lib/datalib.php

   1 <?php // $Id$
   2 /**
   3  * Library of functions for database manipulation.
   4  *
   5  * Other main libraries:
   6  * - weblib.php - functions that produce web output
   7  * - moodlelib.php - general-purpose Moodle functions
   8  * @author Martin Dougiamas and many others
   9  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
  10  * @package moodlecore
  11  */
  12
  13  /// Some constants
  14  define('LASTACCESS_UPDATE_SECS', 60); /// Number of seconds to wait before
  15                                        /// updating lastaccess information in DB.
  16
  17 /**
  18  * Escape all dangerous characters in a data record
  19  *
  20  * $dataobject is an object containing needed data
  21  * Run over each field exectuting addslashes() function
  22  * to escape SQL unfriendly characters (e.g. quotes)
  23  * Handy when writing back data read from the database
  24  *
  25  * @param $dataobject Object containing the database record
  26  * @return object Same object with neccessary characters escaped
  27  */
  28 function addslashes_object( $dataobject ) {
  29     $a = get_object_vars( $dataobject);
  30     foreach ($a as $key=>$value) {
  31       $a[$key] = addslashes( $value );
  32     }
  33     return (object)$a;
  34 }
  35
  36 /// USER DATABASE ////////////////////////////////////////////////
  37
  38 /**
  39  * Returns $user object of the main admin user
  40  * primary admin = admin with lowest role_assignment id among admins
  41  * @uses $CFG
  42  * @return object(admin) An associative array representing the admin user.
  43  */
  44 function get_admin () {
  45
  46     global $CFG;
  47     static $myadmin;
  48
  49     if (isset($myadmin)) {
  50         return $myadmin;
  51     }
  52
  53     if ( $admins = get_admins() ) {
  54         foreach ($admins as $admin) {
  55             $myadmin = $admin;
  56             return $admin;   // ie the first one
  57         }
  58     } else {
  59         return false;
  60     }
  61 }
  62
  63 /**
  64  * Returns list of all admins, using 1 DB query. It depends on DB schema v1.7
  65  * but does not depend on the v1.9 datastructures (context.path, etc).
  66  *
  67  * @uses $CFG
  68  * @return object
  69  */
  70 function get_admins() {
  71
  72     global $CFG;
  73
  74     $sql = "SELECT ra.userid, SUM(rc.permission) AS permission, MIN(ra.id) AS adminid
  75             FROM " . $CFG->prefix . "role_capabilities rc
  76             JOIN " . $CFG->prefix . "context ctx
  77               ON ctx.id=rc.contextid
  78             JOIN " . $CFG->prefix . "role_assignments ra
  79               ON ra.roleid=rc.roleid AND ra.contextid=ctx.id
  80             WHERE ctx.contextlevel=10
  81               AND rc.capability IN ('moodle/site:config',
  82                                     'moodle/legacy:admin',
  83                                     'moodle/site:doanything')
  84             GROUP BY ra.userid
  85             HAVING SUM(rc.permission) > 0";
  86
  87     $sql = "SELECT u.*, ra.adminid
  88             FROM  " . $CFG->prefix . "user u
  89             JOIN ($sql) ra
  90               ON u.id=ra.userid
  91             ORDER BY ra.adminid ASC";
  92
  93     return get_records_sql($sql);
  94 }
  95
  96
  97 function get_courses_in_metacourse($metacourseid) {
  98     global $CFG;
  99
 100     $sql = "SELECT c.id,c.shortname,c.fullname FROM {$CFG->prefix}course c, {$CFG->prefix}course_meta mc WHERE mc.parent_course = $metacourseid
 101         AND mc.child_course = c.id ORDER BY c.shortname";
 102
 103     return get_records_sql($sql);
 104 }
 105
 106 function get_courses_notin_metacourse($metacourseid,$count=false) {
 107
 108     global $CFG;
 109
 110     if ($count) {
 111         $sql  = "SELECT COUNT(c.id)";
 112     } else {
 113         $sql = "SELECT c.id,c.shortname,c.fullname";
 114     }
 115
 116     $alreadycourses = get_courses_in_metacourse($metacourseid);
 117
 118     $sql .= " FROM {$CFG->prefix}course c WHERE ".((!empty($alreadycourses)) ? "c.id NOT IN (".implode(',',array_keys($alreadycourses)).")
 119     AND " : "")." c.id !=$metacourseid and c.id != ".SITEID." and c.metacourse != 1 ".((empty($count)) ? " ORDER BY c.shortname" : "");
 120
 121     return get_records_sql($sql);
 122 }
 123
 124 function count_courses_notin_metacourse($metacourseid) {
 125     global $CFG;
 126
 127     $alreadycourses = get_courses_in_metacourse($metacourseid);
 128
 129     $sql = "SELECT COUNT(c.id) AS notin FROM {$CFG->prefix}course c
 130              WHERE ".((!empty($alreadycourses)) ? "c.id NOT IN (".implode(',',array_keys($alreadycourses)).")
 131               AND " : "")." c.id !=$metacourseid and c.id != ".SITEID." and c.metacourse != 1";
 132
 133     if (!$count = get_record_sql($sql)) {
 134         return 0;
 135     }
 136
 137     return $count->notin;
 138 }
 139
 140 /**
 141  * Search through course users
 142  *
 143  * If $coursid specifies the site course then this function searches
 144  * through all undeleted and confirmed users
 145  *
 146  * @uses $CFG
 147  * @uses SITEID
 148  * @param int $courseid The course in question.
 149  * @param int $groupid The group in question.
 150  * @param string $searchtext ?
 151  * @param string $sort ?
 152  * @param string $exceptions ?
 153  * @return object
 154  */
 155 function search_users($courseid, $groupid, $searchtext, $sort='', $exceptions='') {
 156     global $CFG;
 157
 158     $LIKE      = sql_ilike();
 159     $fullname  = sql_fullname('u.firstname', 'u.lastname');
 160
 161     if (!empty($exceptions)) {
 162         $except = ' AND u.id NOT IN ('. $exceptions .') ';
 163     } else {
 164         $except = '';
 165     }
 166
 167     if (!empty($sort)) {
 168         $order = ' ORDER BY '. $sort;
 169     } else {
 170         $order = '';
 171     }
 172
 173     $select = 'u.deleted = \'0\' AND u.confirmed = \'1\'';
 174
 175     if (!$courseid or $courseid == SITEID) {
 176         return get_records_sql("SELECT u.id, u.firstname, u.lastname, u.email
 177                       FROM {$CFG->prefix}user u
 178                       WHERE $select
 179                           AND ($fullname $LIKE '%$searchtext%' OR u.email $LIKE '%$searchtext%')
 180                           $except $order");
 181     } else {
 182
 183         if ($groupid) {
 184 //TODO:check. Remove group DB dependencies.
 185             return get_records_sql("SELECT u.id, u.firstname, u.lastname, u.email
 186                           FROM {$CFG->prefix}user u,
 187                                {$CFG->prefix}groups_members gm
 188                           WHERE $select AND gm.groupid = '$groupid' AND gm.userid = u.id
 189                               AND ($fullname $LIKE '%$searchtext%' OR u.email $LIKE '%$searchtext%')
 190                               $except $order");
 191         } else {
 192             $context = get_context_instance(CONTEXT_COURSE, $courseid);
 193             $contextlists = get_related_contexts_string($context);
 194             $users = get_records_sql("SELECT u.id, u.firstname, u.lastname, u.email
 195                           FROM {$CFG->prefix}user u,
 196                                {$CFG->prefix}role_assignments ra
 197                           WHERE $select AND ra.contextid $contextlists AND ra.userid = u.id
 198                               AND ($fullname $LIKE '%$searchtext%' OR u.email $LIKE '%$searchtext%')
 199                               $except $order");
 200         }
 201         return $users;
 202     }
 203 }
 204
 205
 206 /**
 207  * Returns a list of all site users
 208  * Obsolete, just calls get_course_users(SITEID)
 209  *
 210  * @uses SITEID
 211  * @deprecated Use {@link get_course_users()} instead.
 212  * @param string $fields A comma separated list of fields to be returned from the chosen table.
 213  * @return object|false  {@link $USER} records or false if error.
 214  */
 215 function get_site_users($sort='u.lastaccess DESC', $fields='*', $exceptions='') {
 216
 217     return get_course_users(SITEID, $sort, $exceptions, $fields);
 218 }
 219
 220
 221 /**
 222  * Returns a subset of users
 223  *
 224  * @uses $CFG
 225  * @param bool $get If false then only a count of the records is returned
 226  * @param string $search A simple string to search for
 227  * @param bool $confirmed A switch to allow/disallow unconfirmed users
 228  * @param array(int) $exceptions A list of IDs to ignore, eg 2,4,5,8,9,10
 229  * @param string $sort A SQL snippet for the sorting criteria to use
 230  * @param string $firstinitial ?
 231  * @param string $lastinitial ?
 232  * @param string $page ?
 233  * @param string $recordsperpage ?
 234  * @param string $fields A comma separated list of fields to be returned from the chosen table.
 235  * @return object|false|int  {@link $USER} records unless get is false in which case the integer count of the records found is returned. False is returned if an error is encountered.
 236  */
 237 function get_users($get=true, $search='', $confirmed=false, $exceptions='', $sort='firstname ASC',
 238                    $firstinitial='', $lastinitial='', $page='', $recordsperpage='', $fields='*', $extraselect='') {
 239
 240     global $CFG;
 241
 242     if ($get && !$recordsperpage) {
 243         debugging('Call to get_users with $get = true no $recordsperpage limit. ' .
 244                 'On large installations, this will probably cause an out of memory error. ' .
 245                 'Please think again and change your code so that it does not try to ' .
 246                 'load so much data into memory.', DEBUG_DEVELOPER);
 247     }
 248
 249     $LIKE      = sql_ilike();
 250     $fullname  = sql_fullname();
 251
 252     $select = 'username <> \'guest\' AND deleted = 0';
 253
 254     if (!empty($search)){
 255         $search = trim($search);
 256         $select .= " AND ($fullname $LIKE '%$search%' OR email $LIKE '%$search%') ";
 257     }
 258
 259     if ($confirmed) {
 260         $select .= ' AND confirmed = \'1\' ';
 261     }
 262
 263     if ($exceptions) {
 264         $select .= ' AND id NOT IN ('. $exceptions .') ';
 265     }
 266
 267     if ($firstinitial) {
 268         $select .= ' AND firstname '. $LIKE .' \''. $firstinitial .'%\'';
 269     }
 270     if ($lastinitial) {
 271         $select .= ' AND lastname '. $LIKE .' \''. $lastinitial .'%\'';
 272     }
 273
 274     if ($extraselect) {
 275         $select .= " AND $extraselect ";
 276     }
 277
 278     if ($get) {
 279         return get_records_select('user', $select, $sort, $fields, $page, $recordsperpage);
 280     } else {
 281         return count_records_select('user', $select);
 282     }
 283 }
 284
 285
 286 /**
 287  * shortdesc (optional)
 288  *
 289  * longdesc
 290  *
 291  * @uses $CFG
 292  * @param string $sort ?
