<?php
/**
 * Various utility functions
 *
 * @category   DMS
 * @package    SeedDMS
 * @license    GPL 2
 * @version    @version@
 * @author     Uwe Steinmann <uwe@steinmann.cx>
 * @copyright  Copyright (C) 2025 Uwe Steinmann
 * @version    Release: @package_version@
 */

namespace Seeddms\Seeddms;

/**
 * Class with various methods
 *
 * @category   DMS
 * @package    SeedDMS
 * @author     Uwe Steinmann <uwe@steinmann.cx>
 * @copyright  Copyright (C) 2025 Uwe Steinmann
 * @version    Release: @package_version@
 */
class Utilities { /* {{{ */

	/**
	 * Recursively remove a directory on disc
	 *
	 * @param string $dir name of directory
	 */
	static public function rrmdir($dir) { /* {{{ */
		if (is_dir($dir)) {
			$objects = scandir($dir);
			foreach ($objects as $object) {
				if ($object != "." && $object != "..") {
					if (filetype($dir."/".$object) == "dir") self::rrmdir($dir."/".$object); else unlink($dir."/".$object);
				}
			}
			reset($objects);
			rmdir($dir);
		}
	} /* }}} */

	/**
	 * Create a random string
	 *
	 * @param integer $n number of chars
	 * @param string $alph alphabet used as source for chars
	 * @return string random string
	 */
	static public function makeRandomString($n, $alph = "0123456789abcdefghijklmnopqrstuvwxyz") { /* {{{ */
		$len = strlen($alph)-1;
		$s = "";
		for ($i = 0; $i != $n; ++$i)
			$s .= $alph[mt_rand(0, $len)];
		return $s;
	} /* }}} */

	/**
	 * Create a real uniqid for cryptographic purposes
	 *
	 * @ return string
	 */
	static public function uniqidReal($lenght = 13) { /* {{{ */
		// uniqid gives 13 chars, but you could adjust it to your needs.
		if (function_exists("random_bytes")) {
			$bytes = random_bytes(ceil($lenght / 2));
		} elseif (function_exists("openssl_random_pseudo_bytes")) {
			$bytes = openssl_random_pseudo_bytes(ceil($lenght / 2));
		} else {
			throw new Exception("no cryptographically secure random function available");
		}
		return substr(bin2hex($bytes), 0, $lenght);
	} /* }}} */

	/**
	 * Return nonce for CSP
	 *
	 * @return string
	 */
	static public function createNonce() { /* {{{ */
		$length = 16;
		$usable = true;
		$bytes = openssl_random_pseudo_bytes($length, $usable);
		if ($usable === false) {
				// weak
				// @TODO do something?
		}
		return base64_encode($bytes);
	} /* }}} */

} /* }}} */

class_alias('Seeddms\Seeddms\Utilities', 'SeedDMS_Utils');