C:/xampp/htdocs/moodle/lib/textlib.class.php

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<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

defined('MOODLE_INTERNAL') || die();

function textlib_get_instance() {
    return new textlib();
}


class textlib {

    protected static function typo3() {
        static $typo3cs = null;

        if (isset($typo3cs)) {
            return $typo3cs;
        }

        global $CFG;

        // Required files
        require_once($CFG->libdir.'/typo3/class.t3lib_cs.php');
        require_once($CFG->libdir.'/typo3/class.t3lib_div.php');

        // do not use mbstring or recode because it may return invalid results in some corner cases
        $GLOBALS['TYPO3_CONF_VARS']['SYS']['t3lib_cs_convMethod'] = 'iconv';
        $GLOBALS['TYPO3_CONF_VARS']['SYS']['t3lib_cs_utils'] = 'iconv';

        // Tell Typo3 we are curl enabled always (mandatory since 2.0)
        $GLOBALS['TYPO3_CONF_VARS']['SYS']['curlUse'] = '1';

        // And this directory must exist to allow Typo to cache conversion
        // tables when using internal functions
        make_temp_directory('typo3temp/cs');

        // Make sure typo is using our dir permissions
        $GLOBALS['TYPO3_CONF_VARS']['BE']['folderCreateMask'] = decoct($CFG->directorypermissions);

        // Default mask for Typo
        $GLOBALS['TYPO3_CONF_VARS']['BE']['fileCreateMask'] = $CFG->directorypermissions;

        // This full path constants must be defined too, transforming backslashes
        // to forward slashed because Typo3 requires it.
        define ('PATH_t3lib', str_replace('\\','/',$CFG->libdir.'/typo3/'));
        define ('PATH_typo3', str_replace('\\','/',$CFG->libdir.'/typo3/'));
        define ('PATH_site', str_replace('\\','/',$CFG->tempdir.'/'));
        define ('TYPO3_OS', stristr(PHP_OS,'win')&&!stristr(PHP_OS,'darwin')?'WIN':'');

        $typo3cs = new t3lib_cs();

        return $typo3cs;
    }

    public static function parse_charset($charset) {
        $charset = strtolower($charset);

        // shortcuts so that we do not have to load typo3 on every page

        if ($charset === 'utf8' or $charset === 'utf-8') {
            return 'utf-8';
        }

        if (preg_match('/^(cp|win|windows)-?(12[0-9]{2})$/', $charset, $matches)) {
            return 'windows-'.$matches[2];
        }

        if (preg_match('/^iso-8859-[0-9]+$/', $charset, $matches)) {
            return $charset;
        }

        if ($charset === 'euc-jp') {
            return 'euc-jp';
        }
        if ($charset === 'iso-2022-jp') {
            return 'iso-2022-jp';
        }
        if ($charset === 'shift-jis' or $charset === 'shift_jis') {
            return 'shift_jis';
        }
        if ($charset === 'gb2312') {
            return 'gb2312';
        }
        if ($charset === 'gb18030') {
            return 'gb18030';
        }

        // fallback to typo3
        return self::typo3()->parse_charset($charset);
    }

    public static function convert($text, $fromCS, $toCS='utf-8') {
        $fromCS = self::parse_charset($fromCS);
        $toCS   = self::parse_charset($toCS);

        $text = (string)$text; // we can work only with strings

        if ($text === '') {
            return '';
        }

        $result = iconv($fromCS, $toCS.'//TRANSLIT', $text);

        if ($result === false or $result === '') {
            // note: iconv is prone to return empty string when invalid char encountered, or false if encoding unsupported
            $oldlevel = error_reporting(E_PARSE);
            $result = self::typo3()->conv($text, $fromCS, $toCS);
            error_reporting($oldlevel);
        }

        return $result;
    }

    public static function substr($text, $start, $len=null, $charset='utf-8') {
        $charset = self::parse_charset($charset);

        if ($charset === 'utf-8') {
            if (function_exists('mb_substr')) {
                // this is much faster than iconv - see MDL-31142
                if ($len === null) {
                    $oldcharset = mb_internal_encoding();
                    mb_internal_encoding('UTF-8');
                    $result = mb_substr($text, $start);
                    mb_internal_encoding($oldcharset);
                    return $result;
                } else {
                    return mb_substr($text, $start, $len, 'UTF-8');
                }

            } else {
                if ($len === null) {
                    $len = iconv_strlen($text, 'UTF-8');
                }
                return iconv_substr($text, $start, $len, 'UTF-8');
            }
        }

