/question/format/learnwise/format.php

<?php    // $Id: format.php,v 1.4.4.1 2007/11/02 16:21:06 tjhunt Exp $ 

// Alton College, Hampshire, UK - Tom Flannaghan, Andrew Walker

// Imports learnwise multiple choice quizzes (single and multiple answers)

// currently ignores the deduct attribute for multiple answer questions

// deductions are currently simply found by dividing the award for the incorrect 

// answer by the total number of options

// Based on format.php, included by ../../import.php

/**

 * @package questionbank

 * @subpackage importexport

 */



class qformat_learnwise extends qformat_default {



    function provide_import() {

      return true;

    }



    function readquestions($lines) {

        $questions = array();

        $currentquestion = array();



        foreach($lines as $line) {

            $line = trim($line);

            $currentquestion[] = $line;



            if ($question = $this->readquestion($currentquestion)) {

                $questions[] = $question;

                $currentquestion = array();

            }

        }

        return $questions;

    }



    function readquestion($lines) {

        $text = implode(' ', $lines);

        $text = str_replace(array('\t','\n','\r','\''), array('','','','\\\''), $text);



        $startpos = strpos($text, '<question type');

        $endpos = strpos($text, '</question>');

        if ($startpos === false || $endpos === false) {

            return false;

        }



        preg_match("/<question type=[\"\']([^\"\']+)[\"\']>/i", $text, $matches);

        $type = strtolower($matches[1]); // multichoice or multianswerchoice



        $questiontext = $this->unhtmlentities($this->stringbetween($text, '<text>', '</text>'));

        $questionhint = $this->unhtmlentities($this->stringbetween($text, '<hint>', '</hint>'));

        $questionaward = $this->stringbetween($text, '<award>', '</award>');

        $optionlist = $this->stringbetween($text, '<answer>', '</answer>');



        $optionlist = explode('<option', $optionlist);



        $n = 0;



        $optionscorrect = array();

        $optionstext = array();



        if ($type == 'multichoice') {

            foreach ($optionlist as $option) {

                $correct = $this->stringbetween($option, ' correct="', '">');

                $answer = $this->stringbetween($option, '">', '</option>');

                $optionscorrect[$n] = $correct; 

                $optionstext[$n] = $this->unhtmlentities($answer);

                ++$n;

            }

        } else if ($type == 'multianswerchoice') {

            $numcorrect = 0;

            $totalaward = 0;



            $optionsaward = array();



            foreach ($optionlist as $option) {

                preg_match("/correct=\"([^\"]*)\"/i", $option, $correctmatch);

                preg_match("/award=\"([^\"]*)\"/i", $option, $awardmatch);



                $correct = $correctmatch[1];

                $award = $awardmatch[1];

                if ($correct == 'yes') {

                    $totalaward += $award;

                    ++$numcorrect;

                }



                $answer = $this->stringbetween($option, '">', '</option>');



                $optionscorrect[$n] = $correct; 

                $optionstext[$n] = $this->unhtmlentities($answer);

                $optionsaward[$n] = $award;

                ++$n;

            }



        } else {

            echo "<p>I don't understand this question type (type = <strong>$type</strong>).</p>\n";

        }



        $question = $this->defaultquestion();

        $question->qtype = MULTICHOICE;

        $question->name = substr($questiontext, 0, 30);

        if (strlen($questiontext) > 30) {

            $question->name .= '...';

        }



        $question->questiontext = $questiontext;

        $question->single = ($type == 'multichoice') ? 1 : 0;

        $question->feedback[] = '';



        $question->fraction = array();

        $question->answer = array();

        for ($n = 0; $n < count($optionstext); ++$n) {

            if ($optionstext[$n]) {

                if (!isset($numcorrect)) { // single answer

                    if ($optionscorrect[$n] == 'yes') {

                        $fraction = (int) $questionaward; 

                    } else {

                        $fraction = 0;

                    } 

                } else { // mulitple answers

                    if ($optionscorrect[$n] == 'yes') {

                        $fraction = $optionsaward[$n] / $totalaward; 

                    } else {

                        $fraction = -$optionsaward[$n] / count($optionstext);

                    }

                }

                $question->fraction[] = $fraction;

                $question->answer[] = $optionstext[$n];

                $question->feedback[] = ''; // no feedback in this type

            }

        }



        return $question;

    }



    function stringbetween($text, $start, $end) {

        $startpos = strpos($text, $start) + strlen($start);

        $endpos = strpos($text, $end);



        if ($startpos <= $endpos) {

            return substr($text, $startpos, $endpos - $startpos);

        }

    }



    function unhtmlentities($string) {

        $transtable = get_html_translation_table(HTML_ENTITIES);

        $transtable = array_flip($transtable);

        return strtr($string, $transtable);

    } 



}



?>