question/restorelib.php

   1 <?php //$Id$
   2 /**
   3  * Question bank restore code.
   4  *
   5  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
   6  * @package questionbank
   7  *//** */
   8
   9 // Todo:
  10     // the restoration of the parent and sortorder fields in the category table needs
  11     // a lot more thought. We should probably use a library function to add the category
  12     // rather than just writing it to the database
  13
  14     // whereever it says "/// We have to recode the .... field" we should put in a check
  15     // to see if the recoding was successful and throw an appropriate error otherwise
  16
  17 //This is the "graphical" structure of the question database:
  18     //To see, put your terminal to 160cc
  19
  20     // The following holds student-independent information about the questions
  21     //
  22     //          question_categories
  23     //             (CL,pk->id)
  24     //                  |
  25     //                  |
  26     //                  |.......................................
  27     //                  |                                      .
  28     //                  |                                      .
  29     //                  |    -------question_datasets------    .
  30     //                  |    |  (CL,pk->id,fk->question,  |    .
  31     //                  |    |   fk->dataset_definition)  |    .
  32     //                  |    |                            |    .
  33     //                  |    |                            |    .
  34     //                  |    |                            |    .
  35     //                  |    |                    question_dataset_definitions
  36     //                  |    |                      (CL,pk->id,fk->category)
  37     //              question                                   |
  38     //        (CL,pk->id,fk->category,files)                   |
  39     //                  |                             question_dataset_items
  40     //                  |                          (CL,pk->id,fk->definition)
  41     //                  |
  42     //                  |
  43     //                  |
  44     //             --------------------------------------------------------------------------------------------------------------
  45     //             |             |              |              |                       |                  |                     |
  46     //             |             |              |              |                       |                  |                     |
  47     //             |             |              |              |             question_calculated          |                     |
  48     //      question_truefalse   |     question_multichoice    |          (CL,pl->id,fk->question)        |                     |
  49     // (CL,pk->id,fk->question)  |   (CL,pk->id,fk->question)  |                       .                  |                     |  question_randomsamatch
  50     //             .             |              .              |                       .                  |                     |--(CL,pk->id,fk->question)
  51     //             .    question_shortanswer    .      question_numerical              .         question_multianswer.          |
  52     //             .  (CL,pk->id,fk->question)  .  (CL,pk->id,fk->question)            .        (CL,pk->id,fk->question)        |
  53     //             .             .              .              .                       .                  .                     |       question_match
  54     //             .             .              .              .                       .                  .                     |--(CL,pk->id,fk->question)
  55     //             .             .              .              .                       .                  .                     |             .
  56     //             .             .              .              .                       .                  .                     |             .
  57     //             .             .              .              .                       .                  .                     |             .
  58     //             .             .              .              .                       .                  .                     |    question_match_sub
  59     //             ........................................................................................                     |--(CL,pk->id,fk->question)
  60     //                                                   .                                                                      |
  61     //                                                   .                                                                      |
  62     //                                                   .                                                                      |  question_numerical_units
  63     //                                             question_answers                                                             |--(CL,pk->id,fk->question)
  64     //                                         (CL,pk->id,fk->question)----------------------------------------------------------
  65     //
  66     //
  67     // The following holds the information about student interaction with the questions
  68     //
  69     //             question_sessions
  70     //      (UL,pk->id,fk->attempt,question)
  71     //                    .
  72     //                    .
  73     //             question_states
  74     //       (UL,pk->id,fk->attempt,question)
  75     //
  76     // Meaning: pk->primary key field of the table
  77     //          fk->foreign key to link with parent
  78     //          nt->nested field (recursive data)
  79     //          SL->site level info
  80     //          CL->course level info
  81     //          UL->user level info
  82     //          files->table may have files
  83     //
  84     //-----------------------------------------------------------
  85
  86     include_once($CFG->libdir.'/questionlib.php');
  87
  88     /**
  89     * Returns the best question category (id) found to restore one
  90     * question category from a backup file. Works by stamp.
  91     *
  92     * @param object $restore preferences for restoration
  93     * @param array $contextinfo fragment of decoded xml
  94     * @return object best context instance for this category to be in
  95     */
  96     function restore_question_get_best_category_context($restore, $contextinfo) {
  97         switch ($contextinfo['LEVEL'][0]['#']) {
  98             case 'module':
  99                 $instanceinfo = backup_getid($restore->backup_unique_code, 'course_modules', $contextinfo['INSTANCE'][0]['#']);
 100                 $tocontext = get_context_instance(CONTEXT_MODULE, $instanceinfo->new_id);
 101                 break;
 102             case 'course':
 103                 $tocontext = get_context_instance(CONTEXT_COURSE, $restore->course_id);
 104                 break;
 105             case 'coursecategory':
 106                 //search COURSECATEGORYLEVEL steps up the course cat tree or
 107                 //to the top of the tree if steps are exhausted.
