quiz_question.module in Quiz 7.6

Quiz Question module. This module provides the basic facilities for adding quiz question types to a quiz.

File

question_types/quiz_question/quiz_question.module

<?php

/**
 * Quiz Question module.
 * This module provides the basic facilities for adding quiz question types to a quiz.
 * @file
 */

/**
 * Implements hook_help().
 */
function quiz_question_help($path, $args) {
  if ($path == 'admin/help#quiz_quesion') {
    return t('Support for Quiz question types.');
  }
}

/**
 * Implements hook_menu().
 */
function quiz_question_menu() {
  $items = array();
  $items['node/%/question-revision-actions'] = array(
    'title' => 'Revision actions',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'quiz_question_revision_actions_form',
      1,
    ),
    'access arguments' => array(
      'manual quiz revisioning',
    ),
    'file' => 'quiz_question.pages.inc',
    'type' => MENU_NORMAL_ITEM,
  );

  // Menu items for admin view of each question type.
  $items['admin/quiz/settings/questions_settings'] = array(
    'title' => 'Question configuration',
    'description' => 'Configure the question types.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'quiz_question_config',
    ),
    'access arguments' => array(
      'administer quiz configuration',
    ),
    'type' => MENU_NORMAL_ITEM,
  );
  return $items;
}

/**
 * Implements hook_theme().
 */
function quiz_question_theme() {
  $hooks = array(
    'quiz_question_creation_form' => array(
      'render element' => 'form',
      'file' => 'quiz_question.theme.inc',
    ),
    'quiz_question_navigation_form' => array(
      'render element' => 'form',
      'file' => 'quiz_question.theme.inc',
    ),
  );
  $hooks['quiz_question_feedback'] = array(
    'variables' => NULL,
    'pattern' => 'quiz_question_feedback__',
  );
  return $hooks;
}

/**
 * Implements hook_node_info().
 */
function quiz_question_node_info() {
  $node_info = array();
  foreach (quiz_question_get_info(NULL, TRUE) as $type => $definition) {
    if (!isset($definition['node']) || $definition['node']) {
      $node_info[$type] = array(
        'name' => $definition['name'],
        'base' => 'quiz_question',
        'description' => $definition['description'],
      );
    }
  }
  return $node_info;
}

/**
 * Figure out if a user has access to score a certain result
 *
 * @param $vid
 *  Question version id
 * @param $result_id
 *  Result id
 * @return
 *  True if the user has access to score the result
 */
function quiz_question_access_to_score($vid, $result_id) {
  global $user;
  $sql = 'SELECT * FROM {quiz_node_results_answers} WHERE result_id = :result_id AND question_vid = :question_vid';
  $answer = db_query($sql, array(
    ':result_id' => $result_id,
    ':question_vid' => $vid,
  ))
    ->fetch();
  if (!$answer) {
    return FALSE;
  }
  if (user_access('score any quiz')) {
    return TRUE;
  }
  if (user_access('score taken quiz answer')) {
    $uid = db_query('SELECT uid from {quiz_node_results} qnr WHERE qnr.result_id = :result_id', array(
      ':result_id' => $result_id,
    ))
      ->fetchField();
    if ($uid == $user->uid) {
      return TRUE;
    }
  }
  if (user_access('score own quiz')) {
    return db_query('SELECT r.uid FROM {node_revision} r
            JOIN {quiz_node_results} qnr ON (r.nid = qnr.nid)
            WHERE qnr.result_id = :result_id
            ', array(
      ':result_id' => $result_id,
    ))
      ->fetchField() == $user->uid;
  }
}

/**
 * Implements hook_form().
 */
function quiz_question_form(&$node, &$form_state) {
  $question = _quiz_question_get_instance($node);
  $form = $question
    ->getNodeForm($form_state);
  return $form;
}

/**
 * Implements hook_validate().
 */
function quiz_question_validate($node, &$form) {

  // Check to make sure that there is a question.
  if (empty($node->body)) {
    form_set_error('body', t('Question text is empty.'));
  }
  _quiz_question_get_instance($node)
    ->validateNode($form);
}

/**
 * Get the form to show to the quiz taker.
 *
 * @param $nodes
 *   A list of question nodes to get answers from.
 * @param $result_id
 *   The result ID for this attempt.
 */
function quiz_question_answering_form($form, $form_state, $nodes, $result_id) {
  $quiz_result = quiz_result_load($result_id);
  $quiz = node_load($quiz_result->nid, $quiz_result->vid);
  if (!is_array($nodes)) {

    // One single question (or page?)
    if ($nodes->type == 'quiz_page') {
      foreach ($quiz_result->layout as $question) {
        if ($question['nid'] == $nodes->nid) {

          // Found a page
          $nodes = array(
            node_load($nodes->nid),
          );
          foreach ($quiz_result->layout as $question2) {
            if ($question2['qnr_pid'] == $question['qnr_id']) {

