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Differences Between: [Versions 310 and 400] [Versions 311 and 400] [Versions 39 and 400] [Versions 400 and 401] [Versions 400 and 402] [Versions 400 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  /**
  19   * Multianswer question definition class.
  20   *
  21   * @package    qtype
  22   * @subpackage multianswer
  23   * @copyright  2010 Pierre Pichet
  24   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25   */
  26  
  27  require_once($CFG->dirroot . '/question/type/questionbase.php');
  28  require_once($CFG->dirroot . '/question/type/shortanswer/question.php');
  29  require_once($CFG->dirroot . '/question/type/numerical/question.php');
  30  require_once($CFG->dirroot . '/question/type/multichoice/question.php');
  31  
  32  
  33  /**
  34   * Represents a multianswer question.
  35   *
  36   * A multi-answer question is made of of several subquestions of various types.
  37   * You can think of it as an application of the composite pattern to qusetion
  38   * types.
  39   *
  40   * @copyright  2010 Pierre Pichet
  41   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  42   */
  43  class qtype_multianswer_question extends question_graded_automatically_with_countback {
  44      /** @var array of question_graded_automatically. */
  45      public $subquestions = array();
  46  
  47      /**
  48       * @var array place number => insex in the $subquestions array. Places are
  49       * numbered from 1.
  50       */
  51      public $places;
  52  
  53      /**
  54       * @var array of strings, one longer than $places, which is achieved by
  55       * indexing from 0. The bits of question text that go between the subquestions.
  56       */
  57      public $textfragments;
  58  
  59      /**
  60       * Get a question_attempt_step_subquestion_adapter
  61       * @param question_attempt_step $step the step to adapt.
  62       * @param int $i the subquestion index.
  63       * @return question_attempt_step_subquestion_adapter.
  64       */
  65      protected function get_substep($step, $i) {
  66          return new question_attempt_step_subquestion_adapter($step, 'sub' . $i . '_');
  67      }
  68  
  69      public function start_attempt(question_attempt_step $step, $variant) {
  70          foreach ($this->subquestions as $i => $subq) {
  71              $subq->start_attempt($this->get_substep($step, $i), $variant);
  72          }
  73      }
  74  
  75      public function apply_attempt_state(question_attempt_step $step) {
  76          foreach ($this->subquestions as $i => $subq) {
  77              $subq->apply_attempt_state($this->get_substep($step, $i));
  78          }
  79      }
  80  
  81      public function validate_can_regrade_with_other_version(question_definition $otherversion): ?string {
  82          $basemessage = parent::validate_can_regrade_with_other_version($otherversion);
  83          if ($basemessage) {
  84              return $basemessage;
  85          }
  86  
  87          if (count($this->subquestions) != count($otherversion->subquestions)) {
  88              return get_string('regradeissuenumsubquestionschanged', 'qtype_multianswer');
  89          }
  90  
  91          foreach ($this->subquestions as $i => $subq) {
  92              $subqmessage = $subq->validate_can_regrade_with_other_version($otherversion->subquestions[$i]);
  93              if ($subqmessage) {
  94                  return $subqmessage;
  95              }
  96          }
  97  
  98          return null;
  99      }
 100  
 101      public function update_attempt_state_data_for_new_version(
 102              question_attempt_step $oldstep, question_definition $oldquestion) {
 103          parent::update_attempt_state_data_for_new_version($oldstep, $oldquestion);
 104  
 105          $result = [];
 106          foreach ($this->subquestions as $i => $subq) {
 107              $substep = $this->get_substep($oldstep, $i);
 108              $statedata = $subq->update_attempt_state_data_for_new_version(
 109                      $substep, $oldquestion->subquestions[$i]);
 110              foreach ($statedata as $name => $value) {
 111                  $result[$substep->add_prefix($name)] = $value;
 112              }
 113          }
 114  
 115          return $result;
 116      }
 117  
 118      public function get_question_summary() {
 119          $summary = $this->html_to_text($this->questiontext, $this->questiontextformat);
 120          foreach ($this->subquestions as $i => $subq) {