 108                 $catno = $contextinfo['COURSECATEGORYLEVEL'][0]['#'];
 109                 $catid = get_field('course', 'parent', 'id', $restore->course_id);
 110                 while ($catno > 1){
 111                     $nextcatid = get_field('course_categories', 'parent', 'id', $catid);
 112                     if ($nextcatid == 0){
 113                         break;
 114                     }
 115                     $catid == $nextcatid;
 116                     $catno--;
 117                 }
 118                 $tocontext = get_context_instance(CONTEXT_COURSECAT, $catid);
 119                 break;
 120             case 'system':
 121                 $tocontext = get_context_instance(CONTEXT_SYSTEM);
 122                 break;
 123         }
 124         return $tocontext;
 125     }
 126
 127     function restore_question_categories($info, $restore) {
 128         $status = true;
 129         //Iterate over each category
 130         foreach ($info as $category) {
 131             $status = $status && restore_question_category($category, $restore);
 132         }
 133         $status = $status && restore_recode_category_parents($restore);
 134         return $status;
 135     }
 136
 137     function restore_question_category($category, $restore){
 138         $status = true;
 139         //Skip empty categories (some backups can contain them)
 140         if (!empty($category->id)) {
 141             //Get record from backup_ids
 142             $data = backup_getid($restore->backup_unique_code, "question_categories", $category->id);
 143
 144             if ($data) {
 145                 //Now get completed xmlized object
 146                 $info = $data->info;
 147                 //traverse_xmlize($info);                                                                     //Debug
 148                 //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 149                 //$GLOBALS['traverse_array']="";                                                              //Debug
 150
 151                 //Now, build the question_categories record structure
 152                 $question_cat = new stdClass;
 153                 $question_cat->name = backup_todb($info['QUESTION_CATEGORY']['#']['NAME']['0']['#']);
 154                 $question_cat->info = backup_todb($info['QUESTION_CATEGORY']['#']['INFO']['0']['#']);
 155                 $question_cat->stamp = backup_todb($info['QUESTION_CATEGORY']['#']['STAMP']['0']['#']);
 156                 //parent is fixed after all categories are restored and we know all the new ids.
 157                 $question_cat->parent = backup_todb($info['QUESTION_CATEGORY']['#']['PARENT']['0']['#']);
 158                 $question_cat->sortorder = backup_todb($info['QUESTION_CATEGORY']['#']['SORTORDER']['0']['#']);
 159                 if (!$question_cat->stamp) {
 160                     $question_cat->stamp = make_unique_id_code();
 161                 }
 162                 if (isset($info['QUESTION_CATEGORY']['#']['PUBLISH'])) {
 163                     $course = $restore->course_id;
 164                     $publish = backup_todb($info['QUESTION_CATEGORY']['#']['PUBLISH']['0']['#']);
 165                     if ($publish){
 166                         $tocontext = get_context_instance(CONTEXT_SYSTEM);
 167                     } else {
 168                         $tocontext = get_context_instance(CONTEXT_COURSE, $course);
 169                     }
 170                 } else {
 171                     $tocontext = restore_question_get_best_category_context($restore, $info['QUESTION_CATEGORY']['#']['CONTEXT']['0']['#']);
 172                 }
 173                 $question_cat->contextid = $tocontext->id;
 174
 175                 //does cat exist ?? if it does we check if the cat and questions already exist whether we have
 176                 //add permission or not if we have no permission to add questions to SYSTEM or COURSECAT context
 177                 //AND the question does not already exist then we create questions in COURSE context.
 178                 if (!$fcat = get_record('question_categories','contextid', $question_cat->contextid, 'stamp', $question_cat->stamp)){
 179                     //no preexisting cat
 180                     if ((($tocontext->contextlevel == CONTEXT_SYSTEM) ||  ($tocontext->contextlevel == CONTEXT_COURSECAT))
 181                             && !has_capability('moodle/question:add', $tocontext)){
 182                         //no preexisting cat and no permission to create questions here
 183                         //must restore to course.
 184                         $tocontext = get_context_instance(CONTEXT_COURSE, $restore->course_id);
 185                     }
 186                     $question_cat->contextid = $tocontext->id;
 187                     if (!$fcat = get_record('question_categories','contextid', $question_cat->contextid, 'stamp', $question_cat->stamp)){
 188                         $question_cat->id = insert_record ("question_categories", $question_cat);
 189                     } else {
 190                         $question_cat = $fcat;
 191                     }
 192                     //we'll be restoring all questions here.
 193                     backup_putid($restore->backup_unique_code, "question_categories", $category->id, $question_cat->id);
 194                 } else {
 195                     $question_cat = $fcat;
 196                     //we found an existing best category
 197                     //but later if context is above course need to check if there are questions need creating in category
 198                     //if we do need to create questions and permissions don't allow it create new category in course
 199                 }
 200
 201                 //Do some output
 202                 if (!defined('RESTORE_SILENTLY')) {
 203                     echo "<li>".get_string('category', 'quiz')." \"".$question_cat->name."\"<br />";
 204                 }
 205
 206                 backup_flush(300);
 207
 208                 //start with questions
 209                 if ($question_cat->id) {
 210                     //We have the newid, update backup_ids
 211                     //Now restore question
 212                     $status = restore_questions($category->id, $question_cat, $info, $restore);
 213                 } else {
 214                     $status = false;
 215                 }
 216                 if (!defined('RESTORE_SILENTLY')) {
 217                     echo '</li>';
 218                 }
 219             } else {
 220                 echo 'Could not get backup info for question category'. $category->id;
 221             }
 222         }
 223         return $status;
 224     }
 225
 226     function restore_recode_category_parents($restore){
 227         global $CFG;
 228         $status = true;
 229         //Now we have to recode the parent field of each restored category
 230         $categories = get_records_sql("SELECT old_id, new_id
 231                                        FROM {$CFG->prefix}backup_ids
 232                                        WHERE backup_code = $restore->backup_unique_code AND
 233                                              table_name = 'question_categories'");
 234         if ($categories) {
 235             //recode all parents to point at their old parent cats no matter what context the parent is now in
 236             foreach ($categories as $category) {
 237                 $restoredcategory = get_record('question_categories','id',$category->new_id);
 238                 if ($restoredcategory->parent != 0) {
 239                     $updateobj = new object();
 240                     $updateobj->id = $restoredcategory->id;
 241                     $idcat = backup_getid($restore->backup_unique_code,'question_categories',$restoredcategory->parent);
 242                     if ($idcat->new_id) {
 243                         $updateobj->parent = $idcat->new_id;
 244                     } else {
 245                         $updateobj->parent = 0;
 246                     }
 247                     $status = $status && update_record('question_categories', $updateobj);
 248                 }
 249             }
 250             //now we have recoded all parents, check through all parents and set parent to be
 251             //grand parent / great grandparent etc where there is one in same context
 252             //or else set parent to 0 (top level category).