              // This question belongs in the requested page.
              $nodes[] = node_load($question2['nid']);
            }
          }
          break;
        }
      }
    }
    else {
      $nodes = array(
        $nodes->nid => $nodes,
      );
    }
  }
  $form['#attributes']['class'] = array(
    'answering-form',
  );
  $form['#tree'] = TRUE;
  foreach ($nodes as $node) {
    $question = _quiz_question_get_instance($node);
    $class = drupal_html_class('quiz-question-' . $node->type);

    // Element for a single question
    $element = $question
      ->getAnsweringForm($form_state, $result_id);
    node_build_content($node, 'question');
    unset($node->content['answers']);
    unset($node->content['links']);
    $form['question'][$node->nid] = array(
      '#attributes' => array(
        'class' => array(
          $class,
        ),
      ),
      '#type' => 'container',
      'header' => $node->content,
      'answer' => $element,
    );
    if (!$quiz->allow_change) {
      if (quiz_result_is_question_answered($quiz_result, $node)) {

        // This question was already answered, and not skipped.
        $form['question'][$node->nid]['#disabled'] = TRUE;
      }
    }
    if ($quiz->mark_doubtful) {
      $form['question'][$node->nid]['is_doubtful'] = array(
        '#type' => 'checkbox',
        '#title' => t('Doubtful?'),
      );
      $form['question'][$node->nid]['is_doubtful']['#default_value'] = db_query('SELECT is_doubtful FROM {quiz_node_results_answers} WHERE result_id = :result_id AND question_nid = :question_nid AND question_vid = :question_vid', array(
        ':result_id' => $quiz_result->result_id,
        ':question_nid' => $node->nid,
        ':question_vid' => $node->vid,
      ))
        ->fetchField();
    }
  }
  $is_last = _quiz_show_finish_button($quiz);
  $form['navigation']['#type'] = 'actions';
  $form['navigation']['#theme'] = 'quiz_question_navigation_form';
  if (!empty($quiz->backwards_navigation) && arg(3) != 1) {

    // Backwards navigation enabled, and we are looking at not the first
    // question. @todo detect when on the first page.
    $form['navigation']['back'] = array(
      '#weight' => 10,
      '#type' => 'submit',
      '#value' => t('Back'),
      '#submit' => array(
        'quiz_question_answering_form_submit_back',
      ),
      '#limit_validation_errors' => array(),
    );
    if ($is_last) {
      $form['navigation']['#last'] = TRUE;
      $form['navigation']['last_text'] = array(
        '#weight' => 0,
        '#markup' => '<p><em>' . t('This is the last question. Press Finish to deliver your answers') . '</em></p>',
      );
    }
  }
  $form['navigation']['submit'] = array(
    '#weight' => 30,
    '#type' => 'submit',
    '#value' => $is_last ? t('Finish') : t('Next'),
  );
  if ($is_last && $quiz->backwards_navigation && !$quiz->repeat_until_correct) {

    // Display a confirmation dialogue if this is the last question and a user
    // is able to navigate backwards but not forced to answer correctly.
    $form['#attributes']['class'][] = 'quiz-answer-confirm';
    $form['#attributes']['data-confirm-message'] = t("By proceeding you won't be able to go back and edit your answers.");
    $form['#attached'] = array(
      'js' => array(
        drupal_get_path('module', 'quiz') . '/theme/quiz_confirm.js',
      ),
    );
  }
  if ($quiz->allow_skipping) {
    $form['navigation']['skip'] = array(
      '#weight' => 20,
      '#type' => 'submit',
      '#value' => $is_last ? t('Leave blank and finish') : t('Leave blank'),
      '#access' => $node->type == 'quiz_directions' ? FALSE : TRUE,
      '#submit' => array(
        'quiz_question_answering_form_submit_blank',
      ),
      '#limit_validation_errors' => array(),
    );
  }
  return $form;
}

/**
 * Submit action for "leave blank".
 */
function quiz_question_answering_form_submit_blank($form, &$form_state) {
  $quiz_result = quiz_result_load($_SESSION['quiz'][arg(1)]['result_id']);
  $quiz = node_load($quiz_result->nid, $quiz_result->vid);
  foreach (array_keys($form_state['input']['question']) as $nid) {

    // Loop over all question inputs provided, and record them as skipped.
    $question = node_load($nid);

    // Delete the user's answer.
    _quiz_question_response_get_instance($quiz_result->result_id, $question)
      ->delete();

    // Mark our question attempt as skipped, reset the correct and points flag.
    $qra = quiz_result_answer_load($quiz_result->result_id, $question->nid, $question->vid);
    $qra->is_skipped = 1;
    $qra->is_correct = 0;
    $qra->points_awarded = 0;
    $qra->answer_timestamp = REQUEST_TIME;
    entity_save('quiz_result_answer', $qra);
    quiz_question_goto($quiz, $_SESSION['quiz'][$quiz->nid]['current'] + 1);
  }

  // Advance to next question.
  $form_state['redirect'] = "node/{$quiz->nid}/take/" . $_SESSION['quiz'][$quiz->nid]['current'];
  if (!isset($quiz_result->layout[$_SESSION['quiz'][$quiz->nid]['current']])) {