 121              switch ($subq->qtype->name()) {
 122                  case 'multichoice':
 123                      $choices = array();
 124                      $dummyqa = new question_attempt($subq, $this->contextid);
 125                      foreach ($subq->get_order($dummyqa) as $ansid) {
 126                          $choices[] = $this->html_to_text($subq->answers[$ansid]->answer,
 127                                  $subq->answers[$ansid]->answerformat);
 128                      }
 129                      $answerbit = '{' . implode('; ', $choices) . '}';
 130                      break;
 131                  case 'numerical':
 132                  case 'shortanswer':
 133                      $answerbit = '_____';
 134                      break;
 135                  default:
 136                      $answerbit = '{ERR unknown sub-question type}';
 137              }
 138              $summary = str_replace('{#' . $i . '}', $answerbit, $summary);
 139          }
 140          return $summary;
 141      }
 142  
 143      public function get_min_fraction() {
 144          $fractionsum = 0;
 145          $fractionmax = 0;
 146          foreach ($this->subquestions as $i => $subq) {
 147              $fractionmax += $subq->defaultmark;
 148              $fractionsum += $subq->defaultmark * $subq->get_min_fraction();
 149          }
 150          return $fractionsum / (!empty($this->subquestions) ? $fractionmax : 1);
 151      }
 152  
 153      public function get_max_fraction() {
 154          $fractionsum = 0;
 155          $fractionmax = 0;
 156          foreach ($this->subquestions as $i => $subq) {
 157              $fractionmax += $subq->defaultmark;
 158              $fractionsum += $subq->defaultmark * $subq->get_max_fraction();
 159          }
 160          return $fractionsum / (!empty($this->subquestions) ? $fractionmax : 1);
 161      }
 162  
 163      public function get_expected_data() {
 164          $expected = array();
 165          foreach ($this->subquestions as $i => $subq) {
 166              $substep = $this->get_substep(null, $i);
 167              foreach ($subq->get_expected_data() as $name => $type) {
 168                  if ($subq->qtype->name() == 'multichoice' &&
 169                          $subq->layout == qtype_multichoice_base::LAYOUT_DROPDOWN) {
 170                      // Hack or MC inline does not work.
 171                      $expected[$substep->add_prefix($name)] = PARAM_RAW;
 172                  } else {
 173                      $expected[$substep->add_prefix($name)] = $type;
 174                  }
 175              }
 176          }
 177          return $expected;
 178      }
 179  
 180      public function get_correct_response() {
 181          $right = array();
 182          foreach ($this->subquestions as $i => $subq) {
 183              $substep = $this->get_substep(null, $i);
 184              foreach ($subq->get_correct_response() as $name => $type) {
 185                  $right[$substep->add_prefix($name)] = $type;
 186              }
 187          }
 188          return $right;
 189      }
 190  
 191      public function prepare_simulated_post_data($simulatedresponse) {
 192          $postdata = array();
 193          foreach ($this->subquestions as $i => $subq) {
 194              $substep = $this->get_substep(null, $i);
 195              foreach ($subq->prepare_simulated_post_data($simulatedresponse[$i]) as $name => $value) {
 196                  $postdata[$substep->add_prefix($name)] = $value;
 197              }
 198          }
 199          return $postdata;
 200      }
 201  
 202      public function get_student_response_values_for_simulation($postdata) {
 203          $simulatedresponse = array();
 204          foreach ($this->subquestions as $i => $subq) {
 205              $substep = $this->get_substep(null, $i);
 206              $subqpostdata = $substep->filter_array($postdata);
 207              $subqsimulatedresponse = $subq->get_student_response_values_for_simulation($subqpostdata);
 208              foreach ($subqsimulatedresponse as $subresponsekey => $responsevalue) {
 209                  $simulatedresponse[$i.'.'.$subresponsekey] = $responsevalue;
 210              }
 211          }
 212          ksort($simulatedresponse);
 213          return $simulatedresponse;
 214      }
 215  
 216      public function is_complete_response(array $response) {
 217          foreach ($this->subquestions as $i => $subq) {
 218              $substep = $this->get_substep(null, $i);
 219              if (!$subq->is_complete_response($substep->filter_array($response))) {