 253             $toupdate = array();
 254             foreach ($categories as $category) {
 255                 $restoredcategory = get_record('question_categories','id',$category->new_id);
 256                 if ($restoredcategory->parent != 0) {
 257                     $nextparentid = $restoredcategory->parent;
 258                     do {
 259                         if (!$parent = get_record('question_categories', 'id', $nextparentid)){
 260                             if (!defined('RESTORE_SILENTLY')) {
 261                                 echo 'Could not find parent for question category '. $category->id.' recoding as top category item.<br />';
 262                             }
 263                             break;//record fetch failed finish loop
 264                         } else {
 265                             $nextparentid = $nextparent->parent;
 266                         }
 267                     } while (($nextparentid != 0) && ($parent->contextid != $restoredcategory->contextid));
 268                     if (!$parent || ($parent->id != $restoredcategory->parent)){
 269                         //change needs to be made to the parent field.
 270                         if ($parent && ($parent->contextid == $restoredcategory->contextid)){
 271                             $toupdate[$restoredcategory->id] = $parent->id;
 272                         } else {
 273                             //searched up the tree till we came to the top and did not find cat in same
 274                             //context or there was an error getting next parent record
 275                             $toupdate[$restoredcategory->id] = 0;
 276                         }
 277                     }
 278                 }
 279             }
 280             //now finally do the changes to parent field.
 281             foreach ($toupdate as  $id => $parent){
 282                 $updateobj = new object();
 283                 $updateobj->id = $id;
 284                 $updateobj->parent = $parent;
 285                 $status = $status && update_record('question_categories', $updateobj);
 286             }
 287         }
 288         return $status;
 289     }
 290
 291     function restore_questions ($old_category_id, $best_question_cat, $info, $restore) {
 292
 293         global $CFG, $QTYPES;
 294
 295         $status = true;
 296         $restored_questions = array();
 297
 298         //Get the questions array
 299         if (!empty($info['QUESTION_CATEGORY']['#']['QUESTIONS'])) {
 300             $questions = $info['QUESTION_CATEGORY']['#']['QUESTIONS']['0']['#']['QUESTION'];
 301         } else {
 302             $questions = array();
 303         }
 304
 305         //Iterate over questions
 306         for($i = 0; $i < sizeof($questions); $i++) {
 307             $que_info = $questions[$i];
 308             //traverse_xmlize($que_info);                                                                 //Debug
 309             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 310             //$GLOBALS['traverse_array']="";                                                              //Debug
 311
 312             //We'll need this later!!
 313             $oldid = backup_todb($que_info['#']['ID']['0']['#']);
 314
 315             //Now, build the question record structure
 316             $question = new object;
 317             $question->parent = backup_todb($que_info['#']['PARENT']['0']['#']);
 318             $question->name = backup_todb($que_info['#']['NAME']['0']['#']);
 319             $question->questiontext = backup_todb($que_info['#']['QUESTIONTEXT']['0']['#']);
 320             $question->questiontextformat = backup_todb($que_info['#']['QUESTIONTEXTFORMAT']['0']['#']);
 321             $question->image = backup_todb($que_info['#']['IMAGE']['0']['#']);
 322             if (array_key_exists('GENERALFEEDBACK', $que_info['#'])) {
 323                 $question->generalfeedback = backup_todb($que_info['#']['GENERALFEEDBACK']['0']['#']);
 324             } else {
 325                 $question->generalfeedback = '';
 326             }
 327             $question->defaultgrade = backup_todb($que_info['#']['DEFAULTGRADE']['0']['#']);
 328             $question->penalty = backup_todb($que_info['#']['PENALTY']['0']['#']);
 329             $question->qtype = backup_todb($que_info['#']['QTYPE']['0']['#']);
 330             $question->length = backup_todb($que_info['#']['LENGTH']['0']['#']);
 331             $question->stamp = backup_todb($que_info['#']['STAMP']['0']['#']);
 332             $question->version = backup_todb($que_info['#']['VERSION']['0']['#']);
 333             $question->hidden = backup_todb($que_info['#']['HIDDEN']['0']['#']);
 334             $question->timecreated = backup_todb($que_info['#']['TIMECREATED']['0']['#']);
 335             $question->timemodified = backup_todb($que_info['#']['TIMEMODIFIED']['0']['#']);
 336             $question->createdby = backup_todb($que_info['#']['CREATEDBY']['0']['#']);
 337             $question->modifiedby = backup_todb($que_info['#']['MODIFIEDBY']['0']['#']);
 338
 339             if ($restore->backup_version < 2006032200) {
 340                 // The qtype was an integer that now needs to be converted to the name
 341                 $qtypenames = array(1=>'shortanswer',2=>'truefalse',3=>'multichoice',4=>'random',5=>'match',
 342                  6=>'randomsamatch',7=>'description',8=>'numerical',9=>'multianswer',10=>'calculated',
 343                  11=>'rqp',12=>'essay');
 344                 $question->qtype = $qtypenames[$question->qtype];
 345             }
 346
 347             //Check if the question exists by category, stamp, and version
 348             //first check for the question in the context specified in backup
 349             $existingquestion = get_record ("question", "category", $best_question_cat->id, "stamp", $question->stamp,"version",$question->version);
 350             //If the question exists, only record its id
 351             //always use existing question, no permissions check here
 352             if ($existingquestion) {
 353                 $question = $existingquestion;
 354                 $creatingnewquestion = false;
 355             } else {
 356                 //then if context above course level check permissions and if no permission
 357                 //to restore above course level then restore to cat in course context.
