GeoIP-based pricing pages

functions.php

<?php
// !! Don't paste the <?php line above !!

/**
 * Redirect any pricing pages to my country's pricing page
 */
function redirect_pricing_page() {

    $path = $_SERVER['REQUEST_URI'];

    // If the path doesn't contain /pricing-, abort
    if ( ! stristr( '/pricing-', $path ) ) {
        return;
    }

    // If the GeoIp class doesn't exist, abort
    if ( ! class_exists( 'WPEngine\GeoIp' ) ) {
        return;
    }

    $geo = WPEngine\GeoIp::instance();

    if ( 'US' === $geo->country() && '/pricing-usa/' !== $path ) {
        wp_safe_redirect( site_url( 'pricing-usa' ), 301 );
        exit;
    }

    if ( 'GB' === $geo->country() && '/pricing-uk/' !== $path ) {
        wp_safe_redirect( site_url( 'pricing-uk' ), 301 );
        exit;
    }
}

add_action( 'wp', 'redirect_pricing_page' );