Search moodle.org's
Developer Documentation

See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.

Differences Between: [Versions 310 and 401] [Versions 311 and 401] [Versions 39 and 401] [Versions 400 and 401] [Versions 401 and 402] [Versions 401 and 403]

   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   * @package    moodlecore
  20   * @subpackage backup-dbops
  21   * @copyright  2010 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  /**
  26   * Base abstract class for all the helper classes providing DB operations
  27   *
  28   * TODO: Finish phpdocs
  29   */
  30  abstract class restore_dbops {
  31      /**
  32       * Keep cache of backup records.
  33       * @var array
  34       * @todo MDL-25290 static should be replaced with MUC code.
  35       */
  36      private static $backupidscache = array();
  37      /**
  38       * Keep track of backup ids which are cached.
  39       * @var array
  40       * @todo MDL-25290 static should be replaced with MUC code.
  41       */
  42      private static $backupidsexist = array();
  43      /**
  44       * Count is expensive, so manually keeping track of
  45       * backupidscache, to avoid memory issues.
  46       * @var int
  47       * @todo MDL-25290 static should be replaced with MUC code.
  48       */
  49      private static $backupidscachesize = 2048;
  50      /**
  51       * Count is expensive, so manually keeping track of
  52       * backupidsexist, to avoid memory issues.
  53       * @var int
  54       * @todo MDL-25290 static should be replaced with MUC code.
  55       */
  56      private static $backupidsexistsize = 10240;
  57      /**
  58       * Slice backupids cache to add more data.
  59       * @var int
  60       * @todo MDL-25290 static should be replaced with MUC code.
  61       */
  62      private static $backupidsslice = 512;
  63  
  64      /**
  65       * Return one array containing all the tasks that have been included
  66       * in the restore process. Note that these tasks aren't built (they
  67       * haven't steps nor ids data available)
  68       */
  69      public static function get_included_tasks($restoreid) {
  70          $rc = restore_controller_dbops::load_controller($restoreid);
  71          $tasks = $rc->get_plan()->get_tasks();
  72          $includedtasks = array();
  73          foreach ($tasks as $key => $task) {
  74              // Calculate if the task is being included
  75              $included = false;
  76              // blocks, based in blocks setting and parent activity/course
  77              if ($task instanceof restore_block_task) {
  78                  if (!$task->get_setting_value('blocks')) { // Blocks not included, continue
  79                      continue;
  80                  }
  81                  $parent = basename(dirname(dirname($task->get_taskbasepath())));
  82                  if ($parent == 'course') { // Parent is course, always included if present
  83                      $included = true;
  84  
  85                  } else { // Look for activity_included setting
  86                      $included = $task->get_setting_value($parent . '_included');
  87                  }
  88  
  89              // ativities, based on included setting
  90              } else if ($task instanceof restore_activity_task) {
  91                  $included = $task->get_setting_value('included');
  92  
  93              // sections, based on included setting
  94              } else if ($task instanceof restore_section_task) {
  95                  $included = $task->get_setting_value('included');
  96  
  97              // course always included if present
  98              } else if ($task instanceof restore_course_task) {
  99                  $included = true;
 100              }
 101  
 102              // If included, add it
 103              if ($included) {
 104                  $includedtasks[] = clone($task); // A clone is enough. In fact we only need the basepath.
 105              }
 106          }
 107          $rc->destroy(); // Always need to destroy.
 108  
 109          return $includedtasks;
 110      }
 111  
 112      /**
 113       * Load one inforef.xml file to backup_ids table for future reference
 114       *
 115       * @param string $restoreid Restore id
 116       * @param string $inforeffile File path
 117       * @param \core\progress\base $progress Progress tracker
 118       */
 119      public static function load_inforef_to_tempids($restoreid, $inforeffile,
 120              \core\progress\base $progress = null) {
 121  
 122          if (!file_exists($inforeffile)) { // Shouldn't happen ever, but...
 123              throw new backup_helper_exception('missing_inforef_xml_file', $inforeffile);
 124          }
 125  
 126          // Set up progress tracking (indeterminate).
 127          if (!$progress) {
 128              $progress = new \core\progress\none();
 129          }
 130          $progress->start_progress('Loading inforef.xml file');
 131  
 132          // Let's parse, custom processor will do its work, sending info to DB
 133          $xmlparser = new progressive_parser();
 134          $xmlparser->set_file($inforeffile);
 135          $xmlprocessor = new restore_inforef_parser_processor($restoreid);
 136          $xmlparser->set_processor($xmlprocessor);
 137          $xmlparser->set_progress($progress);
 138          $xmlparser->process();
 139  
 140          // Finish progress
 141          $progress->end_progress();
 142      }
 143  
 144      /**
 145       * Load the needed role.xml file to backup_ids table for future reference
 146       */
 147      public static function load_roles_to_tempids($restoreid, $rolesfile) {
 148  
 149          if (!file_exists($rolesfile)) { // Shouldn't happen ever, but...
 150              throw new backup_helper_exception('missing_roles_xml_file', $rolesfile);
 151          }
 152          // Let's parse, custom processor will do its work, sending info to DB
 153          $xmlparser = new progressive_parser();
 154          $xmlparser->set_file($rolesfile);
 155          $xmlprocessor = new restore_roles_parser_processor($restoreid);
 156          $xmlparser->set_processor($xmlprocessor);
 157          $xmlparser->process();
 158      }
 159  
 160      /**
 161       * Precheck the loaded roles, return empty array if everything is ok, and
 162       * array with 'errors', 'warnings' elements (suitable to be used by restore_prechecks)
 163       * with any problem found. At the same time, store all the mapping into backup_ids_temp
 164       * and also put the information into $rolemappings (controller->info), so it can be reworked later by
 165       * post-precheck stages while at the same time accept modified info in the same object coming from UI
 166       */
 167      public static function precheck_included_roles($restoreid, $courseid, $userid, $samesite, $rolemappings) {
 168          global $DB;
 169  
 170          $problems = array(); // To store warnings/errors
 171  
 172          // Get loaded roles from backup_ids
 173          $rs = $DB->get_recordset('backup_ids_temp', array('backupid' => $restoreid, 'itemname' => 'role'), '', 'itemid, info');
 174          foreach ($rs as $recrole) {
 175              // If the rolemappings->modified flag is set, that means that we are coming from
 176              // manually modified mappings (by UI), so accept those mappings an put them to backup_ids
 177              if ($rolemappings->modified) {
 178                  $target = $rolemappings->mappings[$recrole->itemid]->targetroleid;
 179                  self::set_backup_ids_record($restoreid, 'role', $recrole->itemid, $target);
 180  
 181              // Else, we haven't any info coming from UI, let's calculate the mappings, matching
 182              // in multiple ways and checking permissions. Note mapping to 0 means "skip"
 183              } else {
 184                  $role = (object)backup_controller_dbops::decode_backup_temp_info($recrole->info);
 185                  $match = self::get_best_assignable_role($role, $courseid, $userid, $samesite);
 186                  // Send match to backup_ids
 187                  self::set_backup_ids_record($restoreid, 'role', $recrole->itemid, $match);
 188                  // Build the rolemappings element for controller
 189                  unset($role->id);
 190                  unset($role->nameincourse);
 191                  $role->targetroleid = $match;
 192                  $rolemappings->mappings[$recrole->itemid] = $role;
 193                  // Prepare warning if no match found
 194                  if (!$match) {
 195                      $problems['warnings'][] = get_string('cannotfindassignablerole', 'backup', $role->name);
 196                  }
 197              }
 198          }
 199          $rs->close();
 200          return $problems;
 201      }
 202  
 203      /**
 204       * Return cached backup id's
 205       *
 206       * @param int $restoreid id of backup
 207       * @param string $itemname name of the item
 208       * @param int $itemid id of item
 209       * @return array backup id's
 210       * @todo MDL-25290 replace static backupids* with MUC code
 211       */
 212      protected static function get_backup_ids_cached($restoreid, $itemname, $itemid) {
 213          global $DB;
 214  
 215          $key = "$itemid $itemname $restoreid";
 216  
 217          // If record exists in cache then return.
 218          if (isset(self::$backupidsexist[$key]) && isset(self::$backupidscache[$key])) {
 219              // Return a copy of cached data, to avoid any alterations in cached data.
 220              return clone self::$backupidscache[$key];
 221          }
 222  
 223          // Clean cache, if it's full.
 224          if (self::$backupidscachesize <= 0) {
 225              // Remove some records, to keep memory in limit.
 226              self::$backupidscache = array_slice(self::$backupidscache, self::$backupidsslice, null, true);
 227              self::$backupidscachesize = self::$backupidscachesize + self::$backupidsslice;
 228          }
 229          if (self::$backupidsexistsize <= 0) {
 230              self::$backupidsexist = array_slice(self::$backupidsexist, self::$backupidsslice, null, true);
 231              self::$backupidsexistsize = self::$backupidsexistsize + self::$backupidsslice;
 232          }
 233  
 234          // Retrive record from database.
 235          $record = array(
 236              'backupid' => $restoreid,
 237              'itemname' => $itemname,
 238              'itemid'   => $itemid
 239          );
 240          if ($dbrec = $DB->get_record('backup_ids_temp', $record)) {
 241              self::$backupidsexist[$key] = $dbrec->id;
 242              self::$backupidscache[$key] = $dbrec;
 243              self::$backupidscachesize--;
 244              self::$backupidsexistsize--;
 245              return $dbrec;
 246          } else {
 247              return false;
 248          }
 249      }
 250  
 251      /**
 252       * Cache backup ids'
 253       *
 254       * @param int $restoreid id of backup
 255       * @param string $itemname name of the item
 256       * @param int $itemid id of item
 257       * @param array $extrarecord extra record which needs to be updated
 258       * @return void
 259       * @todo MDL-25290 replace static BACKUP_IDS_* with MUC code
 260       */
 261      protected static function set_backup_ids_cached($restoreid, $itemname, $itemid, $extrarecord) {
 262          global $DB;
 263  
 264          $key = "$itemid $itemname $restoreid";
 265  
 266          $record = array(
 267              'backupid' => $restoreid,
 268              'itemname' => $itemname,
 269              'itemid'   => $itemid,
 270          );
 271  
 272          // If record is not cached then add one.
 273          if (!isset(self::$backupidsexist[$key])) {
 274              // If we have this record in db, then just update this.
 275              if ($existingrecord = $DB->get_record('backup_ids_temp', $record)) {
 276                  self::$backupidsexist[$key] = $existingrecord->id;
 277                  self::$backupidsexistsize--;
 278                  self::update_backup_cached_record($record, $extrarecord, $key, $existingrecord);
 279              } else {
 280                  // Add new record to cache and db.
