/**
 * This function builds the request that must be sent to the tool producer
 *
 * @param object    $instance       Basic LTI instance object
 * @param object    $typeconfig     Basic LTI tool configuration
 * @param object    $course         Course object
 *
 * @return array    $request        Request details
 */
function lti_build_request($instance, $typeconfig, $course) {
    global $USER, $CFG;

    if (empty($instance->cmid)) {
        $instance->cmid = 0;
    }

    $role = lti_get_ims_role($USER, $instance->cmid, $instance->course);

    $locale = $course->lang;
    if ( strlen($locale) < 1 ) {
         $locale = $CFG->lang;
    }

    $requestparams = array(
        'resource_link_id' => $instance->id,
        'resource_link_title' => $instance->name,
        'resource_link_description' => $instance->intro,
        'user_id' => $USER->id,
        'roles' => $role,
        'context_id' => $course->id,
        'context_label' => $course->shortname,
        'context_title' => $course->fullname,
        'launch_presentation_locale' => $locale,
    );

    $placementsecret = $instance->servicesalt;

    if ( isset($placementsecret) ) {
        $sourcedid = json_encode(lti_build_sourcedid($instance->id, $USER->id, null, $placementsecret));
    }

    if ( isset($placementsecret) &&
         ( $typeconfig['acceptgrades'] == LTI_SETTING_ALWAYS ||
         ( $typeconfig['acceptgrades'] == LTI_SETTING_DELEGATE && $instance->instructorchoiceacceptgrades == LTI_SETTING_ALWAYS ) ) ) {
        $requestparams['lis_result_sourcedid'] = $sourcedid;

        //Add outcome service URL
        $serviceurl = new moodle_url('/mod/lti/service.php');
        $serviceurl = $serviceurl->out();

        if ($typeconfig['forcessl'] == '1') {
            $serviceurl = lti_ensure_url_is_https($serviceurl);
        }

        $requestparams['lis_outcome_service_url'] = $serviceurl;
    }

    // Send user's name and email data if appropriate
    if ( $typeconfig['sendname'] == LTI_SETTING_ALWAYS ||
         ( $typeconfig['sendname'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendname == LTI_SETTING_ALWAYS ) ) {
        $requestparams['lis_person_name_given'] =  $USER->firstname;
        $requestparams['lis_person_name_family'] =  $USER->lastname;
        $requestparams['lis_person_name_full'] =  $USER->firstname." ".$USER->lastname;
    }

    if ( $typeconfig['sendemailaddr'] == LTI_SETTING_ALWAYS ||
         ( $typeconfig['sendemailaddr'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendemailaddr == LTI_SETTING_ALWAYS ) ) {
        $requestparams['lis_person_contact_email_primary'] = $USER->email;
    }

    // Concatenate the custom parameters from the administrator and the instructor
    // Instructor parameters are only taken into consideration if the administrator
    // has giver permission
    $customstr = $typeconfig['customparameters'];
    $instructorcustomstr = $instance->instructorcustomparameters;
    $custom = array();
    $instructorcustom = array();
    if ($customstr) {
        $custom = lti_split_custom_parameters($customstr);
    }
    if (!isset($typeconfig['allowinstructorcustom']) || $typeconfig['allowinstructorcustom'] == LTI_SETTING_NEVER) {
        $requestparams = array_merge($custom, $requestparams);
    } else {
        if ($instructorcustomstr) {
            $instructorcustom = lti_split_custom_parameters($instructorcustomstr);
        }
        foreach ($instructorcustom as $key => $val) {
            // Ignore the instructor's parameter
            if (!array_key_exists($key, $custom)) {
                $custom[$key] = $val;
            }
        }
        $requestparams = array_merge($custom, $requestparams);
    }

    // Make sure we let the tool know what LMS they are being called from
    $requestparams["ext_lms"] = "moodle-2";
    $requestparams['tool_consumer_info_product_family_code'] = 'moodle';
    $requestparams['tool_consumer_info_version'] = strval($CFG->version);

//.........这里部分代码省略.........

