php mc repo

<?php
    function sanitize_file_name( $filename ) {
        $filename_raw = $filename;
        $special_chars = array("?", "[", "]", ".", "\\", "=", "<", ">", ":", ";", ",", "'", "\"", "&", "$", "#", "*", "(", ")", "|", "~", "`", "!", "{", "}");
        $filename = str_replace($special_chars, '', $filename);
        $filename = preg_replace('/[\s-]+/', '-', $filename);
        $filename = trim($filename, '.-_');
        return $filename;
    }

    if(isset($_GET['f'])) {
            $mf = sanitize_file_name($_GET['f']);
            if(file_exists("src/" . $mf. ".lua"))  {
                    echo file_get_contents("src/" . $mf. ".lua");
            } else if(file_exists("src/" . $mf)) {
                    echo file_get_contents("src/" . $mf);
            }

    } else if(isset($_GET['p'])) {
            $mf = sanitize_file_name($_GET['p']);
            if(file_exists("src/" . $mf. ".proj"))  {
                    echo file_get_contents("src/" . $mf. ".proj");
                    echo "\n";
            }

    } else if(isset($_GET['v'])) {
            $mf = sanitize_file_name($_GET['v']);
            if (file_exists("src/" . $mf . ".lua")) {
                echo filemtime("src/" . $mf . ".lua");
            }
            else if (file_exists("src/" . $mf . ".proj")) {
                echo filemtime("src/" . $mf . ".proj");
            }
    }
?>