PHP - Extract Class Name from File

PHP `extract_class_name` from file

<?php

function extract_class_name ($file) {

        // https://stackoverflow.com/questions/7153000/get-class-name-from-file
        // fix: $class = $tokens[$i+2][1];         ---> if (is_array($tokens[$i+2])) $class = $tokens[$i+2][1];                      Avoids 'Uninitialized string offset 1' when using 'static::class'
        // fix: if ($tokens[$j][0] === T_STRING) { ---> if ($tokens[$j][0] === T_STRING || $tokens[$j][0] === T_NAME_QUALIFIED) {    Handle files with sub-namespaces (T_NAME_QUALIFIED PHP 8.0.0+)
        // fix: add: if ($tokens[$j] === ';') break;                                                                                 Class declarations can't contain a semi-colon. Bailing early speeds things up and prevents confusing lines containing '::class' with the class declaration. 


        $fp = fopen($file, 'r');
        $class = $namespace = $buffer = '';
        $i = 0;
        while (!$class) {
            if (feof($fp)) break;

            $buffer .= fread($fp, 512);
            $tokens = token_get_all($buffer);

            if (strpos($buffer, '{') === false) continue;

            for (;$i<count($tokens);$i++) {
                if ($tokens[$i][0] === T_NAMESPACE) {
                    for ($j=$i+1;$j<count($tokens); $j++) {
                        if ($tokens[$j][0] === T_STRING || $tokens[$j][0] === T_NAME_QUALIFIED) {
                            $namespace .= '\\'.$tokens[$j][1];
                        } else if ($tokens[$j] === '{' || $tokens[$j] === ';') {
                            break;
                        }
                    }
                }

                if ($tokens[$i][0] === T_CLASS) {
                    for ($j=$i+1;$j<count($tokens);$j++) {
                        if ($tokens[$j] === ';') break;
                        if ($tokens[$j] === '{') {
                            if (is_array($tokens[$i+2])) $class = $tokens[$i+2][1];
                        }
                    }
                }
            }
        }

        return $namespace ? $namespace . "\\" . $class : $class;

    }