WooCommerce - Add a "prevent purchase" checkbox to product meta and when checked disallows the product from being purchased and removes add to cart buttons

gistfile1.php

<?php

/**
 * Prevent product from being purchased/added to cart, eg with ?add-to-cart=5735 or otherwise
 */
function sumobi_wc_prevent_purchase_validation( $passed, $product_id ) {

	$prevent_purchase = get_post_meta( $product_id, '_wc_prevent_purchase', true );

	if ( $prevent_purchase ) {
		$passed = false;
		wc_add_notice( __( 'This product cannot be purchased.', 'woocommerce' ), 'error' );
	}

	return $passed;
}
add_filter( 'woocommerce_add_to_cart_validation', 'sumobi_wc_prevent_purchase_validation', 10, 2 );


/**
 * Add prevent purchase checkbox
 */
function sumobi_wc_prevent_purchase_option() {
	global $thepostid;

	woocommerce_wp_checkbox( 
		array( 
			'id'            => 'wc-prevent-purchase', 
			'name'          => '_wc_prevent_purchase',
			'wrapper_class' => '', 
			'label'         => 'Prevent Purchase',
			'cbvalue'       => true,
			'value'         => get_post_meta( $thepostid, '_wc_prevent_purchase', true )
		)
	);

}
add_action( 'woocommerce_product_options_pricing', 'sumobi_wc_prevent_purchase_option' );

/**
 * Save prevent purchase checkbox
 */
function sumobi_wc_save_prevent_purchase_option( $post_id ) {
	
	if ( isset( $_POST['_wc_prevent_purchase'] ) ) {
		update_post_meta( $post_id, '_wc_prevent_purchase', true );
	} else {
		delete_post_meta( $post_id, '_wc_prevent_purchase' );
	}

}
add_action( 'woocommerce_process_product_meta_simple', 'sumobi_wc_save_prevent_purchase_option', 10, 2 );


/**
 * Remove add to cart button
 */
function sumobi_wc_remove_add_to_cart_button() {
	
	if ( ! get_post_meta( get_the_ID(), '_wc_prevent_purchase', true ) ) {
		return;
	}

	remove_action( 'woocommerce_single_product_summary', 'woocommerce_template_single_add_to_cart', 30 );
	remove_action( 'woocommerce_simple_add_to_cart', 'woocommerce_simple_add_to_cart', 30 );
	remove_action( 'woocommerce_grouped_add_to_cart', 'woocommerce_grouped_add_to_cart', 30 );
	remove_action( 'woocommerce_variable_add_to_cart', 'woocommerce_variable_add_to_cart', 30 );
	remove_action( 'woocommerce_external_add_to_cart', 'woocommerce_external_add_to_cart', 30 );
}
add_action( 'template_redirect', 'sumobi_wc_remove_add_to_cart_button' );