 293  * @param string $dir ?
 294  * @param int $categoryid ?
 295  * @param int $categoryid ?
 296  * @param string $search ?
 297  * @param string $firstinitial ?
 298  * @param string $lastinitial ?
 299  * @returnobject {@link $USER} records
 300  * @todo Finish documenting this function
 301  */
 302
 303 function get_users_listing($sort='lastaccess', $dir='ASC', $page=0, $recordsperpage=0,
 304                            $search='', $firstinitial='', $lastinitial='', $extraselect='') {
 305
 306     global $CFG;
 307
 308     $LIKE      = sql_ilike();
 309     $fullname  = sql_fullname();
 310
 311     $select = "deleted <> '1'";
 312
 313     if (!empty($search)) {
 314         $search = trim($search);
 315         $select .= " AND ($fullname $LIKE '%$search%' OR email $LIKE '%$search%' OR username='$search') ";
 316     }
 317
 318     if ($firstinitial) {
 319         $select .= ' AND firstname '. $LIKE .' \''. $firstinitial .'%\' ';
 320     }
 321
 322     if ($lastinitial) {
 323         $select .= ' AND lastname '. $LIKE .' \''. $lastinitial .'%\' ';
 324     }
 325
 326     if ($extraselect) {
 327         $select .= " AND $extraselect ";
 328     }
 329
 330     if ($sort) {
 331         $sort = ' ORDER BY '. $sort .' '. $dir;
 332     }
 333
 334 /// warning: will return UNCONFIRMED USERS
 335     return get_records_sql("SELECT id, username, email, firstname, lastname, city, country, lastaccess, confirmed, mnethostid
 336                               FROM {$CFG->prefix}user
 337                              WHERE $select $sort", $page, $recordsperpage);
 338
 339 }
 340
 341
 342 /**
 343  * Full list of users that have confirmed their accounts.
 344  *
 345  * @uses $CFG
 346  * @return object
 347  */
 348 function get_users_confirmed() {
 349     global $CFG;
 350     return get_records_sql("SELECT *
 351                               FROM {$CFG->prefix}user
 352                              WHERE confirmed = 1
 353                                AND deleted = 0
 354                                AND username <> 'guest'");
 355 }
 356
 357
 358 /// OTHER SITE AND COURSE FUNCTIONS /////////////////////////////////////////////
 359
 360
 361 /**
 362  * Returns $course object of the top-level site.
 363  *
 364  * @return course  A {@link $COURSE} object for the site
 365  */
 366 function get_site() {
 367
 368     global $SITE;
 369
 370     if (!empty($SITE->id)) {   // We already have a global to use, so return that
 371         return $SITE;
 372     }
 373
 374     if ($course = get_record('course', 'category', 0)) {
 375         return $course;
 376     } else {
 377         return false;
 378     }
 379 }
 380
 381 /**
 382  * Returns list of courses, for whole site, or category
 383  *
 384  * Returns list of courses, for whole site, or category
 385  * Important: Using c.* for fields is extremely expensive because
 386  *            we are using distinct. You almost _NEVER_ need all the fields
 387  *            in such a large SELECT
 388  *
 389  * @param    type description
 390  *
 391  */
 392 function get_courses($categoryid="all", $sort="c.sortorder ASC", $fields="c.*") {
 393
 394     global $USER, $CFG;
 395
 396     if ($categoryid != "all" && is_numeric($categoryid)) {
 397         $categoryselect = "WHERE c.category = '$categoryid'";
 398     } else {
 399         $categoryselect = "";
 400     }
 401
 402     if (empty($sort)) {
 403         $sortstatement = "";
 404     } else {
 405         $sortstatement = "ORDER BY $sort";
 406     }
 407
 408     $visiblecourses = array();
 409
 410     // pull out all course matching the cat
 411     if ($courses = get_records_sql("SELECT $fields,
 412                                     ctx.id AS ctxid, ctx.path AS ctxpath,
 413                                     ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
 414                                     FROM {$CFG->prefix}course c
 415                                     JOIN {$CFG->prefix}context ctx
 416                                       ON (c.id = ctx.instanceid
 417                                           AND ctx.contextlevel=".CONTEXT_COURSE.")
 418                                     $categoryselect
 419                                     $sortstatement")) {
 420
 421         // loop throught them
 422         foreach ($courses as $course) {
 423             $course = make_context_subobj($course);
 424             if (isset($course->visible) && $course->visible <= 0) {
 425                 // for hidden courses, require visibility check
 426                 if (has_capability('moodle/course:viewhiddencourses', $course->context)) {
 427                     $visiblecourses [] = $course;
 428                 }
 429             } else {
 430                 $visiblecourses [] = $course;
 431             }
 432         }
 433     }
 434     return $visiblecourses;
 435
 436 /*
 437     $teachertable = "";
 438     $visiblecourses = "";
 439     $sqland = "";
 440     if (!empty($categoryselect)) {
 441         $sqland = "AND ";
 442     }
 443     if (!empty($USER->id)) {  // May need to check they are a teacher
 444         if (!has_capability('moodle/course:create', get_context_instance(CONTEXT_SYSTEM))) {
 445             $visiblecourses = "$sqland ((c.visible > 0) OR t.userid = '$USER->id')";
 446             $teachertable = "LEFT JOIN {$CFG->prefix}user_teachers t ON t.course = c.id";
 447         }
 448     } else {
 449         $visiblecourses = "$sqland c.visible > 0";
 450     }
 451
 452     if ($categoryselect or $visiblecourses) {
 453         $selectsql = "{$CFG->prefix}course c $teachertable WHERE $categoryselect $visiblecourses";
 454     } else {
 455         $selectsql = "{$CFG->prefix}course c $teachertable";
 456     }
 457
 458     $extrafield = str_replace('ASC','',$sort);
 459     $extrafield = str_replace('DESC','',$extrafield);
 460     $extrafield = trim($extrafield);
 461     if (!empty($extrafield)) {
 462         $extrafield = ','.$extrafield;
 463     }
 464     return get_records_sql("SELECT ".((!empty($teachertable)) ? " DISTINCT " : "")." $fields $extrafield FROM $selectsql ".((!empty($sort)) ? "ORDER BY $sort" : ""));
 465     */
 466 }
 467
 468
 469 /**
 470  * Returns list of courses, for whole site, or category
 471  *
 472  * Similar to get_courses, but allows paging
 473  * Important: Using c.* for fields is extremely expensive because
 474  *            we are using distinct. You almost _NEVER_ need all the fields
 475  *            in such a large SELECT
 476  *
 477  * @param    type description
 478  *
 479  */
 480 function get_courses_page($categoryid="all", $sort="c.sortorder ASC", $fields="c.*",
 481                           &$totalcount, $limitfrom="", $limitnum="") {
 482
 483     global $USER, $CFG;
 484
 485     $categoryselect = "";
 486     if ($categoryid != "all" && is_numeric($categoryid)) {
 487         $categoryselect = "WHERE c.category = '$categoryid'";
 488     } else {
 489         $categoryselect = "";
 490     }
 491
 492     // pull out all course matching the cat
 493     $visiblecourses = array();
 494     if (!($rs = get_recordset_sql("SELECT $fields,
 495                                           ctx.id AS ctxid, ctx.path AS ctxpath,
 496                                           ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
 497                                    FROM {$CFG->prefix}course c
 498                                    JOIN {$CFG->prefix}context ctx
 499                                      ON (c.id = ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
 500                                    $categoryselect
 501                                    ORDER BY $sort"))) {
 502         return $visiblecourses;
 503     }
 504     $totalcount = 0;
 505
 506     if (!$limitfrom) {
 507         $limitfrom = 0;
 508     }
 509
 510     // iteration will have to be done inside loop to keep track of the limitfrom and limitnum
 511     while ($course = rs_fetch_next_record($rs)) {
 512         $course = make_context_subobj($course);
 513         if ($course->visible <= 0) {
 514             // for hidden courses, require visibility check
 515             if (has_capability('moodle/course:viewhiddencourses', $course->context)) {
 516                 $totalcount++;
 517                 if ($totalcount > $limitfrom && (!$limitnum or count($visiblecourses) < $limitnum)) {
 518                     $visiblecourses [] = $course;
 519                 }
 520             }
 521         } else {
 522             $totalcount++;
 523             if ($totalcount > $limitfrom && (!$limitnum or count($visiblecourses) < $limitnum)) {
 524                 $visiblecourses [] = $course;
 525             }
 526         }
 527     }
 528     rs_close($rs);
 529     return $visiblecourses;
 530
 531 /**
 532
 533     $categoryselect = "";
 534     if ($categoryid != "all" && is_numeric($categoryid)) {
 535         $categoryselect = "c.category = '$categoryid'";
 536     }
 537
 538     $teachertable = "";
 539     $visiblecourses = "";
 540     $sqland = "";
 541     if (!empty($categoryselect)) {
 542         $sqland = "AND ";
 543     }
 544     if (!empty($USER) and !empty($USER->id)) {  // May need to check they are a teacher
 545         if (!has_capability('moodle/course:create', get_context_instance(CONTEXT_SYSTEM))) {
 546             $visiblecourses = "$sqland ((c.visible > 0) OR t.userid = '$USER->id')";
 547             $teachertable = "LEFT JOIN {$CFG->prefix}user_teachers t ON t.course=c.id";
 548         }
 549     } else {
 550         $visiblecourses = "$sqland c.visible > 0";
 551     }
 552
 553     if ($limitfrom !== "") {
 554         $limit = sql_paging_limit($limitfrom, $limitnum);
 555     } else {
 556         $limit = "";
 557     }
 558
 559     $selectsql = "{$CFG->prefix}course c $teachertable WHERE $categoryselect $visiblecourses";
 560
 561     $totalcount = count_records_sql("SELECT COUNT(DISTINCT c.id) FROM $selectsql");
 562
 563     return get_records_sql("SELECT $fields FROM $selectsql ".((!empty($sort)) ? "ORDER BY $sort" : "")." $limit");
 564     */
 565 }
 566
 567 /*
 568  * Retrieve course records with the course managers and other related records
 569  * that we need for print_course(). This allows print_courses() to do its job
 570  * in a constant number of DB queries, regardless of the number of courses,
 571  * role assignments, etc.
 572  *
 573  * The returned array is indexed on c.id, and each course will have
 574  * - $course->context - a context obj
 575  * - $course->managers - array containing RA objects that include a $user obj
 576  *                       with the minimal fields needed for fullname()
 577  *
 578  */
 579 function get_courses_wmanagers($categoryid=0, $sort="c.sortorder ASC", $fields=array()) {
 580     /*
 581      * The plan is to
 582      *
 583      * - Grab the courses JOINed w/context
 584      *
 585      * - Grab the interesting course-manager RAs
 586      *   JOINed with a base user obj and add them to each course
 587      *
 588      * So as to do all the work in 2 DB queries. The RA+user JOIN
 589      * ends up being pretty expensive if it happens over _all_
 590      * courses on a large site. (Are we surprised!?)
