From b4ddc89fb9b84cf130d943e20bbce9d368354294 Mon Sep 17 00:00:00 2001
From: Ryan Cramer <ryan@processwire.com>
Date: Thu, 17 Apr 2025 12:03:53 -0400
Subject: [PATCH] Add support in MarkupRegions for removing class names by
 wildcard. For instance, `<div id="content" class="-uk-width-*"
 pw-append></div>` would remove all class names from #content div starting
 with "uk-width-". Regex patterns are also supported when pattern is identifed
 by `/`, i.e. `<div id="content" class="-/^uk-(text|width).+$/"
 pw-append></div>` would remove all class names from $content starting with
 "uk-text" or "uk-width".

---
 wire/core/WireMarkupRegions.php | 36 +++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/wire/core/WireMarkupRegions.php b/wire/core/WireMarkupRegions.php
index f3190663..bcfc4de1 100644
--- a/wire/core/WireMarkupRegions.php
+++ b/wire/core/WireMarkupRegions.php
@@ -956,14 +956,38 @@ class WireMarkupRegions extends Wire {
 					$classes = explode(' ', $value);
 					$classes = array_merge($tagInfo['classes'], $classes);
 					$classes = array_unique($classes);
-					// identify remove classes
+					$forceAddClasses = [];
+					$removeMatchClasses = [];
+					// identify force add and remove classes
 					foreach($classes as $key => $class) {
-						if(strpos($class, '-') !== 0) continue;
-						$removeClass = ltrim($class, '-');
-						unset($classes[$key]);
-						while(false !== ($k = array_search($removeClass, $classes))) unset($classes[$k]);
+						if(strpos($class, '+') === 0){
+							$class = ltrim($class, '+');
+							$forceAddClasses[$class] = $class;
+							unset($classes[$key]);
+						} else if(strpos($class, '-') === 0) {
+							$removeClass = substr($class, 1);
+							if(strpos($removeClass, '*') !== false) $removeMatchClasses[] = $removeClass;
+							unset($classes[$key]);
+							while(false !== ($k = array_search($removeClass, $classes))) unset($classes[$k]);
+						}
 					}
-					$attrs['class'] = implode(' ', $classes);
+					if(count($classes) && count($removeMatchClasses)) {
+						foreach($removeMatchClasses as $removeClass) {
+							if(strpos($removeClass, '/') === 0) {
+								// already a regex
+								if(strrpos($removeClass, '/') === 0) $removeClass .= '/';
+							} else {
+								// convert wildcard to regex
+								$removeClass = '/^' . str_replace('\\*', '.+', preg_quote($removeClass, '/')) . '$/';
+							}
+							foreach($classes as $key => $class) {
+								if(preg_match($removeClass, $class)) {
+									unset($classes[$key]);
+								}
+							}
+						}
+					}
+					$attrs['class'] = implode(' ', array_merge($forceAddClasses, $classes));
 				} else {
 					// replace
 					$attrs[$name] = $value;