From 2dd1c0de3d353305b1138fa00bd0af0765985be4 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Fri, 24 Mar 2017 16:15:04 -0700
Subject: [PATCH] lnwallet: adhere to project code-style in restoreStateLogs
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This commit does some minor shuffling around and also adds some
additional comments to the restoreStateLogs method within the channel
state machine. After the latest merge in this area, the code has
diverged slightly from what’s considered typical within the rest of the
codebase.
---
 lnwallet/channel.go | 53 +++++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 21 deletions(-)

diff --git a/lnwallet/channel.go b/lnwallet/channel.go
index 7663e220e..a4ccc5a2a 100644
--- a/lnwallet/channel.go
+++ b/lnwallet/channel.go
@@ -1026,56 +1026,67 @@ func (lc *LightningChannel) restoreStateLogs() error {
 		pastHeight = lc.currentHeight - 1
 	}
 
-	localKey := lc.channelState.OurCommitKey
-	remoteKey := lc.channelState.TheirCommitKey
-	ourDelay := lc.channelState.LocalCsvDelay
-	theirDelay := lc.channelState.RemoteCsvDelay
-
+	// In order to reconstruct the pkScripts on each of the pending HTLC
+	// outputs (if any) we'll need to regenerate the current revocation for
+	// this current un-revoked state.
 	ourRevPreImage, err := lc.channelState.RevocationProducer.AtIndex(lc.currentHeight)
 	if err != nil {
 		return err
 	}
 	ourRevocation := sha256.Sum256(ourRevPreImage[:])
-
 	theirRevocation := lc.channelState.TheirCurrentRevocationHash
 
+	// Additionally, we'll fetch the current sent to commitment keys and
+	// CSV delay values which are also required to fully generate the
+	// scripts.
+	localKey := lc.channelState.OurCommitKey
+	remoteKey := lc.channelState.TheirCommitKey
+	ourDelay := lc.channelState.LocalCsvDelay
+	theirDelay := lc.channelState.RemoteCsvDelay
+
 	var ourCounter, theirCounter uint64
 
+	// TODO(roasbeef): partition entries added based on our current review
+	// an our view of them from the log?
 	for _, htlc := range lc.channelState.Htlcs {
 		// TODO(roasbeef): set isForwarded to false for all? need to
 		// persist state w.r.t to if forwarded or not, or can
 		// inadvertently trigger replays
 
 		// The proper pkScripts for this PaymentDescriptor must be
-		// generated.
+		// generated so we can easily locate them within the commitment
+		// transaction in the future.
 		var ourP2WSH, theirP2WSH []byte
-		timeout := htlc.RefundTimeout
-		rHash := htlc.RHash
-		amt := htlc.Amt
-		isDustLocal := amt < lc.channelState.OurDustLimit
-		isDustRemote := amt < lc.channelState.TheirDustLimit
 
-		// It is unnecessary to generate pkScripts for dust outputs.
+		// If the either outputs is dust from the local or remote
+		// node's perspective, then we don't need to generate the
+		// scripts as we only generate them in order to locate the
+		// outputs within the commitment transaction. As we'll mark
+		// dust with a special output index in the on-disk state
+		// snapshot.
+		isDustLocal := htlc.Amt < lc.channelState.OurDustLimit
+		isDustRemote := htlc.Amt < lc.channelState.TheirDustLimit
 		if !isDustLocal {
-			ourP2WSH, err = lc.genHtlcScript(htlc.Incoming, true, timeout,
-				ourDelay, remoteKey, localKey, ourRevocation, rHash)
+			ourP2WSH, err = lc.genHtlcScript(htlc.Incoming, true,
+				htlc.RefundTimeout, ourDelay, remoteKey,
+				localKey, ourRevocation, htlc.RHash)
 			if err != nil {
 				return err
 			}
 		}
-		// It is unnecessary to generate pkScripts for dust outputs.
 		if !isDustRemote {
-			theirP2WSH, err = lc.genHtlcScript(htlc.Incoming, false, timeout,
-				theirDelay, remoteKey, localKey, theirRevocation, rHash)
+			theirP2WSH, err = lc.genHtlcScript(htlc.Incoming, false,
+				htlc.RefundTimeout, theirDelay, remoteKey,
+				localKey, theirRevocation, htlc.RHash)
 			if err != nil {
 				return err
 			}
 		}
 
 		pd := &PaymentDescriptor{
-			RHash:                 rHash,
-			Timeout:               timeout,
-			Amount:                amt,
+			RHash:                 htlc.RHash,
+			Timeout:               htlc.RefundTimeout,
+			Amount:                htlc.Amt,
 			EntryType:             Add,
 			addCommitHeightRemote: pastHeight,
 			addCommitHeightLocal:  pastHeight,