 591      *
 592      * So this should _never_ get called with 'all' on a large site.
 593      *
 594      */
 595     global $USER, $CFG;
 596
 597     $allcats = false; // bool flag
 598     if ($categoryid === 'all') {
 599         $categoryclause   = '';
 600         $allcats = true;
 601     } elseif (is_numeric($categoryid)) {
 602         $categoryclause = "c.category = $categoryid";
 603     } else {
 604         debugging("Could not recognise categoryid = $categoryid");
 605         $categoryclause = '';
 606     }
 607
 608     $basefields = array('id', 'category', 'sortorder',
 609                         'shortname', 'fullname', 'idnumber',
 610                         'teacher', 'teachers', 'student', 'students',
 611                         'guest', 'startdate', 'visible',
 612                         'newsitems',  'cost', 'enrol',
 613                         'groupmode', 'groupmodeforce');
 614
 615     if (!is_null($fields) && is_string($fields)) {
 616         if (empty($fields)) {
 617             $fields = $basefields;
 618         } else {
 619             // turn the fields from a string to an array that
 620             // get_user_courses_bycap() will like...
 621             $fields = explode(',',$fields);
 622             $fields = array_map('trim', $fields);
 623             $fields = array_unique(array_merge($basefields, $fields));
 624         }
 625     } elseif (is_array($fields)) {
 626         $fields = array_merge($basefields,$fields);
 627     }
 628     $coursefields = 'c.' .join(',c.', $fields);
 629
 630     if (empty($sort)) {
 631         $sortstatement = "";
 632     } else {
 633         $sortstatement = "ORDER BY $sort";
 634     }
 635
 636     $where = 'WHERE c.id != ' . SITEID;
 637     if ($categoryclause !== ''){
 638         $where = "$where AND $categoryclause";
 639     }
 640
 641     // pull out all courses matching the cat
 642     $sql = "SELECT $coursefields,
 643                    ctx.id AS ctxid, ctx.path AS ctxpath,
 644                    ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
 645             FROM {$CFG->prefix}course c
 646             JOIN {$CFG->prefix}context ctx
 647                  ON (c.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
 648                  $where
 649                  $sortstatement";
 650
 651     $catpaths = array();
 652     $catpath  = NULL;
 653     if ($courses = get_records_sql($sql)) {
 654         // loop on courses materialising
 655         // the context, and prepping data to fetch the
 656         // managers efficiently later...
 657         foreach ($courses as $k => $course) {
 658             $courses[$k] = make_context_subobj($courses[$k]);
 659             $courses[$k]->managers = array();
 660             if ($allcats === false) {
 661                 // single cat, so take just the first one...
 662                 if ($catpath === NULL) {
 663                     $catpath = preg_replace(':/\d+$:', '',$courses[$k]->context->path);
 664                 }
 665             } else {
 666                 // chop off the contextid of the course itself
 667                 // like dirname() does...
 668                 $catpaths[] = preg_replace(':/\d+$:', '',$courses[$k]->context->path);
 669             }
 670         }
 671     } else {
 672         return array(); // no courses!
 673     }
 674
 675     $CFG->coursemanager = trim($CFG->coursemanager);
 676     if (empty($CFG->coursemanager)) {
 677         return $courses;
 678     }
 679
 680     $managerroles = split(',', $CFG->coursemanager);
 681     $catctxids = '';
 682     if (count($managerroles)) {
 683         if ($allcats === true) {
 684             $catpaths  = array_unique($catpaths);
 685             $ctxids = array();
 686             foreach ($catpaths as $cpath) {
 687                 $ctxids = array_merge($ctxids, explode('/',substr($cpath,1)));
 688             }
 689             $ctxids = array_unique($ctxids);
 690             $catctxids = implode( ',' , $ctxids);
 691             unset($catpaths);
 692             unset($cpath);
 693         } else {
 694             // take the ctx path from the first course
 695             // as all categories will be the same...
 696             $catpath = substr($catpath,1);
 697             $catpath = preg_replace(':/\d+$:','',$catpath);
 698             $catctxids = str_replace('/',',',$catpath);
 699         }
 700         if ($categoryclause !== '') {
 701             $categoryclause = "AND $categoryclause";
 702         }
 703         /*
 704          * Note: Here we use a LEFT OUTER JOIN that can
 705          * "optionally" match to avoid passing a ton of context
 706          * ids in an IN() clause. Perhaps a subselect is faster.
 707          *
 708          * In any case, this SQL is not-so-nice over large sets of
 709          * courses with no $categoryclause.
 710          *
 711          */
 712         $sql = "SELECT ctx.path, ctx.instanceid, ctx.contextlevel,
 713                        ra.hidden,
 714                        r.id AS roleid, r.name as rolename,
 715                        u.id AS userid, u.firstname, u.lastname
 716                 FROM {$CFG->prefix}role_assignments ra
 717                 JOIN {$CFG->prefix}context ctx
 718                   ON ra.contextid = ctx.id
 719                 JOIN {$CFG->prefix}user u
 720                   ON ra.userid = u.id
 721                 JOIN {$CFG->prefix}role r
 722                   ON ra.roleid = r.id
 723                 LEFT OUTER JOIN {$CFG->prefix}course c
 724                   ON (ctx.instanceid=c.id AND ctx.contextlevel=".CONTEXT_COURSE.")
 725                 WHERE ( c.id IS NOT NULL";
 726         // under certain conditions, $catctxids is NULL
 727         if($catctxids == NULL){
 728             $sql .= ") ";
 729         }else{
 730             $sql .= " OR ra.contextid  IN ($catctxids) )";
 731         }
 732
 733         $sql .= "AND ra.roleid IN ({$CFG->coursemanager})
 734                       $categoryclause
 735                 ORDER BY r.sortorder ASC, ctx.contextlevel ASC, ra.sortorder ASC";
 736         $rs = get_recordset_sql($sql);
 737
 738         // This loop is fairly stupid as it stands - might get better
 739         // results doing an initial pass clustering RAs by path.
 740         while ($ra = rs_fetch_next_record($rs)) {
 741             $user = new StdClass;
 742             $user->id        = $ra->userid;    unset($ra->userid);
 743             $user->firstname = $ra->firstname; unset($ra->firstname);
 744             $user->lastname  = $ra->lastname;  unset($ra->lastname);
 745             $ra->user = $user;
 746             if ($ra->contextlevel == CONTEXT_SYSTEM) {
 747                 foreach ($courses as $k => $course) {
 748                     $courses[$k]->managers[] = $ra;
 749                 }
 750             } elseif ($ra->contextlevel == CONTEXT_COURSECAT) {
 751                 if ($allcats === false) {
 752                     // It always applies
 753                     foreach ($courses as $k => $course) {
 754                         $courses[$k]->managers[] = $ra;
 755                     }
 756                 } else {
 757                     foreach ($courses as $k => $course) {
 758                         // Note that strpos() returns 0 as "matched at pos 0"
 759                         if (strpos($course->context->path, $ra->path.'/')===0) {
 760                             // Only add it to subpaths
 761                             $courses[$k]->managers[] = $ra;
 762                         }
 763                     }
 764                 }
 765             } else { // course-level
 766                 if(!array_key_exists($ra->instanceid, $courses)) {
 767                     //this course is not in a list, probably a frontpage course
 768                     continue;
 769                 }
 770                 $courses[$ra->instanceid]->managers[] = $ra;
 771             }
 772         }
 773         rs_close($rs);
 774     }
 775
 776     return $courses;
 777 }
 778
 779 /**
 780  * Convenience function - lists courses that a user has access to view.
 781  *
 782  * For admins and others with access to "every" course in the system, we should
 783  * try to get courses with explicit RAs.
 784  *
 785  * NOTE: this function is heavily geared towards the perspective of the user
 786  *       passed in $userid. So it will hide courses that the user cannot see
 787  *       (for any reason) even if called from cron or from another $USER's
 788  *       perspective.
 789  *
 790  *       If you really want to know what courses are assigned to the user,
 791  *       without any hiding or scheming, call the lower-level
 792  *       get_user_courses_bycap().
 793  *
 794  *
 795  * Notes inherited from get_user_courses_bycap():
 796  *
 797  * - $fields is an array of fieldnames to ADD
 798  *   so name the fields you really need, which will
 799  *   be added and uniq'd
 800  *
 801  * - the course records have $c->context which is a fully
 802  *   valid context object. Saves you a query per course!
 803  *
 804  * @uses $CFG,$USER
 805  * @param int $userid The user of interest
 806  * @param string $sort the sortorder in the course table
 807  * @param array $fields - names of _additional_ fields to return (also accepts a string)
 808  * @param bool $doanything True if using the doanything flag
 809  * @param int $limit Maximum number of records to return, or 0 for unlimited
 810  * @return array {@link $COURSE} of course objects
 811  */
 812 function get_my_courses($userid, $sort='visible DESC,sortorder ASC', $fields=NULL, $doanything=false,$limit=0) {
 813
 814     global $CFG,$USER;
 815
 816     // Guest's do not have any courses
 817     $sitecontext = get_context_instance(CONTEXT_SYSTEM);
 818     if (has_capability('moodle/legacy:guest',$sitecontext,$userid,false)) {
 819         return(array());
 820     }
 821
 822     $basefields = array('id', 'category', 'sortorder',
 823                         'shortname', 'fullname', 'idnumber',
 824                         'teacher', 'teachers', 'student', 'students',
 825                         'guest', 'startdate', 'visible',
 826                         'newsitems',  'cost', 'enrol',
 827                         'groupmode', 'groupmodeforce');
 828
 829     if (!is_null($fields) && is_string($fields)) {
 830         if (empty($fields)) {
 831             $fields = $basefields;
 832         } else {
 833             // turn the fields from a string to an array that
 834             // get_user_courses_bycap() will like...
