mod/lti/locallib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16 //
  17 // This file is part of BasicLTI4Moodle
  18 //
  19 // BasicLTI4Moodle is an IMS BasicLTI (Basic Learning Tools for Interoperability)
  20 // consumer for Moodle 1.9 and Moodle 2.0. BasicLTI is a IMS Standard that allows web
  21 // based learning tools to be easily integrated in LMS as native ones. The IMS BasicLTI
  22 // specification is part of the IMS standard Common Cartridge 1.1 Sakai and other main LMS
  23 // are already supporting or going to support BasicLTI. This project Implements the consumer
  24 // for Moodle. Moodle is a Free Open source Learning Management System by Martin Dougiamas.
  25 // BasicLTI4Moodle is a project iniciated and leaded by Ludo(Marc Alier) and Jordi Piguillem
  26 // at the GESSI research group at UPC.
  27 // SimpleLTI consumer for Moodle is an implementation of the early specification of LTI
  28 // by Charles Severance (Dr Chuck) htp://dr-chuck.com , developed by Jordi Piguillem in a
  29 // Google Summer of Code 2008 project co-mentored by Charles Severance and Marc Alier.
  30 //
  31 // BasicLTI4Moodle is copyright 2009 by Marc Alier Forment, Jordi Piguillem and Nikolas Galanis
  32 // of the Universitat Politecnica de Catalunya http://www.upc.edu
  33 // Contact info: Marc Alier Forment granludo @ gmail.com or marc.alier @ upc.edu.
  34
  35 /**
  36  * This file contains the library of functions and constants for the lti module
  37  *
  38  * @package mod_lti
  39  * @copyright  2009 Marc Alier, Jordi Piguillem, Nikolas Galanis
  40  *  marc.alier@upc.edu
  41  * @copyright  2009 Universitat Politecnica de Catalunya http://www.upc.edu
  42  * @author     Marc Alier
  43  * @author     Jordi Piguillem
  44  * @author     Nikolas Galanis
  45  * @author     Chris Scribner
  46  * @copyright  2015 Vital Source Technologies http://vitalsource.com
  47  * @author     Stephen Vickers
  48  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  49  */
  50
  51 defined('MOODLE_INTERNAL') || die;
  52
  53 // TODO: Switch to core oauthlib once implemented - MDL-30149.
  54 use moodle\mod\lti as lti;
  55
  56 require_once($CFG->dirroot.'/mod/lti/OAuth.php');
  57
  58 define('LTI_URL_DOMAIN_REGEX', '/(?:https?:\/\/)?(?:www\.)?([^\/]+)(?:\/|$)/i');
  59
  60 define('LTI_LAUNCH_CONTAINER_DEFAULT', 1);
  61 define('LTI_LAUNCH_CONTAINER_EMBED', 2);
  62 define('LTI_LAUNCH_CONTAINER_EMBED_NO_BLOCKS', 3);
  63 define('LTI_LAUNCH_CONTAINER_WINDOW', 4);
  64 define('LTI_LAUNCH_CONTAINER_REPLACE_MOODLE_WINDOW', 5);
  65
  66 define('LTI_TOOL_STATE_ANY', 0);
  67 define('LTI_TOOL_STATE_CONFIGURED', 1);
  68 define('LTI_TOOL_STATE_PENDING', 2);
  69 define('LTI_TOOL_STATE_REJECTED', 3);
  70 define('LTI_TOOL_PROXY_TAB', 4);
  71
  72 define('LTI_TOOL_PROXY_STATE_CONFIGURED', 1);
  73 define('LTI_TOOL_PROXY_STATE_PENDING', 2);
  74 define('LTI_TOOL_PROXY_STATE_ACCEPTED', 3);
  75 define('LTI_TOOL_PROXY_STATE_REJECTED', 4);
  76
  77 define('LTI_SETTING_NEVER', 0);
  78 define('LTI_SETTING_ALWAYS', 1);
  79 define('LTI_SETTING_DELEGATE', 2);
  80
  81 /**
  82  * Return the launch data required for opening the external tool.
  83  *
  84  * @param  stdClass $instance the external tool activity settings
  85  * @return array the endpoint URL and parameters (including the signature)
  86  * @since  Moodle 3.0
  87  */
  88 function lti_get_launch_data($instance) {
  89     global $PAGE, $CFG;
  90
  91     if (empty($instance->typeid)) {
  92         $tool = lti_get_tool_by_url_match($instance->toolurl, $instance->course);
  93         if ($tool) {
  94             $typeid = $tool->id;
  95         } else {
  96             $typeid = null;
  97         }
  98     } else {
  99         $typeid = $instance->typeid;
 100         $tool = lti_get_type($typeid);
 101     }
 102
 103     if ($typeid) {
 104         $typeconfig = lti_get_type_config($typeid);
 105     } else {
 106         // There is no admin configuration for this tool. Use configuration in the lti instance record plus some defaults.
 107         $typeconfig = (array)$instance;
 108
 109         $typeconfig['sendname'] = $instance->instructorchoicesendname;
 110         $typeconfig['sendemailaddr'] = $instance->instructorchoicesendemailaddr;
 111         $typeconfig['customparameters'] = $instance->instructorcustomparameters;
 112         $typeconfig['acceptgrades'] = $instance->instructorchoiceacceptgrades;
 113         $typeconfig['allowroster'] = $instance->instructorchoiceallowroster;
 114         $typeconfig['forcessl'] = '0';
 115     }
 116
 117     // Default the organizationid if not specified.
 118     if (empty($typeconfig['organizationid'])) {
 119         $urlparts = parse_url($CFG->wwwroot);
 120
 121         $typeconfig['organizationid'] = $urlparts['host'];
 122     }
 123
 124     if (isset($tool->toolproxyid)) {
 125         $toolproxy = lti_get_tool_proxy($tool->toolproxyid);
 126         $key = $toolproxy->guid;
 127         $secret = $toolproxy->secret;
 128     } else {
 129         $toolproxy = null;
 130         if (!empty($instance->resourcekey)) {
 131             $key = $instance->resourcekey;
 132         } else if (!empty($typeconfig['resourcekey'])) {
 133             $key = $typeconfig['resourcekey'];
 134         } else {
 135             $key = '';
 136         }
 137         if (!empty($instance->password)) {
 138             $secret = $instance->password;
 139         } else if (!empty($typeconfig['password'])) {
 140             $secret = $typeconfig['password'];
 141         } else {
 142             $secret = '';
 143         }
 144     }
 145
 146     $endpoint = !empty($instance->toolurl) ? $instance->toolurl : $typeconfig['toolurl'];
 147     $endpoint = trim($endpoint);
 148
 149     // If the current request is using SSL and a secure tool URL is specified, use it.
 150     if (lti_request_is_using_ssl() && !empty($instance->securetoolurl)) {
 151         $endpoint = trim($instance->securetoolurl);
 152     }
 153
 154     // If SSL is forced, use the secure tool url if specified. Otherwise, make sure https is on the normal launch URL.
 155     if (isset($typeconfig['forcessl']) && ($typeconfig['forcessl'] == '1')) {
 156         if (!empty($instance->securetoolurl)) {
 157             $endpoint = trim($instance->securetoolurl);
 158         }
 159
 160         $endpoint = lti_ensure_url_is_https($endpoint);
 161     } else {
 162         if (!strstr($endpoint, '://')) {
 163             $endpoint = 'http://' . $endpoint;
 164         }
 165     }
 166
 167     $orgid = $typeconfig['organizationid'];
 168
 169     $course = $PAGE->course;
 170     $islti2 = isset($tool->toolproxyid);
 171     $allparams = lti_build_request($instance, $typeconfig, $course, $typeid, $islti2);
 172     if ($islti2) {
 173         $requestparams = lti_build_request_lti2($tool, $allparams);
 174     } else {
 175         $requestparams = $allparams;
 176     }
 177     $requestparams = array_merge($requestparams, lti_build_standard_request($instance, $orgid, $islti2));
 178     $customstr = '';
 179     if (isset($typeconfig['customparameters'])) {
 180         $customstr = $typeconfig['customparameters'];
 181     }
 182     $requestparams = array_merge($requestparams, lti_build_custom_parameters($toolproxy, $tool, $instance, $allparams, $customstr,
 183         $instance->instructorcustomparameters, $islti2));
 184
 185     $launchcontainer = lti_get_launch_container($instance, $typeconfig);
 186     $returnurlparams = array('course' => $course->id,
 187                              'launch_container' => $launchcontainer,
 188                              'instanceid' => $instance->id,
 189                              'sesskey' => sesskey());
 190
 191     // Add the return URL. We send the launch container along to help us avoid frames-within-frames when the user returns.
 192     $url = new \moodle_url('/mod/lti/return.php', $returnurlparams);
 193     $returnurl = $url->out(false);
 194
 195     if (isset($typeconfig['forcessl']) && ($typeconfig['forcessl'] == '1')) {
 196         $returnurl = lti_ensure_url_is_https($returnurl);
 197     }
 198
 199     $target = '';
 200     switch($launchcontainer) {
 201         case LTI_LAUNCH_CONTAINER_EMBED:
 202         case LTI_LAUNCH_CONTAINER_EMBED_NO_BLOCKS:
 203             $target = 'iframe';
 204             break;
 205         case LTI_LAUNCH_CONTAINER_REPLACE_MOODLE_WINDOW:
 206             $target = 'frame';
 207             break;
 208         case LTI_LAUNCH_CONTAINER_WINDOW:
 209             $target = 'window';
 210             break;
 211     }
 212     if (!empty($target)) {
 213         $requestparams['launch_presentation_document_target'] = $target;
 214     }
 215
 216     $requestparams['launch_presentation_return_url'] = $returnurl;
 217
 218     // Allow request params to be updated by sub-plugins.
