lib/completionlib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * Contains a class used for tracking whether activities have been completed
  20  * by students ('completion')
  21  *
  22  * Completion top-level options (admin setting enablecompletion)
  23  *
  24  * @package    core
  25  * @subpackage completion
  26  * @copyright  1999 onwards Martin Dougiamas   {@link http://moodle.com}
  27  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  28  */
  29
  30 defined('MOODLE_INTERNAL') || die();
  31
  32 require_once $CFG->libdir.'/completion/completion_aggregation.php';
  33 require_once $CFG->libdir.'/completion/completion_criteria.php';
  34 require_once $CFG->libdir.'/completion/completion_completion.php';
  35 require_once $CFG->libdir.'/completion/completion_criteria_completion.php';
  36
  37
  38 /** The completion system is enabled in this site/course */
  39 define('COMPLETION_ENABLED', 1);
  40 /** The completion system is not enabled in this site/course */
  41 define('COMPLETION_DISABLED', 0);
  42
  43 // Completion tracking options per-activity (course_modules/completion)
  44
  45 /** Completion tracking is disabled for this activity */
  46 define('COMPLETION_TRACKING_NONE', 0);
  47 /** Manual completion tracking (user ticks box) is enabled for this activity */
  48 define('COMPLETION_TRACKING_MANUAL', 1);
  49 /** Automatic completion tracking (system ticks box) is enabled for this activity */
  50 define('COMPLETION_TRACKING_AUTOMATIC', 2);
  51
  52 // Completion state values (course_modules_completion/completionstate)
  53
  54 /** The user has not completed this activity. */
  55 define('COMPLETION_INCOMPLETE', 0);
  56 /** The user has completed this activity. It is not specified whether they have
  57  * passed or failed it. */
  58 define('COMPLETION_COMPLETE', 1);
  59 /** The user has completed this activity with a grade above the pass mark. */
  60 define('COMPLETION_COMPLETE_PASS', 2);
  61 /** The user has completed this activity but their grade is less than the pass mark */
  62 define('COMPLETION_COMPLETE_FAIL', 3);
  63
  64 // Completion effect changes (used only in update_state)
  65
  66 /** The effect of this change to completion status is unknown. */
  67 define('COMPLETION_UNKNOWN', -1);
  68 /** The user's grade has changed, so their new state might be
  69  * COMPLETION_COMPLETE_PASS or COMPLETION_COMPLETE_FAIL. */
  70 // TODO Is this useful?
  71 define('COMPLETION_GRADECHANGE', -2);
  72
  73 // Whether view is required to create an activity (course_modules/completionview)
  74
  75 /** User must view this activity */
  76 define('COMPLETION_VIEW_REQUIRED', 1);
  77 /** User does not need to view this activity */
  78 define('COMPLETION_VIEW_NOT_REQUIRED', 0);
  79
  80 // Completion viewed state (course_modules_completion/viewed)
  81
  82 /** User has viewed this activity */
  83 define('COMPLETION_VIEWED', 1);
  84 /** User has not viewed this activity */
  85 define('COMPLETION_NOT_VIEWED', 0);
  86
  87 // Completion cacheing
  88
  89 /** Cache expiry time in seconds (10 minutes) */
  90 define('COMPLETION_CACHE_EXPIRY', 10*60);
  91
  92 // Combining completion condition. This is also the value you should return
  93 // if you don't have any applicable conditions. Used for activity completion.
  94 /** Completion details should be ORed together and you should return false if
  95  none apply */
  96 define('COMPLETION_OR', false);
  97 /** Completion details should be ANDed together and you should return true if
  98  none apply */
  99 define('COMPLETION_AND', true);
 100
 101 // Course completion criteria aggregation methods
 102 define('COMPLETION_AGGREGATION_ALL',        1);
 103 define('COMPLETION_AGGREGATION_ANY',        2);
 104
 105
 106 /**
 107  * Class represents completion information for a course.
 108  *
 109  * Does not contain any data, so you can safely construct it multiple times
 110  * without causing any problems.
 111  *
 112  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 113  * @package moodlecore
 114  */
 115 class completion_info {
 116     /**
 117      * Course object passed during construction
 118      * @access  private
 119      * @var     object
 120      */
 121     private $course;
 122
 123     /**
 124      * Course id
 125      * @access  public
 126      * @var     int
 127      */
 128     public $course_id;
 129
 130     /**
 131      * Completion criteria
 132      * @access  private
 133      * @var     array
 134      * @see     completion_info->get_criteria()
 135      */
 136     private $criteria;
 137
 138     /**
 139      * Return array of aggregation methods
 140      * @access  public
 141      * @return  array
 142      */
 143     public static function get_aggregation_methods() {
 144         return array(
 145             COMPLETION_AGGREGATION_ALL       => get_string('all'),
 146             COMPLETION_AGGREGATION_ANY       => get_string('any', 'completion'),
 147         );
 148     }
 149
 150     /**
 151      * Constructs with course details.
 152      *
 153      * @param object $course Moodle course object. Must have at least ->id, ->enablecompletion
 154      */
 155     public function __construct($course) {
 156         $this->course = $course;
 157         $this->course_id = $course->id;
 158     }
 159
 160     /**
 161      * Determines whether completion is enabled across entire site.
 162      *
 163      * Static function.
 164      *
 165      * @global object
 166      * @return int COMPLETION_ENABLED (true) if completion is enabled for the site,
 167      *     COMPLETION_DISABLED (false) if it's complete
 168      */
 169     public static function is_enabled_for_site() {
 170         global $CFG;
 171         return !empty($CFG->enablecompletion);
 172     }
 173
 174     /**
 175      * Checks whether completion is enabled in a particular course and possibly
 176      * activity.
 177      *
 178      * @global object
 179      * @uses COMPLETION_DISABLED
 180      * @uses COMPLETION_ENABLED
 181      * @param object $cm Course-module object. If not specified, returns the course
 182      *   completion enable state.
