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

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Helper functions for the quiz reports.
  19   *
  20   * @package   mod_quiz
  21   * @copyright 2008 Jamie Pratt
  22   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  
  26  defined('MOODLE_INTERNAL') || die();
  27  
  28  require_once($CFG->dirroot . '/mod/quiz/lib.php');
  29  require_once($CFG->libdir . '/filelib.php');
  30  
  31  /**
  32   * Takes an array of objects and constructs a multidimensional array keyed by
  33   * the keys it finds on the object.
  34   * @param array $datum an array of objects with properties on the object
  35   * including the keys passed as the next param.
  36   * @param array $keys Array of strings with the names of the properties on the
  37   * objects in datum that you want to index the multidimensional array by.
  38   * @param bool $keysunique If there is not only one object for each
  39   * combination of keys you are using you should set $keysunique to true.
  40   * Otherwise all the object will be added to a zero based array. So the array
  41   * returned will have count($keys) + 1 indexs.
  42   * @return array multidimensional array properly indexed.
  43   */
  44  function quiz_report_index_by_keys($datum, $keys, $keysunique = true) {
  45      if (!$datum) {
  46          return array();
  47      }
  48      $key = array_shift($keys);
  49      $datumkeyed = array();
  50      foreach ($datum as $data) {
  51          if ($keys || !$keysunique) {
  52              $datumkeyed[$data->{$key}][]= $data;
  53          } else {
  54              $datumkeyed[$data->{$key}]= $data;
  55          }
  56      }
  57      if ($keys) {
  58          foreach ($datumkeyed as $datakey => $datakeyed) {
  59              $datumkeyed[$datakey] = quiz_report_index_by_keys($datakeyed, $keys, $keysunique);
  60          }
  61      }
  62      return $datumkeyed;
  63  }
  64  
  65  function quiz_report_unindex($datum) {
  66      if (!$datum) {
  67          return $datum;
  68      }
  69      $datumunkeyed = array();
  70      foreach ($datum as $value) {
  71          if (is_array($value)) {
  72              $datumunkeyed = array_merge($datumunkeyed, quiz_report_unindex($value));
  73          } else {
  74              $datumunkeyed[] = $value;
  75          }
  76      }
  77      return $datumunkeyed;
  78  }
  79  
  80  /**
  81   * Are there any questions in this quiz?
  82   * @param int $quizid the quiz id.
  83   */
  84  function quiz_has_questions($quizid) {
  85      global $DB;
  86      return $DB->record_exists('quiz_slots', array('quizid' => $quizid));
  87  }
  88  
  89  /**
  90   * Get the slots of real questions (not descriptions) in this quiz, in order.
  91   * @param object $quiz the quiz.
  92   * @return array of slot => $question object with fields
  93   *      ->slot, ->id, ->maxmark, ->number, ->length.
  94   */
  95  function quiz_report_get_significant_questions($quiz) {
  96      global $DB;
  97  
  98      $qsbyslot = $DB->get_records_sql("
  99              SELECT slot.slot,
 100                     q.id,
 101                     q.qtype,
 102                     q.length,
 103                     slot.maxmark
 104  
 105                FROM {question} q
 106                JOIN {quiz_slots} slot ON slot.questionid = q.id
 107  
 108               WHERE slot.quizid = ?
 109                 AND q.length > 0
 110  
 111            ORDER BY slot.slot", array($quiz->id));
 112  
 113      $number = 1;
 114      foreach ($qsbyslot as $question) {
 115          $question->number = $number;
 116          $number += $question->length;
 117          $question->type = $question->qtype;
 118      }
 119  
 120      return $qsbyslot;
 121  }
 122  
 123  /**
 124   * @param object $quiz the quiz settings.
 125   * @return bool whether, for this quiz, it is possible to filter attempts to show
 126   *      only those that gave the final grade.
 127   */
 128  function quiz_report_can_filter_only_graded($quiz) {
 129      return $quiz->attempts != 1 && $quiz->grademethod != QUIZ_GRADEAVERAGE;
 130  }
 131  
 132  /**
 133   * This is a wrapper for {@link quiz_report_grade_method_sql} that takes the whole quiz object instead of just the grading method
 134   * as a param. See definition for {@link quiz_report_grade_method_sql} below.