 219     $plugins = core_component::get_plugin_list('ltisource');
 220     foreach (array_keys($plugins) as $plugin) {
 221         $pluginparams = component_callback('ltisource_'.$plugin, 'before_launch',
 222             array($instance, $endpoint, $requestparams), array());
 223
 224         if (!empty($pluginparams) && is_array($pluginparams)) {
 225             $requestparams = array_merge($requestparams, $pluginparams);
 226         }
 227     }
 228
 229     if (!empty($key) && !empty($secret)) {
 230         $parms = lti_sign_parameters($requestparams, $endpoint, "POST", $key, $secret);
 231
 232         $endpointurl = new \moodle_url($endpoint);
 233         $endpointparams = $endpointurl->params();
 234
 235         // Strip querystring params in endpoint url from $parms to avoid duplication.
 236         if (!empty($endpointparams) && !empty($parms)) {
 237             foreach (array_keys($endpointparams) as $paramname) {
 238                 if (isset($parms[$paramname])) {
 239                     unset($parms[$paramname]);
 240                 }
 241             }
 242         }
 243
 244     } else {
 245         // If no key and secret, do the launch unsigned.
 246         $returnurlparams['unsigned'] = '1';
 247         $parms = $requestparams;
 248     }
 249
 250     return array($endpoint, $parms);
 251 }
 252
 253 /**
 254  * Launch an external tool activity.
 255  *
 256  * @param  stdClass $instance the external tool activity settings
 257  * @return string The HTML code containing the javascript code for the launch
 258  */
 259 function lti_launch_tool($instance) {
 260
 261     list($endpoint, $parms) = lti_get_launch_data($instance);
 262     $debuglaunch = ( $instance->debuglaunch == 1 );
 263
 264     $content = lti_post_launch_html($parms, $endpoint, $debuglaunch);
 265
 266     echo $content;
 267 }
 268
 269 /**
 270  * Prepares an LTI registration request message
 271  *
 272  * $param object $instance       Tool Proxy instance object
 273  */
 274 function lti_register($toolproxy) {
 275     global $PAGE, $CFG;
 276
 277     $key = $toolproxy->guid;
 278     $secret = $toolproxy->secret;
 279     $endpoint = $toolproxy->regurl;
 280
 281     $requestparams = array();
 282     $requestparams['lti_message_type'] = 'ToolProxyRegistrationRequest';
 283     $requestparams['lti_version'] = 'LTI-2p0';
 284     $requestparams['reg_key'] = $key;
 285     $requestparams['reg_password'] = $secret;
 286
 287     // Change the status to pending.
 288     $toolproxy->state = LTI_TOOL_PROXY_STATE_PENDING;
 289     lti_update_tool_proxy($toolproxy);
 290
 291     // Add the profile URL.
 292     $profileservice = lti_get_service_by_name('profile');
 293     $profileservice->set_tool_proxy($toolproxy);
 294     $requestparams['tc_profile_url'] = $profileservice->parse_value('$ToolConsumerProfile.url');
 295
 296     // Add the return URL.
 297     $returnurlparams = array('id' => $toolproxy->id, 'sesskey' => sesskey());
 298     $url = new \moodle_url('/mod/lti/registrationreturn.php', $returnurlparams);
 299     $returnurl = $url->out(false);
 300
 301     $requestparams['launch_presentation_return_url'] = $returnurl;
 302     $content = lti_post_launch_html($requestparams, $endpoint, false);
 303
 304     echo $content;
 305 }
 306
 307 /**
 308  * Build source ID
 309  *
 310  * @param int $instanceid
 311  * @param int $userid
 312  * @param string $servicesalt
 313  * @param null|int $typeid
 314  * @param null|int $launchid
 315  * @return stdClass
 316  */
 317 function lti_build_sourcedid($instanceid, $userid, $servicesalt, $typeid = null, $launchid = null) {
 318     $data = new \stdClass();
 319
 320     $data->instanceid = $instanceid;
 321     $data->userid = $userid;
 322     $data->typeid = $typeid;
 323     if (!empty($launchid)) {
 324         $data->launchid = $launchid;
 325     } else {
 326         $data->launchid = mt_rand();
 327     }
 328
 329     $json = json_encode($data);
 330
 331     $hash = hash('sha256', $json . $servicesalt, false);
 332
 333     $container = new \stdClass();
 334     $container->data = $data;
 335     $container->hash = $hash;
 336
 337     return $container;
 338 }
 339
 340 /**
 341  * This function builds the request that must be sent to the tool producer
 342  *
 343  * @param object    $instance       Basic LTI instance object
 344  * @param array     $typeconfig     Basic LTI tool configuration
 345  * @param object    $course         Course object
 346  * @param int|null  $typeid         Basic LTI tool ID
 347  * @param boolean   $islti2         True if an LTI 2 tool is being launched
 348  *
 349  * @return array                    Request details
 350  */
 351 function lti_build_request($instance, $typeconfig, $course, $typeid = null, $islti2 = false) {
 352     global $USER, $CFG;
 353
 354     if (empty($instance->cmid)) {
 355         $instance->cmid = 0;
 356     }
 357
 358     $role = lti_get_ims_role($USER, $instance->cmid, $instance->course, $islti2);
 359
 360     $intro = '';
 361     if (!empty($instance->cmid)) {
 362         $intro = format_module_intro('lti', $instance, $instance->cmid);
 363         $intro = html_to_text($intro, 0, false);
 364
 365         // This may look weird, but this is required for new lines
 366         // so we generate the same OAuth signature as the tool provider.
 367         $intro = str_replace("\n", "\r\n", $intro);
 368     }
 369     $requestparams = array(
 370         'resource_link_title' => $instance->name,
 371         'resource_link_description' => $intro,
 372         'user_id' => $USER->id,
 373         'lis_person_sourcedid' => $USER->idnumber,
 374         'roles' => $role,
 375         'context_id' => $course->id,
 376         'context_label' => $course->shortname,
 377         'context_title' => $course->fullname,
 378     );
 379     if (!empty($instance->id)) {
 380         $requestparams['resource_link_id'] = $instance->id;
 381     }
 382     if (!empty($instance->resource_link_id)) {
 383         $requestparams['resource_link_id'] = $instance->resource_link_id;
 384     }
 385     if ($course->format == 'site') {
 386         $requestparams['context_type'] = 'Group';
 387     } else {
 388         $requestparams['context_type'] = 'CourseSection';
 389         $requestparams['lis_course_section_sourcedid'] = $course->idnumber;
 390     }
 391     $placementsecret = $instance->servicesalt;
 392
 393     if ( !empty($instance->id) && isset($placementsecret) && ($islti2 ||
 394          $typeconfig['acceptgrades'] == LTI_SETTING_ALWAYS ||
 395          ($typeconfig['acceptgrades'] == LTI_SETTING_DELEGATE && $instance->instructorchoiceacceptgrades == LTI_SETTING_ALWAYS))) {
 396
 397         $sourcedid = json_encode(lti_build_sourcedid($instance->id, $USER->id, $placementsecret, $typeid));
 398         $requestparams['lis_result_sourcedid'] = $sourcedid;
 399
 400         // Add outcome service URL.
 401         $serviceurl = new \moodle_url('/mod/lti/service.php');
 402         $serviceurl = $serviceurl->out();
 403
 404         $forcessl = false;
 405         if (!empty($CFG->mod_lti_forcessl)) {
 406             $forcessl = true;
 407         }
 408
 409         if ((isset($typeconfig['forcessl']) && ($typeconfig['forcessl'] == '1')) or $forcessl) {
 410             $serviceurl = lti_ensure_url_is_https($serviceurl);
 411         }
 412
 413         $requestparams['lis_outcome_service_url'] = $serviceurl;
 414     }
 415
 416     // Send user's name and email data if appropriate.
 417     if ($islti2 || $typeconfig['sendname'] == LTI_SETTING_ALWAYS ||
 418          ( $typeconfig['sendname'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendname == LTI_SETTING_ALWAYS ) ) {
 419         $requestparams['lis_person_name_given'] = $USER->firstname;
 420         $requestparams['lis_person_name_family'] = $USER->lastname;
 421         $requestparams['lis_person_name_full'] = $USER->firstname . ' ' . $USER->lastname;
 422         $requestparams['ext_user_username'] = $USER->username;
 423     }
 424
 425     if ($islti2 || $typeconfig['sendemailaddr'] == LTI_SETTING_ALWAYS ||
 426          ($typeconfig['sendemailaddr'] == LTI_SETTING_DELEGATE && $instance->instructorchoicesendemailaddr == LTI_SETTING_ALWAYS)) {
 427         $requestparams['lis_person_contact_email_primary'] = $USER->email;
 428     }
 429
 430     return $requestparams;
 431 }
 432
 433 /**
 434  * This function builds the request that must be sent to an LTI 2 tool provider
 435  *
 436  * @param object    $tool           Basic LTI tool object
 437  * @param array     $params         Custom launch parameters
 438  *
 439  * @return array                    Request details
 440  */
 441 function lti_build_request_lti2($tool, $params) {
 442
 443     $requestparams = array();
 444
 445     $capabilities = lti_get_capabilities();
 446     $enabledcapabilities = explode("\n", $tool->enabledcapability);
 447     foreach ($enabledcapabilities as $capability) {
 448         if (array_key_exists($capability, $capabilities)) {
 449             $val = $capabilities[$capability];
 450             if ($val && (substr($val, 0, 1) != '$')) {
 451                 if (isset($params[$val])) {
 452                     $requestparams[$capabilities[$capability]] = $params[$capabilities[$capability]];
 453                 }
 454             }
 455         }
 456     }
 457
 458     return $requestparams;
 459
 460 }
 461
 462 /**
 463  * This function builds the standard parameters for an LTI 1 or 2 request that must be sent to the tool producer
 464  *
 465  * @param object    $instance       Basic LTI instance object
 466  * @param string    $orgid          Organisation ID
 467  * @param boolean   $islti2         True if an LTI 2 tool is being launched
 468  *
 469  * @return array                    Request details
 470  */
 471 function lti_build_standard_request($instance, $orgid, $islti2) {
 472     global $CFG;
 473
 474     $requestparams = array();
 475
 476     $requestparams['resource_link_id'] = $instance->id;
 477     if (property_exists($instance, 'resource_link_id') and !empty($instance->resource_link_id)) {
 478         $requestparams['resource_link_id'] = $instance->resource_link_id;
 479     }
 480
 481     $requestparams['launch_presentation_locale'] = current_language();
 482
 483     // Make sure we let the tool know what LMS they are being called from.