    // If this is the last question, finalize the quiz.
    quiz_question_answering_form_finalize($form, $form_state);
  }
}

/**
 * Form for teaser display
 *
 * @param $node
 *  The question node
 * @return
 *  Content array
 */
function _quiz_question_teaser_content($node) {
  $content['question_type'] = array(
    '#markup' => '<div class="question_type_name">' . node_type_get_type($node)->name . '</div>',
    '#weight' => -100,
  );
  return $content;
}

/**
 * Update the session for this quiz to the active question.
 *
 * @param type $quiz
 *   A Quiz node.
 * @param type $question_number
 *   Question number starting at 1.
 */
function quiz_question_goto($quiz, $question_number) {
  $_SESSION['quiz'][$quiz->nid]['current'] = $question_number;
}

/**
 * Check if a question has already been answered by anyone.
 *
 * This is to see if a new revision of a question should be made when saving.
 *
 * @return boolean
 *  TRUE if a user has submitted an answer for this question.
 */
function quiz_question_has_been_answered($node) {
  $question_instance = _quiz_question_get_instance($node, true);
  return $question_instance
    ->hasBeenAnswered();
}

/**
 * Implements hook_quiz_question_score().
 */
function quiz_question_quiz_question_score($quiz, $question_nid, $question_vid = NULL, $result_id = NULL) {
  if (!isset($quiz) && !isset($result_id)) {
    return quiz_question_get_max_score($question_nid, $question_vid);
  }

  // We avoid using node_load to increase performance...
  $dummy_node = new stdClass();
  $dummy_node->nid = $question_nid;
  $dummy_node->vid = $question_vid;
  $question = _quiz_question_get_instance($dummy_node, TRUE);
  if (!$question) {
    return FALSE;
  }
  $score = new stdClass();
  $score->possible = $question
    ->getMaximumScore();
  $score->question_nid = $question->node->nid;
  $score->question_vid = $question->node->vid;
  if (isset($result_id)) {
    $response = _quiz_question_response_get_instance($result_id, $question->node);
    $score->attained = $score->possible > 0 ? $response
      ->getScore() : 0;
    $score->possible = $response
      ->getMaxScore();
    $score->is_evaluated = $response
      ->isEvaluated();
  }
  return $score;
}

/**
 * Delete a question response by result and question.
 *
 * @param int $result_id
 *   Result ID
 * @param int $question_nid
 *   Question node ID
 * @param int $question_vid
 *   Question version ID
 */
function quiz_question_delete_result($result_id, $question_nid, $question_vid) {
  $response = _quiz_question_response_get_instance($result_id, NULL, NULL, $question_nid, $question_vid);
  if ($response) {
    $response
      ->delete();
  }
  else {
    drupal_set_message(t('Unable to delete result. A constructor could not be found for the question-type'), 'error');
  }
}

/**
 * Get the configuration form for all enabled question types.
 */
function quiz_question_config($form, $context) {
  $q_types = quiz_question_get_info();
  $form = array();
  $form['#validate'] = array();

  // Go through all question types and merge their config forms
  foreach ($q_types as $type => $values) {
    $function = $type . '_quiz_question_config';
    if ($admin_form = $function()) {
      $form[$type] = $admin_form;
      $form[$type]['#type'] = 'fieldset';
      $form[$type]['#title'] = $values['name'];
      $form[$type]['#collapsible'] = TRUE;
      $form[$type]['#collapsed'] = TRUE;
      if (isset($admin_form['#validate']) && is_array($admin_form['#validate'])) {
        $form['#validate'] = array_merge($form['#validate'], $admin_form['#validate']);
        unset($form[$type]['#validate']);
      }
    }
  }
  return system_settings_form($form);
}

// NODE API

/**
 * Implements hook_node_revision_delete().
 */
function quiz_question_node_revision_delete($node) {
  $q_types = quiz_question_get_info();
  foreach ($q_types as $q_type => $info) {
    if ($node->type == $q_type) {
      _quiz_delete_question($node, TRUE);

      // true for only this version
    }
  }
}

/**
 * Implements hook_node_presave().
 */
function quiz_question_node_presave($node) {
  $q_types = quiz_question_get_info();
  foreach ($q_types as $q_type => $info) {
    if ($node->type == $q_type) {
      if (drupal_strlen($node->title) == 0 || !user_access('edit question titles')) {
        $markup = strip_tags(drupal_render(field_view_field('node', $node, 'body', array(
          'label' => 'hidden',
        ))));
        if (drupal_strlen($markup) > variable_get('quiz_autotitle_length', 50)) {
          $node->title = drupal_substr($markup, 0, variable_get('quiz_autotitle_length', 50) - 3) . '...';
        }
        else {
          $node->title = $markup;
        }
      }
    }
  }
}

/**
 * Implements hook_nodeinsert().
 */
function quiz_question_node_insert(stdClass $node) {
  quiz_question_node_update($node);
}

