cli: Add cli command to pay offer

src/cli.rs

@@ -1,6 +1,11 @@
+use bitcoin::secp256k1::PublicKey;
 use clap::{Parser, Subcommand};
+use lndk::lnd::{get_lnd_client, string_to_network, LndCfg};
 use lndk::lndk_offers::decode;
+use lndk::{Cfg, LndkOnionMessenger, OfferHandler};
 use std::ffi::OsString;
+use std::str::FromStr;
+use tokio::select;
 
 fn get_cert_path_default() -> OsString {
     home::home_dir()
@@ -60,23 +65,104 @@ enum Commands {
         /// The offer string to decode.
         offer_string: String,
     },
+    /// PayOffer pays a BOLT 12 offer, provided as a 'lno'-prefaced offer string.
+    PayOffer {
+        /// The offer string.
+        offer_string: String,
+
+        /// Amount the user would like to pay.
+        amount: u64,
+    },
 }
 
-fn main() {
+#[tokio::main]
+async fn main() -> Result<(), ()> {
     let args = Cli::parse();
     match args.command {
         Commands::Decode { offer_string } => {
             println!("Decoding offer: {offer_string}.");
             match decode(offer_string) {
-                Ok(offer) => println!("Decoded offer: {:?}.", offer),
+                Ok(offer) => {
+                    println!("Decoded offer: {:?}.", offer);
+                    Ok(())
+                }
                 Err(e) => {
                     println!(
                         "ERROR please provide offer starting with lno. Provided offer is \
                         invalid, failed to decode with error: {:?}.",
                         e
-                    )
+                    );
+                    Err(())
+                }
+            }
+        }
+        Commands::PayOffer {
+            offer_string,
+            amount,
+        } => {
+            let offer = match decode(offer_string) {
+                Ok(offer) => offer,
+                Err(e) => {
+                    println!(
+                        "ERROR: please provide offer starting with lno. Provided offer is \
+                        invalid, failed to decode with error: {:?}.",
+                        e
+                    );
+                    return Err(());
+                }
+            };
+
+            let network = string_to_network(&args.network).map_err(|e| {
+                println!("ERROR: invalid network string: {}", e);
+            })?;
+            let lnd_cfg = LndCfg::new(args.address, args.tls_cert.into(), args.macaroon.into());
+            let mut client = get_lnd_client(lnd_cfg.clone()).map_err(|e| {
+                println!("ERROR: failed to connect to lnd: {}", e);
+            })?;
+
+            let info = client
+                .lightning()
+                .get_info(tonic_lnd::lnrpc::GetInfoRequest {})
+                .await
+                .expect("failed to get info")
+                .into_inner();
+            let pubkey = PublicKey::from_str(&info.identity_pubkey).unwrap();
+
+            let (shutdown, listener) = triggered::trigger();
+            let lndk_cfg = Cfg {
+                lnd: lnd_cfg,
+                log_dir: None,
+                shutdown: shutdown.clone(),
+                listener,
+            };
+
+            let handler = OfferHandler::new();
+            let reply_path = handler
+                .create_reply_path(client.clone(), pubkey)
+                .await
+                .map_err(|e| {
+                    println!("ERROR: failed to create reply path: {}", e);
+                })?;
+            let messenger = LndkOnionMessenger::new(handler);
+            select! {
+                _ = messenger.run(lndk_cfg) => {
+                    println!("ERROR: lndk stopped running before pay offer finished.");
+                },
+                // We wait for ldk2 to receive the onion message.
+                res = messenger.offer_handler.pay_offer(
+                    offer.clone(), Some(amount), network, client, offer.paths()[0].clone(),
+                    Some(reply_path),
+                ) => {
+            match res {
+            Ok(_) => println!("Successfully paid for offer!"),
+                        Err(_) => println!("Error paying for offer."),
+                    }
+
+                    shutdown.trigger();
                 }
             }
+
+            Ok(())
         }
     }
 }