From 6f3b36e17bb2080f6cf74852da03b1b429748780 Mon Sep 17 00:00:00 2001
From: Luke <rohenaz@gmail.com>
Date: Wed, 28 Oct 2020 22:27:18 -0400
Subject: [PATCH] fix index out of range error during bitbus sync

---
 bmap.go | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/bmap.go b/bmap.go
index ef9240a..71f503c 100644
--- a/bmap.go
+++ b/bmap.go
@@ -36,17 +36,20 @@ func NewFromBob(bobTx *bob.Tx) (bmapTx *Tx, err error) {
 func (bTx *Tx) FromBob(bobTx *bob.Tx) (err error) {
 	for _, out := range bobTx.Out {
 		for _, tape := range out.Tape {
-			switch tape.Cell[0].S {
-			case aip.Prefix:
-				bTx.AIP = aip.NewFromTape(tape)
-				bTx.AIP.SetDataFromTape(out.Tape)
-			case bap.Prefix:
-				bTx.BAP, err = bap.NewFromTape(&tape)
-			case magic.Prefix:
-				bTx.MAP, err = magic.NewFromTape(&tape)
-			case b.Prefix:
-				bTx.B = b.New()
-				err = bTx.B.FromTape(tape)
+			if len(tape.Cell) > 0 {
+				prefixData := tape.Cell[0].S
+				switch prefixData {
+				case aip.Prefix:
+					bTx.AIP = aip.NewFromTape(tape)
+					bTx.AIP.SetDataFromTape(out.Tape)
+				case bap.Prefix:
+					bTx.BAP, err = bap.NewFromTape(&tape)
+				case magic.Prefix:
+					bTx.MAP, err = magic.NewFromTape(&tape)
+				case b.Prefix:
+					bTx.B = b.New()
+					err = bTx.B.FromTape(tape)
+				}
 			}
 		}