 220                  return false;
 221              }
 222          }
 223          return true;
 224      }
 225  
 226      public function is_gradable_response(array $response) {
 227          foreach ($this->subquestions as $i => $subq) {
 228              $substep = $this->get_substep(null, $i);
 229              if ($subq->is_gradable_response($substep->filter_array($response))) {
 230                  return true;
 231              }
 232          }
 233          return false;
 234      }
 235  
 236      public function is_same_response(array $prevresponse, array $newresponse) {
 237          foreach ($this->subquestions as $i => $subq) {
 238              $substep = $this->get_substep(null, $i);
 239              if (!$subq->is_same_response($substep->filter_array($prevresponse),
 240                      $substep->filter_array($newresponse))) {
 241                  return false;
 242              }
 243          }
 244          return true;
 245      }
 246  
 247      public function get_validation_error(array $response) {
 248          if ($this->is_complete_response($response)) {
 249              return '';
 250          }
 251          return get_string('pleaseananswerallparts', 'qtype_multianswer');
 252      }
 253  
 254      /**
 255       * Used by grade_response to combine the states of the subquestions.
 256       * The combined state is accumulates in $overallstate. That will be right
 257       * if all the separate states are right; and wrong if all the separate states
 258       * are wrong, otherwise, it will be partially right.
 259       * @param question_state $overallstate the result so far.
 260       * @param question_state $newstate the new state to add to the combination.
 261       * @return question_state the new combined state.
 262       */
 263      protected function combine_states($overallstate, $newstate) {
 264          if (is_null($overallstate)) {
 265              return $newstate;
 266          } else if ($overallstate == question_state::$gaveup &&
 267                  $newstate == question_state::$gaveup) {
 268              return question_state::$gaveup;
 269          } else if ($overallstate == question_state::$gaveup &&
 270                  $newstate == question_state::$gradedwrong) {
 271              return question_state::$gradedwrong;
 272          } else if ($overallstate == question_state::$gradedwrong &&
 273                  $newstate == question_state::$gaveup) {
 274              return question_state::$gradedwrong;
 275          } else if ($overallstate == question_state::$gradedwrong &&
 276                  $newstate == question_state::$gradedwrong) {
 277              return question_state::$gradedwrong;
 278          } else if ($overallstate == question_state::$gradedright &&
 279                  $newstate == question_state::$gradedright) {
 280              return question_state::$gradedright;
 281          } else {
 282              return question_state::$gradedpartial;
 283          }
 284      }
 285  
 286      public function grade_response(array $response) {
 287          $overallstate = null;
 288          $fractionsum = 0;
 289          $fractionmax = 0;
 290          foreach ($this->subquestions as $i => $subq) {
 291              $fractionmax += $subq->defaultmark;
 292              $substep = $this->get_substep(null, $i);
 293              $subresp = $substep->filter_array($response);
 294              if (!$subq->is_gradable_response($subresp)) {
 295                  $overallstate = $this->combine_states($overallstate, question_state::$gaveup);
 296              } else {
 297                  list($subfraction, $newstate) = $subq->grade_response($subresp);
 298                  $fractionsum += $subfraction * $subq->defaultmark;
 299                  $overallstate = $this->combine_states($overallstate, $newstate);
 300              }
 301          }
 302          return array($fractionsum / $fractionmax, $overallstate);
 303      }
 304  
 305      public function clear_wrong_from_response(array $response) {
 306          foreach ($this->subquestions as $i => $subq) {
 307              $substep = $this->get_substep(null, $i);
 308              $subresp = $substep->filter_array($response);
 309              list($subfraction, $newstate) = $subq->grade_response($subresp);
 310              if ($newstate != question_state::$gradedright) {
 311                  foreach ($subresp as $ind => $resp) {
 312                      if ($subq->qtype == 'multichoice' && ($subq->layout == qtype_multichoice_base::LAYOUT_VERTICAL
