remove-initial-payment-for-existing-members.php

<?php
/**
 * Remove the initial payment for users who already had a membership level, including free levels,
 * and the checkout level is a recurring billing level.
 * Optionally, only remove the initial payment when the user has paid an initial payment for a previous level.
 *
 * 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_remove_initial_payment_for_existing_members( $level ) {

	/* set to true to only remove initial payment when initial payment has been paid for a previous level. Set to false to remove initial payment if user had any previous level, including false. */
	$require_previous_payment = false;

	if ( ! is_user_logged_in() || 0 === $level->initial_payment || $level->billing_amount <= 0 ) {
		return $level; // bail if user is not logged in or if level doesn't have an initial payment.
	}

	$user_id          = get_current_user_id(); // get user ID.
	$membership_history    = pmpro_getMembershipLevelsForUser( $user_id, true ); // get user's membership level history.

	if ( empty( $membership_history ) ) {
		return $level; // bail if user has no membership level history.
	}

	if ( $require_previous_payment ) {
		$initial_payments = wp_list_pluck( $membership_history, 'initial_payment' ); // get all initial payments.

		if ( ! empty( $initial_payments ) ) {
			foreach ( $initial_payments as $initial_payment ) {
				if ( $initial_payment > 0 ) {
					$level->initial_payment = 0; // set initial payment to 0 if user has paid an initial payment before.
					break;
				}
			}
		}
	} else {
		$level->initial_payment = 0; // set initial payment to 0 if user has had any previous level.
	}

	return $level;
}
add_filter( 'pmpro_checkout_level', 'my_pmpro_remove_initial_payment_for_existing_members', 10, 1 );