 281                  $recorddefault = array (
 282                      'newitemid' => 0,
 283                      'parentitemid' => null,
 284                      'info' => null);
 285                  $record = array_merge($record, $recorddefault, $extrarecord);
 286                  $record['id'] = $DB->insert_record('backup_ids_temp', $record);
 287                  self::$backupidsexist[$key] = $record['id'];
 288                  self::$backupidsexistsize--;
 289                  if (self::$backupidscachesize > 0) {
 290                      // Cache new records if we haven't got many yet.
 291                      self::$backupidscache[$key] = (object) $record;
 292                      self::$backupidscachesize--;
 293                  }
 294              }
 295          } else {
 296              self::update_backup_cached_record($record, $extrarecord, $key);
 297          }
 298      }
 299  
 300      /**
 301       * Updates existing backup record
 302       *
 303       * @param array $record record which needs to be updated
 304       * @param array $extrarecord extra record which needs to be updated
 305       * @param string $key unique key which is used to identify cached record
 306       * @param stdClass $existingrecord (optional) existing record
 307       */
 308      protected static function update_backup_cached_record($record, $extrarecord, $key, $existingrecord = null) {
 309          global $DB;
 310          // Update only if extrarecord is not empty.
 311          if (!empty($extrarecord)) {
 312              $extrarecord['id'] = self::$backupidsexist[$key];
 313              $DB->update_record('backup_ids_temp', $extrarecord);
 314              // Update existing cache or add new record to cache.
 315              if (isset(self::$backupidscache[$key])) {
 316                  $record = array_merge((array)self::$backupidscache[$key], $extrarecord);
 317                  self::$backupidscache[$key] = (object) $record;
 318              } else if (self::$backupidscachesize > 0) {
 319                  if ($existingrecord) {
 320                      self::$backupidscache[$key] = $existingrecord;
 321                  } else {
 322                      // Retrive record from database and cache updated records.
 323                      self::$backupidscache[$key] = $DB->get_record('backup_ids_temp', $record);
 324                  }
 325                  $record = array_merge((array)self::$backupidscache[$key], $extrarecord);
 326                  self::$backupidscache[$key] = (object) $record;
 327                  self::$backupidscachesize--;
 328              }
 329          }
 330      }
 331  
 332      /**
 333       * Reset the ids caches completely
 334       *
 335       * Any destructive operation (partial delete, truncate, drop or recreate) performed
 336       * with the backup_ids table must cause the backup_ids caches to be
 337       * invalidated by calling this method. See MDL-33630.
 338       *
 339       * Note that right now, the only operation of that type is the recreation
 340       * (drop & restore) of the table that may happen once the prechecks have ended. All
 341       * the rest of operations are always routed via {@link set_backup_ids_record()}, 1 by 1,
 342       * keeping the caches on sync.
 343       *
 344       * @todo MDL-25290 static should be replaced with MUC code.
 345       */
 346      public static function reset_backup_ids_cached() {
 347          // Reset the ids cache.
 348          $cachetoadd = count(self::$backupidscache);
 349          self::$backupidscache = array();
 350          self::$backupidscachesize = self::$backupidscachesize + $cachetoadd;
 351          // Reset the exists cache.
 352          $existstoadd = count(self::$backupidsexist);
 353          self::$backupidsexist = array();
 354          self::$backupidsexistsize = self::$backupidsexistsize + $existstoadd;
 355      }
 356  
 357      /**
 358       * Given one role, as loaded from XML, perform the best possible matching against the assignable
 359       * roles, using different fallback alternatives (shortname, archetype, editingteacher => teacher, defaultcourseroleid)
 360       * returning the id of the best matching role or 0 if no match is found
 361       */
 362      protected static function get_best_assignable_role($role, $courseid, $userid, $samesite) {
 363          global $CFG, $DB;
 364  
 365          // Gather various information about roles
 366          $coursectx = context_course::instance($courseid);
 367          $assignablerolesshortname = get_assignable_roles($coursectx, ROLENAME_SHORT, false, $userid);
 368  
 369          // Note: under 1.9 we had one function restore_samerole() that performed one complete
 370          // matching of roles (all caps) and if match was found the mapping was availabe bypassing
 371          // any assignable_roles() security. IMO that was wrong and we must not allow such
 372          // mappings anymore. So we have left that matching strategy out in 2.0
 373  
 374          // Empty assignable roles, mean no match possible
 375          if (empty($assignablerolesshortname)) {
 376              return 0;
 377          }
 378  
 379          // Match by shortname
 380          if ($match = array_search($role->shortname, $assignablerolesshortname)) {
 381              return $match;
 382          }
 383  
 384          // Match by archetype
 385          list($in_sql, $in_params) = $DB->get_in_or_equal(array_keys($assignablerolesshortname));
 386          $params = array_merge(array($role->archetype), $in_params);
 387          if ($rec = $DB->get_record_select('role', "archetype = ? AND id $in_sql", $params, 'id', IGNORE_MULTIPLE)) {
 388              return $rec->id;
 389          }
 390  
 391          // Match editingteacher to teacher (happens a lot, from 1.9)
 392          if ($role->shortname == 'editingteacher' && in_array('teacher', $assignablerolesshortname)) {
 393              return array_search('teacher', $assignablerolesshortname);
 394          }
 395  
 396          // No match, return 0
 397          return 0;
 398      }
 399  
 400  
 401      /**
 402       * Process the loaded roles, looking for their best mapping or skipping
 403       * Any error will cause exception. Note this is one wrapper over
 404       * precheck_included_roles, that contains all the logic, but returns
 405       * errors/warnings instead and is executed as part of the restore prechecks
 406       */
 407       public static function process_included_roles($restoreid, $courseid, $userid, $samesite, $rolemappings) {
 408          global $DB;
 409  
 410          // Just let precheck_included_roles() to do all the hard work
 411          $problems = self::precheck_included_roles($restoreid, $courseid, $userid, $samesite, $rolemappings);
 412  
 413          // With problems of type error, throw exception, shouldn't happen if prechecks executed
 414          if (array_key_exists('errors', $problems)) {
 415              throw new restore_dbops_exception('restore_problems_processing_roles', null, implode(', ', $problems['errors']));
 416          }
 417      }
 418  
 419      /**
 420       * Load the needed users.xml file to backup_ids table for future reference
 421       *
 422       * @param string $restoreid Restore id
 423       * @param string $usersfile File path
 424       * @param \core\progress\base $progress Progress tracker
 425       */
 426      public static function load_users_to_tempids($restoreid, $usersfile,
 427              \core\progress\base $progress = null) {
 428  
 429          if (!file_exists($usersfile)) { // Shouldn't happen ever, but...
 430              throw new backup_helper_exception('missing_users_xml_file', $usersfile);
 431          }
 432  
 433          // Set up progress tracking (indeterminate).
 434          if (!$progress) {
 435              $progress = new \core\progress\none();
 436          }
 437          $progress->start_progress('Loading users into temporary table');
 438  
 439          // Let's parse, custom processor will do its work, sending info to DB
 440          $xmlparser = new progressive_parser();
 441          $xmlparser->set_file($usersfile);
 442          $xmlprocessor = new restore_users_parser_processor($restoreid);
 443          $xmlparser->set_processor($xmlprocessor);
 444          $xmlparser->set_progress($progress);
 445          $xmlparser->process();
 446  
 447          // Finish progress.
 448          $progress->end_progress();
 449      }
 450  
 451      /**
 452       * Load the needed questions.xml file to backup_ids table for future reference
 453       */
 454      public static function load_categories_and_questions_to_tempids($restoreid, $questionsfile) {
 455  
 456          if (!file_exists($questionsfile)) { // Shouldn't happen ever, but...
 457              throw new backup_helper_exception('missing_questions_xml_file', $questionsfile);
 458          }
 459          // Let's parse, custom processor will do its work, sending info to DB
 460          $xmlparser = new progressive_parser();
 461          $xmlparser->set_file($questionsfile);
 462          $xmlprocessor = new restore_questions_parser_processor($restoreid);
 463          $xmlparser->set_processor($xmlprocessor);
 464          $xmlparser->process();
 465      }
 466  
 467      /**
 468       * Check all the included categories and questions, deciding the action to perform
 469       * for each one (mapping / creation) and returning one array of problems in case
 470       * something is wrong.
 471       *
 472       * There are some basic rules that the method below will always try to enforce:
 473       *
 474       * Rule1: Targets will be, always, calculated for *whole* question banks (a.k.a. contexid source),
 475       *     so, given 2 question categories belonging to the same bank, their target bank will be
 476       *     always the same. If not, we can be incurring into "fragmentation", leading to random/cloze
 477       *     problems (qtypes having "child" questions).
 478       *
 479       * Rule2: The 'moodle/question:managecategory' and 'moodle/question:add' capabilities will be
 480       *     checked before creating any category/question respectively and, if the cap is not allowed
 481       *     into upper contexts (system, coursecat)) but in lower ones (course), the *whole* question bank
 482       *     will be created there.
 483       *
 484       * Rule3: Coursecat question banks not existing in the target site will be created as course
 485       *     (lower ctx) question banks, never as "guessed" coursecat question banks base on depth or so.
 486       *
 487       * Rule4: System question banks will be created at system context if user has perms to do so. Else they
 488       *     will created as course (lower ctx) question banks (similary to rule3). In other words, course ctx
 489       *     if always a fallback for system and coursecat question banks.
 490       *
 491       * Also, there are some notes to clarify the scope of this method:
 492       *
 493       * Note1: This method won't create any question category nor question at all. It simply will calculate
 494       *     which actions (create/map) must be performed for each element and where, validating that all those
 495       *     actions are doable by the user executing the restore operation. Any problem found will be
 496       *     returned in the problems array, causing the restore process to stop with error.
 497       *
 498       * Note2: To decide if one question bank (all its question categories and questions) is going to be remapped,
 499       *     then all the categories and questions must exist in the same target bank. If able to do so, missing
 500       *     qcats and qs will be created (rule2). But if, at the end, something is missing, the whole question bank
 501       *     will be recreated at course ctx (rule1), no matter if that duplicates some categories/questions.