 835             $fields = explode(',',$fields);
 836             $fields = array_map('trim', $fields);
 837             $fields = array_unique(array_merge($basefields, $fields));
 838         }
 839     } elseif (is_array($fields)) {
 840         $fields = array_unique(array_merge($basefields, $fields));
 841     } else {
 842         $fields = $basefields;
 843     }
 844
 845     $orderby = '';
 846     $sort    = trim($sort);
 847     if (!empty($sort)) {
 848         $rawsorts = explode(',', $sort);
 849         $sorts = array();
 850         foreach ($rawsorts as $rawsort) {
 851             $rawsort = trim($rawsort);
 852             if (strpos($rawsort, 'c.') === 0) {
 853                 $rawsort = substr($rawsort, 2);
 854             }
 855             $sorts[] = trim($rawsort);
 856         }
 857         $sort = 'c.'.implode(',c.', $sorts);
 858         $orderby = "ORDER BY $sort";
 859     }
 860
 861     //
 862     // Logged-in user - Check cached courses
 863     //
 864     // NOTE! it's a _string_ because
 865     // - it's all we'll ever use
 866     // - it serialises much more compact than an array
 867     //   this a big concern here - cost of serialise
 868     //   and unserialise gets huge as the session grows
 869     //
 870     // If the courses are too many - it won't be set
 871     // for large numbers of courses, caching in the session
 872     // has marginal benefits (costs too much, not
 873     // worthwhile...) and we may hit SQL parser limits
 874     // because we use IN()
 875     //
 876     if ($userid === $USER->id) {
 877         if (isset($USER->loginascontext)
 878             && $USER->loginascontext->contextlevel == CONTEXT_COURSE) {
 879             // list _only_ this course
 880             // anything else is asking for trouble...
 881             $courseids = $USER->loginascontext->instanceid;
 882         } elseif (isset($USER->mycourses)
 883                   && is_string($USER->mycourses)) {
 884             if ($USER->mycourses === '') {
 885                 // empty str means: user has no courses
 886                 // ... so do the easy thing...
 887                 return array();
 888             } else {
 889                 $courseids = $USER->mycourses;
 890             }
 891         }
 892         if (isset($courseids)) {
 893             // The data massaging here MUST be kept in sync with
 894             // get_user_courses_bycap() so we return
 895             // the same...
 896             // (but here we don't need to check has_cap)
 897             $coursefields = 'c.' .join(',c.', $fields);
 898             $sql = "SELECT $coursefields,
 899                            ctx.id AS ctxid, ctx.path AS ctxpath,
 900                            ctx.depth as ctxdepth, ctx.contextlevel AS ctxlevel,
 901                            cc.path AS categorypath
 902                     FROM {$CFG->prefix}course c
 903                     JOIN {$CFG->prefix}course_categories cc
 904                       ON c.category=cc.id
 905                     JOIN {$CFG->prefix}context ctx
 906                       ON (c.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
 907                     WHERE c.id IN ($courseids)
 908                     $orderby";
 909             $rs = get_recordset_sql($sql);
 910             $courses = array();
 911             $cc = 0; // keep count
 912             while ($c = rs_fetch_next_record($rs)) {
 913                 // build the context obj
 914                 $c = make_context_subobj($c);
 915
 916                 $courses[$c->id] = $c;
 917                 if ($limit > 0 && $cc++ > $limit) {
 918                     break;
 919                 }
 920             }
 921             rs_close($rs);
 922             return $courses;
 923         }
 924     }
 925
 926     // Non-cached - get accessinfo
 927     if ($userid === $USER->id && isset($USER->access)) {
 928         $accessinfo = $USER->access;
 929     } else {
 930         $accessinfo = get_user_access_sitewide($userid);
 931     }
 932
 933
 934     $courses = get_user_courses_bycap($userid, 'moodle/course:view', $accessinfo,
 935                                       $doanything, $sort, $fields,
 936                                       $limit);
 937
 938     $cats = NULL;
 939     // If we have to walk category visibility
 940     // to eval course visibility, get the categories
 941     if (empty($CFG->allowvisiblecoursesinhiddencategories)) {
 942         $sql = "SELECT cc.id, cc.path, cc.visible,
 943                        ctx.id AS ctxid, ctx.path AS ctxpath,
 944                        ctx.depth as ctxdepth, ctx.contextlevel AS ctxlevel
 945                  FROM {$CFG->prefix}course_categories cc
 946                  JOIN {$CFG->prefix}context ctx ON (cc.id = ctx.instanceid)
 947                 WHERE ctx.contextlevel = ".CONTEXT_COURSECAT."
 948              ORDER BY cc.id";
 949         $rs = get_recordset_sql($sql);
 950
 951         // Using a temporary array instead of $cats here, to avoid a "true" result when isnull($cats) further down
 952         $categories = array();
 953         while ($course_cat = rs_fetch_next_record($rs)) {
 954             // build the context obj
 955             $course_cat = make_context_subobj($course_cat);
 956             $categories[$course_cat->id] = $course_cat;
 957         }
 958         rs_close($rs);
 959
 960         if (!empty($categories)) {
 961             $cats = $categories;
 962         }
 963
 964         unset($course_cat);
 965     }
 966     //
 967     // Strangely, get_my_courses() is expected to return the
 968     // array keyed on id, which messes up the sorting
 969     // So do that, and also cache the ids in the session if appropriate
 970     //
 971     $kcourses = array();
 972     $courses_count = count($courses);
 973     $cacheids = NULL;
 974     $vcatpaths = array();
 975     if ($userid === $USER->id && $courses_count < 500) {
 976         $cacheids = array();
 977     }
 978     for ($n=0; $n<$courses_count; $n++) {
 979
 980         //
 981         // Check whether $USER (not $userid) can _actually_ see them
 982         // Easy if $CFG->allowvisiblecoursesinhiddencategories
 983         // is set, and we don't have to care about categories.
 984         // Lots of work otherwise... (all in mem though!)
 985         //
 986         $cansee = false;
 987         if (is_null($cats)) { // easy rules!
 988             if ($courses[$n]->visible == true) {
 989                 $cansee = true;
 990             } elseif (has_capability('moodle/course:viewhiddencourses',
 991                                      $courses[$n]->context, $USER->id)) {
 992                 $cansee = true;
 993             }
 994         } else {
 995             //
 996             // Is the cat visible?
 997             // we have to assume it _is_ visible
 998             // so we can shortcut when we find a hidden one
 999             //
1000             $viscat = true;
1001             $cpath = $courses[$n]->categorypath;
1002             if (isset($vcatpaths[$cpath])) {
1003                 $viscat = $vcatpaths[$cpath];
1004             } else {
1005                 $cpath = substr($cpath,1); // kill leading slash
1006                 $cpath = explode('/',$cpath);
1007                 $ccct  = count($cpath);
1008                 for ($m=0;$m<$ccct;$m++) {
1009                     $ccid = $cpath[$m];
1010                     if ($cats[$ccid]->visible==false) {
1011                         $viscat = false;
1012                         break;
1013                     }
1014                 }
1015                 $vcatpaths[$courses[$n]->categorypath] = $viscat;
1016             }
1017
1018             //
1019             // Perhaps it's actually visible to $USER
1020             // check moodle/category:visibility
1021             //
1022             // The name isn't obvious, but the description says
1023             // "See hidden categories" so the user shall see...
1024             // But also check if the allowvisiblecoursesinhiddencategories setting is true, and check for course visibility
1025             if ($viscat === false) {
1026                 $catctx = $cats[$courses[$n]->category]->context;
1027                 if (has_capability('moodle/category:visibility', $catctx, $USER->id)) {
1028                     $vcatpaths[$courses[$n]->categorypath] = true;
1029                     $viscat = true;
1030                 } elseif ($CFG->allowvisiblecoursesinhiddencategories && $courses[$n]->visible == true) {
1031                     $viscat = true;
1032                 }
1033             }
1034
1035             //
1036             // Decision matrix
1037             //
1038             if ($viscat === true) {
1039                 if ($courses[$n]->visible == true) {
1040                     $cansee = true;
1041                 } elseif (has_capability('moodle/course:viewhiddencourses',
1042                                         $courses[$n]->context, $USER->id)) {
1043                     $cansee = true;
1044                 }
1045             }
1046         }
1047         if ($cansee === true) {
1048             $kcourses[$courses[$n]->id] = $courses[$n];
1049             if (is_array($cacheids)) {
1050                 $cacheids[] = $courses[$n]->id;
1051             }
1052         }
1053     }
1054     if (is_array($cacheids)) {
1055         // Only happens
1056         // - for the logged in user
1057         // - below the threshold (500)
1058         // empty string is _valid_
1059         $USER->mycourses = join(',',$cacheids);
1060     } elseif ($userid === $USER->id && isset($USER->mycourses)) {
1061         // cheap sanity check
1062         unset($USER->mycourses);
1063     }
1064
1065     return $kcourses;
1066 }
1067
1068 /**
1069  * A list of courses that match a search
1070  *
1071  * @uses $CFG
1072  * @param array $searchterms ?
1073  * @param string $sort ?
1074  * @param int $page ?
1075  * @param int $recordsperpage ?
1076  * @param int $totalcount Passed in by reference. ?
1077  * @return object {@link $COURSE} records
1078  */
1079 function get_courses_search($searchterms, $sort='fullname ASC', $page=0, $recordsperpage=50, &$totalcount) {
1080
1081     global $CFG;
1082
1083     //to allow case-insensitive search for postgesql
1084     if ($CFG->dbfamily == 'postgres') {
1085         $LIKE = 'ILIKE';
1086         $NOTLIKE = 'NOT ILIKE';   // case-insensitive
1087         $REGEXP = '~*';
1088         $NOTREGEXP = '!~*';
1089     } else {
1090         $LIKE = 'LIKE';
1091         $NOTLIKE = 'NOT LIKE';
1092         $REGEXP = 'REGEXP';
1093         $NOTREGEXP = 'NOT REGEXP';
1094     }
1095
1096     $fullnamesearch = '';
1097     $summarysearch = '';
1098
1099     foreach ($searchterms as $searchterm) {
1100
1101         $NOT = ''; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
1102                    /// will use it to simulate the "-" operator with LIKE clause
1103
1104     /// Under Oracle and MSSQL, trim the + and - operators and perform
1105     /// simpler LIKE (or NOT LIKE) queries
1106         if ($CFG->dbfamily == 'oracle' || $CFG->dbfamily == 'mssql') {
1107             if (substr($searchterm, 0, 1) == '-') {
1108                 $NOT = ' NOT ';
1109             }
1110             $searchterm = trim($searchterm, '+-');
1111         }
1112
1113         if ($fullnamesearch) {
1114             $fullnamesearch .= ' AND ';
1115         }
1116         if ($summarysearch) {
1117             $summarysearch .= ' AND ';
1118         }
1119
1120         if (substr($searchterm,0,1) == '+') {
1121             $searchterm      = substr($searchterm,1);
1122             $summarysearch  .= " c.summary $REGEXP '(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)' ";
1123             $fullnamesearch .= " c.fullname $REGEXP '(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)' ";
1124         } else if (substr($searchterm,0,1) == "-") {
1125             $searchterm      = substr($searchterm,1);
1126             $summarysearch  .= " c.summary $NOTREGEXP '(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)' ";
1127             $fullnamesearch .= " c.fullname $NOTREGEXP '(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)' ";
1128         } else {
1129             $summarysearch .= ' summary '. $NOT . $LIKE .' \'%'. $searchterm .'%\' ';
1130             $fullnamesearch .= ' fullname '. $NOT . $LIKE .' \'%'. $searchterm .'%\' ';
1131         }
1132
1133     }
1134
1135     $sql = "SELECT c.*,
1136                    ctx.id AS ctxid, ctx.path AS ctxpath,
1137                    ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
1138             FROM {$CFG->prefix}course c
1139             JOIN {$CFG->prefix}context ctx
1140              ON (c.id = ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
1141             WHERE (( $fullnamesearch ) OR ( $summarysearch ))
1142                   AND category > 0
1143             ORDER BY " . $sort;
1144
1145     $courses = array();
1146
1147     if ($rs = get_recordset_sql($sql)) {
1148
1149
1150         // Tiki pagination
1151         $limitfrom = $page * $recordsperpage;
1152         $limitto   = $limitfrom + $recordsperpage;
1153         $c = 0; // counts how many visible courses we've seen
1154
1155         while ($course = rs_fetch_next_record($rs)) {
1156             $course = make_context_subobj($course);
1157             if ($course->visible || has_capability('moodle/course:viewhiddencourses', $course->context)) {
1158                 // Don't exit this loop till the end
1159                 // we need to count all the visible courses
1160                 // to update $totalcount
1161                 if ($c >= $limitfrom && $c < $limitto) {
1162                     $courses[] = $course;
1163                 }
1164                 $c++;
1165             }
1166         }
1167     }
1168
1169     // our caller expects 2 bits of data - our return
1170     // array, and an updated $totalcount
1171     $totalcount = $c;
1172     return $courses;
1173 }
1174
1175
1176 /**
1177  * Returns a sorted list of categories. Each category object has a context
1178  * property that is a context object.