 183      * @return mixed COMPLETION_ENABLED or COMPLETION_DISABLED (==0) in the case of
 184      *   site and course; COMPLETION_TRACKING_MANUAL, _AUTOMATIC or _NONE (==0)
 185      *   for a course-module.
 186      */
 187     public function is_enabled($cm=null) {
 188         global $CFG;
 189
 190         // First check global completion
 191         if (!isset($CFG->enablecompletion) || $CFG->enablecompletion == COMPLETION_DISABLED) {
 192             return COMPLETION_DISABLED;
 193         }
 194
 195         // Check course completion
 196         if ($this->course->enablecompletion == COMPLETION_DISABLED) {
 197             return COMPLETION_DISABLED;
 198         }
 199
 200         // If there was no $cm and we got this far, then it's enabled
 201         if (!$cm) {
 202             return COMPLETION_ENABLED;
 203         }
 204
 205         // Return course-module completion value
 206         return $cm->completion;
 207     }
 208
 209     /**
 210      * Displays the 'Your progress' help icon, if completion tracking is enabled.
 211      * Just prints the result of display_help_icon().
 212      * @deprecated Use display_help_icon instead.
 213      * @return void
 214      */
 215     public function print_help_icon() {
 216         print $this->display_help_icon();
 217     }
 218
 219     /**
 220      * Returns the 'Your progress' help icon, if completion tracking is enabled.
 221      * @global object
 222      * @return string HTML code for help icon, or blank if not needed
 223      */
 224     public function display_help_icon() {
 225         global $PAGE, $OUTPUT;
 226         $result = '';
 227         if ($this->is_enabled() && !$PAGE->user_is_editing() && isloggedin() && !isguestuser()) {
 228             $result .= '<span id = "completionprogressid" class="completionprogress">'.get_string('yourprogress','completion').' ';
 229             $result .= $OUTPUT->help_icon('completionicons', 'completion');
 230             $result .= '</span>';
 231         }
 232         return $result;
 233     }
 234
 235     /**
 236      * Get a course completion for a user
 237      * @access  public
 238      * @param   $user_id        int     User id
 239      * @param   $criteriatype   int     Specific criteria type to return
 240      * @return  false|completion_criteria_completion
 241      */
 242     public function get_completion($user_id, $criteriatype) {
 243         $completions = $this->get_completions($user_id, $criteriatype);
 244
 245         if (empty($completions)) {
 246             return false;
 247         } elseif (count($completions) > 1) {
 248             print_error('multipleselfcompletioncriteria', 'completion');
 249         }
 250
 251         return $completions[0];
 252     }
 253
 254     /**
 255      * Get all course criteria's completion objects for a user
 256      * @access  public
 257      * @param   $user_id        int     User id
 258      * @param   $criteriatype   int     optional    Specific criteria type to return
 259      * @return  array
 260      */
 261     public function get_completions($user_id, $criteriatype = null) {
 262         $criterion = $this->get_criteria($criteriatype);
 263
 264         $completions = array();
 265
 266         foreach ($criterion as $criteria) {
 267             $params = array(
 268                 'course'        => $this->course_id,
 269                 'userid'        => $user_id,
 270                 'criteriaid'    => $criteria->id
 271             );
 272
 273             $completion = new completion_criteria_completion($params);
 274             $completion->attach_criteria($criteria);
 275
 276             $completions[] = $completion;
 277         }
 278
 279         return $completions;
 280     }
 281
 282     /**
 283      * Get completion object for a user and a criteria
 284      * @access  public
 285      * @param   $user_id        int     User id
 286      * @param   $criteria       completion_criteria     Criteria object
 287      * @return  completion_criteria_completion
 288      */
 289     public function get_user_completion($user_id, $criteria) {
 290         $params = array(
 291             'criteriaid'    => $criteria->id,
 292             'userid'        => $user_id
 293         );
 294
 295         $completion = new completion_criteria_completion($params);
 296         return $completion;
 297     }
 298
 299     /**
 300      * Check if course has completion criteria set
 301      *
 302      * @access  public
 303      * @return  bool
 304      */
 305     public function has_criteria() {
 306         $criteria = $this->get_criteria();
 307
 308         return (bool) count($criteria);
 309     }
 310
 311
 312     /**
 313      * Get course completion criteria
 314      * @access  public
 315      * @param   $criteriatype   int     optional    Specific criteria type to return
 316      * @return  void
 317      */
 318     public function get_criteria($criteriatype = null) {
 319
 320         // Fill cache if empty
 321         if (!is_array($this->criteria)) {
 322             global $DB;
 323
 324             $params = array(
 325                 'course'    => $this->course->id
 326             );
 327
 328             // Load criteria from database
 329             $records = (array)$DB->get_records('course_completion_criteria', $params);
 330
 331             // Build array of criteria objects
 332             $this->criteria = array();
 333             foreach ($records as $record) {
 334                 $this->criteria[$record->id] = completion_criteria::factory($record);
 335             }
 336         }
 337
 338         // If after all criteria
 339         if ($criteriatype === null) {
 340             return $this->criteria;
 341         }
 342
 343         // If we are only after a specific criteria type
 344         $criteria = array();
 345         foreach ($this->criteria as $criterion) {
 346
 347             if ($criterion->criteriatype != $criteriatype) {
 348                 continue;
 349             }
 350
 351             $criteria[$criterion->id] = $criterion;
 352         }
 353
 354         return $criteria;
 355     }
 356
 357     /**
 358      * Get aggregation method
 359      * @access  public
 360      * @param   $criteriatype   int     optional    If none supplied, get overall aggregation method
 361      * @return  int
 362      */
 363     public function get_aggregation_method($criteriatype = null) {
 364         $params = array(
 365             'course'        => $this->course_id,
 366             'criteriatype'  => $criteriatype
 367         );
 368
 369         $aggregation = new completion_aggregation($params);
 370
 371         if (!$aggregation->id) {
 372             $aggregation->method = COMPLETION_AGGREGATION_ALL;
 373         }
 374
 375         return $aggregation->method;
 376     }
 377
 378     /**
 379      * Get incomplete course completion criteria
 380      * @access  public
 381      * @return  void
 382      */
 383     public function get_incomplete_criteria() {
 384         $incomplete = array();
 385
 386         foreach ($this->get_criteria() as $criteria) {
 387             if (!$criteria->is_complete()) {
 388                 $incomplete[] = $criteria;
 389             }
 390         }
 391
 392         return $incomplete;
 393     }
 394
 395     /**
 396      * Clear old course completion criteria
 397      */
 398     public function clear_criteria() {
 399         global $DB;
 400         $DB->delete_records('course_completion_criteria', array('course' => $this->course_id));
 401         $DB->delete_records('course_completion_aggr_methd', array('course' => $this->course_id));
 402
 403         $this->delete_course_completion_data();
 404     }
 405
 406     /**
 407      * Has the supplied user completed this course
 408      * @access  public
 409      * @param   $user_id    int     User's id
 410      * @return  boolean
 411      */
 412     public function is_course_complete($user_id) {
 413         $params = array(
 414             'userid'    => $user_id,
 415             'course'  => $this->course_id
 416         );
 417
 418         $ccompletion = new completion_completion($params);
 419         return $ccompletion->is_complete();
 420     }
 421
 422     /**
 423      * Updates (if necessary) the completion state of activity $cm for the given
 424      * user.