/**
 * Implements hook_view().
 */

//function quiz_question_view($node, $teaser = FALSE, $page = FALSE) {
function quiz_question_view($node, $view_mode) {
  if ($view_mode == 'search_index' && !variable_get('quiz_index_questions', 1)) {
    $node->body = '';
    $node->content = array();
    $node->title = '';
    $node->taxonomy = array();
    return $node;
  }
  $content = '';
  if ($view_mode == 'teaser') {
    $node->content['question_teaser'] = _quiz_question_teaser_content($node);
  }
  else {

    // normal node view

    //$question = _quiz_question_get_instance($node, TRUE);
    $content = _quiz_question_get_instance($node, TRUE)
      ->getNodeView();
  }

  // put it into the node->content
  if (!empty($content)) {
    $node->content = isset($node->content) ? $node->content + $content : $content;
  }
  return $node;
}

/**
 * Implements hook_node_update().
 */
function quiz_question_node_update($node) {
  if (array_key_exists($node->type, quiz_get_question_types())) {
    _quiz_question_get_instance($node)
      ->save();
  }
}

/**
 * Implements hook_delete().
 */
function quiz_question_delete(&$node) {
  _quiz_delete_question($node, FALSE);
}

/**
 * Delete the question node from the db, and mark its identifiers in the quiz
 * linking table as "NEVER".  This is safer than deleting them
 * and allows for same tracing of what's happened if a question was deleted unintentionally.
 *
 * @param $node the question node
 * @param $only_this_version whether to delete only the specific revision of the question
 */
function _quiz_delete_question($node, $only_this_version) {

  // let each question class delete its own stuff
  _quiz_question_get_instance($node, TRUE)
    ->delete($only_this_version);

  // FIXME QuizQuestion class makes these relationships, so it should handle their 'deletion' too
  // FIXME alternately, move the relationship handling out of QuizQuestion class
  // @todo reconsider this QUESTION_NEVER status, since the node is actually gone
  // then remove it from {quiz_node_relationship} linking table

  //$base_sql = "UPDATE {quiz_node_relationship} SET question_status = " . QUESTION_NEVER;
  $select_sql = 'SELECT parent_vid FROM {quiz_node_relationship}';
  if ($only_this_version) {
    $select_sql .= ' WHERE child_nid = :child_nid AND child_vid = :child_vid';
    $filter_arg = array(
      ':child_nid' => $node->nid,
      ':child_vid' => $node->vid,
    );
  }
  else {
    $select_sql .= ' WHERE child_nid = :child_nid';
    $filter_arg = array(
      ':child_nid' => $node->nid,
    );
  }

  //$res = db_query($select_sql . $filter_sql, $node->nid, $node->vid);
  $res = db_query($select_sql, $filter_arg);

  //db_query($base_sql . $filter_sql, $node->nid, $node->vid);
  $update = db_update('quiz_node_relationship')
    ->fields(array(
    'question_status' => QUIZ_QUESTION_NEVER,
  ))
    ->condition('child_nid', $node->nid);
  if ($only_this_version) {
    $update = $update
      ->condition('child_vid', $node->vid);
  }
  $update
    ->execute();
  $quizzes_to_update = array();
  while ($quizzes_to_update[] = $res
    ->fetchField()) {
  }
  quiz_update_max_score_properties($quizzes_to_update);
}

/**
 * Implements hook_load().
 */
function quiz_question_load($nodes) {
  foreach ($nodes as $nid => &$node) {
    $node_additions = _quiz_question_get_instance($node, TRUE)
      ->getNodeProperties();
    foreach ($node_additions as $property => &$value) {
      $node->{$property} = $value;
    }
  }
}

// END NODE API

/**
 * Get an instance of a quiz question.
 *
 * Get information about the class and use it to construct a new
 * object of the appropriate type.
 *
 * @param $node
 *  Question node
 * @param $use_cached
 *  Can we use a cached version of the node?
 * @return
 *  The appropriate QuizQuestion extension instance
 */
function _quiz_question_get_instance(&$node, $use_cached = FALSE) {

  // We use static caching to improve performance
  static $question_instances = array();
  $using_dummy_node = FALSE;
  if (is_object($node)) {
    $vid = isset($node->vid) ? $node->vid : 0;
    if ($use_cached && isset($question_instances[$vid])) {

      // We just return a cached instance of the QuizQuestion
      return $question_instances[$vid];
    }

    // If $node don't have a type it is a dummy node
    if (!isset($node->type)) {

      // To substanitally improve performance(especially on the result page) we avoid node_load()...
      // @todo why is this? consider getting rid of this as nodes are better
      // cached/retrieved in d7. adding the UID here to get rid of a notice.
      $sql = 'SELECT n.type, r.nid, r.vid, r.title, p.max_score, n.uid
              FROM {node_revision} r
              JOIN {node} n ON r.nid = n.nid
              JOIN {quiz_question_properties} p ON r.vid = p.vid
              WHERE r.vid = :vid';
      $node = db_query($sql, array(
        ':vid' => $node->vid,
      ))
        ->fetch();
      $using_dummy_node = TRUE;
    }
    $name = $node->type;
  }
  elseif (is_array($node)) {
    $name = $node['type'];
    $vid = $node['vid'];
    if ($use_cached && isset($question_instances[$vid])) {