1179  *
1180  * When asking for $parent='none' it will return all the categories, regardless
1181  * of depth. Wheen asking for a specific parent, the default is to return
1182  * a "shallow" resultset. Pass false to $shallow and it will return all
1183  * the child categories as well.
1184  *
1185  *
1186  * @param string $parent The parent category if any
1187  * @param string $sort the sortorder
1188  * @param bool   $shallow - set to false to get the children too
1189  * @return array of categories
1190  */
1191 function get_categories($parent='none', $sort=NULL, $shallow=true) {
1192     global $CFG;
1193
1194     if ($sort === NULL) {
1195         $sort = 'ORDER BY cc.sortorder ASC';
1196     } elseif ($sort ==='') {
1197         // leave it as empty
1198     } else {
1199         $sort = "ORDER BY $sort";
1200     }
1201
1202     if ($parent === 'none') {
1203         $sql = "SELECT cc.*,
1204                       ctx.id AS ctxid, ctx.path AS ctxpath,
1205                       ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
1206                 FROM {$CFG->prefix}course_categories cc
1207                 JOIN {$CFG->prefix}context ctx
1208                   ON cc.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT."
1209                 $sort";
1210     } elseif ($shallow) {
1211         $parent = (int)$parent;
1212         $sql = "SELECT cc.*,
1213                        ctx.id AS ctxid, ctx.path AS ctxpath,
1214                        ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
1215                 FROM {$CFG->prefix}course_categories cc
1216                 JOIN {$CFG->prefix}context ctx
1217                   ON cc.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT."
1218                 WHERE cc.parent=$parent
1219                 $sort";
1220     } else {
1221         $parent = (int)$parent;
1222         $sql = "SELECT cc.*,
1223                        ctx.id AS ctxid, ctx.path AS ctxpath,
1224                        ctx.depth AS ctxdepth, ctx.contextlevel AS ctxlevel
1225                 FROM {$CFG->prefix}course_categories cc
1226                 JOIN {$CFG->prefix}context ctx
1227                   ON cc.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT."
1228                 JOIN {$CFG->prefix}course_categories ccp
1229                      ON (cc.path LIKE ".sql_concat('ccp.path',"'%'").")
1230                 WHERE ccp.id=$parent
1231                 $sort";
1232     }
1233     $categories = array();
1234
1235     if( $rs = get_recordset_sql($sql) ){
1236         while ($cat = rs_fetch_next_record($rs)) {
1237             $cat = make_context_subobj($cat);
1238             if ($cat->visible || has_capability('moodle/category:visibility',$cat->context)) {
1239                 $categories[$cat->id] = $cat;
1240             }
1241         }
1242     }
1243     return $categories;
1244 }
1245
1246
1247 /**
1248  * Returns an array of category ids of all the subcategories for a given
1249  * category.
1250  * @param $catid - The id of the category whose subcategories we want to find.
1251  * @return array of category ids.
1252  */
1253 function get_all_subcategories($catid) {
1254
1255     $subcats = array();
1256
1257     if ($categories = get_records('course_categories', 'parent', $catid)) {
1258         foreach ($categories as $cat) {
1259             array_push($subcats, $cat->id);
1260             $subcats = array_merge($subcats, get_all_subcategories($cat->id));
1261         }
1262     }
1263     return $subcats;
1264 }
1265
1266
1267 /**
1268 * This recursive function makes sure that the courseorder is consecutive
1269 *
1270 * @param    type description
1271 *
1272 * $n is the starting point, offered only for compatilibity -- will be ignored!
1273 * $safe (bool) prevents it from assuming category-sortorder is unique, used to upgrade
1274 *       safely from 1.4 to 1.5
1275 */
1276 function fix_course_sortorder($categoryid=0, $n=0, $safe=0, $depth=0, $path='') {
1277
1278     global $CFG;
1279
1280     $count = 0;
1281
1282     $catgap    = 1000; // "standard" category gap
1283     $tolerance = 200;  // how "close" categories can get
1284
1285     if ($categoryid > 0){
1286         // update depth and path
1287         $cat   = get_record('course_categories', 'id', $categoryid);
1288         if ($cat->parent == 0) {
1289             $depth = 0;
1290             $path  = '';
1291         } else if ($depth == 0 ) { // doesn't make sense; get from DB
1292             // this is only called if the $depth parameter looks dodgy
1293             $parent = get_record('course_categories', 'id', $cat->parent);
1294             $path  = $parent->path;
1295             $depth = $parent->depth;
1296         }
1297         $path  = $path . '/' . $categoryid;
1298         $depth = $depth + 1;
1299
1300         if ($cat->path !== $path) {
1301             set_field('course_categories', 'path',  addslashes($path),  'id', $categoryid);
1302         }
1303         if ($cat->depth != $depth) {
1304             set_field('course_categories', 'depth', $depth, 'id', $categoryid);
1305         }
1306     }
1307
1308     // get some basic info about courses in the category
1309     $info = get_record_sql('SELECT MIN(sortorder) AS min,
1310                                    MAX(sortorder) AS max,
1311                                    COUNT(sortorder)  AS count
1312                             FROM ' . $CFG->prefix . 'course
1313                             WHERE category=' . $categoryid);
1314     if (is_object($info)) { // no courses?
1315         $max   = $info->max;
1316         $count = $info->count;
1317         $min   = $info->min;
1318         unset($info);
1319     }
1320
1321     if ($categoryid > 0 && $n==0) { // only passed category so don't shift it
1322         $n = $min;
1323     }
1324
1325     // $hasgap flag indicates whether there's a gap in the sequence
1326     $hasgap    = false;
1327     if ($max-$min+1 != $count) {
1328         $hasgap = true;
1329     }
1330
1331     // $mustshift indicates whether the sequence must be shifted to
1332     // meet its range
1333     $mustshift = false;
1334     if ($min < $n+$tolerance || $min > $n+$tolerance+$catgap ) {
1335         $mustshift = true;
1336     }
1337
1338     // actually sort only if there are courses,
1339     // and we meet one ofthe triggers:
1340     //  - safe flag
1341     //  - they are not in a continuos block
1342     //  - they are too close to the 'bottom'
1343     if ($count && ( $safe || $hasgap || $mustshift ) ) {
1344         // special, optimized case where all we need is to shift
1345         if ( $mustshift && !$safe && !$hasgap) {
1346             $shift = $n + $catgap - $min;
1347             if ($shift < $count) {
1348                 $shift = $count + $catgap;
1349             }
1350             // UPDATE course SET sortorder=sortorder+$shift
1351             execute_sql("UPDATE {$CFG->prefix}course
1352                          SET sortorder=sortorder+$shift
1353                          WHERE category=$categoryid", 0);
1354             $n = $n + $catgap + $count;
1355
1356         } else { // do it slowly
1357             $n = $n + $catgap;
1358             // if the new sequence overlaps the current sequence, lack of transactions
1359             // will stop us -- shift things aside for a moment...
1360             if ($safe || ($n >= $min && $n+$count+1 < $min && $CFG->dbfamily==='mysql')) {
1361                 $shift = $max + $n + 1000;
1362                 execute_sql("UPDATE {$CFG->prefix}course
1363                          SET sortorder=sortorder+$shift
1364                          WHERE category=$categoryid", 0);
1365             }
1366
1367             $courses = get_courses($categoryid, 'c.sortorder ASC', 'c.id,c.sortorder');
1368             begin_sql();
1369             $tx = true; // transaction sanity
1370             foreach ($courses as $course) {
1371                 if ($tx && $course->sortorder != $n ) { // save db traffic
1372                     $tx = $tx && set_field('course', 'sortorder', $n,
1373                                            'id', $course->id);
1374                 }
1375                 $n++;
1376             }
1377             if ($tx) {
1378                 commit_sql();
1379             } else {
1380                 rollback_sql();
1381                 if (!$safe) {
1382                     // if we failed when called with !safe, try
1383                     // to recover calling self with safe=true
1384                     return fix_course_sortorder($categoryid, $n, true, $depth, $path);
1385                 }
1386             }
1387         }
1388     }
1389     set_field('course_categories', 'coursecount', $count, 'id', $categoryid);
1390
1391     // $n could need updating
1392     $max = get_field_sql("SELECT MAX(sortorder) from {$CFG->prefix}course WHERE category=$categoryid");
1393     if ($max > $n) {
1394         $n = $max;
1395     }
1396
1397     if ($categories = get_categories($categoryid)) {
1398         foreach ($categories as $category) {
1399             $n = fix_course_sortorder($category->id, $n, $safe, $depth, $path);
1400         }
1401     }
1402
1403     return $n+1;
1404 }
1405
1406 /**
1407  * Ensure all courses have a valid course category
1408  * useful if a category has been removed manually
1409  **/
1410 function fix_coursecategory_orphans() {
1411
1412     global $CFG;
1413
1414     // Note: the handling of sortorder here is arguably
1415     // open to race conditions. Hard to fix here, unlikely
1416     // to hit anyone in production.
1417
1418     $sql = "SELECT c.id, c.category, c.shortname
1419             FROM {$CFG->prefix}course c
1420             LEFT OUTER JOIN {$CFG->prefix}course_categories cc ON c.category=cc.id
1421             WHERE cc.id IS NULL AND c.id != " . SITEID;
1422
1423     $rs = get_recordset_sql($sql);
1424
1425     if (!rs_EOF($rs)) { // we have some orphans
1426
1427         // the "default" category is the lowest numbered...