 313                              || $subq->layout == qtype_multichoice_base::LAYOUT_HORIZONTAL)) {
 314                          $response[$substep->add_prefix($ind)] = '-1';
 315                      } else {
 316                          $response[$substep->add_prefix($ind)] = '';
 317                      }
 318                  }
 319              }
 320          }
 321          return $response;
 322      }
 323  
 324      public function get_num_parts_right(array $response) {
 325          $numright = 0;
 326          foreach ($this->subquestions as $i => $subq) {
 327              $substep = $this->get_substep(null, $i);
 328              $subresp = $substep->filter_array($response);
 329              list($subfraction, $newstate) = $subq->grade_response($subresp);
 330              if ($newstate == question_state::$gradedright) {
 331                  $numright += 1;
 332              }
 333          }
 334          return array($numright, count($this->subquestions));
 335      }
 336  
 337      public function compute_final_grade($responses, $totaltries) {
 338          $fractionsum = 0;
 339          $fractionmax = 0;
 340          foreach ($this->subquestions as $i => $subq) {
 341              $fractionmax += $subq->defaultmark;
 342  
 343              $lastresponse = array();
 344              $lastchange = 0;
 345              $subfraction = 0;
 346              foreach ($responses as $responseindex => $response) {
 347                  $substep = $this->get_substep(null, $i);
 348                  $subresp = $substep->filter_array($response);
 349                  if ($subq->is_same_response($lastresponse, $subresp)) {
 350                      continue;
 351                  }
 352                  $lastresponse = $subresp;
 353                  $lastchange = $responseindex;
 354                  list($subfraction, $newstate) = $subq->grade_response($subresp);
 355              }
 356  
 357              $fractionsum += $subq->defaultmark * max(0, $subfraction - $lastchange * $this->penalty);
 358          }
 359  
 360          return $fractionsum / $fractionmax;
 361      }
 362  
 363      public function summarise_response(array $response) {
 364          $summary = array();
 365          foreach ($this->subquestions as $i => $subq) {
 366              $substep = $this->get_substep(null, $i);
 367              $a = new stdClass();
 368              $a->i = $i;
 369              $a->response = $subq->summarise_response($substep->filter_array($response));
 370              $summary[] = get_string('subqresponse', 'qtype_multianswer', $a);
 371          }
 372  
 373          return implode('; ', $summary);
 374      }
 375  
 376      public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) {
 377          if ($component == 'question' && $filearea == 'answer') {
 378              return true;
 379  
 380          } else if ($component == 'question' && $filearea == 'answerfeedback') {
 381              // Full logic to control which feedbacks a student can see is too complex.
 382              // Just allow access to all images. There is a theoretical chance the
 383              // students could see files they are not meant to see by guessing URLs,
 384              // but it is remote.
 385              return $options->feedback;
 386  
 387          } else if ($component == 'question' && $filearea == 'hint') {
 388              return $this->check_hint_file_access($qa, $options, $args);
 389  
 390          } else {
 391              return parent::check_file_access($qa, $options, $component, $filearea,
 392                      $args, $forcedownload);
 393          }
 394      }
 395  
 396      /**
 397       * Return the question settings that define this question as structured data.
 398       *
 399       * @param question_attempt $qa the current attempt for which we are exporting the settings.
 400       * @param question_display_options $options the question display options which say which aspects of the question
 401       * should be visible.
 402       * @return mixed structure representing the question settings. In web services, this will be JSON-encoded.
 403       */
 404      public function get_question_definition_for_external_rendering(question_attempt $qa, question_display_options $options) {
 405          // Empty implementation for now in order to avoid debugging in core questions (generated in the parent class),
 406          // ideally, we should return as much as settings as possible (depending on the state and display options).
 407  
 408          return null;
 409      }
 410  }