 502       *
 503       * Note3: We'll be using the newitemid column in the temp_ids table to store the action to be performed
 504       *     with each question category and question. newitemid = 0 means the qcat/q needs to be created and
 505       *     any other value means the qcat/q is mapped. Also, for qcats, parentitemid will contain the target
 506       *     context where the categories have to be created (but for module contexts where we'll keep the old
 507       *     one until the activity is created)
 508       *
 509       * Note4: All these "actions" will be "executed" later by {@link restore_create_categories_and_questions}
 510       */
 511      public static function precheck_categories_and_questions($restoreid, $courseid, $userid, $samesite) {
 512  
 513          $problems = array();
 514  
 515          // TODO: Check all qs, looking their qtypes are restorable
 516  
 517          // Precheck all qcats and qs looking for target contexts / warnings / errors
 518          list($syserr, $syswarn) = self::prechek_precheck_qbanks_by_level($restoreid, $courseid, $userid, $samesite, CONTEXT_SYSTEM);
 519          list($caterr, $catwarn) = self::prechek_precheck_qbanks_by_level($restoreid, $courseid, $userid, $samesite, CONTEXT_COURSECAT);
 520          list($couerr, $couwarn) = self::prechek_precheck_qbanks_by_level($restoreid, $courseid, $userid, $samesite, CONTEXT_COURSE);
 521          list($moderr, $modwarn) = self::prechek_precheck_qbanks_by_level($restoreid, $courseid, $userid, $samesite, CONTEXT_MODULE);
 522  
 523          // Acummulate and handle errors and warnings
 524          $errors   = array_merge($syserr, $caterr, $couerr, $moderr);
 525          $warnings = array_merge($syswarn, $catwarn, $couwarn, $modwarn);
 526          if (!empty($errors)) {
 527              $problems['errors'] = $errors;
 528          }
 529          if (!empty($warnings)) {
 530              $problems['warnings'] = $warnings;
 531          }
 532          return $problems;
 533      }
 534  
 535      /**
 536       * This function will process all the question banks present in restore
 537       * at some contextlevel (from CONTEXT_SYSTEM to CONTEXT_MODULE), finding
 538       * the target contexts where each bank will be restored and returning
 539       * warnings/errors as needed.
 540       *
 541       * Some contextlevels (system, coursecat), will delegate process to
 542       * course level if any problem is found (lack of permissions, non-matching
 543       * target context...). Other contextlevels (course, module) will
 544       * cause return error if some problem is found.
 545       *
 546       * At the end, if no errors were found, all the categories in backup_temp_ids
 547       * will be pointing (parentitemid) to the target context where they must be
 548       * created later in the restore process.
 549       *
 550       * Note: at the time these prechecks are executed, activities haven't been
 551       * created yet so, for CONTEXT_MODULE banks, we keep the old contextid
 552       * in the parentitemid field. Once the activity (and its context) has been
 553       * created, we'll update that context in the required qcats
 554       *
 555       * Caller {@link precheck_categories_and_questions} will, simply, execute
 556       * this function for all the contextlevels, acting as a simple controller
 557       * of warnings and errors.
 558       *
 559       * The function returns 2 arrays, one containing errors and another containing
 560       * warnings. Both empty if no errors/warnings are found.
 561       *
 562       * @param int $restoreid The restore ID
 563       * @param int $courseid The ID of the course
 564       * @param int $userid The id of the user doing the restore
 565       * @param bool $samesite True if restore is to same site
 566       * @param int $contextlevel (CONTEXT_SYSTEM, etc.)
 567       * @return array A separate list of all error and warnings detected
 568       */
 569      public static function prechek_precheck_qbanks_by_level($restoreid, $courseid, $userid, $samesite, $contextlevel) {
 570          global $DB;
 571  
 572          // To return any errors and warnings found
 573          $errors   = array();
 574          $warnings = array();
 575  
 576          // Specify which fallbacks must be performed
 577          $fallbacks = array(
 578              CONTEXT_SYSTEM => CONTEXT_COURSE,
 579              CONTEXT_COURSECAT => CONTEXT_COURSE);
 580  
 581          /** @var restore_controller $rc */
 582          $rc = restore_controller_dbops::load_controller($restoreid);
 583          $plan = $rc->get_plan();
 584          $after35 = $plan->backup_release_compare('3.5', '>=') && $plan->backup_version_compare(20180205, '>');
 585          $rc->destroy(); // Always need to destroy.
 586  
 587          // For any contextlevel, follow this process logic:
 588          //
 589          // 0) Iterate over each context (qbank)
 590          // 1) Iterate over each qcat in the context, matching by stamp for the found target context
 591          //     2a) No match, check if user can create qcat and q
 592          //         3a) User can, mark the qcat and all dependent qs to be created in that target context
 593          //         3b) User cannot, check if we are in some contextlevel with fallback
 594          //             4a) There is fallback, move ALL the qcats to fallback, warn. End qcat loop
 595          //             4b) No fallback, error. End qcat loop.
 596          //     2b) Match, mark qcat to be mapped and iterate over each q, matching by stamp and version
 597          //         5a) No match, check if user can add q
 598          //             6a) User can, mark the q to be created
 599          //             6b) User cannot, check if we are in some contextlevel with fallback
 600          //                 7a) There is fallback, move ALL the qcats to fallback, warn. End qcat loop
 601          //                 7b) No fallback, error. End qcat loop
 602          //         5b) Random question, must always create new.
 603          //         5c) Match, mark q to be mapped
 604          // 8) Check if backup is from Moodle >= 3.5 and error if more than one top-level category in the context.
 605  
 606          // Get all the contexts (question banks) in restore for the given contextlevel
 607          $contexts = self::restore_get_question_banks($restoreid, $contextlevel);
 608  
 609          // 0) Iterate over each context (qbank)
 610          foreach ($contexts as $contextid => $contextlevel) {
 611              // Init some perms
 612              $canmanagecategory = false;
 613              $canadd            = false;
 614              // Top-level category counter.
 615              $topcats = 0;
 616              // get categories in context (bank)
 617              $categories = self::restore_get_question_categories($restoreid, $contextid, $contextlevel);
 618  
 619              // cache permissions if $targetcontext is found
 620              if ($targetcontext = self::restore_find_best_target_context($categories, $courseid, $contextlevel)) {
 621                  $canmanagecategory = has_capability('moodle/question:managecategory', $targetcontext, $userid);
 622                  $canadd            = has_capability('moodle/question:add', $targetcontext, $userid);
 623              }
 624              // 1) Iterate over each qcat in the context, matching by stamp for the found target context
 625              foreach ($categories as $category) {
 626                  if ($category->parent == 0) {
 627                      $topcats++;
 628                  }
 629  
 630                  $matchcat = false;
 631                  if ($targetcontext) {
 632                      $matchcat = $DB->get_record('question_categories', array(
 633                                      'contextid' => $targetcontext->id,
 634                                      'stamp' => $category->stamp));
 635                  }
 636                  // 2a) No match, check if user can create qcat and q
 637                  if (!$matchcat) {
 638                      // 3a) User can, mark the qcat and all dependent qs to be created in that target context
 639                      if ($canmanagecategory && $canadd) {
 640                          // Set parentitemid to targetcontext, BUT for CONTEXT_MODULE categories, where
 641                          // we keep the source contextid unmodified (for easier matching later when the
 642                          // activities are created)
 643                          $parentitemid = $targetcontext->id;
 644                          if ($contextlevel == CONTEXT_MODULE) {
 645                              $parentitemid = null; // null means "not modify" a.k.a. leave original contextid
 646                          }
 647                          self::set_backup_ids_record($restoreid, 'question_category', $category->id, 0, $parentitemid);
 648                          // Nothing else to mark, newitemid = 0 means create
 649  
 650                      // 3b) User cannot, check if we are in some contextlevel with fallback
 651                      } else {
 652                          // 4a) There is fallback, move ALL the qcats to fallback, warn. End qcat loop
 653                          if (array_key_exists($contextlevel, $fallbacks)) {
 654                              foreach ($categories as $movedcat) {
 655                                  $movedcat->contextlevel = $fallbacks[$contextlevel];
 656                                  self::set_backup_ids_record($restoreid, 'question_category', $movedcat->id, 0, $contextid, $movedcat);
 657                                  // Warn about the performed fallback
 658                                  $warnings[] = get_string('qcategory2coursefallback', 'backup', $movedcat);
 659                              }
 660  
 661                          // 4b) No fallback, error. End qcat loop.
 662                          } else {
 663                              $errors[] = get_string('qcategorycannotberestored', 'backup', $category);
 664                          }
 665                          break; // out from qcat loop (both 4a and 4b), we have decided about ALL categories in context (bank)
 666                      }
 667  
 668                  // 2b) Match, mark qcat to be mapped and iterate over each q, matching by stamp and version
 669                  } else {
 670                      self::set_backup_ids_record($restoreid, 'question_category', $category->id, $matchcat->id, $targetcontext->id);
 671                      $questions = self::restore_get_questions($restoreid, $category->id);
 672  
 673                      // Collect all the questions for this category into memory so we only talk to the DB once.
 674                      $questioncache = $DB->get_records_sql_menu('SELECT q.id,
 675                                                                         q.stamp
 676                                                                    FROM {question} q
 677                                                                    JOIN {question_versions} qv
 678                                                                      ON qv.questionid = q.id
 679                                                                    JOIN {question_bank_entries} qbe
 680                                                                      ON qbe.id = qv.questionbankentryid
 681                                                                    JOIN {question_categories} qc
 682                                                                      ON qc.id = qbe.questioncategoryid
 683                                                                   WHERE qc.id = ?', array($matchcat->id));
 684  
 685                      foreach ($questions as $question) {
 686                          if (isset($questioncache[$question->stamp." ".$question->version])) {
 687                              $matchqid = $questioncache[$question->stamp." ".$question->version];
 688                          } else {
 689                              $matchqid = false;
 690                          }
 691                          // 5a) No match, check if user can add q
 692                          if (!$matchqid) {
 693                              // 6a) User can, mark the q to be created
 694                              if ($canadd) {
 695                                  // Nothing to mark, newitemid means create
 696  
 697                               // 6b) User cannot, check if we are in some contextlevel with fallback
 698                              } else {
 699                                  // 7a) There is fallback, move ALL the qcats to fallback, warn. End qcat loo
 700                                  if (array_key_exists($contextlevel, $fallbacks)) {
 701                                      foreach ($categories as $movedcat) {
 702                                          $movedcat->contextlevel = $fallbacks[$contextlevel];
 703                                          self::set_backup_ids_record($restoreid, 'question_category', $movedcat->id, 0, $contextid, $movedcat);
 704                                          // Warn about the performed fallback
 705                                          $warnings[] = get_string('question2coursefallback', 'backup', $movedcat);
 706                                      }
 707  
 708                                  // 7b) No fallback, error. End qcat loop
 709                                  } else {
 710                                      $errors[] = get_string('questioncannotberestored', 'backup', $question);
 711                                  }
 712                                  break 2; // out from qcat loop (both 7a and 7b), we have decided about ALL categories in context (bank)
 713                              }
 714  
 715                          // 5b) Random questions must always be newly created.
 716                          } else if ($question->qtype == 'random') {
 717                              // Nothing to mark, newitemid means create
 718  
 719                          // 5c) Match, mark q to be mapped.
 720                          } else {
 721                              self::set_backup_ids_record($restoreid, 'question', $question->id, $matchqid);
 722                          }
 723                      }
 724                  }
 725              }
 726  
 727              // 8) Check if backup is made on Moodle >= 3.5 and there are more than one top-level category in the context.
