From ebe4415fcfa965e1beb371e5a748477753948b9d Mon Sep 17 00:00:00 2001
From: David Wanjuki <123358258+dwanjuki@users.noreply.github.com>
Date: Tue, 25 Mar 2025 14:33:52 +0300
Subject: [PATCH 1/2] Create stop-members-from-downgrading-level.php

This snippet can be used to prevent members from downgrading their levels on sites with hierarchical levels.

Originally a "make your day" snippet for a customer.

Not MMPU-compatible.
---
 .../stop-members-from-downgrading-level.php   | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 checkout/stop-members-from-downgrading-level.php

diff --git a/checkout/stop-members-from-downgrading-level.php b/checkout/stop-members-from-downgrading-level.php
new file mode 100644
index 0000000..31f0abd
--- /dev/null
+++ b/checkout/stop-members-from-downgrading-level.php
@@ -0,0 +1,63 @@
+<?php
+/**
+ * Define a level hierarchy and stop members from downgrading their membership level
+ *
+ * This recipe is not compatible with sites that allow multiple memberships per user
+ *
+ * title: Stop members downgrading their membership level
+ * layout: snippet
+ * collection: checkout
+ * category: registration-check
+ *
+ * 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.
+ * Read this companion article for step-by-step directions on either method.
+ * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
+ */
+
+function my_pmpro_tiered_levels_prevent_downgrade( $okay ) {
+	// Bail early if something else isn't okay.
+	if ( ! $okay ) {
+		return $okay;
+	}
+
+	// get user's level
+	$member_level = pmpro_getMembershipLevelForUser();
+
+	// If the user doesn't have a membership level carry on with checkout.
+	if ( false === $member_level ) {
+		return $okay;
+	}
+
+	// member's current level ID
+	$member_level_id = $member_level->id;
+
+	// Get level for checkout.
+	$checkout_level = pmpro_getLevelAtCheckout();
+	$checkout_level_id = $checkout_level->id;
+
+	// bail if renewal 
+	if( $checkout_level_id === $member_level_id ) {
+		return $okay;
+	}
+
+	// Specify the level hierarchy, lowest to highest
+	$level_order = array( 1, 2, 3, 4, 5 );
+
+	// figure out where the levels rank, bail if not in level order
+	$checkout_level_rank = array_search( $checkout_level_id, $level_order );
+	$member_level_rank = array_search( $member_level_id, $level_order );
+	if ( false === $checkout_level_rank || false === $member_level_rank ) {
+		return $okay;
+	}
+
+	// are they checking out for a lower level?
+	if( $member_level_rank > $checkout_level_rank ) {
+		$okay = false;
+		// show an error message on checkout page
+		pmpro_setMessage( 'You are not allowed to checkout for this membership level.', 'pmpro_error' );
+	}
+
+	return $okay;
+}
+add_filter( 'pmpro_registration_checks', 'my_pmpro_tiered_levels_prevent_downgrade' );

From 53d65b79cb31ad9d8925c4dc27db3c7aebe59e03 Mon Sep 17 00:00:00 2001
From: Andrew Lima <andrew@arctek.co.za>
Date: Fri, 19 Sep 2025 11:54:35 +0200
Subject: [PATCH 2/2] Minor WPCS and login check.

---
 checkout/stop-members-from-downgrading-level.php | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/checkout/stop-members-from-downgrading-level.php b/checkout/stop-members-from-downgrading-level.php
index 31f0abd..bb8e923 100644
--- a/checkout/stop-members-from-downgrading-level.php
+++ b/checkout/stop-members-from-downgrading-level.php
@@ -1,26 +1,30 @@
 <?php
 /**
  * Define a level hierarchy and stop members from downgrading their membership level
- *
  * This recipe is not compatible with sites that allow multiple memberships per user
  *
  * title: Stop members downgrading their membership level
  * layout: snippet
  * collection: checkout
  * category: registration-check
+ * link: TBD
  *
  * 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.
  * Read this companion article for step-by-step directions on either method.
  * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
  */
-
 function my_pmpro_tiered_levels_prevent_downgrade( $okay ) {
 	// Bail early if something else isn't okay.
 	if ( ! $okay ) {
 		return $okay;
 	}
 
+	// User isn't logged in, let's assume things are okay.
+	if ( ! is_user_logged_in() ) {
+		return $okay;
+	}
+
 	// get user's level
 	$member_level = pmpro_getMembershipLevelForUser();
 
@@ -37,7 +41,7 @@ function my_pmpro_tiered_levels_prevent_downgrade( $okay ) {
 	$checkout_level_id = $checkout_level->id;
 
 	// bail if renewal 
-	if( $checkout_level_id === $member_level_id ) {
+	if ( $checkout_level_id === $member_level_id ) {
 		return $okay;
 	}
 
@@ -52,7 +56,7 @@ function my_pmpro_tiered_levels_prevent_downgrade( $okay ) {
 	}
 
 	// are they checking out for a lower level?
-	if( $member_level_rank > $checkout_level_rank ) {
+	if ( $member_level_rank > $checkout_level_rank ) {
 		$okay = false;
 		// show an error message on checkout page
 		pmpro_setMessage( 'You are not allowed to checkout for this membership level.', 'pmpro_error' );