From ee5d3c72d9dc8ba35f449db16d95adad9cf9943c Mon Sep 17 00:00:00 2001
From: Felicitas Pojtinger <felicitas@pojtinger.com>
Date: Mon, 6 Dec 2021 23:31:55 +0100
Subject: [PATCH] refactor: Drop offset in favor of ignoring the first index

---
 cmd/stbak/cmd/archive.go              |  1 -
 cmd/stbak/cmd/recovery_index.go       |  1 -
 cmd/stbak/cmd/update.go               |  9 ++++---
 pkg/recovery/index.go                 | 37 ++++++++++++---------------
 pkg/utility/{utility.go => keygen.go} |  0
 5 files changed, 22 insertions(+), 26 deletions(-)
 rename pkg/utility/{utility.go => keygen.go} (100%)

diff --git a/cmd/stbak/cmd/archive.go b/cmd/stbak/cmd/archive.go
index 7b9f92b..e9f0c4d 100644
--- a/cmd/stbak/cmd/archive.go
+++ b/cmd/stbak/cmd/archive.go
@@ -173,7 +173,6 @@ var archiveCmd = &cobra.Command{
 			int(lastIndexedBlock),
 			viper.GetBool(overwriteFlag),
 
-			0,
 			func(hdr *tar.Header, i int) error {
 				if len(hdrs) <= i {
 					return errMissingTarHeader
diff --git a/cmd/stbak/cmd/recovery_index.go b/cmd/stbak/cmd/recovery_index.go
index 8d22e39..a4c6624 100644
--- a/cmd/stbak/cmd/recovery_index.go
+++ b/cmd/stbak/cmd/recovery_index.go
@@ -77,7 +77,6 @@ var recoveryIndexCmd = &cobra.Command{
 			viper.GetInt(blockFlag),
 			viper.GetBool(overwriteFlag),
 
-			0,
 			func(hdr *tar.Header, i int) error {
 				return encryption.DecryptHeader(hdr, viper.GetString(encryptionFlag), identity)
 			},
diff --git a/cmd/stbak/cmd/update.go b/cmd/stbak/cmd/update.go
index a3f9814..f1ad5c6 100644
--- a/cmd/stbak/cmd/update.go
+++ b/cmd/stbak/cmd/update.go
@@ -119,13 +119,16 @@ var updateCmd = &cobra.Command{
 			int(lastIndexedBlock),
 			false,
 
-			1,
 			func(hdr *tar.Header, i int) error {
-				if len(hdrs) <= i {
+				if i == 0 {
+					return nil
+				}
+
+				if len(hdrs) <= i-1 {
 					return errMissingTarHeader
 				}
 
-				*hdr = *hdrs[i]
+				*hdr = *hdrs[i-1]
 
 				return nil
 			},
diff --git a/pkg/recovery/index.go b/pkg/recovery/index.go
index 1640674..883b7a0 100644
--- a/pkg/recovery/index.go
+++ b/pkg/recovery/index.go
@@ -32,7 +32,6 @@ func Index(
 	block int,
 	overwrite bool,
 
-	offset int,
 	decryptHeader func(
 		hdr *tar.Header,
 		i int,
@@ -129,18 +128,16 @@ func Index(
 				break
 			}
 
-			if i >= offset {
-				if err := decryptHeader(hdr, i-offset); err != nil {
-					return err
-				}
+			if err := decryptHeader(hdr, i); err != nil {
+				return err
+			}
 
-				if err := verifyHeader(hdr, isRegular); err != nil {
-					return err
-				}
+			if err := verifyHeader(hdr, isRegular); err != nil {
+				return err
+			}
 
-				if err := indexHeader(record, block, hdr, metadataPersister, pipes.Compression, pipes.Encryption); err != nil {
-					return nil
-				}
+			if err := indexHeader(record, block, hdr, metadataPersister, pipes.Compression, pipes.Encryption); err != nil {
+				return nil
 			}
 
 			curr, err := f.Seek(0, io.SeekCurrent)
@@ -215,18 +212,16 @@ func Index(
 				}
 			}
 
-			if i >= offset {
-				if err := decryptHeader(hdr, i-offset); err != nil {
-					return err
-				}
+			if err := decryptHeader(hdr, i); err != nil {
+				return err
+			}
 
-				if err := verifyHeader(hdr, isRegular); err != nil {
-					return err
-				}
+			if err := verifyHeader(hdr, isRegular); err != nil {
+				return err
+			}
 
-				if err := indexHeader(record, block, hdr, metadataPersister, pipes.Compression, pipes.Encryption); err != nil {
-					return nil
-				}
+			if err := indexHeader(record, block, hdr, metadataPersister, pipes.Compression, pipes.Encryption); err != nil {
+				return nil
 			}
 
 			curr = int64(counter.BytesRead)
diff --git a/pkg/utility/utility.go b/pkg/utility/keygen.go
similarity index 100%
rename from pkg/utility/utility.go
rename to pkg/utility/keygen.go