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Differences Between: [Versions 310 and 402] [Versions 311 and 402] [Versions 39 and 402]

   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   * Matching question definition class.
  19   *
  20   * @package   qtype_match
  21   * @copyright 2009 The Open University
  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 . '/question/type/questionbase.php');
  29  
  30  /**
  31   * Represents a matching question.
  32   *
  33   * @copyright 2009 The Open University
  34   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  35   */
  36  class qtype_match_question extends question_graded_automatically_with_countback {
  37      /** @var boolean Whether the question stems should be shuffled. */
  38      public $shufflestems;
  39  
  40      public $correctfeedback;
  41      public $correctfeedbackformat;
  42      public $partiallycorrectfeedback;
  43      public $partiallycorrectfeedbackformat;
  44      public $incorrectfeedback;
  45      public $incorrectfeedbackformat;
  46  
  47      /** @var array of question stems. */
  48      public $stems;
  49      /** @var int[] FORMAT_... type for each stem. */
  50      public $stemformat;
  51      /** @var array of choices that can be matched to each stem. */
  52      public $choices;
  53      /** @var array index of the right choice for each stem. */
  54      public $right;
  55  
  56      /** @var array shuffled stem indexes. */
  57      protected $stemorder;
  58      /** @var array shuffled choice indexes. */
  59      protected $choiceorder;
  60  
  61      public function start_attempt(question_attempt_step $step, $variant) {
  62          $this->stemorder = array_keys($this->stems);
  63          if ($this->shufflestems) {
  64              shuffle($this->stemorder);
  65          }
  66          $step->set_qt_var('_stemorder', implode(',', $this->stemorder));
  67  
  68          $choiceorder = array_keys($this->choices);
  69          shuffle($choiceorder);
  70          $step->set_qt_var('_choiceorder', implode(',', $choiceorder));
  71          $this->set_choiceorder($choiceorder);
  72      }
  73  
  74      public function apply_attempt_state(question_attempt_step $step) {
  75          $this->stemorder = explode(',', $step->get_qt_var('_stemorder'));
  76          $this->set_choiceorder(explode(',', $step->get_qt_var('_choiceorder')));
  77  
  78          // Add any missing subquestions. Sometimes people edit questions after they
  79          // have been attempted which breaks things.
  80          foreach ($this->stemorder as $stemid) {
  81              if (!isset($this->stems[$stemid])) {
  82                  $this->stems[$stemid] = html_writer::span(
  83                          get_string('deletedsubquestion', 'qtype_match'), 'notifyproblem');
  84                  $this->stemformat[$stemid] = FORMAT_HTML;
  85                  $this->right[$stemid] = 0;
  86              }
  87          }
  88  
  89          // Add any missing choices. Sometimes people edit questions after they
  90          // have been attempted which breaks things.
  91          foreach ($this->choiceorder as $choiceid) {
  92              if (!isset($this->choices[$choiceid])) {
  93                  $this->choices[$choiceid] = get_string('deletedchoice', 'qtype_match');
  94              }
  95          }
  96      }
  97  
  98      /**
  99       * Helper method used by both {@link start_attempt()} and
 100       * {@link apply_attempt_state()}.
 101       * @param array $choiceorder the choices, in order.
 102       */
 103      protected function set_choiceorder($choiceorder) {
 104          $this->choiceorder = array();
 105          foreach ($choiceorder as $key => $choiceid) {
 106              $this->choiceorder[$key + 1] = $choiceid;
 107          }
 108      }
 109  
 110      public function validate_can_regrade_with_other_version(question_definition $otherversion): ?string {
 111          $basemessage = parent::validate_can_regrade_with_other_version($otherversion);
 112          if ($basemessage) {
 113              return $basemessage;
 114          }
 115  
 116          if (count($this->stems) != count($otherversion->stems)) {
 117              return get_string('regradeissuenumstemschanged', 'qtype_match');
 118          }
 119  
 120          if (count($this->choices) != count($otherversion->choices)) {
 121              return get_string('regradeissuenumchoiceschanged', 'qtype_match');
 122          }
 123  
 124          return null;
 125      }
 126  
 127      public function update_attempt_state_data_for_new_version(
 128              question_attempt_step $oldstep, question_definition $otherversion) {
 129          $startdata = parent::update_attempt_state_data_for_new_version($oldstep, $otherversion);
 130  
 131          // Process stems.