 425      *
 426      * For manual completion, this function is called when completion is toggled
 427      * with $possibleresult set to the target state.
 428      *
 429      * For automatic completion, this function should be called every time a module
 430      * does something which might influence a user's completion state. For example,
 431      * if a forum provides options for marking itself 'completed' once a user makes
 432      * N posts, this function should be called every time a user makes a new post.
 433      * [After the post has been saved to the database]. When calling, you do not
 434      * need to pass in the new completion state. Instead this function carries out
 435      * completion calculation by checking grades and viewed state itself, and
 436      * calling the involved module via modulename_get_completion_state() to check
 437      * module-specific conditions.
 438      *
 439      * @global object
 440      * @global object
 441      * @uses COMPLETION_COMPLETE
 442      * @uses COMPLETION_INCOMPLETE
 443      * @uses COMPLETION_COMPLETE_PASS
 444      * @uses COMPLETION_COMPLETE_FAIL
 445      * @uses COMPLETION_TRACKING_MANUAL
 446      * @param object $cm Course-module
 447      * @param int $possibleresult Expected completion result. If the event that
 448      *   has just occurred (e.g. add post) can only result in making the activity
 449      *   complete when it wasn't before, use COMPLETION_COMPLETE. If the event that
 450      *   has just occurred (e.g. delete post) can only result in making the activity
 451      *   not complete when it was previously complete, use COMPLETION_INCOMPLETE.
 452      *   Otherwise use COMPLETION_UNKNOWN. Setting this value to something other than
 453      *   COMPLETION_UNKNOWN significantly improves performance because it will abandon
 454      *   processing early if the user's completion state already matches the expected
 455      *   result. For manual events, COMPLETION_COMPLETE or COMPLETION_INCOMPLETE
 456      *   must be used; these directly set the specified state.
 457      * @param int $userid User ID to be updated. Default 0 = current user
 458      * @return void
 459      */
 460     public function update_state($cm, $possibleresult=COMPLETION_UNKNOWN, $userid=0) {
 461         global $USER, $SESSION;
 462
 463         // Do nothing if completion is not enabled for that activity
 464         if (!$this->is_enabled($cm)) {
 465             return;
 466         }
 467
 468         // Get current value of completion state and do nothing if it's same as
 469         // the possible result of this change. If the change is to COMPLETE and the
 470         // current value is one of the COMPLETE_xx subtypes, ignore that as well
 471         $current = $this->get_data($cm, false, $userid);
 472         if ($possibleresult == $current->completionstate ||
 473             ($possibleresult == COMPLETION_COMPLETE &&
 474                 ($current->completionstate == COMPLETION_COMPLETE_PASS ||
 475                 $current->completionstate == COMPLETION_COMPLETE_FAIL))) {
 476             return;
 477         }
 478
 479         if ($cm->completion == COMPLETION_TRACKING_MANUAL) {
 480             // For manual tracking we set the result directly
 481             switch($possibleresult) {
 482                 case COMPLETION_COMPLETE:
 483                 case COMPLETION_INCOMPLETE:
 484                     $newstate = $possibleresult;
 485                     break;
 486                 default:
 487                     $this->internal_systemerror("Unexpected manual completion state for {$cm->id}: $possibleresult");
 488             }
 489
 490         } else {
 491             // Automatic tracking; get new state
 492             $newstate = $this->internal_get_state($cm, $userid, $current);
 493         }
 494
 495         // If changed, update
 496         if ($newstate != $current->completionstate) {
 497             $current->completionstate = $newstate;
 498             $current->timemodified    = time();
 499             $this->internal_set_data($cm, $current);
 500         }
 501     }
 502
 503     /**
 504      * Calculates the completion state for an activity and user.
 505      *
 506      * Internal function. Not private, so we can unit-test it.