 358                 $bestcontext = get_context_instance_by_id($best_question_cat->contextid);
 359                 if (($bestcontext->contextlevel == CONTEXT_SYSTEM ||  $bestcontext->contextlevel == CONTEXT_COURSECAT)
 360                         && !has_capability('moodle/question:add', $bestcontext)){
 361                     if (!isset($course_question_cat)) {
 362                         $coursecontext = get_context_instance(CONTEXT_COURSE, $restore->course_id);
 363                         $course_question_cat = clone($best_question_cat);
 364                         $course_question_cat->contextid = $coursecontext->id;
 365                         //create cat if it doesn't exist
 366                         if (!$fcat = get_record('question_categories','contextid', $course_question_cat->contextid, 'stamp', $course_question_cat->stamp)){
 367                             $course_question_cat->id = insert_record ("question_categories", $course_question_cat);
 368                             backup_putid($restore->backup_unique_code, "question_categories", $old_category_id, $course_question_cat->id);
 369                         } else {
 370                             $course_question_cat = $fcat;
 371                         }
 372                         //will fix category parents after all questions and categories restored. Will set parent to 0 if
 373                         //no parent in same context.
 374                     }
 375                     $question->category = $course_question_cat->id;
 376                     //does question already exist in course cat
 377                     $existingquestion = get_record ("question", "category", $question->category, "stamp", $question->stamp, "version", $question->version);
 378                 } else {
 379                     //permissions ok, restore to best cat
 380                     $question->category = $best_question_cat->id;
 381                 }
 382                 if (!$existingquestion){
 383                     //The structure is equal to the db, so insert the question
 384                     $question->id = insert_record ("question", $question);
 385                     $creatingnewquestion = true;
 386                 } else {
 387                     $question = $existingquestion;
 388                     $creatingnewquestion = false;
 389                 }
 390             }
 391
 392             //Save newid to backup tables
 393             if ($question->id) {
 394                 //We have the newid, update backup_ids
 395                 backup_putid($restore->backup_unique_code, "question", $oldid, $question->id);
 396             }
 397
 398             $restored_questions[$i] = new stdClass;
 399             $restored_questions[$i]->newid  = $question->id;
 400             $restored_questions[$i]->oldid  = $oldid;
 401             $restored_questions[$i]->qtype  = $question->qtype;
 402             $restored_questions[$i]->parent = $question->parent;
 403             $restored_questions[$i]->is_new = $creatingnewquestion;
 404         }
 405         backup_flush(300);
 406
 407         // Loop again, now all the question id mappings exist, so everything can
 408         // be restored.
 409         for($i = 0; $i < sizeof($questions); $i++) {
 410             $que_info = $questions[$i];
 411
 412             $newid = $restored_questions[$i]->newid;
 413             $oldid = $restored_questions[$i]->oldid;
 414
 415             $question = new object;
 416             $question->qtype = $restored_questions[$i]->qtype;
 417             $question->parent = $restored_questions[$i]->parent;
 418
 419
 420             //If it's a new question in the DB, restore it
 421             if ($restored_questions[$i]->is_new) {
 422
 423                 ////We have to recode the parent field
 424                 if ($question->parent) {
 425                     if ($parent = backup_getid($restore->backup_unique_code,"question",$question->parent)) {
 426                         $question->parent = $parent->new_id;
 427                     } elseif ($question->parent = $oldid) {
 428                         $question->parent = $newid;
 429                     } else {
 430                         echo 'Could not recode parent '.$question->parent.' for question '.$oldid.'<br />';
 431                     }
 432                 }
 433
 434                 //Now, restore every question_answers in this question
 435                 $status = question_restore_answers($oldid,$newid,$que_info,$restore);
 436                 // Restore questiontype specific data
 437                 if (array_key_exists($question->qtype, $QTYPES)) {
 438                     $status = $QTYPES[$question->qtype]->restore($oldid,$newid,$que_info,$restore);
 439                 } else {
 440                     echo 'Unknown question type '.$question->qtype.' for question '.$oldid.'<br />';
 441                     $status = false;
 442                 }
 443             } else {
 444                 //We are NOT creating the question, but we need to know every question_answers
 445                 //map between the XML file and the database to be able to restore the states
 446                 //in each attempt.
 447                 $status = question_restore_map_answers($oldid,$newid,$que_info,$restore);
 448                 // Do the questiontype specific mapping
 449                 if (array_key_exists($question->qtype, $QTYPES)) {
 450                     $status = $QTYPES[$question->qtype]->restore_map($oldid,$newid,$que_info,$restore);
 451                 } else {
 452                     echo 'Unknown question type '.$question->qtype.' for question '.$oldid.'<br />';
 453                     $status = false;
 454                 }
 455             }
 456
 457             //Do some output
 458             if (($i+1) % 2 == 0) {
 459                 if (!defined('RESTORE_SILENTLY')) {
 460                     echo ".";
 461                     if (($i+1) % 40 == 0) {
 462                         echo "<br />";
 463                     }
 464                 }
 465                 backup_flush(300);
 466             }
 467         }
 468         return $status;
 469     }
 470
 471     function question_restore_answers ($old_question_id,$new_question_id,$info,$restore) {
 472
 473         global $CFG;
 474
 475         $status = true;
 476         $qtype = backup_todb($info['#']['QTYPE']['0']['#']);
 477
 478         //Get the answers array
 479         if (isset($info['#']['ANSWERS']['0']['#']['ANSWER'])) {
 480             $answers = $info['#']['ANSWERS']['0']['#']['ANSWER'];
 481
 482             //Iterate over answers
 483             for($i = 0; $i < sizeof($answers); $i++) {
 484                 $ans_info = $answers[$i];
 485                 //traverse_xmlize($ans_info);                                                                 //Debug
 486                 //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 487                 //$GLOBALS['traverse_array']="";                                                              //Debug
 488
 489                 //We'll need this later!!
