof($digits); $i++):
        $result += $digits[$i] * $multipliers[$i];
    endfor;
    $remainder = $result % 11;
    if (($remainder == $checksum) ||
        ($remainder == 10 && $checksum == 0)):
        return TRUE;
    else:
        return FALSE;
    endif;
}

?>