 public function test_lti_ensure_url_is_https()
 {
     $this->assertEquals('https://moodle.org', lti_ensure_url_is_https('http://moodle.org'));
     $this->assertEquals('https://moodle.org', lti_ensure_url_is_https('moodle.org'));
     $this->assertEquals('https://moodle.org', lti_ensure_url_is_https('https://moodle.org'));
 }

/**
 * This function builds the request that must be sent to the tool producer
 *
 * @param object    $instance       Basic LTI instance object
 * @param array     $typeconfig     Basic LTI tool configuration
 * @param object    $course         Course object
 * @param int|null  $typeid         Basic LTI tool ID
 * @param boolean   $islti2         True if an LTI 2 tool is being launched
 *
 * @return array                    Request details
 */
function lti_build_request($instance, $typeconfig, $course, $typeid = null, $islti2 = false)
{
    global $USER, $CFG;
    if (empty($instance->cmid)) {
        $instance->cmid = 0;
    }
    $role = lti_get_ims_role($USER, $instance->cmid, $instance->course, $islti2);
    $intro = '';
    if (!empty($instance->cmid)) {
        $intro = format_module_intro('lti', $instance, $instance->cmid);
        $intro = html_to_text($intro, 0, false);
        // This may look weird, but this is required for new lines
        // so we generate the same OAuth signature as the tool provider.
        $intro = str_replace("\n", "\r\n", $intro);
    }
    $requestparams = array('resource_link_title' => $instance->name, 'resource_link_description' => $intro, 'user_id' => $USER->id, 'lis_person_sourcedid' => $USER->idnumber, 'roles' => $role, 'context_id' => $course->id, 'context_label' => $course->shortname, 'context_title' => $course->fullname);
    if (!empty($instance->id)) {
        $requestparams['resource_link_id'] = $instance->id;
    }
    if (!empty($instance->resource_link_id)) {
        $requestparams['resource_link_id'] = $instance->resource_link_id;
    }
    if ($course->format == 'site') {
        $requestparams['context_type'] = 'Group';
    } else {
        $requestparams['context_type'] = 'CourseSection';
        $requestparams['lis_course_section_sourcedid'] = $course->idnumber;
    }
    $placementsecret = $instance->servicesalt;
    if (!empty($instance->id) && isset($placementsecret) && ($islti2 || $typeconfig['acceptgrades'] == LTI_SETTING_ALWAYS || $typeconfig['acceptgrades'] == LTI_SETTING_DELEGATE && $instance->instructorchoiceacceptgrades == LTI_SETTING_ALWAYS)) {
        $sourcedid = json_encode(lti_build_sourcedid($instance->id, $USER->id, $placementsecret, $typeid));
        $requestparams['lis_result_sourcedid'] = $sourcedid;
        // Add outcome service URL.
        $serviceurl = new \moodle_url('/mod/lti/service.php');
        $serviceurl = $serviceurl->out();
        $forcessl = false;
        if (!empty($CFG->mod_lti_forcessl)) {
            $forcessl = true;
        }
        if (isset($typeconfig['forcessl']) && $typeconfig['forcessl'] == '1' or $forcessl) {
            $serviceurl = lti_ensure_url_is_https($serviceurl);
        }
        $requestparams['lis_outcome_service_url'] = $serviceurl;
    }
    // Send user's name and email data if appropriate.
    if ($islti2 || $typeconfig['sendname'] == LTI_SETTING_ALWAYS || $typeconfig['sendname'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendname == LTI_SETTING_ALWAYS) {
        $requestparams['lis_person_name_given'] = $USER->firstname;
        $requestparams['lis_person_name_family'] = $USER->lastname;
        $requestparams['lis_person_name_full'] = $USER->firstname . ' ' . $USER->lastname;
        $requestparams['ext_user_username'] = $USER->username;
    }
    if ($islti2 || $typeconfig['sendemailaddr'] == LTI_SETTING_ALWAYS || $typeconfig['sendemailaddr'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendemailaddr == LTI_SETTING_ALWAYS) {
        $requestparams['lis_person_contact_email_primary'] = $USER->email;
    }
    return $requestparams;
}