 490                 $oldid = backup_todb($ans_info['#']['ID']['0']['#']);
 491
 492                 //Now, build the question_answers record structure
 493                 $answer = new stdClass;
 494                 $answer->question = $new_question_id;
 495                 $answer->answer = backup_todb($ans_info['#']['ANSWER_TEXT']['0']['#']);
 496                 $answer->fraction = backup_todb($ans_info['#']['FRACTION']['0']['#']);
 497                 $answer->feedback = backup_todb($ans_info['#']['FEEDBACK']['0']['#']);
 498
 499                 // Update 'match everything' answers for numerical questions coming from old backup files.
 500                 if ($qtype == 'numerical' && $answer->answer == '') {
 501                     $answer->answer = '*';
 502                 }
 503
 504                 //The structure is equal to the db, so insert the question_answers
 505                 $newid = insert_record ("question_answers",$answer);
 506
 507                 //Do some output
 508                 if (($i+1) % 50 == 0) {
 509                     if (!defined('RESTORE_SILENTLY')) {
 510                         echo ".";
 511                         if (($i+1) % 1000 == 0) {
 512                             echo "<br />";
 513                         }
 514                     }
 515                     backup_flush(300);
 516                 }
 517
 518                 if ($newid) {
 519                     //We have the newid, update backup_ids
 520                     backup_putid($restore->backup_unique_code,"question_answers",$oldid,
 521                                  $newid);
 522                 } else {
 523                     $status = false;
 524                 }
 525             }
 526         }
 527
 528         return $status;
 529     }
 530
 531     function question_restore_map_answers ($old_question_id,$new_question_id,$info,$restore) {
 532
 533         global $CFG;
 534
 535         $status = true;
 536
 537         if (!isset($info['#']['ANSWERS'])) {    // No answers in this question (eg random)
 538             return $status;
 539         }
 540
 541         //Get the answers array
 542         $answers = $info['#']['ANSWERS']['0']['#']['ANSWER'];
 543
 544         //Iterate over answers
 545         for($i = 0; $i < sizeof($answers); $i++) {
 546             $ans_info = $answers[$i];
 547             //traverse_xmlize($ans_info);                                                                 //Debug
 548             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 549             //$GLOBALS['traverse_array']="";                                                              //Debug
 550
 551             //We'll need this later!!
 552             $oldid = backup_todb($ans_info['#']['ID']['0']['#']);
 553
 554             //Now, build the question_answers record structure
 555             $answer->question = $new_question_id;
 556             $answer->answer = backup_todb($ans_info['#']['ANSWER_TEXT']['0']['#']);
 557             $answer->fraction = backup_todb($ans_info['#']['FRACTION']['0']['#']);
 558             $answer->feedback = backup_todb($ans_info['#']['FEEDBACK']['0']['#']);
 559
 560             //If we are in this method is because the question exists in DB, so its
 561             //answers must exist too.
 562             //Now, we are going to look for that answer in DB and to create the
 563             //mappings in backup_ids to use them later where restoring states (user level).
 564
 565             //Get the answer from DB (by question and answer)
 566             $db_answer = get_record ("question_answers","question",$new_question_id,
 567                                                     "answer",$answer->answer);
 568
 569             //Do some output
 570             if (($i+1) % 50 == 0) {
 571                 if (!defined('RESTORE_SILENTLY')) {
 572                     echo ".";
 573                     if (($i+1) % 1000 == 0) {
 574                         echo "<br />";
 575                     }
 576                 }
 577                 backup_flush(300);
 578             }
 579
 580             if ($db_answer) {
 581                 //We have the database answer, update backup_ids
 582                 backup_putid($restore->backup_unique_code,"question_answers",$oldid,
 583                              $db_answer->id);
 584             } else {
 585                 $status = false;
 586             }
 587         }
 588
 589         return $status;
 590     }
 591
 592     function question_restore_numerical_units($old_question_id,$new_question_id,$info,$restore) {
 593
 594         global $CFG;
 595
 596         $status = true;
 597
 598         //Get the numerical array
 599         if (!empty($info['#']['NUMERICAL_UNITS'])) {
 600             $numerical_units = $info['#']['NUMERICAL_UNITS']['0']['#']['NUMERICAL_UNIT'];
 601         } else {
 602             $numerical_units = array();
 603         }
 604
 605         //Iterate over numerical_units
 606         for($i = 0; $i < sizeof($numerical_units); $i++) {
 607             $nu_info = $numerical_units[$i];
 608             //traverse_xmlize($nu_info);                                                                  //Debug
 609             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 610             //$GLOBALS['traverse_array']="";                                                              //Debug
 611
 612             // Check to see if this until already exists in the database, which it might, for
 613             // Historical reasons.
 614             $unit = backup_todb($nu_info['#']['UNIT']['0']['#']);
 615             if (!record_exists('question_numerical_units', 'question', $new_question_id, 'unit', $unit)) {
 616
 617                 //Now, build the question_numerical_UNITS record structure.
