From b61bcd27caab3ef0689c1f9df0f24bdda6f508b4 Mon Sep 17 00:00:00 2001
From: Armando Dutra <crisdut@outlook.com>
Date: Fri, 24 Mar 2023 10:23:34 -0300
Subject: [PATCH] monitoring funding tx mining

---
 src/bus/ctl.rs                   | 13 +++++++-
 src/channeld/automata/accept.rs  |  8 +++++
 src/channeld/automata/propose.rs |  6 +++-
 src/watchd/runtime.rs            | 16 ++++-----
 src/watchd/worker.rs             | 56 ++++++++++++++++++++++++++------
 5 files changed, 78 insertions(+), 21 deletions(-)

diff --git a/src/bus/ctl.rs b/src/bus/ctl.rs
index 066e3cc..ed988f6 100644
--- a/src/bus/ctl.rs
+++ b/src/bus/ctl.rs
@@ -86,7 +86,7 @@ pub enum CtlMsg {
     /// Reports changes in the mining status for previously requested transaction tracked by an
     /// on-chain service
     #[display("tx_found({0})")]
-    TxFound(TxStatus),
+    TxFound(TxConfirmation),
 
     // Routing & payments
     /// Request to channel daemon to perform payment using provided route
@@ -260,6 +260,17 @@ pub struct TxStatus {
     pub block_pos: Option<BlockPos>,
 }
 
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Display)]
+#[derive(NetworkEncode, NetworkDecode)]
+#[display("{txid}, ...")]
+pub struct TxConfirmation {
+    /// Id of a transaction previously requested to be tracked
+    pub txid: Txid,
+
+    /// number of block confirmations
+    pub confirmations: u32,
+}
+
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Display, NetworkEncode, NetworkDecode)]
 #[display("{client}, {status}")]
 pub struct Report {
diff --git a/src/channeld/automata/accept.rs b/src/channeld/automata/accept.rs
index 0ff70f6..a4e9719 100644
--- a/src/channeld/automata/accept.rs
+++ b/src/channeld/automata/accept.rs
@@ -167,6 +167,14 @@ fn finish_signed(event: Event<BusMsg>, runtime: &mut Runtime) -> Result<ChannelA
                 event.endpoints,
                 LnMsg::FundingSigned(FundingSigned { channel_id, signature: funding.signature }),
             )?;
+
+            debug!("Waiting for funding transaction {} to be mined", funding.funding_txid);
+            let core = runtime.state.channel.constructor();
+            runtime.send_ctl(event.endpoints, ServiceId::Watch, CtlMsg::Track {
+                txid: funding.funding_txid,
+                depth: core.common_params().minimum_depth,
+            })?;
+
             Ok(ChannelAccept::Funded)
         }
         wrong_msg => {
diff --git a/src/channeld/automata/propose.rs b/src/channeld/automata/propose.rs
index b8b5d7e..e7e8d00 100644
--- a/src/channeld/automata/propose.rs
+++ b/src/channeld/automata/propose.rs
@@ -284,7 +284,11 @@ fn complete_funding(
 
     let txid = runtime.state.channel.funding().txid();
     debug!("Waiting for funding transaction {} to be mined", txid);
-    runtime.send_ctl(event.endpoints, ServiceId::Watch, CtlMsg::Track { txid, depth: 0 })?;
+    let core = runtime.state.channel.constructor();
+    runtime.send_ctl(event.endpoints, ServiceId::Watch, CtlMsg::Track {
+        txid,
+        depth: core.common_params().minimum_depth,
+    })?;
 
     Ok(ChannelPropose::Published)
 }
diff --git a/src/watchd/runtime.rs b/src/watchd/runtime.rs
index c0798d3..e00df3a 100644
--- a/src/watchd/runtime.rs
+++ b/src/watchd/runtime.rs
@@ -34,7 +34,7 @@ pub fn run(config: Config) -> Result<(), Error> {
     rx.bind("inproc://electrum-bridge")?;
 
     let (sender, receiver) = mpsc::channel::<ElectrumUpdate>();
-    let electrum_worker = ElectrumWorker::with(sender, &config.electrum_url, 5)?;
+    let electrum_worker = ElectrumWorker::with(sender, &config.electrum_url, 15)?;
 
     debug!("Starting electrum watcher thread");
     let watcher_runtime = WatcherRuntime::with(receiver, tx)?;
@@ -88,16 +88,14 @@ impl WatcherRuntime {
         // TODO: Forward all electrum notifications over the bridge
         // self.send_over_bridge(msg.into()).expect("watcher bridge is halted");
         match msg {
-            ElectrumUpdate::TxBatch(transactions, _) => {
+            ElectrumUpdate::TxConfirmations(transactions, _) => {
                 for transaction in transactions {
-                    self.send_over_bridge(BusMsg::Ctl(CtlMsg::TxFound(crate::bus::TxStatus {
-                        txid: transaction.txid(),
-                        block_pos: None,
-                    })))
-                    .expect("unable forward electrum notifications over the bridge");
+                    self.send_over_bridge(BusMsg::Ctl(CtlMsg::TxFound(transaction)))
+                        .expect("unable forward electrum notifications over the bridge");
                 }
             }
-            ElectrumUpdate::Connecting
+            ElectrumUpdate::TxBatch(..)
+            | ElectrumUpdate::Connecting
             | ElectrumUpdate::Connected
             | ElectrumUpdate::Complete
             | ElectrumUpdate::FeeEstimate(..)
@@ -170,7 +168,7 @@ impl Runtime {
         match request {
             CtlMsg::TxFound(tx_status) => {
                 if let Some((required_height, service_id)) = self.track_list.get(&tx_status.txid) {
-                    if *required_height >= tx_status.block_pos.map(|b| b.pos).unwrap_or_default() {
+                    if *required_height <= tx_status.confirmations {
                         let service_id = service_id.clone();
                         self.untrack(tx_status.txid);
                         match self.electrum_worker.untrack_transaction(tx_status.txid) {
diff --git a/src/watchd/worker.rs b/src/watchd/worker.rs
index 2fea972..39cd1a2 100644
--- a/src/watchd/worker.rs
+++ b/src/watchd/worker.rs
@@ -13,13 +13,16 @@
 