 507      *
 508      * @global object
 509      * @global object
 510      * @global object
 511      * @uses COMPLETION_VIEW_REQUIRED
 512      * @uses COMPLETION_NOT_VIEWED
 513      * @uses COMPLETION_INCOMPLETE
 514      * @uses FEATURE_COMPLETION_HAS_RULES
 515      * @uses COMPLETION_COMPLETE
 516      * @uses COMPLETION_AND
 517      * @param object $cm Activity
 518      * @param int $userid ID of user
 519      * @param object $current Previous completion information from database
 520      * @return mixed
 521      */
 522     function internal_get_state($cm, $userid, $current) {
 523         global $USER, $DB, $CFG;
 524
 525         // Get user ID
 526         if (!$userid) {
 527             $userid = $USER->id;
 528         }
 529
 530         // Check viewed
 531         if ($cm->completionview == COMPLETION_VIEW_REQUIRED &&
 532             $current->viewed == COMPLETION_NOT_VIEWED) {
 533
 534             return COMPLETION_INCOMPLETE;
 535         }
 536
 537         // Modname hopefully is provided in $cm but just in case it isn't, let's grab it
 538         if (!isset($cm->modname)) {
 539             $cm->modname = $DB->get_field('modules', 'name', array('id'=>$cm->module));
 540         }
 541
 542         $newstate = COMPLETION_COMPLETE;
 543
 544         // Check grade
 545         if (!is_null($cm->completiongradeitemnumber)) {
 546             require_once($CFG->libdir.'/gradelib.php');
 547             $item = grade_item::fetch(array('courseid'=>$cm->course, 'itemtype'=>'mod',
 548                 'itemmodule'=>$cm->modname, 'iteminstance'=>$cm->instance,
 549                 'itemnumber'=>$cm->completiongradeitemnumber));
 550             if ($item) {
 551                 // Fetch 'grades' (will be one or none)
 552                 $grades = grade_grade::fetch_users_grades($item, array($userid), false);
 553                 if (empty($grades)) {
 554                     // No grade for user
 555                     return COMPLETION_INCOMPLETE;
 556                 }
 557                 if (count($grades) > 1) {
 558                     $this->internal_systemerror("Unexpected result: multiple grades for
 559                         item '{$item->id}', user '{$userid}'");
 560                 }
 561                 $newstate = $this->internal_get_grade_state($item, reset($grades));
 562                 if ($newstate == COMPLETION_INCOMPLETE) {
 563                     return COMPLETION_INCOMPLETE;
 564                 }
 565
 566             } else {
 567                 $this->internal_systemerror("Cannot find grade item for '{$cm->modname}'
 568                     cm '{$cm->id}' matching number '{$cm->completiongradeitemnumber}'");
 569             }
 570         }
 571
 572         if (plugin_supports('mod', $cm->modname, FEATURE_COMPLETION_HAS_RULES)) {
 573             $function = $cm->modname.'_get_completion_state';
 574             if (!function_exists($function)) {
 575                 $this->internal_systemerror("Module {$cm->modname} claims to support
 576                     FEATURE_COMPLETION_HAS_RULES but does not have required
 577                     {$cm->modname}_get_completion_state function");
 578             }
 579             if (!$function($this->course, $cm, $userid, COMPLETION_AND)) {
 580                 return COMPLETION_INCOMPLETE;
 581             }
 582         }
 583
 584         return $newstate;
 585
 586     }
 587
 588
 589     /**
 590      * Marks a module as viewed.
 591      *
 592      * Should be called whenever a module is 'viewed' (it is up to the module how to
 593      * determine that). Has no effect if viewing is not set as a completion condition.
 594      *
 595      * Note that this function must be called before you print the page header because
 596      * it is possible that the navigation block may depend on it. If you call it after
 597      * printing the header, it shows a developer debug warning.
 598      * @uses COMPLETION_VIEW_NOT_REQUIRED
 599      * @uses COMPLETION_VIEWED
 600      * @uses COMPLETION_COMPLETE
 601      * @param object $cm Activity
 602      * @param int $userid User ID or 0 (default) for current user
 603      * @return void
 604      */
 605     public function set_module_viewed($cm, $userid=0) {
 606         global $PAGE, $UNITTEST;
 607         if ($PAGE->headerprinted && empty($UNITTEST->running)) {
 608             debugging('set_module_viewed must be called before header is printed',
 609                     DEBUG_DEVELOPER);
 610         }
 611         // Don't do anything if view condition is not turned on
 612         if ($cm->completionview == COMPLETION_VIEW_NOT_REQUIRED || !$this->is_enabled($cm)) {
 613             return;
 614         }
 615         // Get current completion state
 616         $data = $this->get_data($cm, $userid);
 617         // If we already viewed it, don't do anything
 618         if ($data->viewed == COMPLETION_VIEWED) {
 619             return;
 620         }
 621         // OK, change state, save it, and update completion
 622         $data->viewed = COMPLETION_VIEWED;
 623         $this->internal_set_data($cm, $data);
 624         $this->update_state($cm, COMPLETION_COMPLETE, $userid);
 625     }
 626
 627     /**
 628      * Determines how much completion data exists for an activity. This is used when
 629      * deciding whether completion information should be 'locked' in the module
 630      * editing form.
 631      *
 632      * @global object
 633      * @param object $cm Activity
 634      * @return int The number of users who have completion data stored for this
 635      *   activity, 0 if none
 636      */
 637     public function count_user_data($cm) {
 638         global $DB;
 639
 640         return $DB->get_field_sql("
 641     SELECT
 642         COUNT(1)
 643     FROM
 644         {course_modules_completion}
 645     WHERE
 646         coursemoduleid=? AND completionstate<>0", array($cm->id));
 647     }
 648
 649     /**
 650      * Determines how much course completion data exists for a course. This is used when
 651      * deciding whether completion information should be 'locked' in the completion
 652      * settings form and activity completion settings.
 653      *
 654      * @global object
 655      * @param  int $user_id Optionally only get course completion data for a single user
 656      * @return int The number of users who have completion data stored for this
 657      *   course, 0 if none
 658      */
 659     public function count_course_user_data($user_id = null) {
 660         global $DB;
 661
 662         $sql = '
 663     SELECT
 664         COUNT(1)
 665     FROM
 666         {course_completion_crit_compl}
 667     WHERE
 668         course = ?
 669         ';
 670
 671         $params = array($this->course_id);
 672
 673         // Limit data to a single user if an ID is supplied
 674         if ($user_id) {
 675             $sql .= ' AND userid = ?';
 676             $params[] = $user_id;
 677         }
 678
 679         return $DB->get_field_sql($sql, $params);
 680     }
 681
 682     /**
 683      * Check if this course's completion criteria should be locked
 684      *
 685      * @return  boolean
 686      */
 687     public function is_course_locked() {
 688         return (bool) $this->count_course_user_data();
 689     }
 690
 691     /**
 692      * Deletes all course completion completion data.