 484     $requestparams['ext_lms'] = 'moodle-2';
 485     $requestparams['tool_consumer_info_product_family_code'] = 'moodle';
 486     $requestparams['tool_consumer_info_version'] = strval($CFG->version);
 487
 488     // Add oauth_callback to be compliant with the 1.0A spec.
 489     $requestparams['oauth_callback'] = 'about:blank';
 490
 491     if (!$islti2) {
 492         $requestparams['lti_version'] = 'LTI-1p0';
 493     } else {
 494         $requestparams['lti_version'] = 'LTI-2p0';
 495     }
 496     $requestparams['lti_message_type'] = 'basic-lti-launch-request';
 497
 498     if ($orgid) {
 499         $requestparams["tool_consumer_instance_guid"] = $orgid;
 500     }
 501     if (!empty($CFG->mod_lti_institution_name)) {
 502         $requestparams['tool_consumer_instance_name'] = $CFG->mod_lti_institution_name;
 503     } else {
 504         $requestparams['tool_consumer_instance_name'] = get_site()->fullname;
 505     }
 506
 507     return $requestparams;
 508 }
 509
 510 /**
 511  * This function builds the custom parameters
 512  *
 513  * @param object    $toolproxy      Tool proxy instance object
 514  * @param object    $tool           Tool instance object
 515  * @param object    $instance       Tool placement instance object
 516  * @param array     $params         LTI launch parameters
 517  * @param string    $customstr      Custom parameters defined for tool
 518  * @param string    $instructorcustomstr      Custom parameters defined for this placement
 519  * @param boolean   $islti2         True if an LTI 2 tool is being launched
 520  *
 521  * @return array                    Custom parameters
 522  */
 523 function lti_build_custom_parameters($toolproxy, $tool, $instance, $params, $customstr, $instructorcustomstr, $islti2) {
 524
 525     // Concatenate the custom parameters from the administrator and the instructor
 526     // Instructor parameters are only taken into consideration if the administrator
 527     // has given permission.
 528     $custom = array();
 529     if ($customstr) {
 530         $custom = lti_split_custom_parameters($toolproxy, $tool, $params, $customstr, $islti2);
 531     }
 532     if (!isset($typeconfig['allowinstructorcustom']) || $typeconfig['allowinstructorcustom'] != LTI_SETTING_NEVER) {
 533         if ($instructorcustomstr) {
 534             $custom = array_merge(lti_split_custom_parameters($toolproxy, $tool, $params,
 535                 $instructorcustomstr, $islti2), $custom);
 536         }
 537     }
 538     if ($islti2) {
 539         $custom = array_merge(lti_split_custom_parameters($toolproxy, $tool, $params,
 540             $tool->parameter, true), $custom);
 541         $settings = lti_get_tool_settings($tool->toolproxyid);
 542         $custom = array_merge($custom, lti_get_custom_parameters($toolproxy, $tool, $params, $settings));
 543         $settings = lti_get_tool_settings($tool->toolproxyid, $instance->course);
 544         $custom = array_merge($custom, lti_get_custom_parameters($toolproxy, $tool, $params, $settings));
 545         $settings = lti_get_tool_settings($tool->toolproxyid, $instance->course, $instance->id);
 546         $custom = array_merge($custom, lti_get_custom_parameters($toolproxy, $tool, $params, $settings));
 547     }
 548
 549     return $custom;
 550 }
 551
 552 function lti_get_tool_table($tools, $id) {
 553     global $CFG, $OUTPUT, $USER;
 554     $html = '';
 555
 556     $typename = get_string('typename', 'lti');
 557     $baseurl = get_string('baseurl', 'lti');
 558     $action = get_string('action', 'lti');
 559     $createdon = get_string('createdon', 'lti');
 560
 561     if (!empty($tools)) {
 562         $html .= "
 563         <div id=\"{$id}_tools_container\" style=\"margin-top:.5em;margin-bottom:.5em\">
 564             <table id=\"{$id}_tools\">
 565                 <thead>
 566                     <tr>
 567                         <th>$typename</th>
 568                         <th>$baseurl</th>
 569                         <th>$createdon</th>
 570                         <th>$action</th>
 571                     </tr>
 572                 </thead>
 573         ";
 574
 575         foreach ($tools as $type) {
 576             $date = userdate($type->timecreated, get_string('strftimedatefullshort', 'core_langconfig'));
 577             $accept = get_string('accept', 'lti');
 578             $update = get_string('update', 'lti');
 579             $delete = get_string('delete', 'lti');
 580
 581             if (empty($type->toolproxyid)) {
 582                 $baseurl = new \moodle_url('/mod/lti/typessettings.php', array(
 583                         'action' => 'accept',
 584                         'id' => $type->id,
 585                         'sesskey' => sesskey(),
 586                         'tab' => $id
 587                     ));
 588                 $ref = $type->baseurl;
 589             } else {
 590                 $baseurl = new \moodle_url('/mod/lti/toolssettings.php', array(
 591                         'action' => 'accept',
 592                         'id' => $type->id,
 593                         'sesskey' => sesskey(),
 594                         'tab' => $id
 595                     ));
 596                 $ref = $type->tpname;
 597             }
 598
 599             $accepthtml = $OUTPUT->action_icon($baseurl,
 600                     new \pix_icon('t/check', $accept, '', array('class' => 'iconsmall')), null,
 601                     array('title' => $accept, 'class' => 'editing_accept'));
 602
 603             $deleteaction = 'delete';
 604
 605             if ($type->state == LTI_TOOL_STATE_CONFIGURED) {
 606                 $accepthtml = '';
 607             }
 608
 609             if ($type->state != LTI_TOOL_STATE_REJECTED) {
 610                 $deleteaction = 'reject';
 611                 $delete = get_string('reject', 'lti');
 612             }
 613
 614             $updateurl = clone($baseurl);
 615             $updateurl->param('action', 'update');
 616             $updatehtml = $OUTPUT->action_icon($updateurl,
 617                     new \pix_icon('t/edit', $update, '', array('class' => 'iconsmall')), null,
 618                     array('title' => $update, 'class' => 'editing_update'));
 619
 620             if (($type->state != LTI_TOOL_STATE_REJECTED) || empty($type->toolproxyid)) {
 621                 $deleteurl = clone($baseurl);
 622                 $deleteurl->param('action', $deleteaction);
 623                 $deletehtml = $OUTPUT->action_icon($deleteurl,
 624                         new \pix_icon('t/delete', $delete, '', array('class' => 'iconsmall')), null,
 625                         array('title' => $delete, 'class' => 'editing_delete'));
 626             } else {
 627                 $deletehtml = '';
 628             }
 629             $html .= "
 630             <tr>
 631                 <td>
 632                     {$type->name}
 633                 </td>
 634                 <td>
 635                     {$ref}
 636                 </td>
 637                 <td>
 638                     {$date}
 639                 </td>
 640                 <td align=\"center\">
 641                     {$accepthtml}{$updatehtml}{$deletehtml}
 642                 </td>
 643             </tr>
 644             ";
 645         }
 646         $html .= '</table></div>';
 647     } else {
 648         $html .= get_string('no_' . $id, 'lti');
 649     }
 650
 651     return $html;
 652 }
 653
 654 /**
 655  * This function builds the tab for a category of tool proxies
 656  *
 657  * @param object    $toolproxies    Tool proxy instance objects
 658  * @param string    $id             Category ID
 659  *
 660  * @return string                   HTML for tab
 661  */
 662 function lti_get_tool_proxy_table($toolproxies, $id) {
 663     global $OUTPUT;
 664
 665     if (!empty($toolproxies)) {
 666         $typename = get_string('typename', 'lti');
 667         $url = get_string('registrationurl', 'lti');
 668         $action = get_string('action', 'lti');
 669         $createdon = get_string('createdon', 'lti');
 670
 671         $html = <<< EOD
 672         <div id="{$id}_tool_proxies_container" style="margin-top: 0.5em; margin-bottom: 0.5em">
 673             <table id="{$id}_tool_proxies">
 674                 <thead>
 675                     <tr>
 676                         <th>{$typename}</th>
 677                         <th>{$url}</th>
 678                         <th>{$createdon}</th>
 679                         <th>{$action}</th>
 680                     </tr>
 681                 </thead>
 682 EOD;
 683         foreach ($toolproxies as $toolproxy) {
 684             $date = userdate($toolproxy->timecreated, get_string('strftimedatefullshort', 'core_langconfig'));
 685             $accept = get_string('register', 'lti');
 686             $update = get_string('update', 'lti');
 687             $delete = get_string('delete', 'lti');
 688
 689             $baseurl = new \moodle_url('/mod/lti/registersettings.php', array(
 690                     'action' => 'accept',
 691                     'id' => $toolproxy->id,
 692                     'sesskey' => sesskey(),
 693                     'tab' => $id
 694                 ));
 695
 696             $registerurl = new \moodle_url('/mod/lti/register.php', array(
 697                     'id' => $toolproxy->id,
 698                     'sesskey' => sesskey(),
 699                     'tab' => 'tool_proxy'
 700                 ));