 728              if ($after35 && $topcats > 1) {
 729                  $errors[] = get_string('restoremultipletopcats', 'question', $contextid);
 730              }
 731  
 732          }
 733  
 734          return array($errors, $warnings);
 735      }
 736  
 737      /**
 738       * Return one array of contextid => contextlevel pairs
 739       * of question banks to be checked for one given restore operation
 740       * ordered from CONTEXT_SYSTEM downto CONTEXT_MODULE
 741       * If contextlevel is specified, then only banks corresponding to
 742       * that level are returned
 743       */
 744      public static function restore_get_question_banks($restoreid, $contextlevel = null) {
 745          global $DB;
 746  
 747          $results = array();
 748          $qcats = $DB->get_recordset_sql("SELECT itemid, parentitemid AS contextid, info
 749                                           FROM {backup_ids_temp}
 750                                         WHERE backupid = ?
 751                                           AND itemname = 'question_category'", array($restoreid));
 752          foreach ($qcats as $qcat) {
 753              // If this qcat context haven't been acummulated yet, do that
 754              if (!isset($results[$qcat->contextid])) {
 755                  $info = backup_controller_dbops::decode_backup_temp_info($qcat->info);
 756                  // Filter by contextlevel if necessary
 757                  if (is_null($contextlevel) || $contextlevel == $info->contextlevel) {
 758                      $results[$qcat->contextid] = $info->contextlevel;
 759                  }
 760              }
 761          }
 762          $qcats->close();
 763          // Sort by value (contextlevel from CONTEXT_SYSTEM downto CONTEXT_MODULE)
 764          asort($results);
 765          return $results;
 766      }
 767  
 768      /**
 769       * Return one array of question_category records for
 770       * a given restore operation and one restore context (question bank)
 771       *
 772       * @param string $restoreid Unique identifier of the restore operation being performed.
 773       * @param int $contextid Context id we want question categories to be returned.
 774       * @param int $contextlevel Context level we want to restrict the returned categories.
 775       * @return array Question categories for the given context id and level.
 776       */
 777      public static function restore_get_question_categories($restoreid, $contextid, $contextlevel) {
 778          global $DB;
 779  
 780          $results = array();
 781          $qcats = $DB->get_recordset_sql("SELECT itemid, info
 782                                           FROM {backup_ids_temp}
 783                                          WHERE backupid = ?
 784                                            AND itemname = 'question_category'
 785                                            AND parentitemid = ?", array($restoreid, $contextid));
 786          foreach ($qcats as $qcat) {
 787              $result = backup_controller_dbops::decode_backup_temp_info($qcat->info);
 788              // Filter out found categories that belong to another context level.
 789              // (this can happen when a higher level category becomes remapped to
 790              // a context id that, by coincidence, matches a context id of another
 791              // category at lower level). See MDL-72950 for more info.
 792              if ($result->contextlevel == $contextlevel) {
 793                  $results[$qcat->itemid] = $result;
 794              }
 795          }
 796          $qcats->close();
 797  
 798          return $results;
 799      }
 800  
 801      /**
 802       * Calculates the best context found to restore one collection of qcats,
 803       * al them belonging to the same context (question bank), returning the
 804       * target context found (object) or false
 805       */
 806      public static function restore_find_best_target_context($categories, $courseid, $contextlevel) {
 807          global $DB;
 808  
 809          $targetcontext = false;
 810  
 811          // Depending of $contextlevel, we perform different actions
 812          switch ($contextlevel) {
 813               // For system is easy, the best context is the system context
 814               case CONTEXT_SYSTEM:
 815                   $targetcontext = context_system::instance();
 816                   break;
 817  
 818               // For coursecat, we are going to look for stamps in all the
 819               // course categories between CONTEXT_SYSTEM and CONTEXT_COURSE
 820               // (i.e. in all the course categories in the path)
 821               //
 822               // And only will return one "best" target context if all the
 823               // matches belong to ONE and ONLY ONE context. If multiple
 824               // matches are found, that means that there is some annoying
 825               // qbank "fragmentation" in the categories, so we'll fallback
 826               // to create the qbank at course level
 827               case CONTEXT_COURSECAT:
 828                   // Build the array of stamps we are going to match
 829                   $stamps = array();
 830                   foreach ($categories as $category) {
 831                       $stamps[] = $category->stamp;
 832                   }
 833                   $contexts = array();
 834                   // Build the array of contexts we are going to look
 835                   $systemctx = context_system::instance();
 836                   $coursectx = context_course::instance($courseid);
 837                   $parentctxs = $coursectx->get_parent_context_ids();
 838                   foreach ($parentctxs as $parentctx) {
 839                       // Exclude system context
 840                       if ($parentctx == $systemctx->id) {
 841                           continue;
 842                       }
 843                       $contexts[] = $parentctx;
 844                   }
 845                   if (!empty($stamps) && !empty($contexts)) {
 846                       // Prepare the query
 847                       list($stamp_sql, $stamp_params) = $DB->get_in_or_equal($stamps);
 848                       list($context_sql, $context_params) = $DB->get_in_or_equal($contexts);
 849                       $sql = "SELECT DISTINCT contextid
 850                                 FROM {question_categories}
 851                                WHERE stamp $stamp_sql
 852                                  AND contextid $context_sql";
 853                       $params = array_merge($stamp_params, $context_params);
 854                       $matchingcontexts = $DB->get_records_sql($sql, $params);
 855                       // Only if ONE and ONLY ONE context is found, use it as valid target
 856                       if (count($matchingcontexts) == 1) {
 857                           $targetcontext = context::instance_by_id(reset($matchingcontexts)->contextid);
 858                       }
 859                   }
 860                   break;
 861  
 862               // For course is easy, the best context is the course context
 863               case CONTEXT_COURSE:
 864                   $targetcontext = context_course::instance($courseid);
 865                   break;
 866  
 867               // For module is easy, there is not best context, as far as the
 868               // activity hasn't been created yet. So we return context course
 869               // for them, so permission checks and friends will work. Note this
 870               // case is handled by {@link prechek_precheck_qbanks_by_level}
 871               // in an special way
 872               case CONTEXT_MODULE:
 873                   $targetcontext = context_course::instance($courseid);
 874                   break;
 875          }
 876          return $targetcontext;
 877      }
 878  
 879      /**
 880       * Return one array of question records for
 881       * a given restore operation and one question category
 882       */
 883      public static function restore_get_questions($restoreid, $qcatid) {
 884          global $DB;
 885  
 886          $results = array();
 887          $qs = $DB->get_recordset_sql("SELECT itemid, info
 888                                        FROM {backup_ids_temp}
 889                                       WHERE backupid = ?
 890                                         AND itemname = 'question'
 891                                         AND parentitemid = ?", array($restoreid, $qcatid));
 892          foreach ($qs as $q) {
 893              $results[$q->itemid] = backup_controller_dbops::decode_backup_temp_info($q->info);
 894          }
 895          $qs->close();
 896          return $results;
 897      }
 898  
 899      /**
 900       * Given one component/filearea/context and
 901       * optionally one source itemname to match itemids
 902       * put the corresponding files in the pool
 903       *
 904       * If you specify a progress reporter, it will get called once per file with
 905       * indeterminate progress.
 906       *
 907       * @param string $basepath the full path to the root of unzipped backup file
 908       * @param string $restoreid the restore job's identification
 909       * @param string $component
 910       * @param string $filearea
 911       * @param int $oldcontextid
 912       * @param int $dfltuserid default $file->user if the old one can't be mapped
 913       * @param string|null $itemname
 914       * @param int|null $olditemid
 915       * @param int|null $forcenewcontextid explicit value for the new contextid (skip mapping)
 916       * @param bool $skipparentitemidctxmatch
 917       * @param \core\progress\base $progress Optional progress reporter
 918       * @return array of result object
 919       */
 920      public static function send_files_to_pool($basepath, $restoreid, $component, $filearea,
 921              $oldcontextid, $dfltuserid, $itemname = null, $olditemid = null,
 922              $forcenewcontextid = null, $skipparentitemidctxmatch = false,
 923              \core\progress\base $progress = null) {
 924          global $DB, $CFG;
 925  
 926          $backupinfo = backup_general_helper::get_backup_information(basename($basepath));
 927          $includesfiles = $backupinfo->include_files;
 928  
 929          $results = array();
 930  
 931          if ($forcenewcontextid) {
 932              // Some components can have "forced" new contexts (example: questions can end belonging to non-standard context mappings,
 933              // with questions originally at system/coursecat context in source being restored to course context in target). So we need
 934              // to be able to force the new contextid
 935              $newcontextid = $forcenewcontextid;
 936          } else {
 937              // Get new context, must exist or this will fail
 938              $newcontextrecord = self::get_backup_ids_record($restoreid, 'context', $oldcontextid);
 939              if (!$newcontextrecord || !$newcontextrecord->newitemid) {
 940                  throw new restore_dbops_exception('unknown_context_mapping', $oldcontextid);
 941              }
 942              $newcontextid = $newcontextrecord->newitemid;
 943          }
 944  
 945          // Sometimes it's possible to have not the oldcontextids stored into backup_ids_temp->parentitemid
 946          // columns (because we have used them to store other information). This happens usually with
 947          // all the question related backup_ids_temp records. In that case, it's safe to ignore that
 948          // matching as far as we are always restoring for well known oldcontexts and olditemids
 949          $parentitemctxmatchsql = ' AND i.parentitemid = f.contextid ';
 950          if ($skipparentitemidctxmatch) {
 951              $parentitemctxmatchsql = '';
 952          }
 953  
 954          // Important: remember how files have been loaded to backup_files_temp
 955          //   - info: contains the whole original object (times, names...)
 956          //   (all them being original ids as loaded from xml)
 957  
 958          // itemname = null, we are going to match only by context, no need to use itemid (all them are 0)
 959          if ($itemname == null) {
 960              $sql = "SELECT id AS bftid, contextid, component, filearea, itemid, itemid AS newitemid, info
 961                        FROM {backup_files_temp}
 962                       WHERE backupid = ?
 963                         AND contextid = ?
 964                         AND component = ?
 965                         AND filearea  = ?";
 966              $params = array($restoreid, $oldcontextid, $component, $filearea);
 967  
 968          // itemname not null, going to join with backup_ids to perform the old-new mapping of itemids
 969          } else {
 970              $sql = "SELECT f.id AS bftid, f.contextid, f.component, f.filearea, f.itemid, i.newitemid, f.info
 971                        FROM {backup_files_temp} f
 972                        JOIN {backup_ids_temp} i ON i.backupid = f.backupid
 973                                                $parentitemctxmatchsql
 974                                                AND i.itemid = f.itemid
 975                       WHERE f.backupid = ?
 976                         AND f.contextid = ?
 977                         AND f.component = ?
 978                         AND f.filearea = ?
 979                         AND i.itemname = ?";
 980              $params = array($restoreid, $oldcontextid, $component, $filearea, $itemname);
 981              if ($olditemid !== null) { // Just process ONE olditemid intead of the whole itemname
 982                  $sql .= ' AND i.itemid = ?';
 983                  $params[] = $olditemid;
 984              }
 985          }
 986  
 987          $fs = get_file_storage();         // Get moodle file storage
 988          $basepath = $basepath . '/files/';// Get backup file pool base
 989          // Report progress before query.
