+ /// Pays the [`Bolt12Invoice`] associated with the `payment_id` encoded in its `payer_metadata`.
+ ///
+ /// The invoice's `payer_metadata` is used to authenticate that the invoice was indeed requested
+ /// before attempting a payment. [`Bolt12PaymentError::UnexpectedInvoice`] is returned if this
+ /// fails or if the encoded `payment_id` is not recognized. The latter may happen once the
+ /// payment is no longer tracked because the payment was attempted after:
+ /// - an invoice for the `payment_id` was already paid,
+ /// - one full [timer tick] has elapsed since initially requesting the invoice when paying an
+ /// offer, or
+ /// - the refund corresponding to the invoice has already expired.
+ ///
+ /// To retry the payment, request another invoice using a new `payment_id`.
+ ///
+ /// Attempting to pay the same invoice twice while the first payment is still pending will
+ /// result in a [`Bolt12PaymentError::DuplicateInvoice`].
+ ///
+ /// Otherwise, either [`Event::PaymentSent`] or [`Event::PaymentFailed`] are used to indicate
+ /// whether or not the payment was successful.
+ ///
+ /// [timer tick]: Self::timer_tick_occurred
+ pub fn send_payment_for_bolt12_invoice(&self, invoice: &Bolt12Invoice) -> Result<(), Bolt12PaymentError> {
+ let secp_ctx = &self.secp_ctx;
+ let expanded_key = &self.inbound_payment_key;
+ match invoice.verify(expanded_key, secp_ctx) {
+ Ok(payment_id) => self.send_payment_for_verified_bolt12_invoice(invoice, payment_id),
+ Err(()) => Err(Bolt12PaymentError::UnexpectedInvoice),
+ }
+ }
+
+ fn send_payment_for_verified_bolt12_invoice(&self, invoice: &Bolt12Invoice, payment_id: PaymentId) -> Result<(), Bolt12PaymentError> {