 701
 702             $accepthtml = $OUTPUT->action_icon($registerurl,
 703                     new \pix_icon('t/check', $accept, '', array('class' => 'iconsmall')), null,
 704                     array('title' => $accept, 'class' => 'editing_accept'));
 705
 706             $deleteaction = 'delete';
 707
 708             if ($toolproxy->state != LTI_TOOL_PROXY_STATE_CONFIGURED) {
 709                 $accepthtml = '';
 710             }
 711
 712             if (($toolproxy->state == LTI_TOOL_PROXY_STATE_CONFIGURED) || ($toolproxy->state == LTI_TOOL_PROXY_STATE_PENDING)) {
 713                 $delete = get_string('cancel', 'lti');
 714             }
 715
 716             $updateurl = clone($baseurl);
 717             $updateurl->param('action', 'update');
 718             $updatehtml = $OUTPUT->action_icon($updateurl,
 719                     new \pix_icon('t/edit', $update, '', array('class' => 'iconsmall')), null,
 720                     array('title' => $update, 'class' => 'editing_update'));
 721
 722             $deleteurl = clone($baseurl);
 723             $deleteurl->param('action', $deleteaction);
 724             $deletehtml = $OUTPUT->action_icon($deleteurl,
 725                     new \pix_icon('t/delete', $delete, '', array('class' => 'iconsmall')), null,
 726                     array('title' => $delete, 'class' => 'editing_delete'));
 727             $html .= <<< EOD
 728             <tr>
 729                 <td>
 730                     {$toolproxy->name}
 731                 </td>
 732                 <td>
 733                     {$toolproxy->regurl}
 734                 </td>
 735                 <td>
 736                     {$date}
 737                 </td>
 738                 <td align="center">
 739                     {$accepthtml}{$updatehtml}{$deletehtml}
 740                 </td>
 741             </tr>
 742 EOD;
 743         }
 744         $html .= '</table></div>';
 745     } else {
 746         $html = get_string('no_' . $id, 'lti');
 747     }
 748
 749     return $html;
 750 }
 751
 752 /**
 753  * Extracts the enabled capabilities into an array, including those implicitly declared in a parameter
 754  *
 755  * @param object    $tool           Tool instance object
 756  *
 757  * @return Array of enabled capabilities
 758  */
 759 function lti_get_enabled_capabilities($tool) {
 760     if (!empty($tool->enabledcapability)) {
 761         $enabledcapabilities = explode("\n", $tool->enabledcapability);
 762     } else {
 763         $enabledcapabilities = array();
 764     }
 765     $paramstr = str_replace("\r\n", "\n", $tool->parameter);
 766     $paramstr = str_replace("\n\r", "\n", $paramstr);
 767     $paramstr = str_replace("\r", "\n", $paramstr);
 768     $params = explode("\n", $paramstr);
 769     foreach ($params as $param) {
 770         $pos = strpos($param, '=');
 771         if (($pos === false) || ($pos < 1)) {
 772             continue;
 773         }
 774         $value = trim(core_text::substr($param, $pos + 1, strlen($param)));
 775         if (substr($value, 0, 1) == '$') {
 776             $value = substr($value, 1);
 777             if (!in_array($value, $enabledcapabilities)) {
 778                 $enabledcapabilities[] = $value;
 779             }
 780         }
 781     }
 782     return $enabledcapabilities;
 783 }
 784
 785 /**
 786  * Splits the custom parameters field to the various parameters
 787  *
 788  * @param object    $toolproxy      Tool proxy instance object
 789  * @param object    $tool           Tool instance object
 790  * @param array     $params         LTI launch parameters
 791  * @param string    $customstr      String containing the parameters
 792  * @param boolean   $islti2         True if an LTI 2 tool is being launched
 793  *
 794  * @return Array of custom parameters
 795  */
 796 function lti_split_custom_parameters($toolproxy, $tool, $params, $customstr, $islti2 = false) {
 797     $customstr = str_replace("\r\n", "\n", $customstr);
 798     $customstr = str_replace("\n\r", "\n", $customstr);
 799     $customstr = str_replace("\r", "\n", $customstr);
 800     $lines = explode("\n", $customstr);  // Or should this split on "/[\n;]/"?
 801     $retval = array();
 802     foreach ($lines as $line) {
 803         $pos = strpos($line, '=');
 804         if ( $pos === false || $pos < 1 ) {
 805             continue;
 806         }
 807         $key = trim(core_text::substr($line, 0, $pos));
 808         $val = trim(core_text::substr($line, $pos + 1, strlen($line)));
 809         $val = lti_parse_custom_parameter($toolproxy, $tool, $params, $val, $islti2);
 810         $key2 = lti_map_keyname($key);
 811         $retval['custom_'.$key2] = $val;
 812         if ($islti2 && ($key != $key2)) {
 813             $retval['custom_'.$key] = $val;
 814         }
 815     }
 816     return $retval;
 817 }
 818
 819 /**
 820  * Adds the custom parameters to an array
 821  *
 822  * @param object    $toolproxy      Tool proxy instance object
 823  * @param object    $tool           Tool instance object
 824  * @param array     $params         LTI launch parameters
 825  * @param array     $parameters     Array containing the parameters
 826  *
 827  * @return array    Array of custom parameters
 828  */
 829 function lti_get_custom_parameters($toolproxy, $tool, $params, $parameters) {
 830     $retval = array();
 831     foreach ($parameters as $key => $val) {
 832         $key2 = lti_map_keyname($key);
 833         $val = lti_parse_custom_parameter($toolproxy, $tool, $params, $val, true);
 834         $retval['custom_'.$key2] = $val;
 835         if ($key != $key2) {
 836             $retval['custom_'.$key] = $val;
 837         }
 838     }
 839     return $retval;
 840 }
 841
 842 /**
 843  * Parse a custom parameter to replace any substitution variables
 844  *
 845  * @param object    $toolproxy      Tool proxy instance object
 846  * @param object    $tool           Tool instance object
 847  * @param array     $params         LTI launch parameters
 848  * @param string    $value          Custom parameter value
 849  * @param boolean   $islti2         True if an LTI 2 tool is being launched
 850  *
 851  * @return Parsed value of custom parameter
 852  */
 853 function lti_parse_custom_parameter($toolproxy, $tool, $params, $value, $islti2) {
 854     global $USER, $COURSE;
 855
 856     if ($value) {
 857         if (substr($value, 0, 1) == '\\') {
 858             $value = substr($value, 1);
 859         } else if (substr($value, 0, 1) == '$') {
 860             $value1 = substr($value, 1);
 861             $enabledcapabilities = lti_get_enabled_capabilities($tool);
 862             if (!$islti2 || in_array($value1, $enabledcapabilities)) {
 863                 $capabilities = lti_get_capabilities();
 864                 if (array_key_exists($value1, $capabilities)) {
 865                     $val = $capabilities[$value1];
 866                     if ($val) {
 867                         if (substr($val, 0, 1) != '$') {
 868                             $value = $params[$val];
 869                         } else {
 870                             $valarr = explode('->', substr($val, 1), 2);
 871                             $value = "{${$valarr[0]}->{$valarr[1]}}";
 872                             $value = str_replace('<br />' , ' ', $value);
 873                             $value = str_replace('<br>' , ' ', $value);
 874                             $value = format_string($value);
 875                         }
 876                     }
 877                 } else if ($islti2) {
 878                     $val = $value;
 879                     $services = lti_get_services();
 880                     foreach ($services as $service) {
 881                         $service->set_tool_proxy($toolproxy);
 882                         $value = $service->parse_value($val);
 883                         if ($val != $value) {
 884                             break;
 885                         }
 886                     }
 887                 }
 888             }
 889         }
 890     }
 891     return $value;
 892 }
 893
 894 /**
 895  * Used for building the names of the different custom parameters
 896  *
 897  * @param string $key   Parameter name
 898  *
 899  * @return string       Processed name
 900  */
 901 function lti_map_keyname($key) {
 902     $newkey = "";
 903     $key = core_text::strtolower(trim($key));
 904     foreach (str_split($key) as $ch) {
 905         if ( ($ch >= 'a' && $ch <= 'z') || ($ch >= '0' && $ch <= '9') ) {
 906             $newkey .= $ch;
 907         } else {
 908             $newkey .= '_';
 909         }
 910     }
 911     return $newkey;
 912 }
 913
 914 /**
 915  * Gets the IMS role string for the specified user and LTI course module.
 916  *
 917  * @param mixed    $user      User object or user id
 918  * @param int      $cmid      The course module id of the LTI activity
 919  * @param int      $courseid  The course id of the LTI activity
 920  * @param boolean  $islti2    True if an LTI 2 tool is being launched
 921  *
 922  * @return string A role string suitable for passing with an LTI launch
 923  */
 924 function lti_get_ims_role($user, $cmid, $courseid, $islti2) {
 925     $roles = array();
 926
 927     if (empty($cmid)) {
 928         // If no cmid is passed, check if the user is a teacher in the course
 929         // This allows other modules to programmatically "fake" a launch without
 930         // a real LTI instance.