      // We return a cached instance of the appropriate QuizQuestion
      return $question_instances[$vid];
    }
  }

  // No cached instance of QuizQuestion has been returned. We construct a new instance
  $info = quiz_question_get_info();
  $constructor = $info[$name]['question provider'];
  if (empty($constructor)) {
    return FALSE;
  }

  // We create a new instance of QuizQuestion
  $to_return = new $constructor($node);
  if (!$to_return instanceof QuizQuestion) {

    // Make sure the constructor is creating an extension of QuizQuestion
    drupal_set_message(t('The question-type %name isn\'t a QuizQuestion. It needs to extend the QuizQuestion class.', array(
      '%name' => $name,
    )), 'error', FALSE);
  }

  // If we're using a dummy node we have to run getNodeProperties, and populate the node with those properties
  if ($using_dummy_node) {
    $props = $to_return
      ->getNodeProperties();
    foreach ($props as $key => $value) {
      $to_return->node->{$key} = $value;
    }
  }

  // Cache the node
  $question_instances[$vid] = $to_return;
  return $to_return;
}

/**
 * Get an instance of a quiz question responce.
 *
 * Get information about the class and use it to construct a new
 * object of the appropriate type.
 *
 * @param $result_id
 *  Result id
 * @param $question
 *  The question node(not a QuizQuestion instance)
 * @param $answer
 *  Resonce to the answering form.
 * @param $nid
 *  Question node id
 * @param $vid
 *  Question node version id
 * @return
 *  The appropriate QuizQuestionResponce extension instance
 */
function _quiz_question_response_get_instance($result_id, $question, $answer = NULL, $nid = NULL, $vid = NULL) {

  // We cache responses to improve performance
  static $quiz_responses = array();
  if (is_object($question) && isset($quiz_responses[$result_id][$question->vid])) {

    // We refresh the question node in case it has been changed since we cached the response
    $quiz_responses[$result_id][$question->vid]
      ->refreshQuestionNode($question);
    if ($quiz_responses[$result_id][$question->vid]->is_skipped !== FALSE) {
      return $quiz_responses[$result_id][$question->vid];
    }
  }
  elseif (isset($quiz_responses[$result_id][$vid])) {
    if ($quiz_responses[$result_id][$vid]->is_skipped !== FALSE) {
      return $quiz_responses[$result_id][$vid];
    }
  }
  if (!isset($quiz_responses[$result_id])) {

    // Prepare to cache responses for this result id
    $quiz_responses[$result_id] = array();
  }

  // If the question node isn't set we fetch it from the QuizQuestion instance this responce belongs to
  if (!isset($question)) {
    $question_node = node_load($nid, $vid);
    $question = _quiz_question_get_instance($question_node, TRUE)->node;
  }
  if (!$question) {
    return FALSE;
  }
  $info = quiz_question_get_info();
  $constructor = $info[$question->type]['response provider'];
  $to_return = new $constructor($result_id, $question, $answer);

  // All responce classes must extend QuizQuestionResponse
  if (!$to_return instanceof QuizQuestionResponse) {
    drupal_set_message(t('The question-response isn\'t a QuizQuestionResponse. It needs to extend the QuizQuestionResponse interface, or extend the abstractQuizQuestionResponse class.'), 'error', FALSE);
  }
  $result = $to_return
    ->getReport();
  $to_return->question->answers[$result['answer_id']] = $result;
  $to_return->question->correct = $result['is_correct'];

  // Cache the responce instance
  $quiz_responses[$result_id][$question->vid] = $to_return;
  return $to_return;
}

/**
 * Get the information about various implementations of quiz questions.
 *
 * @param string $name
 *  The question type, e.g. truefalse, for which the info shall be returned, or
 *  NULL to return an array with info about all types.
 * @param bool $reset
 *  If this is true, the cache will be reset.
 * @return
 *  An array of information about quiz question implementations.
 * @see quiz_question_quiz_question_info() for an example of a quiz question info hook.
 */
function quiz_question_get_info($name = NULL, $reset = FALSE) {
  $info =& drupal_static(__FUNCTION__, array());
  if (empty($info) || $reset) {
    $qtypes = module_invoke_all('quiz_question_info');
    foreach ($qtypes as $type => $definition) {

      // We only want the ones with classes.
      if (!empty($definition['question provider'])) {

        // Cache the info
        $info[$type] = $definition;
      }
    }
    drupal_alter('quiz_question_info', $info);
  }
  return NULL === $name ? $info : $info[$info];
}

/**
 * Get the max score for a question
 *
 * @param $nid
 *  Question node id
 * @param $vid
 *  Question node version id
 * @return
 *  Max score(int)
 */
function quiz_question_get_max_score($nid, $vid) {
  return db_query('SELECT max_score
          FROM {quiz_question_properties}
          WHERE nid = :nid AND vid = :vid', array(
    ':nid' => $nid,
    ':vid' => $vid,
  ))
    ->fetchField();
}

