Move phantom route hint selection into its own function

diff --git a/lightning-invoice/src/utils.rs b/lightning-invoice/src/utils.rs
index 90d5c626bff4344838421612525a87f7d79022c3..a4b4198818c4bd5a2a7a7bd2f1891f56113097f2 100644 (file)
--- a/lightning-invoice/src/utils.rs
+++ b/lightning-invoice/src/utils.rs
@@ -200,6 +200,35 @@ where
                invoice = invoice.amount_milli_satoshis(amt);
        }
 
+       for route_hint in select_phantom_hints(amt_msat, phantom_route_hints, logger) {
+               invoice = invoice.private_route(route_hint);
+       }
+
+       let raw_invoice = match invoice.build_raw() {
+               Ok(inv) => inv,
+               Err(e) => return Err(SignOrCreationError::CreationError(e))
+       };
+       let hrp_str = raw_invoice.hrp.to_string();
+       let hrp_bytes = hrp_str.as_bytes();
+       let data_without_signature = raw_invoice.data.to_base32();
+       let signed_raw_invoice = raw_invoice.sign(|_| node_signer.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
+       match signed_raw_invoice {
+               Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
+               Err(e) => Err(SignOrCreationError::SignError(e))
+       }
+}
+
+/// Utility to select route hints for phantom invoices.
+/// See [`PhantomKeysManager`] for more information on phantom node payments.
+/// 
+/// [`PhantomKeysManager`]: lightning::chain::keysinterface::PhantomKeysManager
+fn select_phantom_hints<L: Deref>(amt_msat: Option<u64>, phantom_route_hints: Vec<PhantomRouteHints>,
+       logger: L) -> Vec<RouteHint>
+where
+       L::Target: Logger,
+{
+       let mut phantom_hints: Vec<RouteHint> = Vec::new();
+
        for PhantomRouteHints { channels, phantom_scid, real_node_pubkey } in phantom_route_hints {
                log_trace!(logger, "Generating phantom route hints for node {}",
                        log_pubkey!(real_node_pubkey));
@@ -223,22 +252,12 @@ where
                                cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
                                htlc_minimum_msat: None,
                                htlc_maximum_msat: None,});
-                       invoice = invoice.private_route(route_hint.clone());
+
+                       phantom_hints.push(route_hint.clone());
                }
        }
 
-       let raw_invoice = match invoice.build_raw() {
-               Ok(inv) => inv,
-               Err(e) => return Err(SignOrCreationError::CreationError(e))
-       };
-       let hrp_str = raw_invoice.hrp.to_string();
-       let hrp_bytes = hrp_str.as_bytes();
-       let data_without_signature = raw_invoice.data.to_base32();
-       let signed_raw_invoice = raw_invoice.sign(|_| node_signer.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
-       match signed_raw_invoice {
-               Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
-               Err(e) => Err(SignOrCreationError::SignError(e))
-       }
+       phantom_hints
 }
 
 #[cfg(feature = "std")]