 135   *
 136   * @param object $quiz
 137   * @param string $quizattemptsalias sql alias for 'quiz_attempts' table
 138   * @return string sql to test if this is an attempt that will contribute towards the grade of the user
 139   */
 140  function quiz_report_qm_filter_select($quiz, $quizattemptsalias = 'quiza') {
 141      if ($quiz->attempts == 1) {
 142          // This quiz only allows one attempt.
 143          return '';
 144      }
 145      return quiz_report_grade_method_sql($quiz->grademethod, $quizattemptsalias);
 146  }
 147  
 148  /**
 149   * Given a quiz grading method return sql to test if this is an
 150   * attempt that will be contribute towards the grade of the user. Or return an
 151   * empty string if the grading method is QUIZ_GRADEAVERAGE and thus all attempts
 152   * contribute to final grade.
 153   *
 154   * @param string $grademethod quiz grading method.
 155   * @param string $quizattemptsalias sql alias for 'quiz_attempts' table
 156   * @return string sql to test if this is an attempt that will contribute towards the graded of the user
 157   */
 158  function quiz_report_grade_method_sql($grademethod, $quizattemptsalias = 'quiza') {
 159      switch ($grademethod) {
 160          case QUIZ_GRADEHIGHEST :
 161              return "($quizattemptsalias.state = 'finished' AND NOT EXISTS (
 162                             SELECT 1 FROM {quiz_attempts} qa2
 163                              WHERE qa2.quiz = $quizattemptsalias.quiz AND
 164                                  qa2.userid = $quizattemptsalias.userid AND
 165                                   qa2.state = 'finished' AND (
 166                  COALESCE(qa2.sumgrades, 0) > COALESCE($quizattemptsalias.sumgrades, 0) OR
 167                 (COALESCE(qa2.sumgrades, 0) = COALESCE($quizattemptsalias.sumgrades, 0) AND qa2.attempt < $quizattemptsalias.attempt)
 168                                  )))";
 169  
 170          case QUIZ_GRADEAVERAGE :
 171              return '';
 172  
 173          case QUIZ_ATTEMPTFIRST :
 174              return "($quizattemptsalias.state = 'finished' AND NOT EXISTS (
 175                             SELECT 1 FROM {quiz_attempts} qa2
 176                              WHERE qa2.quiz = $quizattemptsalias.quiz AND
 177                                  qa2.userid = $quizattemptsalias.userid AND
 178                                   qa2.state = 'finished' AND
 179                                 qa2.attempt < $quizattemptsalias.attempt))";
 180  
 181          case QUIZ_ATTEMPTLAST :
 182              return "($quizattemptsalias.state = 'finished' AND NOT EXISTS (
 183                             SELECT 1 FROM {quiz_attempts} qa2
 184                              WHERE qa2.quiz = $quizattemptsalias.quiz AND
 185                                  qa2.userid = $quizattemptsalias.userid AND
 186                                   qa2.state = 'finished' AND
 187                                 qa2.attempt > $quizattemptsalias.attempt))";
 188      }
 189  }
 190  
 191  /**
 192   * Get the number of students whose score was in a particular band for this quiz.
 193   * @param number $bandwidth the width of each band.
 194   * @param int $bands the number of bands
 195   * @param int $quizid the quiz id.
 196   * @param \core\dml\sql_join $usersjoins (joins, wheres, params) to get enrolled users
 197   * @return array band number => number of users with scores in that band.
 198   */
 199  function quiz_report_grade_bands($bandwidth, $bands, $quizid, \core\dml\sql_join $usersjoins = null) {
 200      global $DB;
 201      if (!is_int($bands)) {
 202          debugging('$bands passed to quiz_report_grade_bands must be an integer. (' .
 203                  gettype($bands) . ' passed.)', DEBUG_DEVELOPER);
 204          $bands = (int) $bands;
 205      }
 206  
 207      if ($usersjoins && !empty($usersjoins->joins)) {
 208          $userjoin = "JOIN {user} u ON u.id = qg.userid
 209                  {$usersjoins->joins}";
 210          $usertest = $usersjoins->wheres;
 211          $params = $usersjoins->params;
 212      } else {
 213          $userjoin = '';
 214          $usertest = '1=1';
 215          $params = array();
 216      }
 217      $sql = "
 218  SELECT band, COUNT(1)
 219  
 220  FROM (
 221      SELECT FLOOR(qg.grade / :bandwidth) AS band
 222        FROM {quiz_grades} qg
 223      $userjoin
 224      WHERE $usertest AND qg.quiz = :quizid
 225  ) subquery
 226  
 227  GROUP BY
 228      band
 229  
 230  ORDER BY
 231      band";
 232  
 233      $params['quizid'] = $quizid;
 234      $params['bandwidth'] = $bandwidth;
 235  
 236      $data = $DB->get_records_sql_menu($sql, $params);
 237  
 238      // We need to create array elements with values 0 at indexes where there is no element.