/**
 * Returns a result report for a question response.
 *
 * The retaurned value is a form array because in some contexts the scores in the form
 * is editable
 *
 * @param $question
 *  The question node
 * @return
 *  FAPI form array
 */
function quiz_question_report_form($question, $result_id) {
  $response_instance = _quiz_question_response_get_instance($result_id, $question);
  $answer = $response_instance->question->answers[0];

  // If need to specify the score weight if it isn't already specified.
  if (!isset($response_instance->question->score_weight)) {
    $vid = db_query('SELECT vid FROM {quiz_node_results}
      WHERE result_id = :rid', array(
      ':rid' => $answer['result_id'],
    ))
      ->fetchField();
    $qnr_max_score = db_query('SELECT qnr.max_score FROM {quiz_node_relationship} qnr
      WHERE qnr.child_vid = :child_vid AND qnr.parent_vid = :parent_vid', array(
      ':child_vid' => $question->vid,
      ':parent_vid' => $vid,
    ))
      ->fetchField();
    if ($qnr_max_score === FALSE) {
      $qnr_max_score = db_query('SELECT qt.max_score FROM {quiz_node_results} qnr
         JOIN {quiz_node_results_answers} qnra ON (qnr.result_id = qnra.result_id)
         JOIN {quiz_terms} qt ON (qt.vid = qnr.vid AND qt.tid = qnra.tid)
         WHERE qnr.result_id = :rid AND qnra.question_nid = :qnid AND qnra.question_vid = :qvid', array(
        ':rid' => $answer['result_id'],
        ':qnid' => $question->nid,
        ':qvid' => $question->vid,
      ))
        ->fetchField();
    }
    $response_instance->question->score_weight = $qnr_max_score == 0 || $response_instance->question->max_score == 0 ? 0 : $qnr_max_score / $response_instance->question->max_score;
  }
  return $response_instance
    ->getReportForm();
}

/**
 * Add body field to quiz_question nodes.
 */
function quiz_question_add_body_field($type) {
  node_types_rebuild();
  $node_type = node_type_get_type($type);
  if (!$node_type) {
    watchdog('quiz', 'Attempt to add body field was failed as question content type %type is not defined.', array(
      '%type' => $type,
    ), WATCHDOG_ERROR);
    watchdog('quiz', '<pre>' . print_r(node_type_get_types(), 1), array(), WATCHDOG_ERROR);
    return;
  }
  node_add_body_field($node_type, 'Question');

  // Override default weight to make body field appear first
  $instance = field_read_instance('node', 'body', $type);
  $instance['widget']['weight'] = -10;
  $instance['widget']['settings']['rows'] = 6;

  // Make the question body visible by default for the question view mode
  $instance['display']['question'] = array(
    'label' => 'hidden',
    'type' => 'text_default',
    'weight' => 1,
    'settings' => array(),
    'module' => 'text',
  );
  field_update_instance($instance);
}

/**
 * Return a form with question feedback.
 */
function quiz_question_feedback($quiz, $question) {
  if (empty($_SESSION['quiz'][$quiz->nid]['result_id'])) {
    $result_id = $_SESSION['quiz']['temp']['result_id'];
  }
  else {
    $result_id = $_SESSION['quiz'][$quiz->nid]['result_id'];
  }
  module_load_include('inc', 'quiz', 'quiz.pages');
  if ($question) {
    $report_form = drupal_get_form('quiz_report_form', array(
      $question,
    ), $result_id);
    return $report_form;
  }
}

/**
 * Submit handler for the question answering form.
 *
 * There is no validation code here, but there may be feedback code for
 * correct feedback.
 */
function quiz_question_answering_form_submit(&$form, &$form_state) {
  $feedback_count = 0;
  $quiz_result = quiz_result_load($_SESSION['quiz'][arg(1)]['result_id']);
  $quiz = node_load($quiz_result->nid, $quiz_result->vid);
  $time_reached = $quiz->time_limit && REQUEST_TIME > $quiz_result->time_start + $quiz->time_limit;
  if ($time_reached) {

    // Too late.
    // @todo move to quiz_question_answering_form_validate(), and then put all
    // the "quiz end" logic in a sharable place. We just need to not fire the
    // logic that saves all the users answers.
    drupal_set_message(t('The last answer was not submitted, as the time ran out.'), 'error');
  }
  else {
    $questions = $quiz_result->layout;
    if (!empty($form_state['values']['question'])) {
      foreach ($form_state['values']['question'] as $nid => $response) {
        $answer = $response['answer'];
        foreach ($questions as $question) {
          if ($question['nid'] == $nid) {
            $question_array = $question;
            $current_question = node_load($question['nid'], $question['vid']);
          }
        }
        $qi_instance = _quiz_question_response_get_instance($_SESSION['quiz'][$quiz->nid]['result_id'], $current_question, $form_state['values']['question'][$current_question->nid]['answer']);
        $qi_instance
          ->delete();
        $qi_instance
          ->save();
        $result = $qi_instance
          ->toBareObject();
        $result->is_doubtful = !empty($response['is_doubtful']);
        quiz_store_question_result($quiz, $result, array(
          'set_msg' => TRUE,
          'question_data' => $question_array,
        ));

