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[friendica.git] / src / Util / Strings.php

diff --git a/src/Util/Strings.php b/src/Util/Strings.php
index 04d676ef57364ac87ad5c37cb3aff83a53afd672..35e7ebe1510c732ccd793e2837297acdbbf666b0 100644 (file)
--- a/src/Util/Strings.php
+++ b/src/Util/Strings.php
@@ -472,4 +472,52 @@ class Strings
 
                return mb_substr($string, 0, $start) . $replacement . mb_substr($string, $start + $length, $string_length - $start - $length);
        }
+
+       /**
+        * Perform a custom function on a text after having escaped blocks matched by the provided regular expressions.
+        * Only full matches are used, capturing group are ignored.
+        *
+        * To change the provided text, the callback function needs to return it and this function will return the modified
+        * version as well after having restored the escaped blocks.
+        *
+        * @param string   $text
+        * @param string   $regex
+        * @param callable $callback
+        * @return string
+        * @throws \Exception
+        */
+       public static function performWithEscapedBlocks(string $text, string $regex, callable $callback)
+       {
+               // Enables nested use
+               $executionId = random_int(PHP_INT_MAX / 10, PHP_INT_MAX);
+
+               $blocks = [];
+
+               $text = preg_replace_callback($regex,
+                       function ($matches) use ($executionId, &$blocks) {
+                               $return = '«block-' . $executionId . '-' . count($blocks) . '»';
+
+                               $blocks[] = $matches[0];
+
+                               return $return;
+                       },
+                       $text
+               );
+
+               $text = $callback($text) ?? '';
+
+               // Restore code blocks
+               $text = preg_replace_callback('/«block-' . $executionId . '-([0-9]+)»/iU',
+                       function ($matches) use ($blocks) {
+                               $return = $matches[0];
+                               if (isset($blocks[intval($matches[1])])) {
+                                       $return = $blocks[$matches[1]];
+                               }
+                               return $return;
+                       },
+                       $text
+               );
+
+               return $text;
+       }
 }