Unduplicate more code

api/savedata/update.go

@@ -29,8 +29,6 @@ func Update(uuid []byte, slot int, save any) error {
 	}
 
 	var filename string
-	var buf bytes.Buffer
-
 	switch save := save.(type) {
 	case defs.SystemSaveData: // System
 		if save.TrainerId == 0 && save.SecretId == 0 {
@@ -48,11 +46,6 @@ func Update(uuid []byte, slot int, save any) error {
 
 		filename = "system"
 
-		err = gob.NewEncoder(&buf).Encode(save)
-		if err != nil {
-			return fmt.Errorf("failed to serialize save: %s", err)
-		}
-
 		db.DeleteClaimedAccountCompensations(uuid)
 	case defs.SessionSaveData: // Session
 		if slot < 0 || slot >= defs.SessionSlotCount {
@@ -63,14 +56,15 @@ func Update(uuid []byte, slot int, save any) error {
 		if slot != 0 {
 			filename += strconv.Itoa(slot)
 		}
+	default:
+		return fmt.Errorf("invalid data type")
+	}
 
+	var buf bytes.Buffer
 	err = gob.NewEncoder(&buf).Encode(save)
 	if err != nil {
 		return fmt.Errorf("failed to serialize save: %s", err)
 	}
-	default:
-		return fmt.Errorf("invalid data type")
-	}
 
 	if buf.Len() == 0 {
 		return fmt.Errorf("tried to write empty save file")