 239      $data = $data + array_fill(0, $bands + 1, 0);
 240      ksort($data);
 241  
 242      // Place the maximum (perfect grade) into the last band i.e. make last
 243      // band for example 9 <= g <=10 (where 10 is the perfect grade) rather than
 244      // just 9 <= g <10.
 245      $data[$bands - 1] += $data[$bands];
 246      unset($data[$bands]);
 247  
 248      return $data;
 249  }
 250  
 251  function quiz_report_highlighting_grading_method($quiz, $qmsubselect, $qmfilter) {
 252      if ($quiz->attempts == 1) {
 253          return '<p>' . get_string('onlyoneattemptallowed', 'quiz_overview') . '</p>';
 254  
 255      } else if (!$qmsubselect) {
 256          return '<p>' . get_string('allattemptscontributetograde', 'quiz_overview') . '</p>';
 257  
 258      } else if ($qmfilter) {
 259          return '<p>' . get_string('showinggraded', 'quiz_overview') . '</p>';
 260  
 261      } else {
 262          return '<p>' . get_string('showinggradedandungraded', 'quiz_overview',
 263                  '<span class="gradedattempt">' . quiz_get_grading_option_name($quiz->grademethod) .
 264                  '</span>') . '</p>';
 265      }
 266  }
 267  
 268  /**
 269   * Get the feedback text for a grade on this quiz. The feedback is
 270   * processed ready for display.
 271   *
 272   * @param float $grade a grade on this quiz.
 273   * @param int $quizid the id of the quiz object.
 274   * @return string the comment that corresponds to this grade (empty string if there is not one.
 275   */
 276  function quiz_report_feedback_for_grade($grade, $quizid, $context) {
 277      global $DB;
 278  
 279      static $feedbackcache = array();
 280  
 281      if (!isset($feedbackcache[$quizid])) {
 282          $feedbackcache[$quizid] = $DB->get_records('quiz_feedback', array('quizid' => $quizid));
 283      }
 284  
 285      // With CBM etc, it is possible to get -ve grades, which would then not match
 286      // any feedback. Therefore, we replace -ve grades with 0.
 287      $grade = max($grade, 0);
 288  
 289      $feedbacks = $feedbackcache[$quizid];
 290      $feedbackid = 0;
 291      $feedbacktext = '';
 292      $feedbacktextformat = FORMAT_MOODLE;
 293      foreach ($feedbacks as $feedback) {
 294          if ($feedback->mingrade <= $grade && $grade < $feedback->maxgrade) {
 295              $feedbackid = $feedback->id;
 296              $feedbacktext = $feedback->feedbacktext;
 297              $feedbacktextformat = $feedback->feedbacktextformat;
 298              break;
 299          }
 300      }
 301  
 302      // Clean the text, ready for display.
 303      $formatoptions = new stdClass();
 304      $formatoptions->noclean = true;
 305      $feedbacktext = file_rewrite_pluginfile_urls($feedbacktext, 'pluginfile.php',
 306              $context->id, 'mod_quiz', 'feedback', $feedbackid);
 307      $feedbacktext = format_text($feedbacktext, $feedbacktextformat, $formatoptions);
 308  
 309      return $feedbacktext;
 310  }
 311  
 312  /**
 313   * Format a number as a percentage out of $quiz->sumgrades
 314   * @param number $rawgrade the mark to format.
 315   * @param object $quiz the quiz settings
 316   * @param bool $round whether to round the results ot $quiz->decimalpoints.
