ÿØÿà JFIF 

  
 
  ÿÛ „ 	 ( %"1!%)+...383,7(-.+




-+++--++++---+-+-----+---------------+---+-++7-----ÿÀ  ß â
" 

ÿÄ   

           
 ÿÄ H 
     
 !1AQaq"‘¡2B±ÁÑð#R“Ò Tbr‚²á3csƒ’ÂñDS¢³$CÿÄ 
 


            
ÿÄ %

 
       
!1AQa"23‘ÿÚ 
  ? ôÿ ¨pŸªáÿ —åYõõ\?àÒü©ŠÄï¨pŸªáÿ —åYõõ\?àÓü©ŠÄá 0Ÿªáÿ Ÿå[úƒ	ú®ði~TÁb
qÐ8OÕpÿ ƒOò¤Oè`–RÂáœá™êi€ßÉ< FtŸI“öÌ8úDf´°å}“¾œ6
öFá°y¥jñÇh†ˆ¢ã/ÃÐ:ªcÈ
"Y¡ðÑl>ÿ ”ÏËte:qž\oäŠe÷󲍷˜HT4&ÿ ÓÐü6ö®¿øþßèô	Ÿ•7Ñi’•j|“ñì>b…þS?*Óôÿ ÓÐü*h¥£ír¶ü UãSç‚Ÿ[AÐaè[ûª•õ&õj?†Éö+EzP—WeÒírJFt	‘BŒ†Ï‡%#tE Øz ¥OÛ«!1›üä±Í™%º<!vB™'èÔ6´Ña¿«e`Àà0U[-ÂБ4)M÷YK*³hï÷%ÎÎkÇ«m‘-íWŽLsã?nÂ~«†üö®þ¡ÂlÃaÿ ‰ÿ l©°Õ¥ åÜá¿r ºL[Çâ°(Çè'Vãôl8´ÏRÀvLvPõ:…ÙNçF™÷ë>Íãö]°î(–:@<‹ŒÊö×òÆt¦ãº+‡¦%ÌÁ²h´OƒJŒtMÜ>ÀÜÊw3
Y´•牋4ǍýʏTì>œú=Íwhyë,¾Ôò×õ¿ßÊa»«þˆѪQ|%6ž™A	õ%:øj<>É—ÿ Å_ˆCbõ¥š±ý¯Ýƒï…¶|RëócÍf溪“t.СøTÿ *Ä¿-{†çàczůŽ_–^XþŒ±miB[X±d 1,é”zEù»&
î9gœf™9Ð'.;—™i}!ôšåîqêÛ٤ёý£½ÆA–àôe"A$˝Úsäÿ 
÷Û	#°xŸëí(l
	 »ý3—¥5m!
rt`†0~'j2(]S¦¦kv,ÚÇl¦øJA£Šƒ
J3E8ÙiŽ:cÉžúeZ°€¯\®kÖ(79«Ž:¯X”¾³Š&¡* ….‰Ž(ÜíŸ2¥ª‡×Hi²TF¤ò[¨íÈRëÉ䢍mgÑ.Ÿ<öäS0í„ǹÁU´f#Vß;Õ–…P@3ío<ä-±»Ž.L|kªÀê›fÂ6@»eu‚|ÓaÞÆŸ…¨ááå>åŠ?cKü6ùTÍÆ”†sĤÚ;H2RÚ†õ\Ö·Ÿn'¾ ñ#ºI¤Å´%çÁ­‚â7›‹qT3Iï¨Ö
Ú5I7Ë!ÅOóŸ¶øÝñØôת¦$Tcö‘[«Ö³šÒ';Aþ ¸èíg
A2Z
"i¸vdÄ÷.iõ®§)¿]¤À†–‡É&ä{V¶iŽ”.Ó×Õÿ û?h¬Mt–íª[ÿ Ñÿ ÌV(í}=ibÔ¡›¥¢±b
 Lô¥‡piη_Z<‡z§èŒ)iÖwiÇ 2hÙ3·=’d÷8éŽ1¦¸c¤µ€7›7Ø	ð\á)}	¹fËí›pAÃL%âc2 í§æQz¿;T8sæ°qø)QFMð‰XŒÂ±
N¢aF¨…8¯!U		Z©RÊ ÖPVÄÀÍin™Ì-GˆªÅËŠ›•zË}º±ŽÍFò¹}Uw×#ä5B¤{î}Ð<ÙD
é©¤&‡ïDbàÁôMÁ.<?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/>.
 // 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/>.

