class.ilTestRandomQuestionSetQuestionCollection.php

Go to the documentation of this file.

<?php
/* Copyright (c) 1998-2013 ILIAS open source, Extended GPL, see docs/LICENSE */

require_once 'Modules/Test/classes/class.ilTestRandomQuestionSetQuestion.php';

class ilTestRandomQuestionSetQuestionCollection
{
        private $questions = array();

        public function setQuestions($questions)
        {
                $this->questions = $questions;
        }

        public function getQuestions()
        {
                return $this->questions;
        }

        public function addQuestion(ilTestRandomQuestionSetQuestion $question)
        {
                $this->questions[] = $question;
        }

        public function isGreaterThan($amount)
        {
                return count($this->questions) > $amount;
        }

        public function isSmallerThan($amount)
        {
                return count($this->questions) < $amount;
        }

        public function getMissingCount($amount)
        {
                return $amount - count($this->questions);
        }

        public function shuffleQuestions()
        {
                shuffle($this->questions);
        }

        public function mergeQuestionCollection(self $questionCollection)
        {
                $this->questions = array_merge( $this->questions, $questionCollection->getQuestions() );
        }

        public function getUniqueQuestionCollection()
        {
                $uniqueQuestions = array();

                foreach($this->getQuestions() as $question)
                {
                        /* @var ilTestRandomQuestionSetQuestion $question */

                        if( !isset($uniqueQuestions[$question->getQuestionId()]) )
                        {
                                $uniqueQuestions[$question->getQuestionId()] = $question;
                        }
                }

                $uniqueQuestionCollection = new self();
                $uniqueQuestionCollection->setQuestions($uniqueQuestions);

                return $uniqueQuestionCollection;
        }

        public function getRelativeComplementCollection(self $questionCollection)
        {
                $questionIds = array_flip( $questionCollection->getInvolvedQuestionIds() );

                $relativeComplementCollection = new self();

                foreach($this->getQuestions() as $question)
                {
                        if( !isset($questionIds[$question->getQuestionId()]) )
                        {
                                $relativeComplementCollection->addQuestion($question);
                        }
                }

                return $relativeComplementCollection;
        }

        public function getInvolvedQuestionIds()
        {
                $questionIds = array();

                foreach($this->getQuestions() as $question)
                {
                        $questionIds[] = $question->getQuestionId();
                }

                return $questionIds;
        }

        public function getRandomQuestionCollection($requiredAmount)
        {
                $randomKeys = $this->getRandomArrayKeys($this->questions, $requiredAmount);

                $randomQuestionCollection = new self();

                foreach($randomKeys as $randomKey)
                {
                        $randomQuestionCollection->addQuestion( $this->questions[$randomKey] );
                }

                return $randomQuestionCollection;
        }

        private function getRandomArrayKeys($array, $numKeys)
        {
                if( $numKeys < 1 )
                {
                        return array();
                }

                if( $numKeys > 1 )
                {
                        return array_rand($array, $numKeys);
                }

                return array( array_rand($array, $numKeys) );
        }
}