1428         $default   = get_field_sql("SELECT MIN(id)
1429                                     FROM {$CFG->prefix}course_categories");
1430         $sortorder = get_field_sql("SELECT MAX(sortorder)
1431                                     FROM {$CFG->prefix}course
1432                                     WHERE category=$default");
1433
1434
1435         begin_sql();
1436         $tx = true;
1437         while ($tx && $course = rs_fetch_next_record($rs)) {
1438             $tx = $tx && set_field('course', 'category',  $default,     'id', $course->id);
1439             $tx = $tx && set_field('course', 'sortorder', ++$sortorder, 'id', $course->id);
1440         }
1441         if ($tx) {
1442             commit_sql();
1443         } else {
1444             rollback_sql();
1445         }
1446     }
1447     rs_close($rs);
1448 }
1449
1450 /**
1451  * List of remote courses that a user has access to via MNET.
1452  * Works only on the IDP
1453  *
1454  * @uses $CFG, $USER
1455  * @return array {@link $COURSE} of course objects
1456  */
1457 function get_my_remotecourses($userid=0) {
1458     global $CFG, $USER;
1459
1460     if (empty($userid)) {
1461         $userid = $USER->id;
1462     }
1463
1464     $sql = "SELECT c.id, c.remoteid, c.shortname, c.fullname,
1465                    c.hostid, c.summary, c.cat_name,
1466                    h.name AS hostname
1467             FROM   {$CFG->prefix}mnet_enrol_course c
1468             JOIN   {$CFG->prefix}mnet_enrol_assignments a ON c.id=a.courseid
1469             JOIN   {$CFG->prefix}mnet_host h        ON c.hostid=h.id
1470             WHERE  a.userid={$userid}";
1471
1472     return get_records_sql($sql);
1473 }
1474
1475 /**
1476  * List of remote hosts that a user has access to via MNET.
1477  * Works on the SP
1478  *
1479  * @uses $CFG, $USER
1480  * @return array of host objects
1481  */
1482 function get_my_remotehosts() {
1483     global $CFG, $USER;
1484
1485     if ($USER->mnethostid == $CFG->mnet_localhost_id) {
1486         return false; // Return nothing on the IDP
1487     }
1488     if (!empty($USER->mnet_foreign_host_array) && is_array($USER->mnet_foreign_host_array)) {
1489         return $USER->mnet_foreign_host_array;
1490     }
1491     return false;
1492 }
1493
1494 /**
1495  * This function creates a default separated/connected scale
1496  *
1497  * This function creates a default separated/connected scale
1498  * so there's something in the database.  The locations of
1499  * strings and files is a bit odd, but this is because we
1500  * need to maintain backward compatibility with many different
1501  * existing language translations and older sites.
1502  *
1503  * @uses $CFG
1504  */
1505 function make_default_scale() {
1506
1507     global $CFG;
1508
1509     $defaultscale = NULL;
1510     $defaultscale->courseid = 0;
1511     $defaultscale->userid = 0;
1512     $defaultscale->name  = get_string('separateandconnected');
1513     $defaultscale->scale = get_string('postrating1', 'forum').','.
1514                            get_string('postrating2', 'forum').','.
1515                            get_string('postrating3', 'forum');
1516     $defaultscale->timemodified = time();
1517
1518     /// Read in the big description from the file.  Note this is not
1519     /// HTML (despite the file extension) but Moodle format text.
1520     $parentlang = get_string('parentlanguage');
1521     if ($parentlang[0] == '[') {
1522         $parentlang = '';
1523     }
1524     if (is_readable($CFG->dataroot .'/lang/'. $CFG->lang .'/help/forum/ratings.html')) {
1525         $file = file($CFG->dataroot .'/lang/'. $CFG->lang .'/help/forum/ratings.html');
1526     } else if (is_readable($CFG->dirroot .'/lang/'. $CFG->lang .'/help/forum/ratings.html')) {
1527         $file = file($CFG->dirroot .'/lang/'. $CFG->lang .'/help/forum/ratings.html');
1528     } else if ($parentlang and is_readable($CFG->dataroot .'/lang/'. $parentlang .'/help/forum/ratings.html')) {
1529         $file = file($CFG->dataroot .'/lang/'. $parentlang .'/help/forum/ratings.html');
1530     } else if ($parentlang and is_readable($CFG->dirroot .'/lang/'. $parentlang .'/help/forum/ratings.html')) {
1531         $file = file($CFG->dirroot .'/lang/'. $parentlang .'/help/forum/ratings.html');
1532     } else if (is_readable($CFG->dirroot .'/lang/en_utf8/help/forum/ratings.html')) {
1533         $file = file($CFG->dirroot .'/lang/en_utf8/help/forum/ratings.html');
1534     } else {
1535         $file = '';
1536     }
1537
1538     $defaultscale->description = addslashes(implode('', $file));
1539
1540     if ($defaultscale->id = insert_record('scale', $defaultscale)) {
1541         execute_sql('UPDATE '. $CFG->prefix .'forum SET scale = \''. $defaultscale->id .'\'', false);
1542     }
1543 }
1544
1545
1546 /**
1547  * Returns a menu of all available scales from the site as well as the given course
1548  *
1549  * @uses $CFG
1550  * @param int $courseid The id of the course as found in the 'course' table.
1551  * @return object
1552  */
1553 function get_scales_menu($courseid=0) {
1554
1555     global $CFG;
1556
1557     $sql = "SELECT id, name FROM {$CFG->prefix}scale
1558              WHERE courseid = '0' or courseid = '$courseid'
1559           ORDER BY courseid ASC, name ASC";
1560
1561     if ($scales = get_records_sql_menu($sql)) {
1562         return $scales;
1563     }
1564
1565     make_default_scale();
1566
1567     return get_records_sql_menu($sql);
1568 }
1569
1570
1571
1572 /**
1573  * Given a set of timezone records, put them in the database,  replacing what is there
1574  *
1575  * @uses $CFG
1576  * @param array $timezones An array of timezone records
1577  */
1578 function update_timezone_records($timezones) {
1579 /// Given a set of timezone records, put them in the database
1580
1581     global $CFG;
1582
1583 /// Clear out all the old stuff
1584     execute_sql('TRUNCATE TABLE '.$CFG->prefix.'timezone', false);
1585
1586 /// Insert all the new stuff
1587     foreach ($timezones as $timezone) {
1588         if (is_array($timezone)) {
1589             $timezone = (object)$timezone;
1590         }
1591         insert_record('timezone', $timezone);
1592     }
1593 }
1594
1595
1596 /// MODULE FUNCTIONS /////////////////////////////////////////////////
1597
1598 /**
1599  * Just gets a raw list of all modules in a course
1600  *
1601  * @uses $CFG
1602  * @param int $courseid The id of the course as found in the 'course' table.
1603  * @return object
1604  */
1605 function get_course_mods($courseid) {
1606     global $CFG;
1607
1608     if (empty($courseid)) {
1609         return false; // avoid warnings
1610     }
1611
1612     return get_records_sql("SELECT cm.*, m.name as modname
1613                             FROM {$CFG->prefix}modules m,
1614                                  {$CFG->prefix}course_modules cm
1615                             WHERE cm.course = ".intval($courseid)."
1616                             AND cm.module = m.id AND m.visible = 1"); // no disabled mods
1617 }
1618
1619
1620 /**
1621  * Given an id of a course module, finds the coursemodule description
1622  *
1623  * @param string $modulename name of module type, eg. resource, assignment,...
1624  * @param int $cmid course module id (id in course_modules table)
1625  * @param int $courseid optional course id for extra validation
1626  * @return object course module instance with instance and module name
1627  */
1628 function get_coursemodule_from_id($modulename, $cmid, $courseid=0) {
1629
1630     global $CFG;
1631
1632     $courseselect = ($courseid) ? 'cm.course = '.intval($courseid).' AND ' : '';
1633
1634     return get_record_sql("SELECT cm.*, m.name, md.name as modname
1635                            FROM {$CFG->prefix}course_modules cm,
1636                                 {$CFG->prefix}modules md,
1637                                 {$CFG->prefix}$modulename m
1638                            WHERE $courseselect
1639                                  cm.id = ".intval($cmid)." AND
1640                                  cm.instance = m.id AND
1641                                  md.name = '$modulename' AND
1642                                  md.id = cm.module");
1643 }
1644
1645 /**
1646  * Given an instance number of a module, finds the coursemodule description
1647  *
1648  * @param string $modulename name of module type, eg. resource, assignment,...
1649  * @param int $instance module instance number (id in resource, assignment etc. table)
1650  * @param int $courseid optional course id for extra validation
1651  * @return object course module instance with instance and module name
1652  */
1653 function get_coursemodule_from_instance($modulename, $instance, $courseid=0) {
1654
1655     global $CFG;
1656
1657     $courseselect = ($courseid) ? 'cm.course = '.intval($courseid).' AND ' : '';
1658
1659     return get_record_sql("SELECT cm.*, m.name, md.name as modname
1660                            FROM {$CFG->prefix}course_modules cm,
1661                                 {$CFG->prefix}modules md,
1662                                 {$CFG->prefix}$modulename m
1663                            WHERE $courseselect
1664                                  cm.instance = m.id AND
1665                                  md.name = '$modulename' AND
1666                                  md.id = cm.module AND
1667                                  m.id = ".intval($instance));
1668
1669 }
1670
1671 /**
1672  * Returns all course modules of given activity in course
1673  * @param string $modulename (forum, quiz, etc.)
1674  * @param int $courseid
1675  * @param string $extrafields extra fields starting with m.
1676  * @return array of cm objects, false if not found or error
1677  */
1678 function get_coursemodules_in_course($modulename, $courseid, $extrafields='') {
1679     global $CFG;
1680
1681     if (!empty($extrafields)) {
1682         $extrafields = ", $extrafields";
1683     }
1684     return get_records_sql("SELECT cm.*, m.name, md.name as modname $extrafields
1685                               FROM {$CFG->prefix}course_modules cm,
1686                                    {$CFG->prefix}modules md,
1687                                    {$CFG->prefix}$modulename m
1688                              WHERE cm.course = $courseid AND
1689                                    cm.instance = m.id AND
1690                                    md.name = '$modulename' AND
1691                                    md.id = cm.module");
1692 }
1693
1694 /**
1695  * Returns an array of all the active instances of a particular module in given courses, sorted in the order they are defined
1696  *
1697  * Returns an array of all the active instances of a particular
1698  * module in given courses, sorted in the order they are defined
1699  * in the course. Returns an empty array on any errors.
1700  *
1701  * The returned objects includle the columns cw.section, cm.visible,
1702  * cm.groupmode and cm.groupingid, cm.groupmembersonly, and are indexed by cm.id.
1703  *
1704  * @param string $modulename The name of the module to get instances for
1705  * @param array $courses an array of course objects.