        $oldlevel = error_reporting(E_PARSE);
        if ($len === null) {
            $result = self::typo3()->substr($charset, $text, $start);
        } else {
            $result = self::typo3()->substr($charset, $text, $start, $len);
        }
        error_reporting($oldlevel);

        return $result;
    }

    public static function strlen($text, $charset='utf-8') {
        $charset = self::parse_charset($charset);

        if ($charset === 'utf-8') {
            if (function_exists('mb_strlen')) {
                return mb_strlen($text, 'UTF-8');
            } else {
                return iconv_strlen($text, 'UTF-8');
            }
        }

        $oldlevel = error_reporting(E_PARSE);
        $result = self::typo3()->strlen($charset, $text);
        error_reporting($oldlevel);

        return $result;
    }

    public static function strtolower($text, $charset='utf-8') {
        $charset = self::parse_charset($charset);

        if ($charset === 'utf-8' and function_exists('mb_strtolower')) {
            return mb_strtolower($text, 'UTF-8');
        }

        $oldlevel = error_reporting(E_PARSE);
        $result = self::typo3()->conv_case($charset, $text, 'toLower');
        error_reporting($oldlevel);

        return $result;
    }

    public static function strtoupper($text, $charset='utf-8') {
        $charset = self::parse_charset($charset);

        if ($charset === 'utf-8' and function_exists('mb_strtoupper')) {
            return mb_strtoupper($text, 'UTF-8');
        }

        $oldlevel = error_reporting(E_PARSE);
        $result = self::typo3()->conv_case($charset, $text, 'toUpper');
        error_reporting($oldlevel);

        return $result;
    }

    public static function strpos($haystack, $needle, $offset=0) {
        if (function_exists('mb_strpos')) {
            return mb_strpos($haystack, $needle, $offset, 'UTF-8');
        } else {
            return iconv_strpos($haystack, $needle, $offset, 'UTF-8');
        }
    }

    public static function strrpos($haystack, $needle) {
        if (function_exists('mb_strpos')) {
            return mb_strrpos($haystack, $needle, null, 'UTF-8');
        } else {
            return iconv_strrpos($haystack, $needle, 'UTF-8');
        }
    }

    public static function specialtoascii($text, $charset='utf-8') {
        $charset = self::parse_charset($charset);
        $oldlevel = error_reporting(E_PARSE);
        $result = self::typo3()->specCharsToASCII($charset, $text);
        error_reporting($oldlevel);
        return $result;
    }

    public static function encode_mimeheader($text, $charset='utf-8') {
        if (empty($text)) {
            return (string)$text;
        }
        // Normalize charset
        $charset = self::parse_charset($charset);
        // If the text is pure ASCII, we don't need to encode it
        if (self::convert($text, $charset, 'ascii') == $text) {
            return $text;
        }
        // Although RFC says that line feed should be \r\n, it seems that
        // some mailers double convert \r, so we are going to use \n alone
        $linefeed="\n";
        // Define start and end of every chunk
        $start = "=?$charset?B?";
        $end = "?=";
        // Accumulate results
        $encoded = '';
        // Max line length is 75 (including start and end)
        $length = 75 - strlen($start) - strlen($end);
        // Multi-byte ratio
        $multilength = self::strlen($text, $charset);
        // Detect if strlen and friends supported
        if ($multilength === false) {
            if ($charset == 'GB18030' or $charset == 'gb18030') {
                while (strlen($text)) {
                    // try to encode first 22 chars - we expect most chars are two bytes long
                    if (preg_match('/^(([\x00-\x7f])|([\x81-\xfe][\x40-\x7e])|([\x81-\xfe][\x80-\xfe])|([\x81-\xfe][\x30-\x39]..)){1,22}/m', $text, $matches)) {
                        $chunk = $matches[0];
                        $encchunk = base64_encode($chunk);
                        if (strlen($encchunk) > $length) {
                            // find first 11 chars - each char in 4 bytes - worst case scenario
                            preg_match('/^(([\x00-\x7f])|([\x81-\xfe][\x40-\x7e])|([\x81-\xfe][\x80-\xfe])|([\x81-\xfe][\x30-\x39]..)){1,11}/m', $text, $matches);
                            $chunk = $matches[0];
                            $encchunk = base64_encode($chunk);
                        }
                        $text = substr($text, strlen($chunk));
                        $encoded .= ' '.$start.$encchunk.$end.$linefeed;
                    } else {
                        break;
                    }
                }
                $encoded = trim($encoded);
                return $encoded;
            } else {
                return false;
            }
        }
        $ratio = $multilength / strlen($text);
        // Base64 ratio
        $magic = $avglength = floor(3 * $length * $ratio / 4);
        // basic infinite loop protection
        $maxiterations = strlen($text)*2;
        $iteration = 0;
        // Iterate over the string in magic chunks
        for ($i=0; $i <= $multilength; $i+=$magic) {
            if ($iteration++ > $maxiterations) {
                return false; // probably infinite loop
            }
            $magic = $avglength;
            $offset = 0;
            // Ensure the chunk fits in length, reducing magic if necessary
            do {
                $magic -= $offset;
                $chunk = self::substr($text, $i, $magic, $charset);
                $chunk = base64_encode($chunk);
                $offset++;
            } while (strlen($chunk) > $length);
            // This chunk doesn't break any multi-byte char. Use it.
            if ($chunk)
                $encoded .= ' '.$start.$chunk.$end.$linefeed;
        }
        // Strip the first space and the last linefeed
        $encoded = substr($encoded, 1, -strlen($linefeed));