 990          if ($progress) {
 991              $progress->progress();
 992          }
 993          $rs = $DB->get_recordset_sql($sql, $params);
 994          foreach ($rs as $rec) {
 995              // Report progress each time around loop.
 996              if ($progress) {
 997                  $progress->progress();
 998              }
 999  
1000              $file = (object)backup_controller_dbops::decode_backup_temp_info($rec->info);
1001  
1002              // ignore root dirs (they are created automatically)
1003              if ($file->filepath == '/' && $file->filename == '.') {
1004                  continue;
1005              }
1006  
1007              // set the best possible user
1008              $mappeduser = self::get_backup_ids_record($restoreid, 'user', $file->userid);
1009              $mappeduserid = !empty($mappeduser) ? $mappeduser->newitemid : $dfltuserid;
1010  
1011              // dir found (and not root one), let's create it
1012              if ($file->filename == '.') {
1013                  $fs->create_directory($newcontextid, $component, $filearea, $rec->newitemid, $file->filepath, $mappeduserid);
1014                  continue;
1015              }
1016  
1017              // Updated the times of the new record.
1018              // The file record should reflect when the file entered the system,
1019              // and when this record was created.
1020              $time = time();
1021  
1022              // The file record to restore.
1023              $file_record = array(
1024                  'contextid'    => $newcontextid,
1025                  'component'    => $component,
1026                  'filearea'     => $filearea,
1027                  'itemid'       => $rec->newitemid,
1028                  'filepath'     => $file->filepath,
1029                  'filename'     => $file->filename,
1030                  'timecreated'  => $time,
1031                  'timemodified' => $time,
1032                  'userid'       => $mappeduserid,
1033                  'source'       => $file->source,
1034                  'author'       => $file->author,
1035                  'license'      => $file->license,
1036                  'sortorder'    => $file->sortorder
1037              );
1038  
1039              if (empty($file->repositoryid)) {
1040                  // If contenthash is empty then gracefully skip adding file.
1041                  if (empty($file->contenthash)) {
1042                      $result = new stdClass();
1043                      $result->code = 'file_missing_in_backup';
1044                      $result->message = sprintf('missing file (%s) contenthash in backup for component %s', $file->filename, $component);
1045                      $result->level = backup::LOG_WARNING;
1046                      $results[] = $result;
1047                      continue;
1048                  }
1049                  // this is a regular file, it must be present in the backup pool
1050                  $backuppath = $basepath . backup_file_manager::get_backup_content_file_location($file->contenthash);
1051  
1052                  // Some file types do not include the files as they should already be
1053                  // present. We still need to create entries into the files table.
1054                  if ($includesfiles) {
1055                      // The file is not found in the backup.
1056                      if (!file_exists($backuppath)) {
1057                          $results[] = self::get_missing_file_result($file);
1058                          continue;
1059                      }
1060  
1061                      // create the file in the filepool if it does not exist yet
1062                      if (!$fs->file_exists($newcontextid, $component, $filearea, $rec->newitemid, $file->filepath, $file->filename)) {
1063  
1064                          // If no license found, use default.
1065                          if ($file->license == null){
1066                              $file->license = $CFG->sitedefaultlicense;
1067                          }
1068  
1069                          $fs->create_file_from_pathname($file_record, $backuppath);
1070                      }
1071                  } else {
1072                      // This backup does not include the files - they should be available in moodle filestorage already.
1073  
1074                      // Create the file in the filepool if it does not exist yet.
1075                      if (!$fs->file_exists($newcontextid, $component, $filearea, $rec->newitemid, $file->filepath, $file->filename)) {
1076  
1077                          // Even if a file has been deleted since the backup was made, the file metadata may remain in the
1078                          // files table, and the file will not yet have been moved to the trashdir. e.g. a draft file version.
1079                          // Try to recover from file table first.
1080                          if ($foundfiles = $DB->get_records('files', array('contenthash' => $file->contenthash), '', '*', 0, 1)) {
1081                              // Only grab one of the foundfiles - the file content should be the same for all entries.
1082                              $foundfile = reset($foundfiles);
1083                              $fs->create_file_from_storedfile($file_record, $foundfile->id);
1084                          } else {
1085                              $filesystem = $fs->get_file_system();
1086                              $restorefile = $file;
1087                              $restorefile->contextid = $newcontextid;
1088                              $restorefile->itemid = $rec->newitemid;
1089                              $storedfile = new stored_file($fs, $restorefile);
1090  
1091                              // Ok, let's try recover this file.
1092                              // 1. We check if the file can be fetched locally without attempting to fetch
1093                              //    from the trash.
1094                              // 2. We check if we can get the remote filepath for the specified stored file.
1095                              // 3. We check if the file can be fetched from the trash.
1096                              // 4. All failed, say we couldn't find it.
1097                              if ($filesystem->is_file_readable_locally_by_storedfile($storedfile)) {
1098                                  $localpath = $filesystem->get_local_path_from_storedfile($storedfile);
1099                                  $fs->create_file_from_pathname($file, $localpath);
1100                              } else if ($filesystem->is_file_readable_remotely_by_storedfile($storedfile)) {
1101                                  $remotepath = $filesystem->get_remote_path_from_storedfile($storedfile);
1102                                  $fs->create_file_from_pathname($file, $remotepath);
1103                              } else if ($filesystem->is_file_readable_locally_by_storedfile($storedfile, true)) {
1104                                  $localpath = $filesystem->get_local_path_from_storedfile($storedfile, true);
1105                                  $fs->create_file_from_pathname($file, $localpath);
1106                              } else {
1107                                  // A matching file was not found.
1108                                  $results[] = self::get_missing_file_result($file);
1109                                  continue;
1110                              }
1111                          }
1112                      }
1113                  }
1114  
1115                  // store the the new contextid and the new itemid in case we need to remap
1116                  // references to this file later
1117                  $DB->update_record('backup_files_temp', array(
1118                      'id' => $rec->bftid,
1119                      'newcontextid' => $newcontextid,
1120                      'newitemid' => $rec->newitemid), true);
1121  
1122              } else {
1123                  // this is an alias - we can't create it yet so we stash it in a temp
1124                  // table and will let the final task to deal with it
1125                  if (!$fs->file_exists($newcontextid, $component, $filearea, $rec->newitemid, $file->filepath, $file->filename)) {
1126                      $info = new stdClass();
1127                      // oldfile holds the raw information stored in MBZ (including reference-related info)
1128                      $info->oldfile = $file;
1129                      // newfile holds the info for the new file_record with the context, user and itemid mapped
1130                      $info->newfile = (object) $file_record;
1131  
1132                      restore_dbops::set_backup_ids_record($restoreid, 'file_aliases_queue', $file->id, 0, null, $info);
1133                  }
1134              }
1135          }
1136          $rs->close();
1137          return $results;
1138      }
1139  
1140      /**
1141       * Returns suitable entry to include in log when there is a missing file.
1142       *
1143       * @param stdClass $file File definition
1144       * @return stdClass Log entry
1145       */
1146      protected static function get_missing_file_result($file) {
1147          $result = new stdClass();
1148          $result->code = 'file_missing_in_backup';
1149          $result->message = 'Missing file in backup: ' . $file->filepath  . $file->filename .
1150                  ' (old context ' . $file->contextid . ', component ' . $file->component .
1151                  ', filearea ' . $file->filearea . ', old itemid ' . $file->itemid . ')';
1152          $result->level = backup::LOG_WARNING;
1153          return $result;
1154      }
1155  
1156      /**
1157       * Given one restoreid, create in DB all the users present
1158       * in backup_ids having newitemid = 0, as far as
1159       * precheck_included_users() have left them there
1160       * ready to be created. Also, annotate their newids
1161       * once created for later reference.
1162       *
1163       * This function will start and end a new progress section in the progress
1164       * object.
1165       *
1166       * @param string $basepath Base path of unzipped backup
1167       * @param string $restoreid Restore ID
1168       * @param int $userid Default userid for files
1169       * @param \core\progress\base $progress Object used for progress tracking
1170       */
1171      public static function create_included_users($basepath, $restoreid, $userid,
1172              \core\progress\base $progress) {
1173          global $CFG, $DB;
1174          require_once($CFG->dirroot.'/user/profile/lib.php');
1175          $progress->start_progress('Creating included users');
1176  
1177          $authcache = array(); // Cache to get some bits from authentication plugins
1178          $languages = get_string_manager()->get_list_of_translations(); // Get languages for quick search later
1179          $themes    = get_list_of_themes(); // Get themes for quick search later
1180  
1181          // Iterate over all the included users with newitemid = 0, have to create them
1182          $rs = $DB->get_recordset('backup_ids_temp', array('backupid' => $restoreid, 'itemname' => 'user', 'newitemid' => 0), '', 'itemid, parentitemid, info');
1183          foreach ($rs as $recuser) {
1184              $progress->progress();
1185              $user = (object)backup_controller_dbops::decode_backup_temp_info($recuser->info);
1186  
1187              // if user lang doesn't exist here, use site default
1188              if (!array_key_exists($user->lang, $languages)) {
1189                  $user->lang = get_newuser_language();
1190              }
1191  
1192              // if user theme isn't available on target site or they are disabled, reset theme
1193              if (!empty($user->theme)) {
1194                  if (empty($CFG->allowuserthemes) || !in_array($user->theme, $themes)) {
1195                      $user->theme = '';
1196                  }
1197              }
1198  
1199              // if user to be created has mnet auth and its mnethostid is $CFG->mnet_localhost_id
1200              // that's 100% impossible as own server cannot be accesed over mnet. Change auth to email/manual
1201              if ($user->auth == 'mnet' && $user->mnethostid == $CFG->mnet_localhost_id) {
1202                  // Respect registerauth
1203                  if ($CFG->registerauth == 'email') {
1204                      $user->auth = 'email';
1205                  } else {
1206                      $user->auth = 'manual';
1207                  }
1208              }
1209              unset($user->mnethosturl); // Not needed anymore
1210  
1211              // Disable pictures based on global setting
1212              if (!empty($CFG->disableuserimages)) {
1213                  $user->picture = 0;
1214              }
1215  
1216              // We need to analyse the AUTH field to recode it:
1217              //   - if the auth isn't enabled in target site, $CFG->registerauth will decide
1218              //   - finally, if the auth resulting isn't enabled, default to 'manual'
1219              if (!is_enabled_auth($user->auth)) {
1220                  if ($CFG->registerauth == 'email') {
1221                      $user->auth = 'email';
1222                  } else {
1223                      $user->auth = 'manual';
1224                  }
1225              }
1226              if (!is_enabled_auth($user->auth)) { // Final auth check verify, default to manual if not enabled
1227                  $user->auth = 'manual';
1228              }
1229  
1230              // Now that we know the auth method, for users to be created without pass
1231              // if password handling is internal and reset password is available
1232              // we set the password to "restored" (plain text), so the login process
1233              // will know how to handle that situation in order to allow the user to
1234              // recover the password. MDL-20846
1235              if (empty($user->password)) { // Only if restore comes without password
1236                  if (!array_key_exists($user->auth, $authcache)) { // Not in cache
1237                      $userauth = new stdClass();
1238                      $authplugin = get_auth_plugin($user->auth);
1239                      $userauth->preventpassindb = $authplugin->prevent_local_passwords();
1240                      $userauth->isinternal      = $authplugin->is_internal();
1241                      $userauth->canresetpwd     = $authplugin->can_reset_password();
1242                      $authcache[$user->auth] = $userauth;
1243                  } else {
1244                      $userauth = $authcache[$user->auth]; // Get from cache
1245                  }
1246  
1247                  // Most external plugins do not store passwords locally
1248                  if (!empty($userauth->preventpassindb)) {
1249                      $user->password = AUTH_PASSWORD_NOT_CACHED;
1250  
1251                  // If Moodle is responsible for storing/validating pwd and reset functionality is available, mark
1252                  } else if ($userauth->isinternal and $userauth->canresetpwd) {
1253                      $user->password = 'restored';
1254                  }
1255              }
1256  
1257              // Creating new user, we must reset the policyagreed always
1258              $user->policyagreed = 0;
1259  
1260              // Set time created if empty
1261              if (empty($user->timecreated)) {
1262                  $user->timecreated = time();
1263              }
1264  
1265              // Done, let's create the user and annotate its id
1266              $newuserid = $DB->insert_record('user', $user);
1267              self::set_backup_ids_record($restoreid, 'user', $recuser->itemid, $newuserid);
1268              // Let's create the user context and annotate it (we need it for sure at least for files)
1269              // but for deleted users that don't have a context anymore (MDL-30192). We are done for them
1270              // and nothing else (custom fields, prefs, tags, files...) will be created.