 618                 $numerical_unit = new stdClass;
 619                 $numerical_unit->question = $new_question_id;
 620                 $numerical_unit->multiplier = backup_todb($nu_info['#']['MULTIPLIER']['0']['#']);
 621                 $numerical_unit->unit = $unit;
 622
 623                 //The structure is equal to the db, so insert the question_numerical_units
 624                 $newid = insert_record("question_numerical_units", $numerical_unit);
 625
 626                 if (!$newid) {
 627                     $status = false;
 628                 }
 629             }
 630         }
 631
 632         return $status;
 633     }
 634
 635     function question_restore_dataset_definitions ($old_question_id,$new_question_id,$info,$restore) {
 636
 637         global $CFG;
 638
 639         $status = true;
 640
 641         //Get the dataset_definitions array
 642         $dataset_definitions = $info['#']['DATASET_DEFINITIONS']['0']['#']['DATASET_DEFINITION'];
 643
 644         //Iterate over dataset_definitions
 645         for($i = 0; $i < sizeof($dataset_definitions); $i++) {
 646             $dd_info = $dataset_definitions[$i];
 647             //traverse_xmlize($dd_info);                                                                  //Debug
 648             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 649             //$GLOBALS['traverse_array']="";                                                              //Debug
 650
 651             //Now, build the question_dataset_DEFINITION record structure
 652             $dataset_definition = new stdClass;
 653             $dataset_definition->category = backup_todb($dd_info['#']['CATEGORY']['0']['#']);
 654             $dataset_definition->name = backup_todb($dd_info['#']['NAME']['0']['#']);
 655             $dataset_definition->type = backup_todb($dd_info['#']['TYPE']['0']['#']);
 656             $dataset_definition->options = backup_todb($dd_info['#']['OPTIONS']['0']['#']);
 657             $dataset_definition->itemcount = backup_todb($dd_info['#']['ITEMCOUNT']['0']['#']);
 658
 659             //We have to recode the category field (only if the category != 0)
 660             if ($dataset_definition->category != 0) {
 661                 $category = backup_getid($restore->backup_unique_code,"question_categories",$dataset_definition->category);
 662                 if ($category) {
 663                     $dataset_definition->category = $category->new_id;
 664                 } else {
 665                     echo 'Could not recode category id '.$dataset_definition->category.' for dataset definition'.$dataset_definition->name.'<br />';
 666                 }
 667             }
 668
 669             //Now, we hace to decide when to create the new records or reuse an existing one
 670             $create_definition = false;
 671
 672             //If the dataset_definition->category = 0, it's a individual question dataset_definition, so we'll create it
 673             if ($dataset_definition->category == 0) {
 674                 $create_definition = true;
 675             } else {
 676                 //The category isn't 0, so it's a category question dataset_definition, we have to see if it exists
 677                 //Look for a definition with the same category, name and type
 678                 if ($definitionrec = get_record_sql("SELECT d.*
 679                                                      FROM {$CFG->prefix}question_dataset_definitions d
 680                                                      WHERE d.category = '$dataset_definition->category' AND
 681                                                            d.name = '$dataset_definition->name' AND
 682                                                            d.type = '$dataset_definition->type'")) {
 683                     //Such dataset_definition exist. Now we must check if it has enough itemcount
 684                     if ($definitionrec->itemcount < $dataset_definition->itemcount) {
 685                         //We haven't enough itemcount, so we have to create the definition as an individual question one.
 686                         $dataset_definition->category = 0;
 687                         $create_definition = true;
 688                     } else {
 689                         //We have enough itemcount, so we'll reuse the existing definition
 690                         $create_definition = false;
 691                         $newid = $definitionrec->id;
 692                     }
 693                 } else {
 694                     //Such dataset_definition doesn't exist. We'll create it.
 695                     $create_definition = true;
 696                 }
 697             }
 698
 699             //If we've to create the definition, do it
 700             if ($create_definition) {
 701                 //The structure is equal to the db, so insert the question_dataset_definitions
 702                 $newid = insert_record ("question_dataset_definitions",$dataset_definition);
 703                 if ($newid) {
 704                     //Restore question_dataset_items
 705                     $status = question_restore_dataset_items($newid,$dd_info,$restore);
 706                 }
 707             }
 708
 709             //Now, we must have a definition (created o reused). Its id is in newid. Create the question_datasets record
 710             //to join the question and the dataset_definition
 711             if ($newid) {
 712                 $question_dataset = new stdClass;
 713                 $question_dataset->question = $new_question_id;
 714                 $question_dataset->datasetdefinition = $newid;
 715                 $newid = insert_record ("question_datasets",$question_dataset);
 716             }
 717
 718             if (!$newid) {
 719                 $status = false;
 720             }
 721         }
 722
 723         return $status;
 724     }
 725
 726     function question_restore_dataset_items ($definitionid,$info,$restore) {
 727
 728         global $CFG;
 729
 730         $status = true;
 731
 732         //Get the items array
 733         $dataset_items = $info['#']['DATASET_ITEMS']['0']['#']['DATASET_ITEM'];
 734
 735         //Iterate over dataset_items
 736         for($i = 0; $i < sizeof($dataset_items); $i++) {
 737             $di_info = $dataset_items[$i];
 738             //traverse_xmlize($di_info);                                                                  //Debug
 739             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 740             //$GLOBALS['traverse_array']="";                                                              //Debug
 741
 742             //Now, build the question_dataset_ITEMS record structure
 743             $dataset_item = new stdClass;
 744             $dataset_item->definition = $definitionid;
 745             $dataset_item->itemnumber = backup_todb($di_info['#']['NUMBER']['0']['#']);
 746             $dataset_item->value = backup_todb($di_info['#']['VALUE']['0']['#']);
 747
 748             //The structure is equal to the db, so insert the question_dataset_items
 749             $newid = insert_record ("question_dataset_items",$dataset_item);
 750
 751             if (!$newid) {
 752                 $status = false;
 753             }
 754         }
 755
 756         return $status;
 757     }
 758
 759
 760     //This function restores the question_states
 761     function question_states_restore_mods($attempt_id,$info,$restore) {
 762
 763         global $CFG, $QTYPES;
 764
 765         $status = true;
 766
 767         //Get the question_states array
 768         $states = $info['#']['STATES']['0']['#']['STATE'];
 769         //Iterate over states
 770         for($i = 0; $i < sizeof($states); $i++) {
 771             $res_info = $states[$i];
 772             //traverse_xmlize($res_info);                                                                 //Debug
 773             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 774             //$GLOBALS['traverse_array']="";                                                              //Debug
 775
 776             //We'll need this later!!
