Proof of concept Pronamic iDEAL Booking Calendar support.

pronamic-ideal-booking.php

<?php

function pronamic_ideal_booking_settings() {
	echo 'Pronamic iDEAL';
}

add_bk_action( 'wpdev_bk_payment_show_tab_in_top_settings', 'pronamic_ideal_booking_settings');

function pronamic_ideal_booking_payment_form( $blank, $booking_id, $summ,$bk_title, $booking_days_count, $booking_type, $bkform, $wp_nonce, $is_deposit ) {
	$output = wpdev_bk_define_payment_form_bank_transfer( $blank, $booking_id, $summ,$bk_title, $booking_days_count, $booking_type, $bkform, $wp_nonce, $is_deposit );

	$output .= 'Pronamic iDEAL';

	return $output;
}

add_bk_filter('wpdev_bk_define_payment_form_bank_transfer', 'pronamic_ideal_booking_payment_form');