 931         $coursecontext = context_course::instance($courseid);
 932
 933         if (has_capability('moodle/course:manageactivities', $coursecontext, $user)) {
 934             array_push($roles, 'Instructor');
 935         } else {
 936             array_push($roles, 'Learner');
 937         }
 938     } else {
 939         $context = context_module::instance($cmid);
 940
 941         if (has_capability('mod/lti:manage', $context)) {
 942             array_push($roles, 'Instructor');
 943         } else {
 944             array_push($roles, 'Learner');
 945         }
 946     }
 947
 948     if (is_siteadmin($user)) {
 949         if (!$islti2) {
 950             array_push($roles, 'urn:lti:sysrole:ims/lis/Administrator', 'urn:lti:instrole:ims/lis/Administrator');
 951         } else {
 952             array_push($roles, 'http://purl.imsglobal.org/vocab/lis/v2/person#Administrator');
 953         }
 954     }
 955
 956     return join(',', $roles);
 957 }
 958
 959 /**
 960  * Returns configuration details for the tool
 961  *
 962  * @param int $typeid   Basic LTI tool typeid
 963  *
 964  * @return array        Tool Configuration
 965  */
 966 function lti_get_type_config($typeid) {
 967     global $DB;
 968
 969     $query = "SELECT name, value
 970                 FROM {lti_types_config}
 971                WHERE typeid = :typeid1
 972            UNION ALL
 973               SELECT 'toolurl' AS name, " . $DB->sql_compare_text('baseurl', 1333) . " AS value
 974                 FROM {lti_types}
 975                WHERE id = :typeid2
 976            UNION ALL
 977               SELECT 'icon' AS name, " . $DB->sql_compare_text('icon', 1333) . " AS value
 978                 FROM {lti_types}
 979                WHERE id = :typeid3
 980            UNION ALL
 981               SELECT 'secureicon' AS name, " . $DB->sql_compare_text('secureicon', 1333) . " AS value
 982                 FROM {lti_types}
 983                WHERE id = :typeid4";
 984
 985     $typeconfig = array();
 986     $configs = $DB->get_records_sql($query,
 987         array('typeid1' => $typeid, 'typeid2' => $typeid, 'typeid3' => $typeid, 'typeid4' => $typeid));
 988
 989     if (!empty($configs)) {
 990         foreach ($configs as $config) {
 991             $typeconfig[$config->name] = $config->value;
 992         }
 993     }
 994
 995     return $typeconfig;
 996 }
 997
 998 function lti_get_tools_by_url($url, $state, $courseid = null) {
 999     $domain = lti_get_domain_from_url($url);
1000
1001     return lti_get_tools_by_domain($domain, $state, $courseid);
1002 }
1003
1004 function lti_get_tools_by_domain($domain, $state = null, $courseid = null) {
1005     global $DB, $SITE;
1006
1007     $filters = array('tooldomain' => $domain);
1008
1009     $statefilter = '';
1010     $coursefilter = '';
1011
1012     if ($state) {
1013         $statefilter = 'AND state = :state';
1014     }
1015
1016     if ($courseid && $courseid != $SITE->id) {
1017         $coursefilter = 'OR course = :courseid';
1018     }
1019
1020     $query = "SELECT *
1021                 FROM {lti_types}
1022                WHERE tooldomain = :tooldomain
1023                  AND (course = :siteid $coursefilter)
1024                  $statefilter";
1025
1026     return $DB->get_records_sql($query, array(
1027         'courseid' => $courseid,
1028         'siteid' => $SITE->id,
1029         'tooldomain' => $domain,
1030         'state' => $state
1031     ));
1032 }
1033
1034 /**
1035  * Returns all basicLTI tools configured by the administrator
1036  *
1037  */
1038 function lti_filter_get_types($course) {
1039     global $DB;
1040
1041     if (!empty($course)) {
1042         $where = "WHERE t.course = :course";
1043         $params = array('course' => $course);
1044     } else {
1045         $where = '';
1046         $params = array();
1047     }
1048     $query = "SELECT t.id, t.name, t.baseurl, t.state, t.toolproxyid, t.timecreated, tp.name tpname
1049                 FROM {lti_types} t LEFT OUTER JOIN {lti_tool_proxies} tp ON t.toolproxyid = tp.id
1050                 {$where}";
1051     return $DB->get_records_sql($query, $params);
1052 }
1053
1054 /**
1055  * Given an array of tools, filter them based on their state
1056  *
1057  * @param array $tools An array of lti_types records
1058  * @param int $state One of the LTI_TOOL_STATE_* constants
1059  * @return array
1060  */
1061 function lti_filter_tool_types(array $tools, $state) {
1062     $return = array();
1063     foreach ($tools as $key => $tool) {
1064         if ($tool->state == $state) {
1065             $return[$key] = $tool;
1066         }
1067     }
1068     return $return;
1069 }
1070
1071 function lti_get_types_for_add_instance() {
1072     global $DB, $SITE, $COURSE;
1073
1074     $query = "SELECT *
1075                 FROM {lti_types}
1076                WHERE coursevisible = 1
1077                  AND (course = :siteid OR course = :courseid)
1078                  AND state = :active";
1079
1080     $admintypes = $DB->get_records_sql($query,
1081         array('siteid' => $SITE->id, 'courseid' => $COURSE->id, 'active' => LTI_TOOL_STATE_CONFIGURED));
1082
1083     $types = array();
1084     $types[0] = (object)array('name' => get_string('automatic', 'lti'), 'course' => 0, 'toolproxyid' => null);
1085
1086     foreach ($admintypes as $type) {
1087         $types[$type->id] = $type;
1088     }
1089
1090     return $types;
1091 }
1092
1093 function lti_get_domain_from_url($url) {
1094     $matches = array();
1095
1096     if (preg_match(LTI_URL_DOMAIN_REGEX, $url, $matches)) {
1097         return $matches[1];
1098     }
1099 }
1100
1101 function lti_get_tool_by_url_match($url, $courseid = null, $state = LTI_TOOL_STATE_CONFIGURED) {
1102     $possibletools = lti_get_tools_by_url($url, $state, $courseid);
1103
1104     return lti_get_best_tool_by_url($url, $possibletools, $courseid);
1105 }
1106
1107 function lti_get_url_thumbprint($url) {
1108     // Parse URL requires a schema otherwise everything goes into 'path'.  Fixed 5.4.7 or later.
1109     if (preg_match('/https?:\/\//', $url) !== 1) {
1110         $url = 'http://'.$url;
1111     }
1112     $urlparts = parse_url(strtolower($url));
1113     if (!isset($urlparts['path'])) {
1114         $urlparts['path'] = '';
1115     }
1116
1117     if (!isset($urlparts['host'])) {
1118         $urlparts['host'] = '';
1119     }
1120
1121     if (substr($urlparts['host'], 0, 4) === 'www.') {
1122         $urlparts['host'] = substr($urlparts['host'], 4);
1123     }
1124
1125     return $urllower = $urlparts['host'] . '/' . $urlparts['path'];
1126 }
1127
1128 function lti_get_best_tool_by_url($url, $tools, $courseid = null) {
1129     if (count($tools) === 0) {
1130         return null;
1131     }
1132
1133     $urllower = lti_get_url_thumbprint($url);
1134
1135     foreach ($tools as $tool) {
1136         $tool->_matchscore = 0;
1137
1138         $toolbaseurllower = lti_get_url_thumbprint($tool->baseurl);
1139
1140         if ($urllower === $toolbaseurllower) {
1141             // 100 points for exact thumbprint match.
1142             $tool->_matchscore += 100;
1143         } else if (substr($urllower, 0, strlen($toolbaseurllower)) === $toolbaseurllower) {
1144             // 50 points if tool thumbprint starts with the base URL thumbprint.
1145             $tool->_matchscore += 50;
1146         }
1147
1148         // Prefer course tools over site tools.
1149         if (!empty($courseid)) {
1150             // Minus 10 points for not matching the course id (global tools).
1151             if ($tool->course != $courseid) {
1152                 $tool->_matchscore -= 10;
1153             }
1154         }
1155     }
1156
1157     $bestmatch = array_reduce($tools, function($value, $tool) {
1158         if ($tool->_matchscore > $value->_matchscore) {
1159             return $tool;
1160         } else {
1161             return $value;
1162         }
1163
1164     }, (object)array('_matchscore' => -1));
1165
1166     // None of the tools are suitable for this URL.
1167     if ($bestmatch->_matchscore <= 0) {
1168         return null;
1169     }
1170
1171     return $bestmatch;
1172 }
1173
1174 function lti_get_shared_secrets_by_key($key) {
1175     global $DB;
1176
1177     // Look up the shared secret for the specified key in both the types_config table (for configured tools)
1178     // And in the lti resource table for ad-hoc tools.
1179     $query = "SELECT t2.value
1180                 FROM {lti_types_config} t1
1181                 JOIN {lti_types_config} t2 ON t1.typeid = t2.typeid
1182                 JOIN {lti_types} type ON t2.typeid = type.id
1183               WHERE t1.name = 'resourcekey'
1184                 AND t1.value = :key1
1185                 AND t2.name = 'password'
1186                 AND type.state = :configured1
1187                UNION
1188               SELECT tp.secret AS value
1189                 FROM {lti_tool_proxies} tp
1190                 JOIN {lti_types} t ON tp.id = t.toolproxyid
1191               WHERE tp.guid = :key2
1192                 AND t.state = :configured2
1193               UNION
1194              SELECT password AS value
1195                FROM {lti}
1196               WHERE resourcekey = :key3";
1197
1198     $sharedsecrets = $DB->get_records_sql($query, array('configured1' => LTI_TOOL_STATE_CONFIGURED,
1199         'configured2' => LTI_TOOL_STATE_CONFIGURED, 'key1' => $key, 'key2' => $key, 'key3' => $key));
1200
1201     $values = array_map(function($item) {
1202         return $item->value;
1203     }, $sharedsecrets);
1204
1205     // There should really only be one shared secret per key. But, we can't prevent
1206     // more than one getting entered. For instance, if the same key is used for two tool providers.
1207     return $values;
1208 }
1209
1210 /**
1211  * Delete a Basic LTI configuration
1212  *
1213  * @param int $id   Configuration id
1214  */
1215 function lti_delete_type($id) {
1216     global $DB;
1217
1218     // We should probably just copy the launch URL to the tool instances in this case... using a single query.