 777             $oldid = backup_todb($res_info['#']['ID']['0']['#']);
 778
 779             //Now, build the STATES record structure
 780             $state = new stdClass;
 781             $state->attempt = $attempt_id;
 782             $state->question = backup_todb($res_info['#']['QUESTION']['0']['#']);
 783             $state->originalquestion = backup_todb($res_info['#']['ORIGINALQUESTION']['0']['#']);
 784             $state->seq_number = backup_todb($res_info['#']['SEQ_NUMBER']['0']['#']);
 785             $state->answer = backup_todb($res_info['#']['ANSWER']['0']['#']);
 786             $state->timestamp = backup_todb($res_info['#']['TIMESTAMP']['0']['#']);
 787             $state->event = backup_todb($res_info['#']['EVENT']['0']['#']);
 788             $state->grade = backup_todb($res_info['#']['GRADE']['0']['#']);
 789             $state->raw_grade = backup_todb($res_info['#']['RAW_GRADE']['0']['#']);
 790             $state->penalty = backup_todb($res_info['#']['PENALTY']['0']['#']);
 791             $state->oldid = $oldid; // So it is available to restore_recode_answer.
 792
 793             //We have to recode the question field
 794             $question = backup_getid($restore->backup_unique_code,"question",$state->question);
 795             if ($question) {
 796                 $state->question = $question->new_id;
 797             } else {
 798                 echo 'Could not recode question id '.$state->question.' for state '.$oldid.'<br />';
 799             }
 800
 801             //We have to recode the originalquestion field if it is nonzero
 802             if ($state->originalquestion) {
 803                 $question = backup_getid($restore->backup_unique_code,"question",$state->originalquestion);
 804                 if ($question) {
 805                     $state->originalquestion = $question->new_id;
 806                 } else {
 807                     echo 'Could not recode originalquestion id '.$state->question.' for state '.$oldid.'<br />';
 808                 }
 809             }
 810
 811             //We have to recode the answer field
 812             //It depends of the question type !!
 813             //We get the question first
 814             if (!$question = get_record("question","id",$state->question)) {
 815                 error("Can't find the record for question $state->question for which I am trying to restore a state");
 816             }
 817             //Depending on the qtype, we make different recodes
 818             if ($state->answer) {
 819                 $state->answer = $QTYPES[$question->qtype]->restore_recode_answer($state, $restore);
 820             }
 821
 822             //The structure is equal to the db, so insert the question_states
 823             $newid = insert_record ("question_states",$state);
 824
 825             //Do some output
 826             if (($i+1) % 10 == 0) {
 827                 if (!defined('RESTORE_SILENTLY')) {
 828                     echo ".";
 829                     if (($i+1) % 200 == 0) {
 830                         echo "<br />";
 831                     }
 832                 }
 833                 backup_flush(300);
 834             }
 835
 836             if ($newid) {
 837                 //We have the newid, update backup_ids
 838                 backup_putid($restore->backup_unique_code, 'question_states', $oldid, $newid);
 839             } else {
 840                 $status = false;
 841             }
 842         }
 843
 844         //Get the question_sessions array
 845         $sessions = $info['#']['NEWEST_STATES']['0']['#']['NEWEST_STATE'];
 846         //Iterate over question_sessions
 847         for($i = 0; $i < sizeof($sessions); $i++) {
 848             $res_info = $sessions[$i];
 849             //traverse_xmlize($res_info);                                                                 //Debug
 850             //print_object ($GLOBALS['traverse_array']);                                                  //Debug
 851             //$GLOBALS['traverse_array']="";                                                              //Debug
 852
 853             //Now, build the NEWEST_STATES record structure
 854             $session = new stdClass;
 855             $session->attemptid = $attempt_id;
 856             $session->questionid = backup_todb($res_info['#']['QUESTIONID']['0']['#']);
 857             $session->newest = backup_todb($res_info['#']['NEWEST']['0']['#']);
 858             $session->newgraded = backup_todb($res_info['#']['NEWGRADED']['0']['#']);
 859             $session->sumpenalty = backup_todb($res_info['#']['SUMPENALTY']['0']['#']);
 860
 861             if ($res_info['#']['MANUALCOMMENT']['0']['#']) {
 862                 $session->manualcomment = backup_todb($res_info['#']['MANUALCOMMENT']['0']['#']);
 863             } else { // pre 1.7 backups
 864                 $session->manualcomment = backup_todb($res_info['#']['COMMENT']['0']['#']);
 865             }
 866
 867             //We have to recode the question field
 868             $question = backup_getid($restore->backup_unique_code,"question",$session->questionid);
 869             if ($question) {
 870                 $session->questionid = $question->new_id;
 871             } else {
 872                 echo 'Could not recode question id '.$session->questionid.'<br />';
 873             }
 874
 875             //We have to recode the newest field
 876             $state = backup_getid($restore->backup_unique_code,"question_states",$session->newest);
 877             if ($state) {
 878                 $session->newest = $state->new_id;
 879             } else {
 880                 echo 'Could not recode newest state id '.$session->newest.'<br />';
 881             }
 882
 883             //If the session has been graded we have to recode the newgraded field
 884             if ($session->newgraded) {
 885                 $state = backup_getid($restore->backup_unique_code,"question_states",$session->newgraded);
 886                 if ($state) {
 887                     $session->newgraded = $state->new_id;
 888                 } else {
 889                     echo 'Could not recode newest graded state id '.$session->newgraded.'<br />';
 890                 }
 891             }
 892
 893             //The structure is equal to the db, so insert the question_sessions
 894             $newid = insert_record ("question_sessions",$session);
 895
 896         }
 897
 898         return $status;
 899     }
 900
 901     /**
 902      * Recode content links in question texts.