1706  * @return array of module instance objects, including some extra fields from the course_modules
1707  *          and course_sections tables, or an empty array if an error occurred.
1708  */
1709 function get_all_instances_in_courses($modulename, $courses, $userid=NULL, $includeinvisible=false) {
1710     global $CFG;
1711
1712     $outputarray = array();
1713
1714     if (empty($courses) || !is_array($courses) || count($courses) == 0) {
1715         return $outputarray;
1716     }
1717
1718     if (!$rawmods = get_records_sql("SELECT cm.id AS coursemodule, m.*, cw.section, cm.visible AS visible,
1719                                             cm.groupmode, cm.groupingid, cm.groupmembersonly
1720                                        FROM {$CFG->prefix}course_modules cm,
1721                                             {$CFG->prefix}course_sections cw,
1722                                             {$CFG->prefix}modules md,
1723                                             {$CFG->prefix}$modulename m
1724                                       WHERE cm.course IN (".implode(',',array_keys($courses)).") AND
1725                                             cm.instance = m.id AND
1726                                             cm.section = cw.id AND
1727                                             md.name = '$modulename' AND
1728                                             md.id = cm.module")) {
1729         return $outputarray;
1730     }
1731
1732     require_once($CFG->dirroot.'/course/lib.php');
1733
1734     foreach ($courses as $course) {
1735         $modinfo = get_fast_modinfo($course, $userid);
1736
1737         if (empty($modinfo->instances[$modulename])) {
1738             continue;
1739         }
1740
1741         foreach ($modinfo->instances[$modulename] as $cm) {
1742             if (!$includeinvisible and !$cm->uservisible) {
1743                 continue;
1744             }
1745             if (!isset($rawmods[$cm->id])) {
1746                 continue;
1747             }
1748             $instance = $rawmods[$cm->id];
1749             if (!empty($cm->extra)) {
1750                 $instance->extra = urlencode($cm->extra); // bc compatibility
1751             }
1752             $outputarray[] = $instance;
1753         }
1754     }
1755
1756     return $outputarray;
1757 }
1758
1759 /**
1760  * Returns an array of all the active instances of a particular module in a given course,
1761  * sorted in the order they are defined.
1762  *
1763  * Returns an array of all the active instances of a particular
1764  * module in a given course, sorted in the order they are defined
1765  * in the course. Returns an empty array on any errors.
1766  *
1767  * The returned objects includle the columns cw.section, cm.visible,
1768  * cm.groupmode and cm.groupingid, cm.groupmembersonly, and are indexed by cm.id.
1769  *
1770  * @param string $modulename The name of the module to get instances for
1771  * @param object $course The course obect.
1772  * @return array of module instance objects, including some extra fields from the course_modules
1773  *          and course_sections tables, or an empty array if an error occurred.
1774  */
1775 function get_all_instances_in_course($modulename, $course, $userid=NULL, $includeinvisible=false) {
1776     return get_all_instances_in_courses($modulename, array($course->id => $course), $userid, $includeinvisible);
1777 }
1778
1779
1780 /**
1781  * Determine whether a module instance is visible within a course
1782  *
1783  * Given a valid module object with info about the id and course,
1784  * and the module's type (eg "forum") returns whether the object
1785  * is visible or not, groupmembersonly visibility not tested
1786  *
1787  * @uses $CFG
1788  * @param $moduletype Name of the module eg 'forum'
1789  * @param $module Object which is the instance of the module
1790  * @return bool
1791  */
1792 function instance_is_visible($moduletype, $module) {
1793
1794     global $CFG;
1795
1796     if (!empty($module->id)) {
1797         if ($records = get_records_sql("SELECT cm.instance, cm.visible, cm.groupingid, cm.id, cm.groupmembersonly, cm.course
1798                                         FROM {$CFG->prefix}course_modules cm,
1799                                              {$CFG->prefix}modules m
1800                                        WHERE cm.course = '$module->course' AND
1801                                              cm.module = m.id AND
1802                                              m.name = '$moduletype' AND
1803                                              cm.instance = '$module->id'")) {
1804
1805             foreach ($records as $record) { // there should only be one - use the first one
1806                 return $record->visible;
1807             }
1808         }
1809     }
1810     return true;  // visible by default!
1811 }
1812
1813 /**
1814  * Determine whether a course module is visible within a course,
1815  * this is different from instance_is_visible() - faster and visibility for user
1816  *
1817  * @param object $cm object
1818  * @param int $userid empty means current user
1819  * @return bool
1820  */
1821 function coursemodule_visible_for_user($cm, $userid=0) {
1822     global $USER;
1823
1824     if (empty($cm->id)) {
1825         debugging("Incorrect course module parameter!", DEBUG_DEVELOPER);
1826         return false;
1827     }
1828     if (empty($userid)) {
1829         $userid = $USER->id;
1830     }
1831     if (!$cm->visible and !has_capability('moodle/course:viewhiddenactivities', get_context_instance(CONTEXT_MODULE, $cm->id), $userid)) {
1832         return false;
1833     }
1834     return groups_course_module_visible($cm, $userid);
1835 }
1836
1837
1838
1839
1840 /// LOG FUNCTIONS /////////////////////////////////////////////////////
1841
1842
1843 /**
1844  * Add an entry to the log table.
1845  *
1846  * Add an entry to the log table.  These are "action" focussed rather
1847  * than web server hits, and provide a way to easily reconstruct what
1848  * any particular student has been doing.
1849  *
1850  * @uses $CFG
1851  * @uses $USER
1852  * @uses $db
1853  * @uses $REMOTE_ADDR
1854  * @uses SITEID
1855  * @param    int     $courseid  The course id
1856  * @param    string  $module  The module name - e.g. forum, journal, resource, course, user etc
1857  * @param    string  $action  'view', 'update', 'add' or 'delete', possibly followed by another word to clarify.
1858  * @param    string  $url     The file and parameters used to see the results of the action
1859  * @param    string  $info    Additional description information
1860  * @param    string  $cm      The course_module->id if there is one
1861  * @param    string  $user    If log regards $user other than $USER
1862  */
1863 function add_to_log($courseid, $module, $action, $url='', $info='', $cm=0, $user=0) {
1864     // Note that this function intentionally does not follow the normal Moodle DB access idioms.
1865     // This is for a good reason: it is the most frequently used DB update function,
1866     // so it has been optimised for speed.
1867     global $db, $CFG, $USER;
1868
1869     if ($cm === '' || is_null($cm)) { // postgres won't translate empty string to its default
1870         $cm = 0;
1871     }
1872
1873     if ($user) {
1874         $userid = $user;
1875     } else {
1876         if (!empty($USER->realuser)) {  // Don't log
1877             return;
1878         }
1879         $userid = empty($USER->id) ? '0' : $USER->id;
1880     }
1881
1882     $REMOTE_ADDR = getremoteaddr();
1883
1884     $timenow = time();
1885     $info = addslashes($info);
1886     if (!empty($url)) { // could break doing html_entity_decode on an empty var.
1887         $url = html_entity_decode($url); // for php < 4.3.0 this is defined in moodlelib.php
1888     }
1889
1890     // Restrict length of log lines to the space actually available in the
1891     // database so that it doesn't cause a DB error. Log a warning so that
1892     // developers can avoid doing things which are likely to cause this on a
1893     // routine basis.
1894     $tl=textlib_get_instance();
1895     if(!empty($info) && $tl->strlen($info)>255) {
1896         $info=$tl->substr($info,0,252).'...';
1897         debugging('Warning: logged very long info',DEBUG_DEVELOPER);
1898     }
1899     // Note: Unlike $info, URL appears to be already slashed before this function
1900     // is called. Since database limits are for the data before slashes, we need
1901     // to remove them...
1902     $url=stripslashes($url);
1903     // If the 100 field size is changed, also need to alter print_log in course/lib.php
1904     if(!empty($url) && $tl->strlen($url)>100) {
1905         $url=$tl->substr($url,0,97).'...';
1906         debugging('Warning: logged very long URL',DEBUG_DEVELOPER);
1907     }
1908     $url=addslashes($url);
1909
1910     if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; $PERF->logwrites++;};
1911
1912     if ($CFG->type = 'oci8po') {
1913         if (empty($info)) {
1914             $info = ' ';
1915         }
1916     }
1917     $sql ='INSERT INTO '. $CFG->prefix .'log (time, userid, course, ip, module, cmid, action, url, info)
1918         VALUES (' . "'$timenow', '$userid', '$courseid', '$REMOTE_ADDR', '$module', '$cm', '$action', '$url', '$info')";
1919
1920     $result = $db->Execute($sql);
1921
1922     // MDL-11893, alert $CFG->supportemail if insert into log failed
1923     if (!$result && $CFG->supportemail) {
1924         $site = get_site();
1925         $subject = 'Insert into log failed at your moodle site '.$site->fullname;
1926         $message = "Insert into log table failed at ". date('l dS \of F Y h:i:s A') .".\n It is possible that your disk is full.\n\n";
1927         $message .= "The failed SQL is:\n\n" . $sql;
1928
1929         // email_to_user is not usable because email_to_user tries to write to the logs table,
1930         // and this will get caught in an infinite loop, if disk is full
1931         if (empty($CFG->noemailever)) {
1932             $lasttime = get_config('admin', 'lastloginserterrormail');
1933             if(empty($lasttime) || time() - $lasttime > 60*60*24) { // limit to 1 email per day
1934                 mail($CFG->supportemail, $subject, $message);
1935                 set_config('lastloginserterrormail', time(), 'admin');
1936             }
1937         }
1938     }
1939
1940     if (!$result) {
1941         debugging('Error: Could not insert a new entry to the Moodle log', DEBUG_ALL);
1942     }
1943
1944 }
1945
1946 /**
1947  * Store user last access times - called when use enters a course or site
1948  *
1949  * Note: we use ADOdb code directly in this function to save some CPU
1950  * cycles here and there. They are simple operations not needing any
1951  * of the postprocessing performed by dmllib.php
1952  *
1953  * @param int $courseid, empty means site
1954  * @return void
1955  */
1956 function user_accesstime_log($courseid=0) {
1957
1958     global $USER, $CFG, $PERF, $db;
1959
1960     if (!isloggedin() or !empty($USER->realuser)) {
1961         // no access tracking
1962         return;
1963     }
1964
1965     if (empty($courseid)) {
1966         $courseid = SITEID;
1967     }
1968
1969     $timenow = time();
1970
1971 /// Store site lastaccess time for the current user
1972     if ($timenow - $USER->lastaccess > LASTACCESS_UPDATE_SECS) {
1973     /// Update $USER->lastaccess for next checks
1974         $USER->lastaccess = $timenow;
1975         if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++;};
1976
1977         $remoteaddr = getremoteaddr();
1978         if ($db->Execute("UPDATE {$CFG->prefix}user
1979                              SET lastip = '$remoteaddr', lastaccess = $timenow
1980                            WHERE id = $USER->id")) {
1981         } else {
1982             debugging('Error: Could not update global user lastaccess information');  // Don't throw an error
1983         }
1984     /// Remove this record from record cache since it will change
1985         if (!empty($CFG->rcache)) {
1986             rcache_unset('user', $USER->id);
1987         }
1988     }
1989
1990     if ($courseid == SITEID) {
1991     ///  no user_lastaccess for frontpage
1992         return;
1993     }
1994
1995 /// Store course lastaccess times for the current user
1996     if (empty($USER->currentcourseaccess[$courseid]) or ($timenow - $USER->currentcourseaccess[$courseid] > LASTACCESS_UPDATE_SECS)) {
1997         if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
1998
1999         $exists = false; // To detect if the user_lastaccess record exists or no
2000         if ($rs = $db->Execute("SELECT timeaccess
2001                                   FROM {$CFG->prefix}user_lastaccess
2002                                  WHERE userid = $USER->id AND courseid = $courseid")) {
2003             if (!$rs->EOF) {
2004                 $exists = true;
2005                 $lastaccess = reset($rs->fields);
2006                 if ($timenow - $lastaccess <  LASTACCESS_UPDATE_SECS) {
2007                 /// no need to update now, it was updated recently in concurrent login ;-)
2008                     $rs->Close();
2009                     return;
2010                 }
2011             }
2012             $rs->Close();
2013         }
2014
2015     /// Update course lastaccess for next checks
2016         $USER->currentcourseaccess[$courseid] = $timenow;
2017         if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
2018
2019         if ($exists) { // user_lastaccess record exists, update it
2020             if ($db->Execute("UPDATE {$CFG->prefix}user_lastaccess
2021                                  SET timeaccess = $timenow
2022                                WHERE userid = $USER->id AND courseid = $courseid")) {
2023             } else {
2024                 debugging('Error: Could not update course user lastacess information');  // Don't throw an error
2025             }
2026
2027         } else { // user lastaccess record doesn't exist, insert it
2028             if ($db->Execute("INSERT INTO {$CFG->prefix}user_lastaccess
2029                                      (userid, courseid, timeaccess)
2030                               VALUES ($USER->id, $courseid, $timenow)")) {
2031             } else {
2032                 debugging('Error: Could not insert course user lastaccess information');  // Don't throw an error
2033             }
2034         }
2035     }
2036 }
2037
2038 /**
2039  * Select all log records based on SQL criteria
2040  *
2041  * @uses $CFG
2042  * @param string $select SQL select criteria
2043  * @param string $order SQL order by clause to sort the records returned
2044  * @param string $limitfrom ?