1219     /*
1220     $instances = $DB->get_records('lti', array('typeid' => $id));
1221     foreach ($instances as $instance) {
1222         $instance->typeid = 0;
1223         $DB->update_record('lti', $instance);
1224     }*/
1225
1226     $DB->delete_records('lti_types', array('id' => $id));
1227     $DB->delete_records('lti_types_config', array('typeid' => $id));
1228 }
1229
1230 function lti_set_state_for_type($id, $state) {
1231     global $DB;
1232
1233     $DB->update_record('lti_types', array('id' => $id, 'state' => $state));
1234 }
1235
1236 /**
1237  * Transforms a basic LTI object to an array
1238  *
1239  * @param object $ltiobject    Basic LTI object
1240  *
1241  * @return array Basic LTI configuration details
1242  */
1243 function lti_get_config($ltiobject) {
1244     $typeconfig = array();
1245     $typeconfig = (array)$ltiobject;
1246     $additionalconfig = lti_get_type_config($ltiobject->typeid);
1247     $typeconfig = array_merge($typeconfig, $additionalconfig);
1248     return $typeconfig;
1249 }
1250
1251 /**
1252  *
1253  * Generates some of the tool configuration based on the instance details
1254  *
1255  * @param int $id
1256  *
1257  * @return Instance configuration
1258  *
1259  */
1260 function lti_get_type_config_from_instance($id) {
1261     global $DB;
1262
1263     $instance = $DB->get_record('lti', array('id' => $id));
1264     $config = lti_get_config($instance);
1265
1266     $type = new \stdClass();
1267     $type->lti_fix = $id;
1268     if (isset($config['toolurl'])) {
1269         $type->lti_toolurl = $config['toolurl'];
1270     }
1271     if (isset($config['instructorchoicesendname'])) {
1272         $type->lti_sendname = $config['instructorchoicesendname'];
1273     }
1274     if (isset($config['instructorchoicesendemailaddr'])) {
1275         $type->lti_sendemailaddr = $config['instructorchoicesendemailaddr'];
1276     }
1277     if (isset($config['instructorchoiceacceptgrades'])) {
1278         $type->lti_acceptgrades = $config['instructorchoiceacceptgrades'];
1279     }
1280     if (isset($config['instructorchoiceallowroster'])) {
1281         $type->lti_allowroster = $config['instructorchoiceallowroster'];
1282     }
1283
1284     if (isset($config['instructorcustomparameters'])) {
1285         $type->lti_allowsetting = $config['instructorcustomparameters'];
1286     }
1287     return $type;
1288 }
1289
1290 /**
1291  * Generates some of the tool configuration based on the admin configuration details
1292  *
1293  * @param int $id
1294  *
1295  * @return Configuration details
1296  */
1297 function lti_get_type_type_config($id) {
1298     global $DB;
1299
1300     $basicltitype = $DB->get_record('lti_types', array('id' => $id));
1301     $config = lti_get_type_config($id);
1302
1303     $type = new \stdClass();
1304
1305     $type->lti_typename = $basicltitype->name;
1306
1307     $type->typeid = $basicltitype->id;
1308
1309     $type->toolproxyid = $basicltitype->toolproxyid;
1310
1311     $type->lti_toolurl = $basicltitype->baseurl;
1312
1313     $type->lti_parameters = $basicltitype->parameter;
1314
1315     $type->lti_icon = $basicltitype->icon;
1316
1317     $type->lti_secureicon = $basicltitype->secureicon;
1318
1319     if (isset($config['resourcekey'])) {
1320         $type->lti_resourcekey = $config['resourcekey'];
1321     }
1322     if (isset($config['password'])) {
1323         $type->lti_password = $config['password'];
1324     }
1325
1326     if (isset($config['sendname'])) {
1327         $type->lti_sendname = $config['sendname'];
1328     }
1329     if (isset($config['instructorchoicesendname'])) {
1330         $type->lti_instructorchoicesendname = $config['instructorchoicesendname'];
1331     }
1332     if (isset($config['sendemailaddr'])) {
1333         $type->lti_sendemailaddr = $config['sendemailaddr'];
1334     }
1335     if (isset($config['instructorchoicesendemailaddr'])) {
1336         $type->lti_instructorchoicesendemailaddr = $config['instructorchoicesendemailaddr'];
1337     }
1338     if (isset($config['acceptgrades'])) {
1339         $type->lti_acceptgrades = $config['acceptgrades'];
1340     }
1341     if (isset($config['instructorchoiceacceptgrades'])) {
1342         $type->lti_instructorchoiceacceptgrades = $config['instructorchoiceacceptgrades'];
1343     }
1344     if (isset($config['allowroster'])) {
1345         $type->lti_allowroster = $config['allowroster'];
1346     }
1347     if (isset($config['instructorchoiceallowroster'])) {
1348         $type->lti_instructorchoiceallowroster = $config['instructorchoiceallowroster'];
1349     }
1350
1351     if (isset($config['customparameters'])) {
1352         $type->lti_customparameters = $config['customparameters'];
1353     }
1354
1355     if (isset($config['forcessl'])) {
1356         $type->lti_forcessl = $config['forcessl'];
1357     }
1358
1359     if (isset($config['organizationid'])) {
1360         $type->lti_organizationid = $config['organizationid'];
1361     }
1362     if (isset($config['organizationurl'])) {
1363         $type->lti_organizationurl = $config['organizationurl'];
1364     }
1365     if (isset($config['organizationdescr'])) {
1366         $type->lti_organizationdescr = $config['organizationdescr'];
1367     }
1368     if (isset($config['launchcontainer'])) {
1369         $type->lti_launchcontainer = $config['launchcontainer'];
1370     }
1371
1372     if (isset($config['coursevisible'])) {
1373         $type->lti_coursevisible = $config['coursevisible'];
1374     }
1375
1376     if (isset($config['debuglaunch'])) {
1377         $type->lti_debuglaunch = $config['debuglaunch'];
1378     }
1379
1380     if (isset($config['module_class_type'])) {
1381         $type->lti_module_class_type = $config['module_class_type'];
1382     }
1383
1384     return $type;
1385 }
1386
1387 function lti_prepare_type_for_save($type, $config) {
1388     if (isset($config->lti_toolurl)) {
1389         $type->baseurl = $config->lti_toolurl;
1390         $type->tooldomain = lti_get_domain_from_url($config->lti_toolurl);
1391     }
1392     if (isset($config->lti_typename)) {
1393         $type->name = $config->lti_typename;
1394     }
1395     $type->coursevisible = !empty($config->lti_coursevisible) ? $config->lti_coursevisible : 0;
1396     $config->lti_coursevisible = $type->coursevisible;
1397
1398     if (isset($config->lti_icon)) {
1399         $type->icon = $config->lti_icon;
1400     }
1401     if (isset($config->lti_secureicon)) {
1402         $type->secureicon = $config->lti_secureicon;
1403     }
1404
1405     if (isset($config->lti_forcessl)) {
1406         $type->forcessl = !empty($config->lti_forcessl) ? $config->lti_forcessl : 0;
1407         $config->lti_forcessl = $type->forcessl;
1408     }
1409
1410     $type->timemodified = time();
1411
1412     unset ($config->lti_typename);
1413     unset ($config->lti_toolurl);
1414     unset ($config->lti_icon);
1415     unset ($config->lti_secureicon);
1416 }
1417
1418 function lti_update_type($type, $config) {
1419     global $DB, $CFG;
1420
1421     lti_prepare_type_for_save($type, $config);
1422
1423     $clearcache = false;
1424     if (lti_request_is_using_ssl() && !empty($type->secureicon)) {
1425         $clearcache = !isset($config->oldicon) || ($config->oldicon !== $type->secureicon);
1426     } else {
1427         $clearcache = isset($type->icon) && (!isset($config->oldicon) || ($config->oldicon !== $type->icon));
1428     }
1429     unset($config->oldicon);
1430
1431     if ($DB->update_record('lti_types', $type)) {
1432         foreach ($config as $key => $value) {
1433             if (substr($key, 0, 4) == 'lti_' && !is_null($value)) {
1434                 $record = new \StdClass();
1435                 $record->typeid = $type->id;
1436                 $record->name = substr($key, 4);
1437                 $record->value = $value;
1438                 lti_update_config($record);
1439             }
1440         }
1441         require_once($CFG->libdir.'/modinfolib.php');
1442         if ($clearcache) {
1443             rebuild_course_cache();
1444         }
1445     }
1446 }
1447
1448 function lti_add_type($type, $config) {
1449     global $USER, $SITE, $DB;
1450
1451     lti_prepare_type_for_save($type, $config);
1452
1453     if (!isset($type->state)) {
1454         $type->state = LTI_TOOL_STATE_PENDING;
1455     }
1456
1457     if (!isset($type->timecreated)) {
1458         $type->timecreated = time();
1459     }
1460
1461     if (!isset($type->createdby)) {
1462         $type->createdby = $USER->id;
1463     }
1464
1465     if (!isset($type->course)) {
1466         $type->course = $SITE->id;
1467     }
1468
1469     // Create a salt value to be used for signing passed data to extension services
1470     // The outcome service uses the service salt on the instance. This can be used
1471     // for communication with services not related to a specific LTI instance.