 693      *
 694      * Intended to be used when unlocking completion criteria settings.
 695      *
 696      * @global  object
 697      * @return  void
 698      */
 699     public function delete_course_completion_data() {
 700         global $DB;
 701
 702         $DB->delete_records('course_completions', array('course' => $this->course_id));
 703         $DB->delete_records('course_completion_crit_compl', array('course' => $this->course_id));
 704     }
 705
 706     /**
 707      * Deletes completion state related to an activity for all users.
 708      *
 709      * Intended for use only when the activity itself is deleted.
 710      *
 711      * @global object
 712      * @global object
 713      * @param object $cm Activity
 714      */
 715     public function delete_all_state($cm) {
 716         global $SESSION, $DB;
 717
 718         // Delete from database
 719         $DB->delete_records('course_modules_completion', array('coursemoduleid'=>$cm->id));
 720
 721         // Erase cache data for current user if applicable
 722         if (isset($SESSION->completioncache) &&
 723             array_key_exists($cm->course, $SESSION->completioncache) &&
 724             array_key_exists($cm->id, $SESSION->completioncache[$cm->course])) {
 725
 726             unset($SESSION->completioncache[$cm->course][$cm->id]);
 727         }
 728
 729         // Check if there is an associated course completion criteria
 730         $criteria = $this->get_criteria(COMPLETION_CRITERIA_TYPE_ACTIVITY);
 731         $acriteria = false;
 732         foreach ($criteria as $criterion) {
 733             if ($criterion->moduleinstance == $cm->id) {
 734                 $acriteria = $criterion;
 735                 break;
 736     }
 737         }
 738
 739         if ($acriteria) {
 740             // Delete all criteria completions relating to this activity
 741             $DB->delete_records('course_completion_crit_compl', array('course' => $this->course_id, 'criteriaid' => $acriteria->id));
 742             $DB->delete_records('course_completions', array('course' => $this->course_id));
 743         }
 744     }
 745
 746     /**
 747      * Recalculates completion state related to an activity for all users.
 748      *
 749      * Intended for use if completion conditions change. (This should be avoided
 750      * as it may cause some things to become incomplete when they were previously
 751      * complete, with the effect - for example - of hiding a later activity that
 752      * was previously available.)
 753      *
 754      * Resetting state of manual tickbox has same result as deleting state for
 755      * it.
 756      *
 757      * @global object
 758      * @uses COMPLETION_TRACKING_MANUAL
 759      * @uses COMPLETION_UNKNOWN
 760      * @param object $cm Activity
 761      */
 762     public function reset_all_state($cm) {
 763         global $DB;
 764
 765         if ($cm->completion == COMPLETION_TRACKING_MANUAL) {
 766             $this->delete_all_state($cm);
 767             return;
 768         }
 769         // Get current list of users with completion state
 770         $rs = $DB->get_recordset('course_modules_completion', array('coursemoduleid'=>$cm->id), '', 'userid');
 771         $keepusers = array();
 772         foreach ($rs as $rec) {
 773             $keepusers[] = $rec->userid;
 774         }
 775         $rs->close();
 776
 777         // Delete all existing state [also clears session cache for current user]
 778         $this->delete_all_state($cm);
 779
 780         // Merge this with list of planned users (according to roles)
 781         $trackedusers = $this->get_tracked_users();
 782         foreach ($trackedusers as $trackeduser) {
 783             $keepusers[] = $trackeduser->id;
 784         }
 785         $keepusers = array_unique($keepusers);
 786
 787         // Recalculate state for each kept user
 788         foreach ($keepusers as $keepuser) {
 789             $this->update_state($cm, COMPLETION_UNKNOWN, $keepuser);
 790         }
 791     }
 792
 793     /**
 794      * Obtains completion data for a particular activity and user (from the
 795      * session cache if available, or by SQL query)
 796      *
 797      * @global object
 798      * @global object
 799      * @global object
 800      * @global object
 801      * @uses COMPLETION_CACHE_EXPIRY
 802      * @param object $cm Activity; only required field is ->id
 803      * @param bool $wholecourse If true (default false) then, when necessary to
 804      *   fill the cache, retrieves information from the entire course not just for
 805      *   this one activity
 806      * @param int $userid User ID or 0 (default) for current user
 807      * @param array $modinfo Supply the value here - this is used for unit
 808      *   testing and so that it can be called recursively from within
 809      *   get_fast_modinfo. (Needs only list of all CMs with IDs.)
 810      *   Otherwise the method calls get_fast_modinfo itself.
 811      * @return object Completion data (record from course_modules_completion)
 812      */
 813     public function get_data($cm, $wholecourse=false, $userid=0, $modinfo=null) {
 814         global $USER, $CFG, $SESSION, $DB;
 815
 816         // Get user ID
 817         if (!$userid) {
 818             $userid = $USER->id;
 819         }
 820
 821         // Is this the current user?
