Restrict Email Adress When Using a Specific Discount Code at Checkout By Level

my-pmpro-restrict-email-address-for-discount-code-by-level.php

<?php
/**
 * Require a .edu email address when using a specific discount code at checkout.
 *
 * This recipe checks for a discount code applied via URL or checkout,
 * and blocks checkout if the billing email address does not end in .edu.
 *
 * You can optionally restrict this rule to specific membership levels
 * and/or specific discount codes.
 *
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */

/**
 * Validate that the billing email ends in .edu when a restricted discount code is used.
 *
 * @param bool $continue Whether checkout validation should continue.
 * @return bool True to continue checkout, false to block checkout.
 */
function my_pmpro_require_edu_for_url_discount_code( $continue ) {

	// Only run if PMPro checkout level function exists.
	if ( ! function_exists( 'pmpro_getLevelAtCheckout' ) ) {
		return $continue;
	}

	$level = pmpro_getLevelAtCheckout();
	if ( empty( $level ) || empty( $level->id ) ) {
		return $continue;
	}

	/**
	 * OPTIONAL: Restrict this validation to specific membership levels.
	 *
	 * Update the array below with the level IDs you want to target.
	 * Leave empty to apply to all levels.
	 */
	$restricted_levels = array( 7 ); // UPDATE: Add/remove level IDs as needed.
	if ( ! empty( $restricted_levels ) && ! in_array( intval( $level->id ), $restricted_levels, true ) ) {
		return $continue;
	}

	// Grab discount code from URL if present.
	$url_code = '';
	if ( ! empty( $_GET['pmpro_discount_code'] ) ) {
		$url_code = strtoupper( sanitize_text_field( wp_unslash( $_GET['pmpro_discount_code'] ) ) );
	}

	// Check if PMPro already loaded a discount code onto the level object.
	$level_code = '';
	if ( ! empty( $level->discount_code ) ) {
		$level_code = strtoupper( sanitize_text_field( $level->discount_code ) );
	}

	// Use whichever discount code we have available.
	$code = $url_code ? $url_code : $level_code;

	// Bail if no discount code is being used.
	if ( empty( $code ) ) {
		return $continue;
	}

	/**
	 * OPTIONAL: Restrict this rule to specific discount codes.
	 *
	 * Update the array below with the discount codes you want to target.
	 * Leave empty to apply to all discount codes.
	 */
	$restricted_codes = array( 'STUDENT10' ); // UPDATE: Add/remove codes as needed.
	if ( ! empty( $restricted_codes ) && ! in_array( $code, $restricted_codes, true ) ) {
		return $continue;
	}

	// Bail if email is missing. Default PMPro validation will handle required email fields.
	if ( empty( $_REQUEST['bemail'] ) ) {
		return $continue;
	}

	$email = sanitize_email( wp_unslash( $_REQUEST['bemail'] ) );

	// Require .edu email address.
	if ( ! preg_match( '/\.edu$/i', $email ) ) {
		pmpro_setMessage( 'This discount code is only valid for members using a .edu email address.', 'pmpro_error' );
		return false;
	}

	return $continue;
}
add_filter( 'pmpro_registration_checks', 'my_pmpro_require_edu_for_url_discount_code', 20 );