        // Increment the counter.
        quiz_question_goto($quiz, $_SESSION['quiz'][$quiz->nid]['current'] + 1);
        $feedback_count += $qi_instance->quizQuestion
          ->hasFeedback();
      }
    }
  }

  // Wat do?
  if (!empty($quiz->review_options['question']) && array_filter($quiz->review_options['question']) && $feedback_count) {

    // We have question feedback.
    $form_state['redirect'] = "node/{$quiz->nid}/take/" . ($_SESSION['quiz'][$quiz->nid]['current'] - 1) . '/feedback';
    $form_state['feedback'] = TRUE;
  }
  else {

    // No question feedback. Go to next question.
    $form_state['redirect'] = "node/{$quiz->nid}/take/" . $_SESSION['quiz'][$quiz->nid]['current'];
  }
  if ($time_reached || !isset($quiz_result->layout[$_SESSION['quiz'][$quiz->nid]['current']])) {

    // If this is the last question, finalize the quiz.
    quiz_question_answering_form_finalize($form, $form_state);
  }
}

/**
 * Helper function to finalize a quiz attempt.
 * @see quiz_question_answering_form_submit()
 * @see quiz_question_answering_form_submit_blank()
 */
function quiz_question_answering_form_finalize(&$form, &$form_state) {
  $quiz_result = quiz_result_load($_SESSION['quiz'][arg(1)]['result_id']);
  $quiz = node_load($quiz_result->nid, $quiz_result->vid);

  // No more questions. Score quiz.
  $score = quiz_end_scoring($_SESSION['quiz'][$quiz->nid]['result_id']);
  if (empty($quiz->review_options['question']) || !array_filter($quiz->review_options['question']) || empty($form_state['feedback'])) {

    // Only redirect to question results if there is not question feedback.
    $form_state['redirect'] = "node/{$quiz->nid}/quiz-results/{$quiz_result->result_id}/view";
  }
  quiz_end_actions($quiz, $score, $_SESSION['quiz'][$quiz->nid]);

  // Remove all information about this quiz from the session.
  // @todo but for anon, we might have to keep some so they could access
  // results
  // When quiz is completed we need to make sure that even though the quiz has
  // been removed from the session, that the user can still access the
  // feedback for the last question, THEN go to the results page.
  $_SESSION['quiz']['temp']['result_id'] = $quiz_result->result_id;
  unset($_SESSION['quiz'][$quiz->nid]);
}

/**
 * Implements hook_quiz_result_update().
 */
function quiz_quiz_result_update($quiz_result) {
  if (!$quiz_result->original->is_evaluated && $quiz_result->is_evaluated) {

    // Quiz is finished!
    $quiz = node_load($quiz_result->nid);

    // Delete old results if necessary.
    _quiz_maintain_results($quiz, $quiz_result->result_id);
  }
}

/**
 * Submit handler for "back".
 */
function quiz_question_answering_form_submit_back(&$form, &$form_state) {

  // Back a question.
  $quiz = node_load(arg(1));
  quiz_question_goto($quiz, $_SESSION['quiz'][$quiz->nid]['current'] - 1);
  $quiz_result = quiz_result_load($_SESSION['quiz'][$quiz->nid]['result_id']);
  $question = $quiz_result->layout[$_SESSION['quiz'][$quiz->nid]['current']];
  if (!empty($question['qnr_pid'])) {
    foreach ($quiz_result->layout as $question2) {
      if ($question2['qnr_id'] == $question['qnr_pid']) {
        quiz_question_goto($quiz, $question2['number']);
      }
    }
  }
  $form_state['redirect'] = "node/{$quiz->nid}/take/" . $_SESSION['quiz'][$quiz->nid]['current'];
}

/**
 * Validation callback for quiz question submit.
 */
function quiz_question_answering_form_validate(&$form, &$form_state) {
  $quiz = node_load(arg(1));
  $quiz_result = quiz_result_load($_SESSION['quiz'][arg(1)]['result_id']);
  $time_reached = $quiz->time_limit && REQUEST_TIME > $quiz_result->time_start + $quiz->time_limit;
  if ($time_reached) {

    // Let's not validate anything, because the input won't get saved in submit
    // either.
    return;
  }
  foreach (array_keys($form_state['values']['question']) as $nid) {
    $current_question = node_load($nid);
    if ($current_question) {

      // There was an answer submitted.
      $quiz_question = _quiz_question_get_instance($current_question);
      $quiz_question
        ->getAnsweringFormValidate($form, $form_state);
    }
  }
}

/**
 * Implements hook_node_access_records().
 */
function quiz_question_node_access_records($node) {
  $grants = array();

  // Restricting view access to question nodes outside quizzes.
  $question_types = quiz_question_get_info();
  $question_types = array_keys($question_types);
  if (in_array($node->type, $question_types)) {