 822         $currentuser = $userid==$USER->id;
 823
 824         if ($currentuser && is_object($SESSION)) {
 825             // Make sure cache is present and is for current user (loginas
 826             // changes this)
 827             if (!isset($SESSION->completioncache) || $SESSION->completioncacheuserid!=$USER->id) {
 828                 $SESSION->completioncache = array();
 829                 $SESSION->completioncacheuserid = $USER->id;
 830             }
 831             // Expire any old data from cache
 832             foreach ($SESSION->completioncache as $courseid=>$activities) {
 833                 if (empty($activities['updated']) || $activities['updated'] < time()-COMPLETION_CACHE_EXPIRY) {
 834                     unset($SESSION->completioncache[$courseid]);
 835                 }
 836             }
 837             // See if requested data is present, if so use cache to get it
 838             if (isset($SESSION->completioncache) &&
 839                 array_key_exists($this->course->id, $SESSION->completioncache) &&
 840                 array_key_exists($cm->id, $SESSION->completioncache[$this->course->id])) {
 841                 return $SESSION->completioncache[$this->course->id][$cm->id];
 842             }
 843         }
 844
 845         // Not there, get via SQL
 846         if ($currentuser && $wholecourse) {
 847             // Get whole course data for cache
 848             $alldatabycmc = $DB->get_records_sql("
 849     SELECT
 850         cmc.*
 851     FROM
 852         {course_modules} cm
 853         INNER JOIN {course_modules_completion} cmc ON cmc.coursemoduleid=cm.id
 854     WHERE
 855         cm.course=? AND cmc.userid=?", array($this->course->id, $userid));
 856
 857             // Reindex by cm id
 858             $alldata = array();
 859             if ($alldatabycmc) {
 860                 foreach ($alldatabycmc as $data) {
 861                     $alldata[$data->coursemoduleid] = $data;
 862                 }
 863             }
 864
 865             // Get the module info and build up condition info for each one
 866             if (empty($modinfo)) {
 867                 $modinfo = get_fast_modinfo($this->course, $userid);
 868             }
 869             foreach ($modinfo->cms as $othercm) {
 870                 if (array_key_exists($othercm->id, $alldata)) {
 871                     $data = $alldata[$othercm->id];
 872                 } else {
 873                     // Row not present counts as 'not complete'
 874                     $data = new StdClass;
 875                     $data->id              = 0;
 876                     $data->coursemoduleid  = $othercm->id;
 877                     $data->userid          = $userid;
 878                     $data->completionstate = 0;
 879                     $data->viewed          = 0;
 880                     $data->timemodified    = 0;
 881                 }
 882                 $SESSION->completioncache[$this->course->id][$othercm->id] = $data;
 883             }
 884             $SESSION->completioncache[$this->course->id]['updated'] = time();
 885
 886             if (!isset($SESSION->completioncache[$this->course->id][$cm->id])) {
 887                 $this->internal_systemerror("Unexpected error: course-module {$cm->id} could not be found on course {$this->course->id}");
 888             }
 889             return $SESSION->completioncache[$this->course->id][$cm->id];
 890
 891         } else {
 892             // Get single record
 893             $data = $DB->get_record('course_modules_completion', array('coursemoduleid'=>$cm->id, 'userid'=>$userid));
 894             if ($data == false) {
 895                 // Row not present counts as 'not complete'
 896                 $data = new StdClass;
 897                 $data->id              = 0;
 898                 $data->coursemoduleid  = $cm->id;
 899                 $data->userid          = $userid;
 900                 $data->completionstate = 0;
 901                 $data->viewed          = 0;
 902                 $data->timemodified    = 0;
 903             }
 904
 905             // Put in cache
 906             if ($currentuser) {
 907                 $SESSION->completioncache[$this->course->id][$cm->id] = $data;
 908                 // For single updates, only set date if it was empty before
 909                 if (empty($SESSION->completioncache[$this->course->id]['updated'])) {
 910                     $SESSION->completioncache[$this->course->id]['updated'] = time();
 911                 }
 912             }
 913         }
 914
 915         return $data;
 916     }
 917
 918     /**
 919      * Updates completion data for a particular coursemodule and user (user is
 920      * determined from $data).
 921      *
 922      * (Internal function. Not private, so we can unit-test it.)
 923      *
 924      * @global object
 925      * @global object
 926      * @global object
 927      * @param object $cm Activity
 928      * @param object $data Data about completion for that user
 929      */
 930     function internal_set_data($cm, $data) {
 931         global $USER, $SESSION, $DB;
 932
 933         if ($data->id) {
 934             // Has real (nonzero) id meaning that a database row exists
 935             $DB->update_record('course_modules_completion', $data);
 936         } else {
 937             // Didn't exist before, needs creating
 938             $data->id = $DB->insert_record('course_modules_completion', $data);
 939         }
 940
 941         if ($data->userid == $USER->id) {
 942             $SESSION->completioncache[$cm->course][$cm->id] = $data;
 943             $reset = 'reset';
 944             get_fast_modinfo($reset);
 945         }
 946     }
 947
 948     /**
 949      * Obtains a list of activities for which completion is enabled on the
 950      * course. The list is ordered by the section order of those activities.
 951      *
 952      * @global object
 953      * @uses COMPLETION_TRACKING_NONE
 954      * @param array $modinfo For unit testing only, supply the value
 955      *   here. Otherwise the method calls get_fast_modinfo
 956      * @return array Array from $cmid => $cm of all activities with completion enabled,
 957      *   empty array if none
 958      */
 959     public function get_activities($modinfo=null) {
 960         global $DB;
 961
 962         // Obtain those activities which have completion turned on
 963         $withcompletion = $DB->get_records_select('course_modules', 'course='.$this->course->id.
