Automattic\WooCommerce\Internal\Fulfillments

FulfillmentUtils::check_s10_upu_format │ public static │ WC 1.0

Calculate the S10 check digit for UPU tracking numbers.

Method of the class: FulfillmentUtils{}

No Hooks.

Returns

true|false. True if the check digit is valid, false otherwise.

Usage

$result = FulfillmentUtils::check_s10_upu_format( $tracking_number ): bool;

$tracking_number(string) (required)

The tracking number without the check digit.

FulfillmentUtils::check_s10_upu_format() FulfillmentUtils::check s10 upu format code ^{WC 10.3.3}

public static function check_s10_upu_format( string $tracking_number ): bool {
	if ( preg_match( '/^[A-Z]{2}\d{9}[A-Z]{2}$/', $tracking_number ) ) {
		// The tracking number is in the UPU S10 format.
		$tracking_number = substr( $tracking_number, 2, -2 );
	} elseif ( ! preg_match( '/^\d{9}$/', $tracking_number ) ) {
		// Ensure the tracking number is exactly 9 digits.
		return false;
	}

	// Define the weights for the S10 check digit calculation.
	$weights = array( 8, 6, 4, 2, 3, 5, 9, 7 );
	$sum     = 0;

	// Calculate the weighted sum of the digits.
	for ( $i = 0; $i < 8; $i++ ) {
		$sum += $weights[ $i ] * (int) $tracking_number[ $i ];
	}

	// Calculate the check digit.
	$check_digit = 11 - ( $sum % 11 );
	if ( 10 === $check_digit ) {
		$check_digit = 0;
	} elseif ( 11 === $check_digit ) {
		$check_digit = 5;
	}

	// Validate the check digit against the last digit of the tracking number.
	return (int) $tracking_number[8] === $check_digit;
}