        return $encoded;
    }

    public static function entities_to_utf8($str, $htmlent=true) {
        static $trans_tbl; // Going to use static transliteration table

        // Replace numeric entities
        $result = preg_replace('~&#x([0-9a-f]+);~ei', 'textlib::code2utf8(hexdec("\\1"))', $str);
        $result = preg_replace('~&#([0-9]+);~e', 'textlib::code2utf8(\\1)', $result);

        // Replace literal entities (if desired)
        if ($htmlent) {
            // Generate/create $trans_tbl
            if (!isset($trans_tbl)) {
                $trans_tbl = array();
                foreach (get_html_translation_table(HTML_ENTITIES) as $val=>$key) {
                    $trans_tbl[$key] = utf8_encode($val);
                }
            }
            $result = strtr($result, $trans_tbl);
        }
        // Return utf8-ised string
        return $result;
    }

    public static function utf8_to_entities($str, $dec=false, $nonnum=false) {
        // Avoid some notices from Typo3 code
        $oldlevel = error_reporting(E_PARSE);
        if ($nonnum) {
            $str = self::typo3()->entities_to_utf8($str, true);
        }
        $result = self::typo3()->utf8_to_entities($str);
        if ($dec) {
            $result = preg_replace('/&#x([0-9a-f]+);/ie', "'&#'.hexdec('$1').';'", $result);
        }
        // Restore original debug level
        error_reporting($oldlevel);
        return $result;
    }

    public static function trim_utf8_bom($str) {
        $bom = "\xef\xbb\xbf";
        if (strpos($str, $bom) === 0) {
            return substr($str, strlen($bom));
        }
        return $str;
    }

    public static function get_encodings() {
        $encodings = array();
        $encodings['UTF-8'] = 'UTF-8';
        $winenc = strtoupper(get_string('localewincharset', 'langconfig'));
        if ($winenc != '') {
            $encodings[$winenc] = $winenc;
        }
        $nixenc = strtoupper(get_string('oldcharset', 'langconfig'));
        $encodings[$nixenc] = $nixenc;

        foreach (self::typo3()->synonyms as $enc) {
            $enc = strtoupper($enc);
            $encodings[$enc] = $enc;
        }
        return $encodings;
    }

    public static function code2utf8($num) {
        if ($num < 128) {
            return chr($num);
        }
        if ($num < 2048) {
            return chr(($num >> 6) + 192) . chr(($num & 63) + 128);
        }
        if ($num < 65536) {
            return chr(($num >> 12) + 224) . chr((($num >> 6) & 63) + 128) . chr(($num & 63) + 128);
        }
        if ($num < 2097152) {
            return chr(($num >> 18) + 240) . chr((($num >> 12) & 63) + 128) . chr((($num >> 6) & 63) + 128) . chr(($num & 63) + 128);
        }
        return '';
    }

    public static function strtotitle($text) {
        if (empty($text)) {
            return $text;
        }

        if (function_exists('mb_convert_case')) {
            return mb_convert_case($text, MB_CASE_TITLE, 'UTF-8');
        }

        $text = self::strtolower($text);
        $words = explode(' ', $text);
        foreach ($words as $i=>$word) {
            $length = self::strlen($word);
            if (!$length) {
                continue;

            } else if ($length == 1) {
                $words[$i] = self::strtoupper($word);

            } else {
                $letter = self::substr($word, 0, 1);
                $letter = self::strtoupper($letter);
                $rest   = self::substr($word, 1);
                $words[$i] = $letter.$rest;
            }
        }
        return implode(' ', $words);
    }

    public static function asort(array &$arr, $sortflag = null) {
        debugging('textlib::asort has been superseeded by collatorlib::asort please upgrade your code to use that', DEBUG_DEVELOPER);
        collatorlib::asort($arr, $sortflag);
    }
}

abstract class collatorlib {

    protected static $collator = null;

    protected static $locale = null;

    protected static function ensure_collator_available() {
        global $CFG;