 317   */
 318  function quiz_report_scale_summarks_as_percentage($rawmark, $quiz, $round = true) {
 319      if ($quiz->sumgrades == 0) {
 320          return '';
 321      }
 322      if (!is_numeric($rawmark)) {
 323          return $rawmark;
 324      }
 325  
 326      $mark = $rawmark * 100 / $quiz->sumgrades;
 327      if ($round) {
 328          $mark = quiz_format_grade($quiz, $mark);
 329      }
 330  
 331      return get_string('percents', 'moodle', $mark);
 332  }
 333  
 334  /**
 335   * Returns an array of reports to which the current user has access to.
 336   * @return array reports are ordered as they should be for display in tabs.
 337   */
 338  function quiz_report_list($context) {
 339      global $DB;
 340      static $reportlist = null;
 341      if (!is_null($reportlist)) {
 342          return $reportlist;
 343      }
 344  
 345      $reports = $DB->get_records('quiz_reports', null, 'displayorder DESC', 'name, capability');
 346      $reportdirs = core_component::get_plugin_list('quiz');
 347  
 348      // Order the reports tab in descending order of displayorder.
 349      $reportcaps = array();
 350      foreach ($reports as $key => $report) {
 351          if (array_key_exists($report->name, $reportdirs)) {
 352              $reportcaps[$report->name] = $report->capability;
 353          }
 354      }
 355  
 356      // Add any other reports, which are on disc but not in the DB, on the end.
 357      foreach ($reportdirs as $reportname => $notused) {
 358          if (!isset($reportcaps[$reportname])) {
 359              $reportcaps[$reportname] = null;
 360          }
 361      }
 362      $reportlist = array();
 363      foreach ($reportcaps as $name => $capability) {
 364          if (empty($capability)) {
 365              $capability = 'mod/quiz:viewreports';
 366          }
 367          if (has_capability($capability, $context)) {
 368              $reportlist[] = $name;
 369          }
 370      }
 371      return $reportlist;
 372  }
 373  
 374  /**
 375   * Create a filename for use when downloading data from a quiz report. It is
 376   * expected that this will be passed to flexible_table::is_downloading, which
 377   * cleans the filename of bad characters and adds the file extension.
 378   * @param string $report the type of report.
 379   * @param string $courseshortname the course shortname.
 380   * @param string $quizname the quiz name.
 381   * @return string the filename.
 382   */
 383  function quiz_report_download_filename($report, $courseshortname, $quizname) {
 384      return $courseshortname . '-' . format_string($quizname, true) . '-' . $report;
 385  }
 386  
 387  /**
 388   * Get the default report for the current user.
 389   * @param object $context the quiz context.
 390   */
 391  function quiz_report_default_report($context) {
 392      $reports = quiz_report_list($context);
 393      return reset($reports);
 394  }
 395  
 396  /**
 397   * Generate a message saying that this quiz has no questions, with a button to
 398   * go to the edit page, if the user has the right capability.
 399   * @param object $quiz the quiz settings.
 400   * @param object $cm the course_module object.
 401   * @param object $context the quiz context.
 402   * @return string HTML to output.
 403   */
 404  function quiz_no_questions_message($quiz, $cm, $context) {
 405      global $OUTPUT;
 406  
 407      $output = '';
 408      $output .= $OUTPUT->notification(get_string('noquestions', 'quiz'));
 409      if (has_capability('mod/quiz:manage', $context)) {
 410          $output .= $OUTPUT->single_button(new moodle_url('/mod/quiz/edit.php',
 411          array('cmid' => $cm->id)), get_string('editquiz', 'quiz'), 'get');
 412      }
 413  
 414      return $output;
 415  }
 416  
 417  /**
 418   * Should the grades be displayed in this report. That depends on the quiz
 419   * display options, and whether the quiz is graded.
 420   * @param object $quiz the quiz settings.
 421   * @param context $context the quiz context.
 422   * @return bool
 423   */
 424  function quiz_report_should_show_grades($quiz, context $context) {
 425      if ($quiz->timeclose && time() > $quiz->timeclose) {
 426          $when = mod_quiz_display_options::AFTER_CLOSE;
 427      } else {
 428          $when = mod_quiz_display_options::LATER_WHILE_OPEN;
 429      }
 430      $reviewoptions = mod_quiz_display_options::make_from_quiz($quiz, $when);
 431  
 432      return quiz_has_grades($quiz) &&
 433              ($reviewoptions->marks >= question_display_options::MARK_AND_MAX ||
 434              has_capability('moodle/grade:viewhidden', $context));
 435  }