 132          $mapping = array_combine(array_keys($otherversion->stems), array_keys($this->stems));
 133          $oldstemorder = explode(',', $oldstep->get_qt_var('_stemorder'));
 134          $newstemorder = [];
 135          foreach ($oldstemorder as $oldid) {
 136              $newstemorder[] = $mapping[$oldid] ?? $oldid;
 137          }
 138          $startdata['_stemorder'] = implode(',', $newstemorder);
 139  
 140          // Process choices.
 141          $mapping = array_combine(array_keys($otherversion->choices), array_keys($this->choices));
 142          $oldchoiceorder = explode(',', $oldstep->get_qt_var('_choiceorder'));
 143          $newchoiceorder = [];
 144          foreach ($oldchoiceorder as $oldid) {
 145              $newchoiceorder[] = $mapping[$oldid] ?? $oldid;
 146          }
 147          $startdata['_choiceorder'] = implode(',', $newchoiceorder);
 148  
 149          return $startdata;
 150      }
 151  
 152      public function get_question_summary() {
 153          $question = $this->html_to_text($this->questiontext, $this->questiontextformat);
 154          $stems = array();
 155          foreach ($this->stemorder as $stemid) {
 156              $stems[] = $this->html_to_text($this->stems[$stemid], $this->stemformat[$stemid]);
 157          }
 158          $choices = array();
 159          foreach ($this->choiceorder as $choiceid) {
 160              $choices[] = $this->choices[$choiceid];
 161          }
 162          return $question . ' {' . implode('; ', $stems) . '} -> {' .
 163                  implode('; ', $choices) . '}';
 164      }
 165  
 166      public function summarise_response(array $response) {
 167          $matches = array();
 168          foreach ($this->stemorder as $key => $stemid) {
 169              if (array_key_exists($this->field($key), $response) && $response[$this->field($key)]) {
 170                  $matches[] = $this->html_to_text($this->stems[$stemid],
 171                          $this->stemformat[$stemid]) . ' -> ' .
 172                          $this->choices[$this->choiceorder[$response[$this->field($key)]]];
 173              }
 174          }
 175          if (empty($matches)) {
 176              return null;
 177          }
 178          return implode('; ', $matches);
 179      }
 180  
 181      public function classify_response(array $response) {
 182          $selectedchoicekeys = array();
 183          foreach ($this->stemorder as $key => $stemid) {
 184              if (array_key_exists($this->field($key), $response) && $response[$this->field($key)]) {
 185                  $selectedchoicekeys[$stemid] = $this->choiceorder[$response[$this->field($key)]];
 186              } else {
 187                  $selectedchoicekeys[$stemid] = 0;
 188              }
 189          }
 190  
 191          $parts = array();
 192          foreach ($this->stems as $stemid => $stem) {
 193              if ($this->right[$stemid] == 0 || !isset($selectedchoicekeys[$stemid])) {
 194                  // Choice for a deleted subquestion, ignore. (See apply_attempt_state.)
 195                  continue;
 196              }
 197              $selectedchoicekey = $selectedchoicekeys[$stemid];
 198              if (empty($selectedchoicekey)) {
 199                  $parts[$stemid] = question_classified_response::no_response();
 200                  continue;
 201              }
 202              $choice = $this->choices[$selectedchoicekey];
 203              if ($choice == get_string('deletedchoice', 'qtype_match')) {
 204                  // Deleted choice, ignore. (See apply_attempt_state.)