1472     $config->lti_servicesalt = uniqid('', true);
1473
1474     $id = $DB->insert_record('lti_types', $type);
1475
1476     if ($id) {
1477         foreach ($config as $key => $value) {
1478             if (substr($key, 0, 4) == 'lti_' && !is_null($value)) {
1479                 $record = new \StdClass();
1480                 $record->typeid = $id;
1481                 $record->name = substr($key, 4);
1482                 $record->value = $value;
1483
1484                 lti_add_config($record);
1485             }
1486         }
1487     }
1488
1489     return $id;
1490 }
1491
1492 /**
1493  * Given an array of tool proxies, filter them based on their state
1494  *
1495  * @param array $toolproxies An array of lti_tool_proxies records
1496  * @param int $state One of the LTI_TOOL_PROXY_STATE_* constants
1497  *
1498  * @return array
1499  */
1500 function lti_filter_tool_proxy_types(array $toolproxies, $state) {
1501     $return = array();
1502     foreach ($toolproxies as $key => $toolproxy) {
1503         if ($toolproxy->state == $state) {
1504             $return[$key] = $toolproxy;
1505         }
1506     }
1507     return $return;
1508 }
1509
1510 /**
1511  * Get the tool proxy instance given its GUID
1512  *
1513  * @param string  $toolproxyguid   Tool proxy GUID value
1514  *
1515  * @return object
1516  */
1517 function lti_get_tool_proxy_from_guid($toolproxyguid) {
1518     global $DB;
1519
1520     $toolproxy = $DB->get_record('lti_tool_proxies', array('guid' => $toolproxyguid));
1521
1522     return $toolproxy;
1523 }
1524
1525 /**
1526  * Generates some of the tool proxy configuration based on the admin configuration details
1527  *
1528  * @param int $id
1529  *
1530  * @return Tool Proxy details
1531  */
1532 function lti_get_tool_proxy($id) {
1533     global $DB;
1534
1535     $toolproxy = $DB->get_record('lti_tool_proxies', array('id' => $id));
1536     return $toolproxy;
1537 }
1538
1539 /**
1540  * Generates some of the tool proxy configuration based on the admin configuration details
1541  *
1542  * @param int $id
1543  *
1544  * @return Tool Proxy details
1545  */
1546 function lti_get_tool_proxy_config($id) {
1547     $toolproxy = lti_get_tool_proxy($id);
1548
1549     $tp = new \stdClass();
1550     $tp->lti_registrationname = $toolproxy->name;
1551     $tp->toolproxyid = $toolproxy->id;
1552     $tp->state = $toolproxy->state;
1553     $tp->lti_registrationurl = $toolproxy->regurl;
1554     $tp->lti_capabilities = explode("\n", $toolproxy->capabilityoffered);
1555     $tp->lti_services = explode("\n", $toolproxy->serviceoffered);
1556
1557     return $tp;
1558 }
1559
1560 /**
1561  * Update the database with a tool proxy instance
1562  *
1563  * @param object   $config    Tool proxy definition
1564  *
1565  * @return int  Record id number
1566  */
1567 function lti_add_tool_proxy($config) {
1568     global $USER, $DB;
1569
1570     $toolproxy = new \stdClass();
1571     if (isset($config->lti_registrationname)) {
1572         $toolproxy->name = trim($config->lti_registrationname);
1573     }
1574     if (isset($config->lti_registrationurl)) {
1575         $toolproxy->regurl = trim($config->lti_registrationurl);
1576     }
1577     if (isset($config->lti_capabilities)) {
1578         $toolproxy->capabilityoffered = implode("\n", $config->lti_capabilities);
1579     }
1580     if (isset($config->lti_services)) {
1581         $toolproxy->serviceoffered = implode("\n", $config->lti_services);
1582     }
1583     if (isset($config->toolproxyid) && !empty($config->toolproxyid)) {
1584         $toolproxy->id = $config->toolproxyid;
1585         if (!isset($toolproxy->state) || ($toolproxy->state != LTI_TOOL_PROXY_STATE_ACCEPTED)) {
1586             $toolproxy->state = LTI_TOOL_PROXY_STATE_CONFIGURED;
1587             $toolproxy->guid = random_string();
1588             $toolproxy->secret = random_string();
1589         }
1590         $id = lti_update_tool_proxy($toolproxy);
1591     } else {
1592         $toolproxy->state = LTI_TOOL_PROXY_STATE_CONFIGURED;
1593         $toolproxy->timemodified = time();
1594         $toolproxy->timecreated = $toolproxy->timemodified;
1595         if (!isset($toolproxy->createdby)) {
1596             $toolproxy->createdby = $USER->id;
1597         }
1598         $toolproxy->guid = random_string();
1599         $toolproxy->secret = random_string();
1600         $id = $DB->insert_record('lti_tool_proxies', $toolproxy);
1601     }
1602
1603     return $id;
1604 }
1605
1606 /**
1607  * Updates a tool proxy in the database
1608  *
1609  * @param object  $toolproxy   Tool proxy
1610  *
1611  * @return int    Record id number
1612  */
1613 function lti_update_tool_proxy($toolproxy) {
1614     global $DB;
1615
1616     $toolproxy->timemodified = time();
1617     $id = $DB->update_record('lti_tool_proxies', $toolproxy);
1618
1619     return $id;
1620 }
1621
1622 /**
1623  * Delete a Tool Proxy
1624  *
1625  * @param int $id   Tool Proxy id
1626  */
1627 function lti_delete_tool_proxy($id) {
1628     global $DB;
1629     $DB->delete_records('lti_tool_settings', array('toolproxyid' => $id));
1630     $tools = $DB->get_records('lti_types', array('toolproxyid' => $id));
1631     foreach ($tools as $tool) {
1632         lti_delete_type($tool->id);
1633     }
1634     $DB->delete_records('lti_tool_proxies', array('id' => $id));
1635 }
1636
1637 /**
1638  * Add a tool configuration in the database
1639  *
1640  * @param object $config   Tool configuration
1641  *
1642  * @return int Record id number
1643  */
1644 function lti_add_config($config) {
1645     global $DB;
1646
1647     return $DB->insert_record('lti_types_config', $config);
1648 }
1649
1650 /**
1651  * Updates a tool configuration in the database
1652  *
1653  * @param object  $config   Tool configuration
1654  *
1655  * @return Record id number
1656  */
1657 function lti_update_config($config) {
1658     global $DB;
1659
1660     $return = true;
1661     $old = $DB->get_record('lti_types_config', array('typeid' => $config->typeid, 'name' => $config->name));
1662
1663     if ($old) {
1664         $config->id = $old->id;
1665         $return = $DB->update_record('lti_types_config', $config);
1666     } else {
1667         $return = $DB->insert_record('lti_types_config', $config);
1668     }
1669     return $return;
1670 }
1671
1672 /**
1673  * Gets the tool settings
1674  *
1675  * @param int  $toolproxyid   Id of tool proxy record
1676  * @param int  $courseid      Id of course (null if system settings)
1677  * @param int  $instanceid    Id of course module (null if system or context settings)
1678  *
1679  * @return array  Array settings
1680  */
1681 function lti_get_tool_settings($toolproxyid, $courseid = null, $instanceid = null) {
1682     global $DB;
1683
1684     $settings = array();
1685     $settingsstr = $DB->get_field('lti_tool_settings', 'settings', array('toolproxyid' => $toolproxyid,
1686         'course' => $courseid, 'coursemoduleid' => $instanceid));
1687     if ($settingsstr !== false) {
1688         $settings = json_decode($settingsstr, true);
1689     }
1690     return $settings;
1691 }
1692
1693 /**
1694  * Sets the tool settings (
1695  *
1696  * @param array  $settings      Array of settings
1697  * @param int    $toolproxyid   Id of tool proxy record
1698  * @param int    $courseid      Id of course (null if system settings)
1699  * @param int    $instanceid    Id of course module (null if system or context settings)
1700  */
1701 function lti_set_tool_settings($settings, $toolproxyid, $courseid = null, $instanceid = null) {
1702     global $DB;
1703
1704     $json = json_encode($settings);
1705     $record = $DB->get_record('lti_tool_settings', array('toolproxyid' => $toolproxyid,
1706         'course' => $courseid, 'coursemoduleid' => $instanceid));
1707     if ($record !== false) {
1708         $DB->update_record('lti_tool_settings', array('id' => $record->id, 'settings' => $json, 'timemodified' => time()));
1709     } else {
1710         $record = new \stdClass();
1711         $record->toolproxyid = $toolproxyid;
1712         $record->course = $courseid;
1713         $record->coursemoduleid = $instanceid;
1714         $record->settings = $json;
1715         $record->timecreated = time();
1716         $record->timemodified = $record->timecreated;
1717         $DB->insert_record('lti_tool_settings', $record);
1718     }
1719 }
1720
1721 /**
1722  * Signs the petition to launch the external tool using OAuth
1723  *
1724  * @param $oldparms     Parameters to be passed for signing
1725  * @param $endpoint     url of the external tool
1726  * @param $method       Method for sending the parameters (e.g. POST)
1727  * @param $oauth_consumoer_key          Key
1728  * @param $oauth_consumoer_secret       Secret
1729  */
1730 function lti_sign_parameters($oldparms, $endpoint, $method, $oauthconsumerkey, $oauthconsumersecret) {
1731
1732     $parms = $oldparms;
1733
1734     $testtoken = '';
1735
1736     // TODO: Switch to core oauthlib once implemented - MDL-30149.
1737     $hmacmethod = new lti\OAuthSignatureMethod_HMAC_SHA1();
1738     $testconsumer = new lti\OAuthConsumer($oauthconsumerkey, $oauthconsumersecret, null);
1739     $accreq = lti\OAuthRequest::from_consumer_and_token($testconsumer, $testtoken, $method, $endpoint, $parms);
1740     $accreq->sign_request($hmacmethod, $testconsumer, $testtoken);
1741
1742     $newparms = $accreq->get_parameters();
1743
1744     return $newparms;
1745 }
1746
1747 /**
1748  * Posts the launch petition HTML
1749  *
1750  * @param $newparms     Signed parameters
1751  * @param $endpoint     URL of the external tool
1752  * @param $debug        Debug (true/false)
1753  */
1754 function lti_post_launch_html($newparms, $endpoint, $debug=false) {
1755     $r = "<form action=\"" . $endpoint .
1756         "\" name=\"ltiLaunchForm\" id=\"ltiLaunchForm\" method=\"post\" encType=\"application/x-www-form-urlencoded\">\n";
1757
1758     // Contruct html for the launch parameters.
1759     foreach ($newparms as $key => $value) {
1760         $key = htmlspecialchars($key);
1761         $value = htmlspecialchars($value);
1762         if ( $key == "ext_submit" ) {
1763             $r .= "<input type=\"submit\"";
1764         } else {
1765             $r .= "<input type=\"hidden\" name=\"{$key}\"";
1766         }
1767         $r .= " value=\"";
1768         $r .= $value;
1769         $r .= "\"/>\n";
1770     }
1771
1772     if ( $debug ) {
1773         $r .= "<script language=\"javascript\"> \n";
1774         $r .= "  //<![CDATA[ \n";
1775         $r .= "function basicltiDebugToggle() {\n";
1776         $r .= "    var ele = document.getElementById(\"basicltiDebug\");\n";
1777         $r .= "    if (ele.style.display == \"block\") {\n";
1778         $r .= "        ele.style.display = \"none\";\n";
1779         $r .= "    }\n";
1780         $r .= "    else {\n";
1781         $r .= "        ele.style.display = \"block\";\n";
1782         $r .= "    }\n";
1783         $r .= "} \n";
1784         $r .= "  //]]> \n";
1785         $r .= "</script>\n";
1786         $r .= "<a id=\"displayText\" href=\"javascript:basicltiDebugToggle();\">";
1787         $r .= get_string("toggle_debug_data", "lti")."</a>\n";
1788         $r .= "<div id=\"basicltiDebug\" style=\"display:none\">\n";
1789         $r .= "<b>".get_string("basiclti_endpoint", "lti")."</b><br/>\n";
1790         $r .= $endpoint . "<br/>\n&nbsp;<br/>\n";
1791         $r .= "<b>".get_string("basiclti_parameters", "lti")."</b><br/>\n";
1792         foreach ($newparms as $key => $value) {
1793             $key = htmlspecialchars($key);
1794             $value = htmlspecialchars($value);
1795             $r .= "$key = $value<br/>\n";
1796         }
1797         $r .= "&nbsp;<br/>\n";
1798         $r .= "</div>\n";
1799     }
1800     $r .= "</form>\n";
1801
1802     if ( ! $debug ) {
1803         $r .= " <script type=\"text/javascript\"> \n" .
1804             "  //<![CDATA[ \n" .
1805             "    document.ltiLaunchForm.submit(); \n" .
1806             "  //]]> \n" .