2045  * @param int $limitnum ?
2046  * @param int $totalcount Passed in by reference.
2047  * @return object
2048  * @todo Finish documenting this function
2049  */
2050 function get_logs($select, $order='l.time DESC', $limitfrom='', $limitnum='', &$totalcount) {
2051     global $CFG;
2052
2053     if ($order) {
2054         $order = 'ORDER BY '. $order;
2055     }
2056
2057     $selectsql = $CFG->prefix .'log l LEFT JOIN '. $CFG->prefix .'user u ON l.userid = u.id '. ((strlen($select) > 0) ? 'WHERE '. $select : '');
2058     $countsql = $CFG->prefix.'log l '.((strlen($select) > 0) ? ' WHERE '. $select : '');
2059
2060     $totalcount = count_records_sql("SELECT COUNT(*) FROM $countsql");
2061
2062     return get_records_sql('SELECT l.*, u.firstname, u.lastname, u.picture
2063                                 FROM '. $selectsql .' '. $order, $limitfrom, $limitnum) ;
2064 }
2065
2066
2067 /**
2068  * Select all log records for a given course and user
2069  *
2070  * @uses $CFG
2071  * @uses DAYSECS
2072  * @param int $userid The id of the user as found in the 'user' table.
2073  * @param int $courseid The id of the course as found in the 'course' table.
2074  * @param string $coursestart ?
2075  * @todo Finish documenting this function
2076  */
2077 function get_logs_usercourse($userid, $courseid, $coursestart) {
2078     global $CFG;
2079
2080     if ($courseid) {
2081         $courseselect = ' AND course = \''. $courseid .'\' ';
2082     } else {
2083         $courseselect = '';
2084     }
2085
2086     return get_records_sql("SELECT floor((time - $coursestart)/". DAYSECS .") as day, count(*) as num
2087                             FROM {$CFG->prefix}log
2088                            WHERE userid = '$userid'
2089                              AND time > '$coursestart' $courseselect
2090                         GROUP BY floor((time - $coursestart)/". DAYSECS .") ");
2091 }
2092
2093 /**
2094  * Select all log records for a given course, user, and day
2095  *
2096  * @uses $CFG
2097  * @uses HOURSECS
2098  * @param int $userid The id of the user as found in the 'user' table.
2099  * @param int $courseid The id of the course as found in the 'course' table.
2100  * @param string $daystart ?
2101  * @return object
2102  * @todo Finish documenting this function
2103  */
2104 function get_logs_userday($userid, $courseid, $daystart) {
2105     global $CFG;
2106
2107     if ($courseid) {
2108         $courseselect = ' AND course = \''. $courseid .'\' ';
2109     } else {
2110         $courseselect = '';
2111     }
2112
2113     return get_records_sql("SELECT floor((time - $daystart)/". HOURSECS .") as hour, count(*) as num
2114                             FROM {$CFG->prefix}log
2115                            WHERE userid = '$userid'
2116                              AND time > '$daystart' $courseselect
2117                         GROUP BY floor((time - $daystart)/". HOURSECS .") ");
2118 }
2119
2120 /**
2121  * Returns an object with counts of failed login attempts
2122  *
2123  * Returns information about failed login attempts.  If the current user is
2124  * an admin, then two numbers are returned:  the number of attempts and the
2125  * number of accounts.  For non-admins, only the attempts on the given user
2126  * are shown.
2127  *
2128  * @param string $mode Either 'admin', 'teacher' or 'everybody'
2129  * @param string $username The username we are searching for
2130  * @param string $lastlogin The date from which we are searching
2131  * @return int
2132  */
2133 function count_login_failures($mode, $username, $lastlogin) {
2134
2135     $select = 'module=\'login\' AND action=\'error\' AND time > '. $lastlogin;
2136
2137     if (has_capability('moodle/site:config', get_context_instance(CONTEXT_SYSTEM))) {    // Return information about all accounts
2138         if ($count->attempts = count_records_select('log', $select)) {
2139             $count->accounts = count_records_select('log', $select, 'COUNT(DISTINCT info)');
2140             return $count;
2141         }
2142     } else if ($mode == 'everybody' or ($mode == 'teacher' and isteacherinanycourse())) {
2143         if ($count->attempts = count_records_select('log', $select .' AND info = \''. $username .'\'')) {
2144             return $count;
2145         }
2146     }
2147     return NULL;
2148 }
2149
2150
2151 /// GENERAL HELPFUL THINGS  ///////////////////////////////////
2152
2153 /**
2154  * Dump a given object's information in a PRE block.
2155  *
2156  * Mostly just used for debugging.
2157  *
2158  * @param mixed $object The data to be printed
2159  */
2160 function print_object($object) {
2161     echo '<pre class="notifytiny">' . htmlspecialchars(print_r($object,true)) . '</pre>';
2162 }
2163
2164 /*
2165  * Check whether a course is visible through its parents
2166  * path.
2167  *
2168  * Notes:
2169  *
2170  * - All we need from the course is ->category. _However_
2171  *   if the course object has a categorypath property,
2172  *   we'll save a dbquery
2173  *
2174  * - If we return false, you'll still need to check if
2175  *   the user can has the 'moodle/category:visibility'
2176  *   capability...
2177  *
2178  * - Will generate 2 DB calls.
2179  *
2180  * - It does have a small local cache, however...
2181  *
2182  * - Do NOT call this over many courses as it'll generate
2183  *   DB traffic. Instead, see what get_my_courses() does.
2184  *
2185  * @param mixed $object A course object
2186  * @return bool
2187  */
2188 function course_parent_visible($course = null) {
2189     global $CFG;
2190     //return true;
2191     static $mycache;
2192
2193     if (!is_object($course)) {
2194         return true;
2195     }
2196     if (!empty($CFG->allowvisiblecoursesinhiddencategories)) {
2197         return true;
2198     }
2199
2200     if (!isset($mycache)) {
2201         $mycache = array();
2202     } else {
2203         // cast to force assoc array
2204         $k = (string)$course->category;
2205         if (isset($mycache[$k])) {
2206             return $mycache[$k];
2207         }
2208     }
2209
2210     if (isset($course->categorypath)) {
2211         $path = $course->categorypath;
2212     } else {
2213         $path = get_field('course_categories', 'path',
2214                           'id', $course->category);
2215     }
2216     $catids = substr($path,1); // strip leading slash
2217     $catids = str_replace('/',',',$catids);
2218
2219     $sql = "SELECT MIN(visible)
2220             FROM {$CFG->prefix}course_categories
2221             WHERE id IN ($catids)";
2222     $vis = get_field_sql($sql);
2223
2224     // cast to force assoc array
2225     $k = (string)$course->category;
2226     $mycache[$k] = $vis;
2227
2228     return $vis;
2229 }
2230
2231 /**
2232  * This function is the official hook inside XMLDB stuff to delegate its debug to one
2233  * external function.
2234  *
2235  * Any script can avoid calls to this function by defining XMLDB_SKIP_DEBUG_HOOK before
2236  * using XMLDB classes. Obviously, also, if this function doesn't exist, it isn't invoked ;-)
2237  *
2238  * @param $message string contains the error message
2239  * @param $object object XMLDB object that fired the debug
2240  */
2241 function xmldb_debug($message, $object) {
2242
2243     debugging($message, DEBUG_DEVELOPER);
2244 }
2245
2246 /**
2247  * true or false function to see if user can create any courses at all
2248  * @return bool
2249  */
2250 function user_can_create_courses() {
2251     global $USER;
2252     // if user has course creation capability at any site or course cat, then return true;
2253
2254     if (has_capability('moodle/course:create', get_context_instance(CONTEXT_SYSTEM))) {
2255         return true;
2256     } else {
2257         return (bool) count(get_creatable_categories());
2258     }
2259
2260 }
2261
2262 /**
2263  * get the list of categories the current user can create courses in
2264  * @return array
2265  */
2266 function get_creatable_categories() {
2267
2268     $creatablecats = array();
2269     if ($cats = get_records('course_categories')) {
2270         foreach ($cats as $cat) {
2271             if (has_capability('moodle/course:create', get_context_instance(CONTEXT_COURSECAT, $cat->id))) {
2272                 $creatablecats[$cat->id] = $cat->name;
2273             }
2274         }
2275     }
2276     return $creatablecats;
2277 }
2278
2279 // vim:autoindent:expandtab:shiftwidth=4:tabstop=4:tw=140:
2280 ?>