 205                  continue;
 206              }
 207              $parts[$stemid] = new question_classified_response(
 208                      $selectedchoicekey, $choice,
 209                      ($selectedchoicekey == $this->right[$stemid]) / count($this->stems));
 210          }
 211          return $parts;
 212      }
 213  
 214      public function clear_wrong_from_response(array $response) {
 215          foreach ($this->stemorder as $key => $stemid) {
 216              if (!array_key_exists($this->field($key), $response) ||
 217                      $response[$this->field($key)] != $this->get_right_choice_for($stemid)) {
 218                  $response[$this->field($key)] = 0;
 219              }
 220          }
 221          return $response;
 222      }
 223  
 224      public function get_num_parts_right(array $response) {
 225          $numright = 0;
 226          foreach ($this->stemorder as $key => $stemid) {
 227              $fieldname = $this->field($key);
 228              if (!array_key_exists($fieldname, $response)) {
 229                  continue;
 230              }
 231  
 232              $choice = $response[$fieldname];
 233              if ($choice && $this->choiceorder[$choice] == $this->right[$stemid]) {
 234                  $numright += 1;
 235              }
 236          }
 237          return array($numright, count($this->stemorder));
 238      }
 239  
 240      /**
 241       * @param int $key stem number
 242       * @return string the question-type variable name.
 243       */
 244      protected function field($key) {
 245          return 'sub' . $key;
 246      }
 247  
 248      public function get_expected_data() {
 249          $vars = array();
 250          foreach ($this->stemorder as $key => $notused) {
 251              $vars[$this->field($key)] = PARAM_INT;
 252          }
 253          return $vars;
 254      }
 255  
 256      public function get_correct_response() {
 257          $response = array();
 258          foreach ($this->stemorder as $key => $stemid) {
 259              $response[$this->field($key)] = $this->get_right_choice_for($stemid);
 260          }
 261          return $response;
 262      }
 263  
 264      public function prepare_simulated_post_data($simulatedresponse) {
 265          $postdata = array();
 266          $stemtostemids = array_flip(clean_param_array($this->stems, PARAM_NOTAGS));
 267          $choicetochoiceno = array_flip($this->choices);
 268          $choicenotochoiceselectvalue = array_flip($this->choiceorder);
 269          foreach ($simulatedresponse as $stem => $choice) {
 270              $choice = clean_param($choice, PARAM_NOTAGS);
 271              $stemid = $stemtostemids[$stem];
 272              $shuffledstemno = array_search($stemid, $this->stemorder);
 273              if (empty($choice)) {
 274                  $choiceselectvalue = 0;
 275              } else if ($choicetochoiceno[$choice]) {
 276                  $choiceselectvalue = $choicenotochoiceselectvalue[$choicetochoiceno[$choice]];
 277              } else {
 278                  throw new coding_exception("Unknown choice {$choice} in matching question - {$this->name}.");
 279              }
 280              $postdata[$this->field($shuffledstemno)] = $choiceselectvalue;
 281          }
 282          return $postdata;
 283      }
 284  
 285      public function get_student_response_values_for_simulation($postdata) {
 286          $simulatedresponse = array();
 287          foreach ($this->stemorder as $shuffledstemno => $stemid) {
 288              if (!empty($postdata[$this->field($shuffledstemno)])) {
 289                  $choiceselectvalue = $postdata[$this->field($shuffledstemno)];
 290                  $choiceno = $this->choiceorder[$choiceselectvalue];
 291                  $choice = clean_param($this->choices[$choiceno], PARAM_NOTAGS);
 292                  $stem = clean_param($this->stems[$stemid], PARAM_NOTAGS);
 293                  $simulatedresponse[$stem] = $choice;
 294              }
 295          }
 296          ksort($simulatedresponse);
 297          return $simulatedresponse;
 298      }
 299  
 300      public function get_right_choice_for($stemid) {
 301          foreach ($this->choiceorder as $choicekey => $choiceid) {
 302              if ($this->right[$stemid] == $choiceid) {
 303                  return $choicekey;
 304              }
 305          }
 306      }
 307  
 308      public function is_complete_response(array $response) {
 309          $complete = true;
 310          foreach ($this->stemorder as $key => $stemid) {
