signup-link.php

<?php 

function leaky_paywall_2checkout_add_signup_link( $payment_options, $level, $level_id ) {

	$output = '';
	
	$settings = get_leaky_paywall_settings();


	$gateways = new Leaky_Paywall_Payment_Gateways();
	$enabled_gateways = $gateways->enabled_gateways;

	if ( in_array( '2checkout', array_keys( $enabled_gateways ) ) ) {
		$output = '<div class="leaky-paywall-payment-button"><a href="' . get_page_link( $settings['page_for_register'] ) . '?level_id=' . $level_id . '">Subscribe</a></div>';
	}

	return $payment_options . $output;

}

add_filter( 'leaky_paywall_subscription_options_payment_options', 'leaky_paywall_2checkout_add_signup_link', 7, 3 );