<?php

/**
* This is the dynamic loader for the library. It checks whether you have
* the mbstring extension available and includes relevant files
* on that basis, falling back to the native (as in written in PHP) version
* if mbstring is unavailabe.
*
* It's probably easiest to use this, if you don't want to understand
* the dependencies involved, in conjunction with PHP versions etc. At
* the same time, you might get better performance by managing loading
* yourself. The smartest way to do this, bearing in mind performance,
* is probably to "load on demand" - i.e. just before you use these
* functions in your code, load the version you need.
*
* It makes sure the the following functions are available;
* utf8_strlen, utf8_strpos, utf8_strrpos, utf8_substr,
* utf8_strtolower, utf8_strtoupper
* Other functions in the ./native directory depend on these
* six functions being available
* @package utf8
*/

/**
* Put the current directory in this constant
*/
if (!defined('UTF8')) {
    define('UTF8', dirname(__FILE__));
}

/**
* If string overloading is active, it will break many of the
* native implementations. mbstring.func_overload must be set
* to 0, 1 or 4 in php.ini (string overloading disabled).
* Also need to check we have the correct internal mbstring
* encoding
*/
if (extension_loaded('mbstring')) {
    /*
     * Joomla modification - As of PHP 8, the `mbstring.func_overload` configuration has been removed and the
     * MB_OVERLOAD_STRING constant will no longer be present, so this check only runs for PHP 7 and older
     * See https://github.com/php/php-src/commit/331e56ce38a91e87a6fb8e88154bb5bde445b132
     * and https://github.com/php/php-src/commit/97df99a6d7d96a886ac143337fecad775907589a
     * for additional references
     */
    if (PHP_VERSION_ID < 80000 && ((int) ini_get('mbstring.func_overload')) & MB_OVERLOAD_STRING) {
        trigger_error('String functions are overloaded by mbstring', E_USER_ERROR);
    }
    mb_internal_encoding('UTF-8');
}

/**
* Check whether PCRE has been compiled with UTF-8 support
*/
$UTF8_ar = [];
if (preg_match('/^.{1}$/u', "ñ", $UTF8_ar) != 1) {
    trigger_error('PCRE is not compiled with UTF-8 support', E_USER_ERROR);
}
unset($UTF8_ar);


/**
* Load the smartest implementations of utf8_strpos, utf8_strrpos
* and utf8_substr
*/
if (!defined('UTF8_CORE')) {
    if (function_exists('mb_substr')) {
        require_once UTF8 . '/mbstring/core.php';
    } else {
        require_once UTF8 . '/utils/unicode.php';
        require_once UTF8 . '/native/core.php';
    }
}

/**
* Load the native implementation of utf8_substr_replace
*/
require_once UTF8 . '/substr_replace.php';

/**
* You should now be able to use all the other utf_* string functions
*/