    // This grant is for users having 'view quiz question outside of a quiz'
    // permission. We set a priority of 2 because OG has a 1 priority and we
    // want to get around it.
    $grants[] = array(
      'realm' => 'quiz_question',
      'gid' => 1,
      'grant_view' => 1,
      'grant_update' => 0,
      'grant_delete' => 0,
      'priority' => 2,
    );
  }
  return $grants;
}

/**
 * Implements hook_node_grants().
 */
function quiz_question_node_grants($account, $op) {
  $grants = array();
  if ($op == 'view') {
    if (user_access('view quiz question outside of a quiz')) {

      // Granting view access
      $grants['quiz_question'][] = 1;
    }
  }
  return $grants;
}

/**
 * Element validator (for repeat until correct).
 */
function quiz_question_element_validate(&$element, &$form_state) {
  $quiz = node_load(arg(1));
  $question_nid = $element['#array_parents'][1];
  $answer = $form_state['values']['question'][$question_nid]['answer'];
  $current_question = node_load($question_nid);

  // There was an answer submitted.
  $result = _quiz_question_response_get_instance($_SESSION['quiz'][$quiz->nid]['result_id'], $current_question, $answer);
  if ($quiz->repeat_until_correct && !$result
    ->isCorrect()) {
    form_set_error('', t('The answer was incorrect. Please try again.'));
    $feedback = quiz_question_feedback($quiz, $current_question);
    $element['feedback'] = array(
      '#weight' => 100,
      '#markup' => drupal_render($feedback),
    );
  }
}

/**
 * Theme the feedback for any question type.
 */
function theme_quiz_question_feedback($variables) {
  $rows = $variables['data'];
  $headers = array_intersect_key($variables['labels'], $rows[0]);
  return theme('table', array(
    'header' => $headers,
    'rows' => $rows,
  ));
}

/**
 * Helper function to faciliate icon display, like "correct" or "selected".
 */
function quiz_icon($icon) {
  return theme('quiz_answer_result', array(
    'type' => $icon,
  ));
}

/**
 * Implements hook_entity_info().
 */
function quiz_question_entity_info() {
  return array(
    'quiz_question' => array(
      'base table' => 'quiz_question_properties',
      'controller class' => 'QuizQuestionController',
      'entity class' => 'Entity',
      'entity keys' => array(
        'id' => 'qqp_id',
      ),
      'label' => 'Quiz question properties',
      'metadata controller class' => 'QuizQuestionMetadataController',
      'views controller class' => 'EntityDefaultViewsController',
    ),
  );
}

Functions

Name	Description
quiz_icon	Helper function to faciliate icon display, like "correct" or "selected".
quiz_question_access_to_score	Figure out if a user has access to score a certain result
quiz_question_add_body_field	Add body field to quiz_question nodes.
quiz_question_answering_form	Get the form to show to the quiz taker.
quiz_question_answering_form_finalize	Helper function to finalize a quiz attempt.
quiz_question_answering_form_submit	Submit handler for the question answering form.
quiz_question_answering_form_submit_back	Submit handler for "back".
quiz_question_answering_form_submit_blank	Submit action for "leave blank".
quiz_question_answering_form_validate	Validation callback for quiz question submit.
quiz_question_config	Get the configuration form for all enabled question types.
quiz_question_delete	Implements hook_delete().
quiz_question_delete_result	Delete a question response by result and question.
quiz_question_element_validate	Element validator (for repeat until correct).
quiz_question_entity_info	Implements hook_entity_info().
quiz_question_feedback	Return a form with question feedback.
quiz_question_form	Implements hook_form().
quiz_question_get_info	Get the information about various implementations of quiz questions.
quiz_question_get_max_score	Get the max score for a question
quiz_question_goto	Update the session for this quiz to the active question.
quiz_question_has_been_answered	Check if a question has already been answered by anyone.
quiz_question_help	Implements hook_help().
quiz_question_load	Implements hook_load().
quiz_question_menu	Implements hook_menu().
quiz_question_node_access_records	Implements hook_node_access_records().
quiz_question_node_grants	Implements hook_node_grants().
quiz_question_node_info	Implements hook_node_info().
quiz_question_node_insert	Implements hook_nodeinsert().
quiz_question_node_presave	Implements hook_node_presave().
quiz_question_node_revision_delete	Implements hook_node_revision_delete().
quiz_question_node_update	Implements hook_node_update().
quiz_question_quiz_question_score	Implements hook_quiz_question_score().
quiz_question_report_form	Returns a result report for a question response.
quiz_question_theme	Implements hook_theme().
quiz_question_validate	Implements hook_validate().
quiz_question_view
quiz_quiz_result_update	Implements hook_quiz_result_update().
theme_quiz_question_feedback	Theme the feedback for any question type.
_quiz_delete_question	Delete the question node from the db, and mark its identifiers in the quiz linking table as "NEVER". This is safer than deleting them and allows for same tracing of what's happened if a question was deleted unintentionally.
_quiz_question_get_instance	Get an instance of a quiz question.
_quiz_question_response_get_instance	Get an instance of a quiz question responce.
_quiz_question_teaser_content	Form for teaser display