 903      * @param object $restore the restore metadata object.
 904      * @return boolean whether the operation succeeded.
 905      */
 906     function question_decode_content_links_caller($restore) {
 907         global $CFG, $QTYPES;
 908         $status = true;
 909         $i = 1;   //Counter to send some output to the browser to avoid timeouts
 910
 911         // Get a list of which question types have custom field that will need decoding.
 912         $qtypeswithextrafields = array();
 913         $qtypeswithhtmlanswers = array();
 914         foreach ($QTYPES as $qtype => $qtypeclass) {
 915             $qtypeswithextrafields[$qtype] = method_exists($qtypeclass, 'decode_content_links_caller');
 916             $qtypeswithhtmlanswers[$qtype] = $qtypeclass->has_html_answers();
 917         }
 918         $extraprocessing = array();
 919
 920         $coursemodulecontexts = array();
 921         $context = get_context_instance(CONTEXT_COURSE, $restore->course_id);
 922         $coursemodulecontexts[] = $context->id;
 923         $cms = get_records('course_modules', 'course', $restore->course_id, '', 'id');
 924         if ($cms){
 925             foreach ($cms as $cm){
 926                 $context =  get_context_instance(CONTEXT_MODULE, $cm->id);
 927                 $coursemodulecontexts[] = $context->id;
 928             }
 929         }
 930         $coursemodulecontextslist = join($coursemodulecontexts, ',');
 931         // Decode links in questions.
 932         if ($questions = get_records_sql('SELECT q.id, q.qtype, q.questiontext, q.generalfeedback '.
 933                  'FROM ' . $CFG->prefix . 'question q, '.
 934                  $CFG->prefix . 'question_categories qc '.
 935                  'WHERE q.category = qc.id '.
 936                  'AND qc.contextid IN (' .$coursemodulecontextslist.')')) {
 937
 938             foreach ($questions as $question) {
 939                 $questiontext = restore_decode_content_links_worker($question->questiontext, $restore);
 940                 $generalfeedback = restore_decode_content_links_worker($question->generalfeedback, $restore);
 941                 if ($questiontext != $question->questiontext || $generalfeedback != $question->generalfeedback) {
 942                     $question->questiontext = addslashes($questiontext);
 943                     $question->generalfeedback = addslashes($generalfeedback);
 944                     if (!update_record('question', $question)) {
 945                         $status = false;
 946                     }
 947                 }
 948
 949                 // Do some output.
 950                 if (++$i % 5 == 0 && !defined('RESTORE_SILENTLY')) {
 951                     echo ".";
 952                     if ($i % 100 == 0) {
 953                         echo "<br />";
 954                     }
 955                     backup_flush(300);
 956                 }
 957
 958                 // Decode any questiontype specific fields.
 959                 if ($qtypeswithextrafields[$question->qtype]) {
 960                     if (!array_key_exists($question->qtype, $extraprocessing)) {
 961                         $extraprocessing[$question->qtype] = array();
 962                     }
 963                     $extraprocessing[$question->qtype][] = $question->id;
 964                 }
 965             }
 966         }
 967
 968         // Decode links in answers.
 969         if ($answers = get_records_sql('SELECT qa.id, qa.answer, qa.feedback, q.qtype
 970                FROM ' . $CFG->prefix . 'question_answers qa,
 971                     ' . $CFG->prefix . 'question q,
 972                     ' . $CFG->prefix . 'question_categories qc
 973                WHERE qa.question = q.id
 974                  AND q.category = qc.id '.
 975                  'AND qc.contextid IN ('.$coursemodulecontextslist.')')) {
 976
 977             foreach ($answers as $answer) {
 978                 $feedback = restore_decode_content_links_worker($answer->feedback, $restore);
 979                 if ($qtypeswithhtmlanswers[$answer->qtype]) {
 980                     $answertext = restore_decode_content_links_worker($answer->answer, $restore);
 981                 } else {
 982                     $answertext = $answer->answer;
 983                 }
 984                 if ($feedback != $answer->feedback || $answertext != $answer->answer) {
 985                     unset($answer->qtype);
 986                     $answer->feedback = addslashes($feedback);
 987                     $answer->answer = addslashes($answertext);
 988                     if (!update_record('question_answers', $answer)) {
 989                         $status = false;
 990                     }
 991                 }
 992
 993                 // Do some output.
 994                 if (++$i % 5 == 0 && !defined('RESTORE_SILENTLY')) {
 995                     echo ".";
 996                     if ($i % 100 == 0) {
 997                         echo "<br />";
 998                     }
 999                     backup_flush(300);
1000                 }
1001             }
1002         }
1003
1004         // Do extra work for certain question types.
1005         foreach ($extraprocessing as $qtype => $questionids) {
1006             if (!$QTYPES[$qtype]->decode_content_links_caller($questionids, $restore, $i)) {
1007                 $status = false;
1008             }
1009         }
1010
1011         return $status;
1012     }
1013 ?>