From e17b938ef294c1707b7da5324b2bf4f3632241bc Mon Sep 17 00:00:00 2001
From: denver <skripkonitinc@gmail.com>
Date: Tue, 28 Mar 2023 01:26:29 +0300
Subject: [PATCH] reduce validation code and improve algorithm

---
 osutils/data.go | 68 ++++++++++++-------------------------------------
 1 file changed, 16 insertions(+), 52 deletions(-)

diff --git a/osutils/data.go b/osutils/data.go
index 46cf0da..b9fa4fc 100644
--- a/osutils/data.go
+++ b/osutils/data.go
@@ -10,60 +10,24 @@ func UuidValidate(uuid string) error {
 		return errors.New("uuid length not valid")
 	}
 
-	// validate first 8 octets
-	for i := 0; i < 8; i++ {
-		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
-			return errors.New("uuid first 8 octets not valid")
-		}
-	}
-
-	// validate separator
-	if uuid[8] != '-' {
-		return errors.New("uuid separator not valid")
-	}
-
-	// validate second 4 octets
-	for i := 9; i < 13; i++ {
-		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
-			return errors.New("uuid second 4 octets not valid")
-		}
-	}
-
-	// validate separator
-	if uuid[13] != '-' {
-		return errors.New("uuid separator not valid")
-	}
-
-	// validate third 4 octets
-	for i := 14; i < 18; i++ {
-		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
-			return errors.New("uuid third 4 octets not valid")
-		}
-	}
-
-	// validate separator
-	if uuid[18] != '-' {
-		return errors.New("uuid separator not valid")
-	}
-
-	// validate fourth 4 octets
-	for i := 19; i < 23; i++ {
-		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
-			return errors.New("uuid fourth 4 octets not valid")
-		}
-	}
-
-	// validate separator
-	if uuid[23] != '-' {
-		return errors.New("uuid separator not valid")
-	}
-
-	// validate fourth 4 octets
-	for i := 24; i < 36; i++ {
-		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
-			return errors.New("uuid fifth 12 octets not valid")
+	for i, r := range uuid {
+		switch i {
+		case 8, 13, 18, 23:
+			if r != '-' {
+				return errors.New("uuid separator not valid")
+			}
+			break
+		default:
+			if !isLetter(r) && !unicode.IsDigit(r) {
+				return errors.Errorf("uuid char on %i not valid", i)
+			}
 		}
 	}
 
 	return nil
 }
+
+func isLetter(r rune) bool {
+	l := unicode.ToLower(r)
+	return (l >= 'a' && l <= 'z')
+}