 964           ' AND completion<>'.COMPLETION_TRACKING_NONE);
 965         if (!$withcompletion) {
 966             return array();
 967         }
 968
 969         // Use modinfo to get section order and also add in names
 970         if (empty($modinfo)) {
 971             $modinfo = get_fast_modinfo($this->course);
 972         }
 973         $result = array();
 974         foreach ($modinfo->sections as $sectioncms) {
 975             foreach ($sectioncms as $cmid) {
 976                 if (array_key_exists($cmid, $withcompletion)) {
 977                     $result[$cmid] = $withcompletion[$cmid];
 978                     $result[$cmid]->modname = $modinfo->cms[$cmid]->modname;
 979                     $result[$cmid]->name    = $modinfo->cms[$cmid]->name;
 980                 }
 981             }
 982         }
 983
 984         return $result;
 985     }
 986
 987
 988     /**
 989      * Checks to see if the userid supplied has a tracked role in
 990      * this course
 991      *
 992      * @param   $userid     User id
 993      * @return  bool
 994      */
 995     function is_tracked_user($userid) {
 996         global $DB;
 997
 998         $tracked = $this->generate_tracked_user_sql();
 999
1000         $sql  = "SELECT u.id ";
1001         $sql .= $tracked->sql;
1002         $sql .= ' AND u.id = :userid';
1003
1004         $params = $tracked->data;
1005         $params['userid'] = (int)$userid;
1006         return $DB->record_exists_sql($sql, $params);
1007     }
1008
1009
1010     /**
1011      * Return number of users whose progress is tracked in this course
1012      *
1013      * Optionally supply a search's where clause, or a group id
1014      *
1015      * @param   string  $where          Where clause sql
1016      * @param   array   $where_params   Where clause params
1017      * @param   int     $groupid    Group id
1018      * @return  int
1019      */
1020     function get_num_tracked_users($where = '', $where_params = array(), $groupid = 0) {
1021         global $DB;
1022
1023         $tracked = $this->generate_tracked_user_sql($groupid);
1024
1025         $sql  = "SELECT COUNT(u.id) ";
1026         $sql .= $tracked->sql;
1027
1028         if ($where) {
1029             $sql .= " AND $where";
1030         }
1031
1032         $params = array_merge($tracked->data, $where_params);
1033         return $DB->count_records_sql($sql, $params);
1034     }
1035
1036
1037     /**
1038      * Return array of users whose progress is tracked in this course
1039      *
1040      * Optionally supply a search's where caluse, group id, sorting, paging
1041      *
1042      * @param   string      $where          Where clause sql (optional)
1043      * @param   array       $where_params   Where clause params (optional)
1044      * @param   integer     $groupid    Group ID to restrict to (optional)
1045      * @param   string      $sort       Order by clause (optional)
1046      * @param   integer     $limitfrom  Result start (optional)
1047      * @param   integer     $limitnum   Result max size (optional)
1048      * @return  array
1049      */
1050     function get_tracked_users($where = '', $where_params = array(), $groupid = 0,
1051              $sort = '', $limitfrom = '', $limitnum = '') {
1052
1053         global $DB;
1054
1055         $tracked = $this->generate_tracked_user_sql($groupid);
1056         $params = $tracked->data;
1057
1058         $sql = "
1059             SELECT
1060                 u.id,
1061                 u.firstname,
1062                 u.lastname,
1063                 u.idnumber
1064         ";
1065
1066         $sql .= $tracked->sql;
1067
1068         if ($where) {
1069             $sql .= " AND $where";
1070             $params = array_merge($params, $where_params);
1071         }
1072
1073         if ($sort) {
1074             $sql .= " ORDER BY $sort";
1075         }
1076
1077         $users = $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
1078         return $users ? $users : array(); // In case it returns false
1079     }
1080
1081
1082     /**
1083      * Generate the SQL for finding tracked users in this course
1084      *
1085      * Returns an object containing the sql fragment and an array of
1086      * bound data params.
1087      *
1088      * @param   integer $groupid
1089      * @return  object
1090      */
1091     function generate_tracked_user_sql($groupid = 0) {
1092         global $CFG;
1093
1094         $return = new stdClass();
1095         $return->sql = '';
1096         $return->data = array();
1097
1098         if (!empty($CFG->gradebookroles)) {
1099             $roles = ' AND ra.roleid IN ('.$CFG->gradebookroles.')';
1100         } else {
1101             // This causes it to default to everyone (if there is no student role)
1102             $roles = '';
1103         }
1104
1105         // Build context sql
1106         $context = get_context_instance(CONTEXT_COURSE, $this->course->id);
1107         $parentcontexts = substr($context->path, 1); // kill leading slash
1108         $parentcontexts = str_replace('/', ',', $parentcontexts);
1109         if ($parentcontexts !== '') {
1110             $parentcontexts = ' OR ra.contextid IN ('.$parentcontexts.' )';
1111         }
1112
1113         $groupjoin   = '';
1114         $groupselect = '';
1115         if ($groupid) {
1116             $groupjoin   = "JOIN {groups_members} gm
1117                               ON gm.userid = u.id";
1118             $groupselect = " AND gm.groupid = :groupid ";
1119
1120             $return->data['groupid'] = $groupid;
1121         }
1122
1123         $return->sql = "
1124             FROM
1125                 {user} u
1126             INNER JOIN
1127                 {role_assignments} ra
1128              ON ra.userid = u.id
1129             INNER JOIN
1130                 {role} r
1131              ON r.id = ra.roleid
1132             INNER JOIN
1133                 {user_enrolments} ue
1134              ON ue.userid = u.id
1135             INNER JOIN
1136                 {enrol} e
1137              ON e.id = ue.enrolid
1138             INNER JOIN
1139                 {course} c
1140              ON c.id = e.courseid
1141             $groupjoin
1142             WHERE
1143                 (ra.contextid = :contextid $parentcontexts)
1144             AND c.id = :courseid
1145             AND ue.status = 0
1146             AND e.status = 0
1147             AND ue.timestart < :now1
1148             AND (ue.timeend > :now2 OR ue.timeend = 0)
1149                 $groupselect
1150                 $roles
1151         ";
1152
1153         $now = time();
1154         $return->data['now1'] = $now;
1155         $return->data['now2'] = $now;
1156         $return->data['contextid'] = $context->id;
1157         $return->data['courseid'] = $this->course->id;
1158
1159         return $return;
1160     }
1161
1162     /**
1163      * Obtains progress information across a course for all users on that course, or
1164      * for all users in a specific group. Intended for use when displaying progress.
1165      *
1166      * This includes only users who, in course context, have one of the roles for
1167      * which progress is tracked (the gradebookroles admin option) and are enrolled in course.
1168      *
1169      * Users are included (in the first array) even if they do not have
1170      * completion progress for any course-module.