1807             " </script> \n";
1808     }
1809     return $r;
1810 }
1811
1812 function lti_get_type($typeid) {
1813     global $DB;
1814
1815     return $DB->get_record('lti_types', array('id' => $typeid));
1816 }
1817
1818 function lti_get_launch_container($lti, $toolconfig) {
1819     if (empty($lti->launchcontainer)) {
1820         $lti->launchcontainer = LTI_LAUNCH_CONTAINER_DEFAULT;
1821     }
1822
1823     if ($lti->launchcontainer == LTI_LAUNCH_CONTAINER_DEFAULT) {
1824         if (isset($toolconfig['launchcontainer'])) {
1825             $launchcontainer = $toolconfig['launchcontainer'];
1826         }
1827     } else {
1828         $launchcontainer = $lti->launchcontainer;
1829     }
1830
1831     if (empty($launchcontainer) || $launchcontainer == LTI_LAUNCH_CONTAINER_DEFAULT) {
1832         $launchcontainer = LTI_LAUNCH_CONTAINER_EMBED_NO_BLOCKS;
1833     }
1834
1835     $devicetype = core_useragent::get_device_type();
1836
1837     // Scrolling within the object element doesn't work on iOS or Android
1838     // Opening the popup window also had some issues in testing
1839     // For mobile devices, always take up the entire screen to ensure the best experience.
1840     if ($devicetype === core_useragent::DEVICETYPE_MOBILE || $devicetype === core_useragent::DEVICETYPE_TABLET ) {
1841         $launchcontainer = LTI_LAUNCH_CONTAINER_REPLACE_MOODLE_WINDOW;
1842     }
1843
1844     return $launchcontainer;
1845 }
1846
1847 function lti_request_is_using_ssl() {
1848     global $CFG;
1849     return (stripos($CFG->httpswwwroot, 'https://') === 0);
1850 }
1851
1852 function lti_ensure_url_is_https($url) {
1853     if (!strstr($url, '://')) {
1854         $url = 'https://' . $url;
1855     } else {
1856         // If the URL starts with http, replace with https.
1857         if (stripos($url, 'http://') === 0) {
1858             $url = 'https://' . substr($url, 7);
1859         }
1860     }
1861
1862     return $url;
1863 }
1864
1865 /**
1866  * Determines if we should try to log the request
1867  *
1868  * @param string $rawbody
1869  * @return bool
1870  */
1871 function lti_should_log_request($rawbody) {
1872     global $CFG;
1873
1874     if (empty($CFG->mod_lti_log_users)) {
1875         return false;
1876     }
1877
1878     $logusers = explode(',', $CFG->mod_lti_log_users);
1879     if (empty($logusers)) {
1880         return false;
1881     }
1882
1883     try {
1884         $xml = new \SimpleXMLElement($rawbody);
1885         $ns  = $xml->getNamespaces();
1886         $ns  = array_shift($ns);
1887         $xml->registerXPathNamespace('lti', $ns);
1888         $requestuserid = '';
1889         if ($node = $xml->xpath('//lti:userId')) {
1890             $node = $node[0];
1891             $requestuserid = clean_param((string) $node, PARAM_INT);
1892         } else if ($node = $xml->xpath('//lti:sourcedId')) {
1893             $node = $node[0];
1894             $resultjson = json_decode((string) $node);
1895             $requestuserid = clean_param($resultjson->data->userid, PARAM_INT);
1896         }
1897     } catch (Exception $e) {
1898         return false;
1899     }
1900
1901     if (empty($requestuserid) or !in_array($requestuserid, $logusers)) {
1902         return false;
1903     }
1904
1905     return true;
1906 }
1907
1908 /**
1909  * Logs the request to a file in temp dir
1910  *
1911  * @param string $rawbody
1912  */
1913 function lti_log_request($rawbody) {
1914     if ($tempdir = make_temp_directory('mod_lti', false)) {
1915         if ($tempfile = tempnam($tempdir, 'mod_lti_request'.date('YmdHis'))) {
1916             file_put_contents($tempfile, $rawbody);
1917             chmod($tempfile, 0644);
1918         }
1919     }
1920 }
1921
1922 /**
1923  * Fetches LTI type configuration for an LTI instance
1924  *
1925  * @param stdClass $instance
1926  * @return array Can be empty if no type is found
1927  */
1928 function lti_get_type_config_by_instance($instance) {
1929     $typeid = null;
1930     if (empty($instance->typeid)) {
1931         $tool = lti_get_tool_by_url_match($instance->toolurl, $instance->course);
1932         if ($tool) {
1933             $typeid = $tool->id;
1934         }
1935     } else {
1936         $typeid = $instance->typeid;
1937     }
1938     if (!empty($typeid)) {
1939         return lti_get_type_config($typeid);
1940     }
1941     return array();
1942 }
1943
1944 /**
1945  * Enforce type config settings onto the LTI instance
1946  *
1947  * @param stdClass $instance
1948  * @param array $typeconfig
1949  */
1950 function lti_force_type_config_settings($instance, array $typeconfig) {
1951     $forced = array(
1952         'instructorchoicesendname'      => 'sendname',
1953         'instructorchoicesendemailaddr' => 'sendemailaddr',
1954         'instructorchoiceacceptgrades'  => 'acceptgrades',
1955     );
1956
1957     foreach ($forced as $instanceparam => $typeconfigparam) {
1958         if (array_key_exists($typeconfigparam, $typeconfig) && $typeconfig[$typeconfigparam] != LTI_SETTING_DELEGATE) {
1959             $instance->$instanceparam = $typeconfig[$typeconfigparam];
1960         }
1961     }
1962 }
1963
1964 /**
1965  * Initializes an array with the capabilities supported by the LTI module
1966  *
1967  * @return array List of capability names (without a dollar sign prefix)
1968  */
1969 function lti_get_capabilities() {
1970
1971     $capabilities = array(
1972        'basic-lti-launch-request' => '',
1973        'Context.id' => 'context_id',
1974        'CourseSection.title' => 'context_title',
1975        'CourseSection.label' => 'context_label',
1976        'CourseSection.sourcedId' => 'lis_course_section_sourcedid',
1977        'CourseSection.longDescription' => '$COURSE->summary',
1978        'CourseSection.timeFrame.begin' => '$COURSE->startdate',
1979        'ResourceLink.id' => 'resource_link_id',
1980        'ResourceLink.title' => 'resource_link_title',
1981        'ResourceLink.description' => 'resource_link_description',
1982        'User.id' => 'user_id',
1983        'User.username' => '$USER->username',
1984        'Person.name.full' => 'lis_person_name_full',
1985        'Person.name.given' => 'lis_person_name_given',
1986        'Person.name.family' => 'lis_person_name_family',
1987        'Person.email.primary' => 'lis_person_contact_email_primary',
1988        'Person.sourcedId' => 'lis_person_sourcedid',
1989        'Person.name.middle' => '$USER->middlename',
1990        'Person.address.street1' => '$USER->address',
1991        'Person.address.locality' => '$USER->city',
1992        'Person.address.country' => '$USER->country',
1993        'Person.address.timezone' => '$USER->timezone',
1994        'Person.phone.primary' => '$USER->phone1',
1995        'Person.phone.mobile' => '$USER->phone2',
1996        'Person.webaddress' => '$USER->url',
1997        'Membership.role' => 'roles',
1998        'Result.sourcedId' => 'lis_result_sourcedid',
1999        'Result.autocreate' => 'lis_outcome_service_url');
2000
2001     return $capabilities;
2002
2003 }
2004
2005 /**
2006  * Initializes an array with the services supported by the LTI module
2007  *
2008  * @return array List of services
2009  */
2010 function lti_get_services() {
2011
2012     $services = array();
2013     $definedservices = core_component::get_plugin_list('ltiservice');
2014     foreach ($definedservices as $name => $location) {
2015         $classname = "\\ltiservice_{$name}\\local\\service\\{$name}";
2016         $services[] = new $classname();
2017     }
2018
2019     return $services;
2020
2021 }
2022
2023 /**
2024  * Initializes an instance of the named service
2025  *
2026  * @param string $servicename Name of service
2027  *
2028  * @return mod_lti\local\ltiservice\service_base Service
2029  */
2030 function lti_get_service_by_name($servicename) {
2031
2032     $service = false;
2033     $classname = "\\ltiservice_{$servicename}\\local\\service\\{$servicename}";
2034     if (class_exists($classname)) {
2035         $service = new $classname();
2036     }
2037
2038     return $service;
2039
2040 }
2041
2042 /**
2043  * Finds a service by id
2044  *
2045  * @param array  $services    Array of services
2046  * @param string $resourceid  ID of resource
2047  *
2048  * @return mod_lti\local\ltiservice\service_base Service
2049  */
2050 function lti_get_service_by_resource_id($services, $resourceid) {
2051
2052     $service = false;
2053     foreach ($services as $aservice) {
2054         foreach ($aservice->get_resources() as $resource) {
2055             if ($resource->get_id() === $resourceid) {
2056                 $service = $aservice;
2057                 break 2;
2058             }
2059         }
2060     }
2061
2062     return $service;
2063
2064 }
2065
2066 /**
2067  * Extracts the named contexts from a tool proxy
2068  *
2069  * @param object $json
2070  *
2071  * @return array Contexts
2072  */
2073 function lti_get_contexts($json) {
2074
2075     $contexts = array();
2076     if (isset($json->{'@context'})) {
2077         foreach ($json->{'@context'} as $context) {
2078             if (is_object($context)) {
2079                 $contexts = array_merge(get_object_vars($context), $contexts);
2080             }
2081         }
2082     }
2083
2084     return $contexts;
2085
2086 }
2087
2088 /**
2089  * Converts an ID to a fully-qualified ID
2090  *
2091  * @param array $contexts
2092  * @param string $id
2093  *
2094  * @return string Fully-qualified ID
2095  */
2096 function lti_get_fqid($contexts, $id) {
2097
2098     $parts = explode(':', $id, 2);
2099     if (count($parts) > 1) {
2100         if (array_key_exists($parts[0], $contexts)) {
2101             $id = $contexts[$parts[0]] . $parts[1];
2102         }
2103     }
2104
2105     return $id;
2106
2107 }