1271              if (empty($user->deleted)) {
1272                  $newuserctxid = $user->deleted ? 0 : context_user::instance($newuserid)->id;
1273                  self::set_backup_ids_record($restoreid, 'context', $recuser->parentitemid, $newuserctxid);
1274  
1275                  // Process custom fields
1276                  if (isset($user->custom_fields)) { // if present in backup
1277                      foreach($user->custom_fields['custom_field'] as $udata) {
1278                          $udata = (object)$udata;
1279                          // If the profile field has data and the profile shortname-datatype is defined in server
1280                          if ($udata->field_data) {
1281                              $field = profile_get_custom_field_data_by_shortname($udata->field_name);
1282                              if ($field && $field->datatype === $udata->field_type) {
1283                                  // Insert the user_custom_profile_field.
1284                                  $rec = new stdClass();
1285                                  $rec->userid  = $newuserid;
1286                                  $rec->fieldid = $field->id;
1287                                  $rec->data    = $udata->field_data;
1288                                  $DB->insert_record('user_info_data', $rec);
1289                              }
1290                          }
1291                      }
1292                  }
1293  
1294                  // Process tags
1295                  if (core_tag_tag::is_enabled('core', 'user') && isset($user->tags)) { // If enabled in server and present in backup.
1296                      $tags = array();
1297                      foreach($user->tags['tag'] as $usertag) {
1298                          $usertag = (object)$usertag;
1299                          $tags[] = $usertag->rawname;
1300                      }
1301                      core_tag_tag::set_item_tags('core', 'user', $newuserid,
1302                              context_user::instance($newuserid), $tags);
1303                  }
1304  
1305                  // Process preferences
1306                  if (isset($user->preferences)) { // if present in backup
1307                      foreach($user->preferences['preference'] as $preference) {
1308                          $preference = (object)$preference;
1309                          // Prepare the record and insert it
1310                          $preference->userid = $newuserid;
1311  
1312                          // Translate _loggedin / _loggedoff message user preferences to _enabled. (MDL-67853)
1313                          // This code cannot be removed.
1314                          if (preg_match('/message_provider_.*/', $preference->name)) {
1315                              $nameparts = explode('_', $preference->name);
1316                              $name = array_pop($nameparts);
1317  
1318                              if ($name == 'loggedin' || $name == 'loggedoff') {
1319                                  $preference->name = implode('_', $nameparts).'_enabled';
1320  
1321                                  $existingpreference = $DB->get_record('user_preferences',
1322                                      ['name' => $preference->name , 'userid' => $newuserid]);
1323                                  // Merge both values.
1324                                  if ($existingpreference) {
1325                                      $values = [];
1326  
1327                                      if (!empty($existingpreference->value) && $existingpreference->value != 'none') {
1328                                          $values = explode(',', $existingpreference->value);
1329                                      }
1330  
1331                                      if (!empty($preference->value) && $preference->value != 'none') {
1332                                          $values = array_merge(explode(',', $preference->value), $values);
1333                                          $values = array_unique($values);
1334                                      }
1335  
1336                                      $existingpreference->value = empty($values) ? 'none' : implode(',', $values);
1337  
1338                                      $DB->update_record('user_preferences', $existingpreference);
1339                                      continue;
1340                                  }
1341                              }
1342                          }
1343                          // End translating loggedin / loggedoff message user preferences.
1344  
1345                          $DB->insert_record('user_preferences', $preference);
1346                      }
1347                  }
1348                  // Special handling for htmleditor which was converted to a preference.
1349                  if (isset($user->htmleditor)) {
1350                      if ($user->htmleditor == 0) {
1351                          $preference = new stdClass();
1352                          $preference->userid = $newuserid;
1353                          $preference->name = 'htmleditor';
1354                          $preference->value = 'textarea';
1355                          $DB->insert_record('user_preferences', $preference);
1356                      }
1357                  }
1358  
1359                  // Create user files in pool (profile, icon, private) by context
1360                  restore_dbops::send_files_to_pool($basepath, $restoreid, 'user', 'icon',
1361                          $recuser->parentitemid, $userid, null, null, null, false, $progress);
1362                  restore_dbops::send_files_to_pool($basepath, $restoreid, 'user', 'profile',
1363                          $recuser->parentitemid, $userid, null, null, null, false, $progress);
1364              }
1365          }
1366          $rs->close();
1367          $progress->end_progress();
1368      }
1369  
1370      /**
1371      * Given one user object (from backup file), perform all the neccesary
1372      * checks is order to decide how that user will be handled on restore.
1373      *
1374      * Note the function requires $user->mnethostid to be already calculated
1375      * so it's caller responsibility to set it
1376      *
1377      * This function is used both by @restore_precheck_users() and
1378      * @restore_create_users() to get consistent results in both places
1379      *
1380      * It returns:
1381      *   - one user object (from DB), if match has been found and user will be remapped
1382      *   - boolean true if the user needs to be created
1383      *   - boolean false if some conflict happened and the user cannot be handled
1384      *
1385      * Each test is responsible for returning its results and interrupt
1386      * execution. At the end, boolean true (user needs to be created) will be
1387      * returned if no test has interrupted that.
1388      *
1389      * Here it's the logic applied, keep it updated:
1390      *
1391      *  If restoring users from same site backup:
1392      *      1A - Normal check: If match by id and username and mnethost  => ok, return target user
1393      *      1B - If restoring an 'anonymous' user (created via the 'Anonymize user information' option) try to find a
1394      *           match by username only => ok, return target user MDL-31484
1395      *      1C - Handle users deleted in DB and "alive" in backup file:
1396      *           If match by id and mnethost and user is deleted in DB and
1397      *           (match by username LIKE 'backup_email.%' or by non empty email = md5(username)) => ok, return target user
1398      *      1D - Handle users deleted in backup file and "alive" in DB:
1399      *           If match by id and mnethost and user is deleted in backup file
1400      *           and match by email = email_without_time(backup_email) => ok, return target user
1401      *      1E - Conflict: If match by username and mnethost and doesn't match by id => conflict, return false
1402      *      1F - None of the above, return true => User needs to be created
1403      *
1404      *  if restoring from another site backup (cannot match by id here, replace it by email/firstaccess combination):
1405      *      2A - Normal check:
1406      *           2A1 - If match by username and mnethost and (email or non-zero firstaccess) => ok, return target user
1407      *           2A2 - Exceptional handling (MDL-21912): Match "admin" username. Then, if import_general_duplicate_admin_allowed is
1408      *                 enabled, attempt to map the admin user to the user 'admin_[oldsiteid]' if it exists. If not,
1409      *                 the user 'admin_[oldsiteid]' will be created in precheck_included users
1410      *      2B - Handle users deleted in DB and "alive" in backup file:
1411      *           2B1 - If match by mnethost and user is deleted in DB and not empty email = md5(username) and
1412      *                 (username LIKE 'backup_email.%' or non-zero firstaccess) => ok, return target user
1413      *           2B2 - If match by mnethost and user is deleted in DB and
1414      *                 username LIKE 'backup_email.%' and non-zero firstaccess) => ok, return target user
1415      *                 (to cover situations were md5(username) wasn't implemented on delete we requiere both)
1416      *      2C - Handle users deleted in backup file and "alive" in DB:
1417      *           If match mnethost and user is deleted in backup file
1418      *           and by email = email_without_time(backup_email) and non-zero firstaccess=> ok, return target user
1419      *      2D - Conflict: If match by username and mnethost and not by (email or non-zero firstaccess) => conflict, return false
1420      *      2E - None of the above, return true => User needs to be created
1421      *
1422      * Note: for DB deleted users email is stored in username field, hence we
1423      *       are looking there for emails. See delete_user()
1424      * Note: for DB deleted users md5(username) is stored *sometimes* in the email field,
1425      *       hence we are looking there for usernames if not empty. See delete_user()
1426      */
1427      protected static function precheck_user($user, $samesite, $siteid = null) {
1428          global $CFG, $DB;
1429  
1430          // Handle checks from same site backups
1431          if ($samesite && empty($CFG->forcedifferentsitecheckingusersonrestore)) {
1432  
1433              // 1A - If match by id and username and mnethost => ok, return target user
1434              if ($rec = $DB->get_record('user', array('id'=>$user->id, 'username'=>$user->username, 'mnethostid'=>$user->mnethostid))) {
1435                  return $rec; // Matching user found, return it
1436              }
1437  
1438              // 1B - If restoring an 'anonymous' user (created via the 'Anonymize user information' option) try to find a
1439              // match by username only => ok, return target user MDL-31484
1440              // This avoids username / id mis-match problems when restoring subsequent anonymized backups.