 // TODO: Consider making it part of descriptor wallet onchain library
 
+use std::collections::BTreeMap;
 use std::sync::mpsc;
 use std::thread::{self, JoinHandle};
 use std::time::Duration;
 
-use bitcoin::{Transaction, Txid};
+use bitcoin::{Script, Transaction, Txid};
 use electrum_client::{Client as ElectrumClient, ElectrumApi, HeaderNotification};
 
+use crate::bus::TxConfirmation;
+
 #[derive(Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Hash, Debug, Display, Error, From)]
 #[display("failed electrum watcher channel")]
 #[from(mpsc::SendError<ElectrumCmd>)]
@@ -48,6 +51,9 @@ pub enum ElectrumUpdate {
     #[display("tx_batch(...)")]
     TxBatch(Vec<Transaction>, f32),
 
+    #[display("tx_confirmations(...)")]
+    TxConfirmations(Vec<TxConfirmation>, u32),
+
     #[display("channel_disconnected")]
     ChannelDisconnected,
 
@@ -82,7 +88,6 @@ impl ElectrumWorker {
             .spawn(move || loop {
                 thread::sleep(Duration::from_secs(interval));
                 sender.send(ElectrumCmd::GetTrasactions).expect("Electrum thread is dead");
-                sender.send(ElectrumCmd::PopHeader).expect("Electrum thread is dead")
             })
             .expect("unable to start blockchain watcher pacemaker thread");
 
@@ -190,10 +195,45 @@ impl ElectrumProcessor {
         &mut self,
         txids: &Vec<Txid>,
     ) -> Result<Option<ElectrumUpdate>, electrum_client::Error> {
-        if self.tracks.is_empty() {
+        if self.tracks.is_empty() || txids.is_empty() {
+            return Ok(None);
+        }
+        let transactions = self.client.batch_transaction_get(txids)?;
+        let scripts: Vec<Script> =
+            transactions.into_iter().map(|tx| tx.output[0].script_pubkey.clone()).collect();
+
+        let hist = self.client.batch_script_get_history(&scripts)?;
+
+        let mut items = vec![];
+        hist.into_iter().for_each(|mut item| items.append(&mut item));
+
+        if items.is_empty() {
             return Ok(None);
         }
-        self.client.batch_transaction_get(txids).map(|res| Some(ElectrumUpdate::TxBatch(res, 0.0)))
+
+        let transactions: BTreeMap<Txid, i32> =
+            items.into_iter().map(|h| (h.tx_hash, h.height)).collect();
+
+        let min_height = transactions.clone().into_iter().map(|(_, h)| h).min();
+        let min_height = min_height.unwrap_or_default();
+
+        let block_headers = self.client.block_headers(min_height as usize, 50)?;
+        let block_total = block_headers.headers.len() as i32;
+
+        let confirmations: BTreeMap<Txid, i32> = transactions
+            .into_iter()
+            .filter(|(_, height)| min_height + block_total > height.to_owned())
+            .collect();
+
+        let confirmations: Vec<TxConfirmation> = confirmations
+            .into_iter()
+            .map(|(tx_id, height)| TxConfirmation {
+                txid: tx_id,
+                confirmations: (min_height + block_total - height) as u32,
+            })
+            .collect();
+
+        Ok(Some(ElectrumUpdate::TxConfirmations(confirmations.clone(), confirmations.len() as u32)))
     }
 
     fn track_transaction(
@@ -201,9 +241,7 @@ impl ElectrumProcessor {
         txid: Txid,
     ) -> Result<Option<ElectrumUpdate>, electrum_client::Error> {
         self.tracks.push(txid);
-        self.client
-            .transaction_get(&txid.clone())
-            .map(|res| Some(ElectrumUpdate::TxBatch([res].to_vec(), 0.0)))
+        self.get_transactions(&self.tracks.clone())
     }
 
     fn untrack_transaction(
@@ -212,8 +250,6 @@ impl ElectrumProcessor {
     ) -> Result<Option<ElectrumUpdate>, electrum_client::Error> {
         let index = self.tracks.iter().position(|x| *x == txid).unwrap();
         self.tracks.remove(index);
-        self.client
-            .transaction_get(&txid.clone())
-            .map(|res| Some(ElectrumUpdate::TxBatch([res].to_vec(), 0.0)))
+        self.get_transactions(&self.tracks.clone())
     }
 }