        $locale = get_string('locale', 'langconfig');
        if (is_null(self::$collator) || $locale != self::$locale) {
            self::$collator = false;
            self::$locale = $locale;
            if (class_exists('Collator', false)) {
                $collator = new Collator($locale);
                if (!empty($collator) && $collator instanceof Collator) {
                    // Check for non fatal error messages. This has to be done immediately
                    // after instantiation as any further calls to collation will cause
                    // it to reset to 0 again (or another error code if one occurred)
                    $errorcode = $collator->getErrorCode();
                    $errormessage = $collator->getErrorMessage();
                    // Check for an error code, 0 means no error occurred
                    if ($errorcode !== 0) {
                        // Get the actual locale being used, e.g. en, he, zh
                        $localeinuse = $collator->getLocale(Locale::ACTUAL_LOCALE);
                        // Check for the common fallback warning error codes. If this occurred
                        // there is normally little to worry about:
                        // - U_USING_DEFAULT_WARNING (127)  - default fallback locale used (pt => UCA)
                        // - U_USING_FALLBACK_WARNING (128) - fallback locale used (de_CH => de)
                        // (UCA: Unicode Collation Algorithm http://unicode.org/reports/tr10/)
                        if ($errorcode === -127 || $errorcode === -128) {
                            // Check if the locale in use is UCA default one ('root') or
                            // if it is anything like the locale we asked for
                            if ($localeinuse !== 'root' && strpos($locale, $localeinuse) !== 0) {
                                // The locale we asked for is completely different to the locale
                                // we have received, let the user know via debugging
                                debugging('Invalid locale: "' . $locale . '", with warning (not fatal) "' . $errormessage .
                                    '", falling back to "' . $collator->getLocale(Locale::VALID_LOCALE) . '"');
                            } else {
                                // Nothing to do here, this is expected!
                                // The Moodle locale setting isn't what the collator expected but
                                // it is smart enough to match the first characters of our locale
                                // to find the correct locale or to use UCA collation
                            }
                        } else {
                            // We've recieved some other sort of non fatal warning - let the
                            // user know about it via debugging.
                            debugging('Problem with locale: "' . $locale . '", with message "' . $errormessage .
                                '", falling back to "' . $collator->getLocale(Locale::VALID_LOCALE) . '"');
                        }
                    }
                    // Store the collator object now that we can be sure it is in a workable condition
                    self::$collator = $collator;
                } else {
                    // Fatal error while trying to instantiate the collator... something went wrong
                    debugging('Error instantiating collator for locale: "' . $locale . '", with error [' .
                        intl_get_error_code() . '] ' . intl_get_error_message($collator));
                }
            }
        }
        return (self::$collator instanceof Collator);
    }

    public static function asort(array &$arr, $sortflag = null) {
        if (self::ensure_collator_available()) {
            if (!isset($sortflag)) {
                $sortflag = Collator::SORT_REGULAR;
            }
            self::$collator->asort($arr, $sortflag);
            return;
        }
        asort($arr, SORT_LOCALE_STRING);
    }

    public static function compare($str1, $str2) {
        if (self::ensure_collator_available()) {
            return self::$collator->compare($str1, $str2);
        }
        return strcmp($str1, $str2);
    }

    public static function asort_objects_by_property(array &$objects, $property) {
        $comparison = new collatorlib_property_comparison($property);
        return uasort($objects, array($comparison, 'compare'));
    }

    public static function asort_objects_by_method(array &$objects, $method) {
        $comparison = new collatorlib_method_comparison($method);
        return uasort($objects, array($comparison, 'compare'));
    }
}

abstract class collatorlib_comparison {
    public abstract function compare($a, $b);
}

class collatorlib_property_comparison extends collatorlib_comparison {

    protected $property;

    public function __construct($property) {
        $this->property = $property;
    }

    public function compare($obja, $objb) {
        $resulta = $obja->{$this->property};
        $resultb = $objb->{$this->property};
        return collatorlib::compare($resulta, $resultb);
    }
}

class collatorlib_method_comparison extends collatorlib_comparison {

    protected $method;

    public function __construct($method) {
        $this->method = $method;
    }

    public function compare($obja, $objb) {
        $resulta = $obja->{$this->method}();
        $resultb = $objb->{$this->method}();
        return collatorlib::compare($resulta, $resultb);
    }
}