1441              if (backup_anonymizer_helper::is_anonymous_user($user)) {
1442                  if ($rec = $DB->get_record('user', array('username' => $user->username))) {
1443                      return $rec; // Matching anonymous user found - return it
1444                  }
1445              }
1446  
1447              // 1C - Handle users deleted in DB and "alive" in backup file
1448              // Note: for DB deleted users email is stored in username field, hence we
1449              //       are looking there for emails. See delete_user()
1450              // Note: for DB deleted users md5(username) is stored *sometimes* in the email field,
1451              //       hence we are looking there for usernames if not empty. See delete_user()
1452              // If match by id and mnethost and user is deleted in DB and
1453              // match by username LIKE 'substring(backup_email).%' where the substr length matches the retained data in the
1454              // username field (100 - (timestamp + 1) characters), or by non empty email = md5(username) => ok, return target user.
1455              $usernamelookup = core_text::substr($user->email, 0, 89) . '.%';
1456              if ($rec = $DB->get_record_sql("SELECT *
1457                                                FROM {user} u
1458                                               WHERE id = ?
1459                                                 AND mnethostid = ?
1460                                                 AND deleted = 1
1461                                                 AND (
1462                                                         UPPER(username) LIKE UPPER(?)
1463                                                      OR (
1464                                                             ".$DB->sql_isnotempty('user', 'email', false, false)."
1465                                                         AND email = ?
1466                                                         )
1467                                                     )",
1468                                             array($user->id, $user->mnethostid, $usernamelookup, md5($user->username)))) {
1469                  return $rec; // Matching user, deleted in DB found, return it
1470              }
1471  
1472              // 1D - Handle users deleted in backup file and "alive" in DB
1473              // If match by id and mnethost and user is deleted in backup file
1474              // and match by substring(email) = email_without_time(backup_email) where the substr length matches the retained data
1475              // in the username field (100 - (timestamp + 1) characters) => ok, return target user.
1476              if ($user->deleted) {
1477                  // Note: for DB deleted users email is stored in username field, hence we
1478                  //       are looking there for emails. See delete_user()
1479                  // Trim time() from email
1480                  $trimemail = preg_replace('/(.*?)\.[0-9]+.?$/', '\\1', $user->username);
1481                  if ($rec = $DB->get_record_sql("SELECT *
1482                                                    FROM {user} u
1483                                                   WHERE id = ?
1484                                                     AND mnethostid = ?
1485                                                     AND " . $DB->sql_substr('UPPER(email)', 1, 89) . " = UPPER(?)",
1486                                                 array($user->id, $user->mnethostid, $trimemail))) {
1487                      return $rec; // Matching user, deleted in backup file found, return it
1488                  }
1489              }
1490  
1491              // 1E - If match by username and mnethost and doesn't match by id => conflict, return false
1492              if ($rec = $DB->get_record('user', array('username'=>$user->username, 'mnethostid'=>$user->mnethostid))) {
1493                  if ($user->id != $rec->id) {
1494                      return false; // Conflict, username already exists and belongs to another id
1495                  }
1496              }
1497  
1498          // Handle checks from different site backups
1499          } else {
1500  
1501              // 2A1 - If match by username and mnethost and
1502              //     (email or non-zero firstaccess) => ok, return target user
1503              if ($rec = $DB->get_record_sql("SELECT *
1504                                                FROM {user} u
1505                                               WHERE username = ?
1506                                                 AND mnethostid = ?
1507                                                 AND (
1508                                                         UPPER(email) = UPPER(?)
1509                                                      OR (
1510                                                             firstaccess != 0
1511                                                         AND firstaccess = ?
1512                                                         )
1513                                                     )",
1514                                             array($user->username, $user->mnethostid, $user->email, $user->firstaccess))) {
1515                  return $rec; // Matching user found, return it
1516              }
1517  
1518              // 2A2 - If we're allowing conflicting admins, attempt to map user to admin_[oldsiteid].
1519              if (get_config('backup', 'import_general_duplicate_admin_allowed') && $user->username === 'admin' && $siteid
1520                      && $user->mnethostid == $CFG->mnet_localhost_id) {
1521                  if ($rec = $DB->get_record('user', array('username' => 'admin_' . $siteid))) {
1522                      return $rec;
1523                  }
1524              }
1525  
1526              // 2B - Handle users deleted in DB and "alive" in backup file
1527              // Note: for DB deleted users email is stored in username field, hence we
1528              //       are looking there for emails. See delete_user()
1529              // Note: for DB deleted users md5(username) is stored *sometimes* in the email field,
1530              //       hence we are looking there for usernames if not empty. See delete_user()
1531              // 2B1 - If match by mnethost and user is deleted in DB and not empty email = md5(username) and
1532              //       (by username LIKE 'substring(backup_email).%' or non-zero firstaccess) => ok, return target user.
1533              $usernamelookup = core_text::substr($user->email, 0, 89) . '.%';
1534              if ($rec = $DB->get_record_sql("SELECT *
1535                                                FROM {user} u
1536                                               WHERE mnethostid = ?
1537                                                 AND deleted = 1
1538                                                 AND ".$DB->sql_isnotempty('user', 'email', false, false)."
1539                                                 AND email = ?
1540                                                 AND (
1541                                                         UPPER(username) LIKE UPPER(?)
1542                                                      OR (
1543                                                             firstaccess != 0
1544                                                         AND firstaccess = ?
1545                                                         )
1546                                                     )",
1547                                             array($user->mnethostid, md5($user->username), $usernamelookup, $user->firstaccess))) {
1548                  return $rec; // Matching user found, return it
1549              }
1550  
1551              // 2B2 - If match by mnethost and user is deleted in DB and
1552              //       username LIKE 'substring(backup_email).%' and non-zero firstaccess) => ok, return target user
1553              //       (this covers situations where md5(username) wasn't being stored so we require both
1554              //        the email & non-zero firstaccess to match)
1555              $usernamelookup = core_text::substr($user->email, 0, 89) . '.%';
1556              if ($rec = $DB->get_record_sql("SELECT *
1557                                                FROM {user} u
1558                                               WHERE mnethostid = ?
1559                                                 AND deleted = 1
1560                                                 AND UPPER(username) LIKE UPPER(?)
1561                                                 AND firstaccess != 0
1562                                                 AND firstaccess = ?",
1563                                             array($user->mnethostid, $usernamelookup, $user->firstaccess))) {
1564                  return $rec; // Matching user found, return it
1565              }
1566  
1567              // 2C - Handle users deleted in backup file and "alive" in DB
1568              // If match mnethost and user is deleted in backup file
1569              // and match by substring(email) = email_without_time(backup_email) and non-zero firstaccess=> ok, return target user.
1570              if ($user->deleted) {
1571                  // Note: for DB deleted users email is stored in username field, hence we
1572                  //       are looking there for emails. See delete_user()
1573                  // Trim time() from email
1574                  $trimemail = preg_replace('/(.*?)\.[0-9]+.?$/', '\\1', $user->username);
1575                  if ($rec = $DB->get_record_sql("SELECT *
1576                                                    FROM {user} u
1577                                                   WHERE mnethostid = ?
1578                                                     AND " . $DB->sql_substr('UPPER(email)', 1, 89) . " = UPPER(?)
1579                                                     AND firstaccess != 0
1580                                                     AND firstaccess = ?",
1581                                                 array($user->mnethostid, $trimemail, $user->firstaccess))) {
1582                      return $rec; // Matching user, deleted in backup file found, return it
1583                  }
1584              }
1585  
1586              // 2D - If match by username and mnethost and not by (email or non-zero firstaccess) => conflict, return false
1587              if ($rec = $DB->get_record_sql("SELECT *
1588                                                FROM {user} u
1589                                               WHERE username = ?
1590                                                 AND mnethostid = ?
1591                                             AND NOT (
1592                                                         UPPER(email) = UPPER(?)
1593                                                      OR (
1594                                                             firstaccess != 0
1595                                                         AND firstaccess = ?
1596                                                         )
1597                                                     )",
1598                                             array($user->username, $user->mnethostid, $user->email, $user->firstaccess))) {
1599                  return false; // Conflict, username/mnethostid already exist and belong to another user (by email/firstaccess)
1600              }
1601          }
1602  
1603          // Arrived here, return true as the user will need to be created and no
1604          // conflicts have been found in the logic above. This covers:
1605          // 1E - else => user needs to be created, return true
1606          // 2E - else => user needs to be created, return true
1607          return true;
1608      }
1609  
1610      /**
1611       * Check all the included users, deciding the action to perform
1612       * for each one (mapping / creation) and returning one array
1613       * of problems in case something is wrong (lack of permissions,
1614       * conficts)
1615       *
1616       * @param string $restoreid Restore id
1617       * @param int $courseid Course id
1618       * @param int $userid User id
1619       * @param bool $samesite True if restore is to same site
1620       * @param \core\progress\base $progress Progress reporter
1621       */
1622      public static function precheck_included_users($restoreid, $courseid, $userid, $samesite,
1623              \core\progress\base $progress) {
1624          global $CFG, $DB;
1625  
1626          // To return any problem found
1627          $problems = array();
1628  
1629          // We are going to map mnethostid, so load all the available ones
1630          $mnethosts = $DB->get_records('mnet_host', array(), 'wwwroot', 'wwwroot, id');
1631  
1632          // Calculate the context we are going to use for capability checking
1633          $context = context_course::instance($courseid);
1634  
1635          // TODO: Some day we must kill this dependency and change the process
1636          // to pass info around without loading a controller copy.
1637          // When conflicting users are detected we may need original site info.
1638          $rc = restore_controller_dbops::load_controller($restoreid);
1639          $restoreinfo = $rc->get_info();
1640          $rc->destroy(); // Always need to destroy.
1641  
1642          // Calculate if we have perms to create users, by checking:
1643          // to 'moodle/restore:createuser' and 'moodle/restore:userinfo'
1644          // and also observe $CFG->disableusercreationonrestore
1645          $cancreateuser = false;
1646          if (has_capability('moodle/restore:createuser', $context, $userid) and
1647              has_capability('moodle/restore:userinfo', $context, $userid) and
1648              empty($CFG->disableusercreationonrestore)) { // Can create users
1649  
1650              $cancreateuser = true;
1651          }
1652  
1653          // Prepare for reporting progress.