 311              $complete = $complete && !empty($response[$this->field($key)]);
 312          }
 313          return $complete;
 314      }
 315  
 316      public function is_gradable_response(array $response) {
 317          foreach ($this->stemorder as $key => $stemid) {
 318              if (!empty($response[$this->field($key)])) {
 319                  return true;
 320              }
 321          }
 322          return false;
 323      }
 324  
 325      public function get_validation_error(array $response) {
 326          if ($this->is_complete_response($response)) {
 327              return '';
 328          }
 329          return get_string('pleaseananswerallparts', 'qtype_match');
 330      }
 331  
 332      public function is_same_response(array $prevresponse, array $newresponse) {
 333          foreach ($this->stemorder as $key => $notused) {
 334              $fieldname = $this->field($key);
 335              if (!question_utils::arrays_same_at_key_integer(
 336                      $prevresponse, $newresponse, $fieldname)) {
 337                  return false;
 338              }
 339          }
 340          return true;
 341      }
 342  
 343      public function grade_response(array $response) {
 344          list($right, $total) = $this->get_num_parts_right($response);
 345          $fraction = $right / $total;
 346          return array($fraction, question_state::graded_state_for_fraction($fraction));
 347      }
 348  
 349      public function compute_final_grade($responses, $totaltries) {
 350          $totalstemscore = 0;
 351          foreach ($this->stemorder as $key => $stemid) {
 352              $fieldname = $this->field($key);
 353  
 354              $lastwrongindex = -1;
 355              $finallyright = false;
 356              foreach ($responses as $i => $response) {
 357                  if (!array_key_exists($fieldname, $response) || !$response[$fieldname] ||
 358                          $this->choiceorder[$response[$fieldname]] != $this->right[$stemid]) {
 359                      $lastwrongindex = $i;
 360                      $finallyright = false;
 361                  } else {
 362                      $finallyright = true;
 363                  }
 364              }
 365  
 366              if ($finallyright) {
 367                  $totalstemscore += max(0, 1 - ($lastwrongindex + 1) * $this->penalty);
 368              }
 369          }
 370  
 371          return $totalstemscore / count($this->stemorder);
 372      }
 373  
 374      public function get_stem_order() {
 375          return $this->stemorder;
 376      }
 377  
 378      public function get_choice_order() {
 379          return $this->choiceorder;
 380      }
 381  
 382      public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) {
 383          if ($component == 'qtype_match' && $filearea == 'subquestion') {
 384              $subqid = reset($args); // Itemid is sub question id.
 385              return array_key_exists($subqid, $this->stems);
 386  
 387          } else if ($component == 'question' && in_array($filearea,
 388                  array('correctfeedback', 'partiallycorrectfeedback', 'incorrectfeedback'))) {
 389              return $this->check_combined_feedback_file_access($qa, $options, $filearea, $args);
 390  
 391          } else if ($component == 'question' && $filearea == 'hint') {
 392              return $this->check_hint_file_access($qa, $options, $args);
 393  
 394          } else {
 395              return parent::check_file_access($qa, $options, $component, $filearea,
 396                      $args, $forcedownload);
 397          }
 398      }
 399  
 400      /**
 401       * Return the question settings that define this question as structured data.
 402       *
 403       * @param question_attempt $qa the current attempt for which we are exporting the settings.
 404       * @param question_display_options $options the question display options which say which aspects of the question
 405       * should be visible.
 406       * @return mixed structure representing the question settings. In web services, this will be JSON-encoded.
 407       */
 408      public function get_question_definition_for_external_rendering(question_attempt $qa, question_display_options $options) {
 409          // This is a partial implementation, returning only the most relevant question settings for now,
 410          // ideally, we should return as much as settings as possible (depending on the state and display options).
 411  
 412          return [
 413              'shufflestems' => $this->shufflestems,
 414          ];
 415      }
 416  }