From 7f66600ef4f2a9070d2123c6c53fef70d2383cf6 Mon Sep 17 00:00:00 2001
From: Jebb <jebb@timble.net>
Date: Thu, 29 Aug 2024 15:04:15 +0800
Subject: [PATCH] #665: Replace usage of utf8_decode and add backward
 compatibility

---
 .../joomlatools/library/filter/ascii.php      |  2 +-
 code/libraries/joomlatools/library/legacy.php | 28 +++++++++++++++++--
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/code/libraries/joomlatools/library/filter/ascii.php b/code/libraries/joomlatools/library/filter/ascii.php
index c0e16cb11..72f9f9649 100644
--- a/code/libraries/joomlatools/library/filter/ascii.php
+++ b/code/libraries/joomlatools/library/filter/ascii.php
@@ -55,7 +55,7 @@ public function sanitize($value)
 
         if ($result === null)
         {
-            $result = htmlentities(utf8_decode($value), ENT_SUBSTITUTE);
+            $result = htmlentities(mb_convert_encoding($value, 'ISO-8859-1', 'UTF-8'));
             $result = preg_replace(
                 array('/&szlig;/','/&(..)lig;/', '/&([aouAOU])uml;/','/&(.)[^;]*;/'),
                 array('ss',"$1","$1".'e',"$1"),
diff --git a/code/libraries/joomlatools/library/legacy.php b/code/libraries/joomlatools/library/legacy.php
index a081ccfc8..9379b5731 100644
--- a/code/libraries/joomlatools/library/legacy.php
+++ b/code/libraries/joomlatools/library/legacy.php
@@ -27,7 +27,7 @@
 {
     function mb_strlen($str)
     {
-        return strlen(utf8_decode($str));
+        return strlen(mb_convert_encoding($str, 'ISO-8859-1', 'UTF-8'));
     }
 }
 
@@ -61,7 +61,7 @@ function mb_substr($str, $offset, $length = NULL)
         if ($offset < 0) {
 
             // see notes
-            $strlen = strlen(utf8_decode($str));
+            $strlen = strlen(mb_convert_encoding($str, 'ISO-8859-1', 'UTF-8'));
             $offset = $strlen + $offset;
             if ($offset < 0) $offset = 0;
 
@@ -100,7 +100,7 @@ function mb_substr($str, $offset, $length = NULL)
 
             if (!isset($strlen)) {
                 // see notes
-                $strlen = strlen(utf8_decode($str));
+                $strlen = strlen(mb_convert_encoding($str, 'ISO-8859-1', 'UTF-8'));
             }
 
             // another trivial case
@@ -401,3 +401,25 @@ function str_contains($haystack, $needle) {
     }
 }
 
+/**
+ * utf8 encoding/decoding compatibility
+ *
+ * @link https://www.php.net/manual/en/function.utf8-decode.php
+ */
+
+ if (!function_exists('utf8_decode'))
+ {
+     function utf8_decode($string)
+     {
+         return mb_convert_encoding($string, 'ISO-8859-1', 'UTF-8');
+     }
+ }
+
+ if (!function_exists('utf8_encode'))
+ {
+     function utf8_encode($string)
+     {
+         return mb_convert_encoding($string, 'UTF-8', mb_detect_encoding($string));
+     }
+ }
+