/**
 * This is a PHP library that handles calling reCAPTCHA v2.
 *
 *    - Documentation
 *          {@link https://developers.google.com/recaptcha/docs/display}
 *    - Get a reCAPTCHA API Key
 *          {@link https://www.google.com/recaptcha/admin}
 *    - Discussion group
 *          {@link http://groups.google.com/group/recaptcha}
 *
 * @package core
 * @copyright 2018 Jeff Webster
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

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

/**
 * The reCAPTCHA URL's
 */
define('RECAPTCHA_API_URL', 'https://www.recaptcha.net/recaptcha/api.js');
define('RECAPTCHA_VERIFY_URL', 'https://www.recaptcha.net/recaptcha/api/siteverify');

/**
 * Returns the language code the reCAPTCHA element should use.
 * Google reCAPTCHA uses different language codes than Moodle so we must convert.
 * https://developers.google.com/recaptcha/docs/language
 *
 * @param string $lang Language to use. If not provided, get current language.
 * @return string A language code
 */
function recaptcha_lang($lang = null) {

    if (empty($lang)) {
        $lang = current_language();
    }

    $glang = $lang;
    switch ($glang) {
        case 'en':
            $glang = 'en-GB';
            break;
        case 'en_us':
            $glang = 'en';
            break;
        case 'zh_cn':
            $glang = 'zh-CN';
            break;
        case 'zh_tw':
            $glang = 'zh-TW';
            break;
        case 'fr_ca':
            $glang = 'fr-CA';
            break;
        case 'pt_br':
            $glang = 'pt-BR';
            break;
        case 'he':
            $glang = 'iw';
            break;
    }
    // For any language code that didn't change reduce down to the base language.
    if (($lang === $glang) and (strpos($lang, '_') !== false)) {
        list($glang, $trash) = explode('_', $lang, 2);
    }
    return $glang;
}

/**
 * Gets the challenge HTML
 * This is called from the browser, and the resulting reCAPTCHA HTML widget
 * is embedded within the HTML form it was called from.
 *
 * @param string $apiurl URL for reCAPTCHA API
 * @param string $pubkey The public key for reCAPTCHA
 * @param string $lang Language to use. If not provided, get current language.
 * @param bool $compactmode If true, use the compact widget.
 * @return string - The HTML to be embedded in the user's form.
 */
function recaptcha_get_challenge_html($apiurl, $pubkey, $lang = null, bool $compactmode = false) {
    global $CFG, $PAGE;

    // To use reCAPTCHA you must have an API key.
    if ($pubkey === null || $pubkey === '') {
        return get_string('getrecaptchaapi', 'auth');
    }

    $jscode = "
        var recaptchacallback = function() {
            grecaptcha.render('recaptcha_element', {
              'sitekey' : '$pubkey'
            });
        }";

    $lang = recaptcha_lang($lang);
    $apicode = "\n<script type=\"text/javascript\" ";
    $apicode .= "src=\"$apiurl?onload=recaptchacallback&render=explicit&hl=$lang\" async defer>";
    $apicode .= "</script>\n";

    $return = html_writer::script($jscode, '');
    $return .= html_writer::div('', 'recaptcha_element', [
        'id' => 'recaptcha_element',
        'data-size' => ($compactmode ? 'compact' : 'normal'),
    ]);
    $return .= $apicode;

    return $return;
}

/**
 * Calls an HTTP POST function to verify if the user's response was correct
 *
 * @param string $verifyurl URL for reCAPTCHA verification
 * @param string $privkey The private key for reCAPTCHA
 * @param string $remoteip The user's IP
 * @param string $response The response from reCAPTCHA
 * @return array
 */
function recaptcha_check_response($verifyurl, $privkey, $remoteip, $response) {
    global $CFG;
    require_once($CFG->libdir.'/filelib.php');

    // Check response - isvalid boolean, error string.
    $checkresponse = array('isvalid' => false, 'error' => 'check-not-started');

    // To use reCAPTCHA you must have an API key.
    if ($privkey === null || $privkey === '') {
        $checkresponse['isvalid'] = false;
        $checkresponse['error'] = 'no-apikey';
        return $checkresponse;
    }

    // For security reasons, you must pass the remote ip to reCAPTCHA.
    if ($remoteip === null || $remoteip === '') {
        $checkresponse['isvalid'] = false;
        $checkresponse['error'] = 'no-remoteip';
        return $checkresponse;
    }

    // Discard spam submissions.
    if ($response === null || strlen($response) === 0) {
        $checkresponse['isvalid'] = false;
        $checkresponse['error'] = 'incorrect-captcha-sol';
        return $checkresponse;
    }

    $params = array('secret' => $privkey, 'remoteip' => $remoteip, 'response' => $response);
    $curl = new curl();
    $curlresponse = $curl->post($verifyurl, $params);

    if ($curl->get_errno() === 0) {
        $curldata = json_decode($curlresponse);

        if (isset($curldata->success) && $curldata->success === true) {
            $checkresponse['isvalid'] = true;
            $checkresponse['error'] = '';
        } else {
            $checkresponse['isvalid'] = false;
            $checkresponse['error'] = $curldata->{'error-codes'};
        }
    } else {
        $checkresponse['isvalid'] = false;
        $checkresponse['error'] = 'check-failed';
    }
    return $checkresponse;
}