: $new_label )
		);
	}

	/**
	 * Payment status update.
	 *
	 * @param Payment     $payment      The status updated payment.
	 * @param bool        $can_redirect Whether or not redirects should be performed.
	 * @param string|null $old_status   Old meta status.
	 * @param string      $new_status   New meta status.
	 *
	 * @return void
	 */
	public function log_payment_status_update( $payment, $can_redirect, $old_status, $new_status ) {
		$note = $this->get_payment_status_update_note( $old_status, $new_status );

		$payment->add_note( $note );
	}

	/**
	 * REST API init.
	 *
	 * @link https://developer.wordpress.org/rest-api/extending-the-rest-api/adding-custom-endpoints/
	 * @link https://developer.wordpress.org/reference/hooks/rest_api_init/
	 *
	 * @return void
	 */
	public function rest_api_init() {
		\register_rest_route(
			'pronamic-pay/v1',
			'/payments/(?P<payment_id>\d+)',
			array(
				'methods'             => 'GET',
				'callback'            => array( $this, 'rest_api_payment' ),
				'permission_callback' => function() {
					return \current_user_can( 'edit_payments' );
				},
				'args'                => array(
					'payment_id' => array(
						'description' => __( 'Payment ID.', 'pronamic_ideal' ),
						'type'        => 'integer',
					),
				),
			)
		);

		register_rest_route(
			'pronamic-pay/v1',
			'/gateways/(?P<config_id>\d+)',
			array(
				'methods'             => 'GET',
				'callback'            => array( $this, 'rest_api_gateway' ),
				'permission_callback' => function() {
					return current_user_can( 'manage_options' );
				},
				'args'                => array(
					'config_id'    => array(
						'description' => __( 'Gateway configuration ID.', 'pronamic_ideal' ),
						'type'        => 'integer',
					),
					'gateway_id'   => array(
						'description' => __( 'Gateway ID.', 'pronamic_ideal' ),
						'type'        => 'string',
					),
					'gateway_mode' => array(
						'description' => __( 'Gateway mode.', 'pronamic_ideal' ),
						'type'        => 'string',
					),
				),
			)
		);
	}

	/**
	 * REST API payment.
	 *
	 * @param \WP_REST_Request $request Request.
	 * @return object
	 */
	public function rest_api_payment( \WP_REST_Request $request ) {
		$payment_id = $request->get_param( 'payment_id' );

		$payment = \get_pronamic_payment( $payment_id );

		if ( null === $payment ) {
			return new \WP_Error(
				'pronamic-pay-payment-not-found',
				\sprintf(
					/* translators: %s: payment ID */
					\__( 'Could not find payment with ID `%s`.', 'pronamic_ideal' ),
					$payment_id
				),
				$payment_id
			);
		}

		return $payment->get_json();
	}

	/**
	 * REST API gateway.
	 *
	 * @param \WP_REST_Request $request Request.
	 * @return object
	 */
	public function rest_api_gateway( \WP_REST_Request $request ) {
		$config_id    = $request->get_param( 'config_id' );
		$gateway_id   = $request->get_param( 'gateway_id' );
		$gateway_mode = $request->get_param( 'gateway_mode' );

		// Gateway.
		$args = array(
			'gateway_id'   => $gateway_id,
			'gateway_mode' => $gateway_mode,
		);

		$gateway = Plugin::get_gateway( $config_id, $args );

		if ( empty( $gateway ) ) {
			return new \WP_Error(
				'pronamic-pay-gateway-not-found',
				sprintf(
					/* translators: %s: Gateway configuration ID */
					__( 'Could not find gateway with ID `%s`.', 'pronamic_ideal' ),
					$config_id
				),
				$config_id
			);
		}

		// Settings.
		ob_start();

		require __DIR__ . '/../../views/meta-box-gateway-settings.php';

		$meta_box_settings = ob_get_clean();

		// Object.
		return (object) array(
			'config_id'    => $config_id,
			'gateway_id'   => $gateway_id,
			'gateway_mode' => $gateway_mode,
			'meta_boxes'   => (object) array(
				'settings' => $meta_box_settings,
			),
		);
	}
}