From df6dd30af783b62c4d5e9c6df55808a0ac287d40 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Fri, 18 Jun 2021 13:57:41 -0700
Subject: [PATCH] Revert "routing: no backend call to fetch best block"

This reverts commit cdddaaca75bba03f408991702e30d581df80daad.
---
 routing/router.go | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/routing/router.go b/routing/router.go
index f2100dbe..a4e1ca69 100644
--- a/routing/router.go
+++ b/routing/router.go
@@ -10,7 +10,6 @@ import (
 	"time"
 
 	"github.com/btcsuite/btcd/btcec"
-	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
 	"github.com/davecgh/go-spew/spew"
@@ -489,7 +488,6 @@ func (r *ChannelRouter) Start() error {
 	if err != nil {
 		return err
 	}
-	r.bestHeight = uint32(bestHeight)
 
 	// If the graph has never been pruned, or hasn't fully been created yet,
 	// then we don't treat this as an explicit error.
@@ -565,7 +563,7 @@ func (r *ChannelRouter) Start() error {
 
 		// The graph pruning might have taken a while and there could be
 		// new blocks available.
-		bestHash, bestHeight, err = r.cfg.Chain.GetBestBlock()
+		_, bestHeight, err = r.cfg.Chain.GetBestBlock()
 		if err != nil {
 			return err
 		}
@@ -574,7 +572,7 @@ func (r *ChannelRouter) Start() error {
 		// Before we begin normal operation of the router, we first need
 		// to synchronize the channel graph to the latest state of the
 		// UTXO set.
-		if err := r.syncGraphWithChain(bestHash, bestHeight); err != nil {
+		if err := r.syncGraphWithChain(); err != nil {
 			return err
 		}
 
@@ -706,11 +704,15 @@ func (r *ChannelRouter) Stop() error {
 // the latest UTXO set state. This process involves pruning from the channel
 // graph any channels which have been closed by spending their funding output
 // since we've been down.
-func (r *ChannelRouter) syncGraphWithChain(bestHash *chainhash.Hash,
-	bestHeight int32) error {
-
+func (r *ChannelRouter) syncGraphWithChain() error {
 	// First, we'll need to check to see if we're already in sync with the
 	// latest state of the UTXO set.
+	bestHash, bestHeight, err := r.cfg.Chain.GetBestBlock()
+	if err != nil {
+		return err
+	}
+	r.bestHeight = uint32(bestHeight)
+
 	pruneHash, pruneHeight, err := r.cfg.Graph.PruneTip()
 	if err != nil {
 		switch {
@@ -2200,7 +2202,10 @@ func (r *ChannelRouter) sendPayment(
 
 	// We'll also fetch the current block height so we can properly
 	// calculate the required HTLC time locks within the route.
-	currentHeight := int32(atomic.LoadUint32(&r.bestHeight))
+	_, currentHeight, err := r.cfg.Chain.GetBestBlock()
+	if err != nil {
+		return [32]byte{}, nil, err
+	}
 
 	// Now set up a paymentLifecycle struct with these params, such that we
 	// can resume the payment from the current state.