From ca8565de1f009796250cb957340fbf30477a1bc3 Mon Sep 17 00:00:00 2001
From: bcmmbaga <bethuelmbaga12@gmail.com>
Date: Thu, 15 Aug 2024 10:57:45 +0300
Subject: [PATCH] Refactor duplicate diff handling logic

---
 management/server/differs/nameserver.go | 48 +++++++++++++++----------
 management/server/differs/route.go      | 23 ++----------
 2 files changed, 32 insertions(+), 39 deletions(-)

diff --git a/management/server/differs/nameserver.go b/management/server/differs/nameserver.go
index a190ddb5e..fdae9830e 100644
--- a/management/server/differs/nameserver.go
+++ b/management/server/differs/nameserver.go
@@ -20,28 +20,12 @@ func (d *NameServerComparator) Match(a, b reflect.Value) bool {
 }
 
 func (d *NameServerComparator) Diff(cl *diff.Changelog, path []string, a, b reflect.Value) error {
-	if a.Kind() == reflect.Invalid {
-		cl.Add(diff.CREATE, path, nil, b.Interface())
-		return nil
-	}
-	if b.Kind() == reflect.Invalid {
-		cl.Add(diff.DELETE, path, a.Interface(), nil)
-		return nil
+	if err := handleInvalidKind(cl, path, a, b); err != nil {
+		return err
 	}
 
 	if a.Kind() == reflect.Slice && b.Kind() == reflect.Slice {
-		if a.Len() != b.Len() {
-			cl.Add(diff.UPDATE, append(path, "length"), a.Len(), b.Len())
-			return nil
-		}
-
-		for i := 0; i < min(a.Len(), b.Len()); i++ {
-			err := d.Diff(cl, append(path, fmt.Sprintf("[%d]", i)), a.Index(i), b.Index(i))
-			if err != nil {
-				return err
-			}
-		}
-		return nil
+		return handleSliceKind(d, cl, path, a, b)
 	}
 
 	ns1, ok1 := a.Interface().(nbdns.NameServer)
@@ -62,3 +46,29 @@ func (d *NameServerComparator) Diff(cl *diff.Changelog, path []string, a, b refl
 
 	return nil
 }
+
+func handleInvalidKind(cl *diff.Changelog, path []string, a, b reflect.Value) error {
+	if a.Kind() == reflect.Invalid {
+		cl.Add(diff.CREATE, path, nil, b.Interface())
+		return fmt.Errorf("invalid kind")
+	}
+	if b.Kind() == reflect.Invalid {
+		cl.Add(diff.DELETE, path, a.Interface(), nil)
+		return fmt.Errorf("invalid kind")
+	}
+	return nil
+}
+
+func handleSliceKind(comparator diff.ValueDiffer, cl *diff.Changelog, path []string, a, b reflect.Value) error {
+	if a.Len() != b.Len() {
+		cl.Add(diff.UPDATE, append(path, "length"), a.Len(), b.Len())
+		return nil
+	}
+
+	for i := 0; i < min(a.Len(), b.Len()); i++ {
+		if err := comparator.Diff(cl, append(path, fmt.Sprintf("[%d]", i)), a.Index(i), b.Index(i)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/management/server/differs/route.go b/management/server/differs/route.go
index 7d6efaf64..95eb08882 100644
--- a/management/server/differs/route.go
+++ b/management/server/differs/route.go
@@ -21,29 +21,12 @@ func (d *RouteComparator) Match(a, b reflect.Value) bool {
 }
 
 func (d *RouteComparator) Diff(cl *diff.Changelog, path []string, a, b reflect.Value) error {
-	if a.Kind() == reflect.Invalid {
-		cl.Add(diff.CREATE, path, nil, b.Interface())
-		return nil
-	}
-	if b.Kind() == reflect.Invalid {
-		cl.Add(diff.DELETE, path, a.Interface(), nil)
-		return nil
+	if err := handleInvalidKind(cl, path, a, b); err != nil {
+		return err
 	}
 
-	// Handle slice comparison
 	if a.Kind() == reflect.Slice && b.Kind() == reflect.Slice {
-		if a.Len() != b.Len() {
-			cl.Add(diff.UPDATE, append(path, "length"), a.Len(), b.Len())
-			return nil
-		}
-
-		for i := 0; i < min(a.Len(), b.Len()); i++ {
-			err := d.Diff(cl, append(path, fmt.Sprintf("[%d]", i)), a.Index(i), b.Index(i))
-			if err != nil {
-				return err
-			}
-		}
-		return nil
+		return handleSliceKind(d, cl, path, a, b)
 	}
 
 	route1, ok1 := a.Interface().(*nbroute.Route)