1654          $conditions = array('backupid' => $restoreid, 'itemname' => 'user');
1655          $max = $DB->count_records('backup_ids_temp', $conditions);
1656          $done = 0;
1657          $progress->start_progress('Checking users', $max);
1658  
1659          // Iterate over all the included users
1660          $rs = $DB->get_recordset('backup_ids_temp', $conditions, '', 'itemid, info');
1661          foreach ($rs as $recuser) {
1662              $user = (object)backup_controller_dbops::decode_backup_temp_info($recuser->info);
1663  
1664              // Find the correct mnethostid for user before performing any further check
1665              if (empty($user->mnethosturl) || $user->mnethosturl === $CFG->wwwroot) {
1666                  $user->mnethostid = $CFG->mnet_localhost_id;
1667              } else {
1668                  // fast url-to-id lookups
1669                  if (isset($mnethosts[$user->mnethosturl])) {
1670                      $user->mnethostid = $mnethosts[$user->mnethosturl]->id;
1671                  } else {
1672                      $user->mnethostid = $CFG->mnet_localhost_id;
1673                  }
1674              }
1675  
1676              // Now, precheck that user and, based on returned results, annotate action/problem
1677              $usercheck = self::precheck_user($user, $samesite, $restoreinfo->original_site_identifier_hash);
1678  
1679              if (is_object($usercheck)) { // No problem, we have found one user in DB to be mapped to
1680                  // Annotate it, for later process. Set newitemid to mapping user->id
1681                  self::set_backup_ids_record($restoreid, 'user', $recuser->itemid, $usercheck->id);
1682  
1683              } else if ($usercheck === false) { // Found conflict, report it as problem
1684                  if (!get_config('backup', 'import_general_duplicate_admin_allowed')) {
1685                      $problems[] = get_string('restoreuserconflict', '', $user->username);
1686                  } else if ($user->username == 'admin') {
1687                      if (!$cancreateuser) {
1688                          $problems[] = get_string('restorecannotcreateuser', '', $user->username);
1689                      }
1690                      if ($user->mnethostid != $CFG->mnet_localhost_id) {
1691                          $problems[] = get_string('restoremnethostidmismatch', '', $user->username);
1692                      }
1693                      if (!$problems) {
1694                          // Duplicate admin allowed, append original site idenfitier to username.
1695                          $user->username .= '_' . $restoreinfo->original_site_identifier_hash;
1696                          self::set_backup_ids_record($restoreid, 'user', $recuser->itemid, 0, null, (array)$user);
1697                      }
1698                  }
1699  
1700              } else if ($usercheck === true) { // User needs to be created, check if we are able
1701                  if ($cancreateuser) { // Can create user, set newitemid to 0 so will be created later
1702                      self::set_backup_ids_record($restoreid, 'user', $recuser->itemid, 0, null, (array)$user);
1703  
1704                  } else { // Cannot create user, report it as problem
1705                      $problems[] = get_string('restorecannotcreateuser', '', $user->username);
1706                  }
1707  
1708              } else { // Shouldn't arrive here ever, something is for sure wrong. Exception
1709                  throw new restore_dbops_exception('restore_error_processing_user', $user->username);
1710              }
1711              $done++;
1712              $progress->progress($done);
1713          }
1714          $rs->close();
1715          $progress->end_progress();
1716          return $problems;
1717      }
1718  
1719      /**
1720       * Process the needed users in order to decide
1721       * which action to perform with them (create/map)
1722       *
1723       * Just wrap over precheck_included_users(), returning
1724       * exception if any problem is found
1725       *
1726       * @param string $restoreid Restore id
1727       * @param int $courseid Course id
1728       * @param int $userid User id
1729       * @param bool $samesite True if restore is to same site
1730       * @param \core\progress\base $progress Optional progress tracker
1731       */
1732      public static function process_included_users($restoreid, $courseid, $userid, $samesite,
1733              \core\progress\base $progress = null) {
1734          global $DB;
1735  
1736          // Just let precheck_included_users() to do all the hard work
1737          $problems = self::precheck_included_users($restoreid, $courseid, $userid, $samesite, $progress);
1738  
1739          // With problems, throw exception, shouldn't happen if prechecks were originally
1740          // executed, so be radical here.
1741          if (!empty($problems)) {
1742              throw new restore_dbops_exception('restore_problems_processing_users', null, implode(', ', $problems));
1743          }
1744      }
1745  
1746      /**
1747       * Process the needed question categories and questions
1748       * to check all them, deciding about the action to perform
1749       * (create/map) and target.
1750       *
1751       * Just wrap over precheck_categories_and_questions(), returning
1752       * exception if any problem is found
1753       */
1754      public static function process_categories_and_questions($restoreid, $courseid, $userid, $samesite) {
1755          global $DB;
1756  
1757          // Just let precheck_included_users() to do all the hard work
1758          $problems = self::precheck_categories_and_questions($restoreid, $courseid, $userid, $samesite);
1759  
1760          // With problems of type error, throw exception, shouldn't happen if prechecks were originally
1761          // executed, so be radical here.
1762          if (array_key_exists('errors', $problems)) {
1763              throw new restore_dbops_exception('restore_problems_processing_questions', null, implode(', ', $problems['errors']));
1764          }
1765      }
1766  
1767      public static function set_backup_files_record($restoreid, $filerec) {
1768          global $DB;
1769  
1770          // Store external files info in `info` field
1771          $filerec->info     = backup_controller_dbops::encode_backup_temp_info($filerec); // Encode the whole record into info.
1772          $filerec->backupid = $restoreid;
1773          $DB->insert_record('backup_files_temp', $filerec);
1774      }
1775  
1776      public static function set_backup_ids_record($restoreid, $itemname, $itemid, $newitemid = 0, $parentitemid = null, $info = null) {
1777          // Build conditionally the extra record info
1778          $extrarecord = array();
1779          if ($newitemid != 0) {
1780              $extrarecord['newitemid'] = $newitemid;
1781          }
1782          if ($parentitemid != null) {
1783              $extrarecord['parentitemid'] = $parentitemid;
1784          }
1785          if ($info != null) {
1786              $extrarecord['info'] = backup_controller_dbops::encode_backup_temp_info($info);
1787          }
1788  
1789          self::set_backup_ids_cached($restoreid, $itemname, $itemid, $extrarecord);
1790      }
1791  
1792      public static function get_backup_ids_record($restoreid, $itemname, $itemid) {
1793          $dbrec = self::get_backup_ids_cached($restoreid, $itemname, $itemid);
1794  
1795          // We must test if info is a string, as the cache stores info in object form.
1796          if ($dbrec && isset($dbrec->info) && is_string($dbrec->info)) {
1797              $dbrec->info = backup_controller_dbops::decode_backup_temp_info($dbrec->info);
1798          }
1799  
1800          return $dbrec;
1801      }
1802  
1803      /**
1804       * Given on courseid, fullname and shortname, calculate the correct fullname/shortname to avoid dupes
1805       */
1806      public static function calculate_course_names($courseid, $fullname, $shortname) {
1807          global $CFG, $DB;
1808  
1809          $counter = 0;
1810  
1811          // Iterate while fullname or shortname exist.
1812          do {
1813              if ($counter) {
1814                  $suffixfull  = ' ' . get_string('copyasnoun') . ' ' . $counter;
1815                  $suffixshort = '_' . $counter;
1816              } else {
1817                  $suffixfull  = '';
1818                  $suffixshort = '';
1819              }
1820  
1821              // Ensure we don't overflow maximum length of name fields, in multi-byte safe manner.
1822              $currentfullname = core_text::substr($fullname, 0, 254 - strlen($suffixfull)) . $suffixfull;
1823              $currentshortname = core_text::substr($shortname, 0, 100 - strlen($suffixshort)) . $suffixshort;
1824  
1825              $coursefull  = $DB->get_record_select('course', 'fullname = ? AND id != ?',
1826                      array($currentfullname, $courseid), '*', IGNORE_MULTIPLE);
1827              $courseshort = $DB->get_record_select('course', 'shortname = ? AND id != ?', array($currentshortname, $courseid));
1828              $counter++;
1829          } while ($coursefull || $courseshort);
1830  
1831          // Return results
1832          return array($currentfullname, $currentshortname);
1833      }
1834  
1835      /**
1836       * For the target course context, put as many custom role names as possible
1837       */
1838      public static function set_course_role_names($restoreid, $courseid) {
1839          global $DB;
1840  
1841          // Get the course context
1842          $coursectx = context_course::instance($courseid);
1843          // Get all the mapped roles we have
1844          $rs = $DB->get_recordset('backup_ids_temp', array('backupid' => $restoreid, 'itemname' => 'role'), '', 'itemid, info, newitemid');
1845          foreach ($rs as $recrole) {
1846              $info = backup_controller_dbops::decode_backup_temp_info($recrole->info);
1847              // If it's one mapped role and we have one name for it
1848              if (!empty($recrole->newitemid) && !empty($info['nameincourse'])) {
1849                  // If role name doesn't exist, add it
1850                  $rolename = new stdclass();
1851                  $rolename->roleid = $recrole->newitemid;
1852                  $rolename->contextid = $coursectx->id;
1853                  if (!$DB->record_exists('role_names', (array)$rolename)) {
1854                      $rolename->name = $info['nameincourse'];
1855                      $DB->insert_record('role_names', $rolename);
1856                  }
1857              }
1858          }
1859          $rs->close();
1860      }
1861  
1862      /**
1863       * Creates a skeleton record within the database using the passed parameters
1864       * and returns the new course id.
1865       *
1866       * @global moodle_database $DB
1867       * @param string $fullname
1868       * @param string $shortname
1869       * @param int $categoryid
1870       * @return int The new course id
1871       */
1872      public static function create_new_course($fullname, $shortname, $categoryid) {
1873          global $DB;
1874          $category = $DB->get_record('course_categories', array('id'=>$categoryid), '*', MUST_EXIST);
1875  
1876          $course = new stdClass;
1877          $course->fullname = $fullname;
1878          $course->shortname = $shortname;
1879          $course->category = $category->id;
1880          $course->sortorder = 0;
1881          $course->timecreated  = time();
1882          $course->timemodified = $course->timecreated;
1883          // forcing skeleton courses to be hidden instead of going by $category->visible , until MDL-27790 is resolved.
1884          $course->visible = 0;
1885  
1886          $courseid = $DB->insert_record('course', $course);
1887  
1888          $category->coursecount++;
1889          $DB->update_record('course_categories', $category);
1890  
1891          return $courseid;
1892      }
1893  
1894      /**
1895       * Deletes all of the content associated with the given course (courseid)
1896       * @param int $courseid
1897       * @param array $options
1898       * @return bool True for success
1899       */
1900      public static function delete_course_content($courseid, array $options = null) {
1901          return remove_course_contents($courseid, false, $options);
1902      }
1903  }
1904  
1905  /*
1906   * Exception class used by all the @dbops stuff
1907   */
1908  class restore_dbops_exception extends backup_exception {
1909  
1910      public function __construct($errorcode, $a=NULL, $debuginfo=null) {
1911          parent::__construct($errorcode, 'error', '', $a, null, $debuginfo);
1912      }
1913  }