1171      *
1172      * @global object
1173      * @global object
1174      * @param bool $sortfirstname If true, sort by first name, otherwise sort by
1175      *   last name
1176      * @param string $where Where clause sql (optional)
1177      * @param array $where_params Where clause params (optional)
1178      * @param int $groupid Group ID or 0 (default)/false for all groups
1179      * @param int $pagesize Number of users to actually return (optional)
1180      * @param int $start User to start at if paging (optional)
1181      * @return Object with ->total and ->start (same as $start) and ->users;
1182      *   an array of user objects (like mdl_user id, firstname, lastname)
1183      *   containing an additional ->progress array of coursemoduleid => completionstate
1184      */
1185     public function get_progress_all($where = '', $where_params = array(), $groupid = 0,
1186                                        $sort = '', $pagesize = '', $start = '') {
1187         global $CFG, $DB;
1188
1189         // Get list of applicable users
1190         $users = $this->get_tracked_users($where, $where_params, $groupid, $sort, $start, $pagesize);
1191
1192         // Get progress information for these users in groups of 1, 000 (if needed)
1193         // to avoid making the SQL IN too long
1194         $results = array();
1195         $userids = array();
1196         foreach ($users as $user) {
1197             $userids[] = $user->id;
1198             $results[$user->id] = $user;
1199             $results[$user->id]->progress = array();
1200         }
1201
1202         for($i=0; $i<count($userids); $i+=1000) {
1203             $blocksize = count($userids)-$i < 1000 ? count($userids)-$i : 1000;
1204
1205             list($insql, $params) = $DB->get_in_or_equal(array_slice($userids, $i, $blocksize));
1206             array_splice($params, 0, 0, array($this->course->id));
1207             $rs = $DB->get_recordset_sql("
1208                 SELECT
1209                     cmc.*
1210                 FROM
1211                     {course_modules} cm
1212                     INNER JOIN {course_modules_completion} cmc ON cm.id=cmc.coursemoduleid
1213                 WHERE
1214                     cm.course=? AND cmc.userid $insql
1215     ", $params);
1216             foreach ($rs as $progress) {
1217                 $progress = (object)$progress;
1218                 $results[$progress->userid]->progress[$progress->coursemoduleid] = $progress;
1219             }
1220             $rs->close();
1221         }
1222
1223         return $results;
1224     }
1225
1226     /**
1227      * Called by grade code to inform the completion system when a grade has
1228      * been changed. If the changed grade is used to determine completion for
1229      * the course-module, then the completion status will be updated.
1230      *
1231      * @uses COMPLETION_TRACKING_MANUAL
1232      * @uses COMPLETION_INCOMPLETE
1233      * @param object $cm Course-module for item that owns grade
1234      * @param grade_item $item Grade item
1235      * @param object $grade
1236      * @param bool $deleted
1237      * @return void
1238      */
1239     public function inform_grade_changed($cm, $item, $grade, $deleted) {
1240         // Bail out now if completion is not enabled for course-module, it is enabled
1241         // but is set to manual, grade is not used to compute completion, or this
1242         // is a different numbered grade
1243         if (!$this->is_enabled($cm) ||
1244             $cm->completion == COMPLETION_TRACKING_MANUAL ||
1245             is_null($cm->completiongradeitemnumber) ||
1246             $item->itemnumber != $cm->completiongradeitemnumber) {
1247             return;
1248         }
1249
1250         // What is the expected result based on this grade?
1251         if ($deleted) {
1252             // Grade being deleted, so only change could be to make it incomplete
1253             $possibleresult = COMPLETION_INCOMPLETE;
1254         } else {
1255             $possibleresult = $this->internal_get_grade_state($item, $grade);
1256         }
1257
1258         // OK, let's update state based on this
1259         $this->update_state($cm, $possibleresult, $grade->userid);
1260     }
1261
1262     /**
1263      * Calculates the completion state that would result from a graded item
1264      * (where grade-based completion is turned on) based on the actual grade
1265      * and settings.
1266      *
1267      * Internal function. Not private, so we can unit-test it.
1268      *
1269      * @uses COMPLETION_INCOMPLETE
1270      * @uses COMPLETION_COMPLETE_PASS
1271      * @uses COMPLETION_COMPLETE_FAIL
1272      * @uses COMPLETION_COMPLETE
1273      * @param object $item grade_item
1274      * @param object $grade grade_grade
1275      * @return int Completion state e.g. COMPLETION_INCOMPLETE
1276      */
1277     function internal_get_grade_state($item, $grade) {
1278         if (!$grade) {
1279             return COMPLETION_INCOMPLETE;
1280         }
1281         // Conditions to show pass/fail:
1282         // a) Grade has pass mark (default is 0.00000 which is boolean true so be careful)
1283         // b) Grade is visible (neither hidden nor hidden-until)
1284         if ($item->gradepass && $item->gradepass > 0.000009 && !$item->hidden) {
1285             // Use final grade if set otherwise raw grade
1286             $score = !is_null($grade->finalgrade) ? $grade->finalgrade : $grade->rawgrade;
1287
1288             // We are displaying and tracking pass/fail
1289             if ($score >= $item->gradepass) {
1290                 return COMPLETION_COMPLETE_PASS;
1291             } else {
1292                 return COMPLETION_COMPLETE_FAIL;
1293             }
1294         } else {
1295             // Not displaying pass/fail, so just if there is a grade
1296             if (!is_null($grade->finalgrade) || !is_null($grade->rawgrade)) {
1297                 // Grade exists, so maybe complete now
1298                 return COMPLETION_COMPLETE;
1299             } else {
1300                 // Grade does not exist, so maybe incomplete now
1301                 return COMPLETION_INCOMPLETE;
1302             }
1303         }
1304     }
1305
1306     /**
1307      * This is to be used only for system errors (things that shouldn't happen)
1308      * and not user-level errors.
1309      *
1310      * @global object
1311      * @param string $error Error string (will not be displayed to user unless
1312      *   debugging is enabled)
1313      * @return void Throws moodle_exception Exception with the error string as debug info
1314      */
1315     function internal_systemerror($error) {
1316         global $CFG;
1317         throw new moodle_exception('err_system','completion',
1318             $CFG->wwwroot.'/course/view.php?id='.$this->course->id,null,$error);
1319     }
1320
1321     /**
1322      * For testing only. Wipes information cached in user session.
1323      *
1324      * @global object
1325      */
1326     static function wipe_session_cache() {
1327         global $SESSION;
1328         unset($SESSION->completioncache);
1329         unset($SESSION->completioncacheuserid);
1330     }
1331 }