<?php
 /*
   +----------------------------------------------------------------------------+
   | ILIAS open source                                                          |
   +----------------------------------------------------------------------------+
   | Copyright (c) 1998-2001 ILIAS open source, University of Cologne           |
   |                                                                            |
   | This program is free software; you can redistribute it and/or              |
   | modify it under the terms of the GNU General Public License                |
   | as published by the Free Software Foundation; either version 2             |
   | of the License, or (at your option) any later version.                     |
   |                                                                            |
   | This program is distributed in the hope that it will be useful,            |
   | but WITHOUT ANY WARRANTY; without even the implied warranty of             |
   | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              |
   | GNU General Public License for more details.                               |
   |                                                                            |
   | You should have received a copy of the GNU General Public License          |
   | along with this program; if not, write to the Free Software                |
   | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
   +----------------------------------------------------------------------------+
*/
include_once "./Modules/TestQuestionPool/classes/class.assQuestion.php";
include_once "./Modules/Test/classes/inc.AssessmentConstants.php";

/**
* Class for multiple choice tests
*
* assMultipleChoice is a class for multiple choice questions
*
* @author		Helmut Schottmüller <helmut.schottmueller@mac.com>
* @version	$Id: class.assMultipleChoice.php 19622 2009-04-14 11:53:21Z hschottm $
* @ingroup ModulesTestQuestionPool
*/
class assMultipleChoice extends assQuestion
{
	/**
	* The given answers of the multiple choice question
	*
	* $answers is an array of the given answers of the multiple choice question
	*
	* @var array
	*/
	var $answers;

	/**
	* Output type
	*
	* This is the output type for the answers of the multiple choice question. You can select
	* OUTPUT_ORDER(=0) or OUTPUT_RANDOM (=1). The default output type is OUTPUT_ORDER
	*
	* @var integer
	*/
	var $output_type;

	/**
	* assMultipleChoice constructor
	*
	* The constructor takes possible arguments an creates an instance of the assMultipleChoice object.
	*
	* @param string $title A title string to describe the question
	* @param string $comment A comment string to describe the question
	* @param string $author A string containing the name of the questions author
	* @param integer $owner A numerical ID to identify the owner/creator
	* @param string $question The question string of the multiple choice question
	* @param integer $output_type The output order of the multiple choice answers
	* @access public
	* @see assQuestion:assQuestion()
	*/
	function assMultipleChoice(
		$title = "",
		$comment = "",
		$author = "",
		$owner = -1,
		$question = "",
		$output_type = OUTPUT_ORDER
	  )
	{
		$this->assQuestion($title, $comment, $author, $owner, $question);
		$this->output_type = $output_type;
		$this->answers = array();
	}

	/**
	* Returns true, if a multiple choice question is complete for use
	*
	* Returns true, if a multiple choice question is complete for use
	*
	* @return boolean True, if the multiple choice question is complete for use, otherwise false
	* @access public
	*/
	function isComplete()
	{
		if (($this->title) and ($this->author) and ($this->question) and (count($this->answers)) and ($this->getMaximumPoints() > 0))
		{
			return true;
		}
			else
		{
			return false;
		}
	}

	/**
	* Saves a assMultipleChoice object to a database
	*
	* Saves a assMultipleChoice object to a database (experimental)
	*
	* @param object $db A pear DB object
	* @access public
	*/
	function saveToDb($original_id = "")
	{
		global $ilDB;

		$complete = 0;
		if ($this->isComplete())
		{
			$complete = 1;
		}

		$estw_time = $this->getEstimatedWorkingTime();
		$estw_time = sprintf("%02d:%02d:%02d", $estw_time['h'], $estw_time['m'], $estw_time['s']);

		if ($original_id)
		{
			$original_id = $ilDB->quote($original_id);
		}
		else
		{
			$original_id = "NULL";
		}
		
		include_once("./Services/RTE/classes/class.ilRTE.php");

		if ($this->id == -1)
		{
			// Neuen Datensatz schreiben
			$now = getdate();
			$question_type = $this->getQuestionTypeID();
			$created = sprintf("%04d%02d%02d%02d%02d%02d", $now['year'], $now['mon'], $now['mday'], $now['hours'], $now['minutes'], $now['seconds']);
			$query = sprintf("INSERT INTO qpl_questions (question_id, question_type_fi, obj_fi, title, comment, author, owner, question_text, points, working_time, complete, created, original_id, TIMESTAMP) VALUES (NULL, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, NULL)",
				$ilDB->quote($question_type),
				$ilDB->quote($this->obj_id),
				$ilDB->quote($this->title),
				$ilDB->quote($this->comment),
				$ilDB->quote($this->author),
				$ilDB->quote($this->owner),
				$ilDB->quote(ilRTE::_replaceMediaObjectImageSrc($this->question, 0)),
				$ilDB->quote($this->getMaximumPoints() . ""),
				$ilDB->quote($estw_time),
				$ilDB->quote("$complete"),
				$ilDB->quote($created),
				$original_id
			);
			$result = $ilDB->query($query);
			
			if (PEAR::isError($result)) 
			{
				global $ilias;
				$ilias->raiseError($result->getMessage());
			}
			else
			{
				$this->id = $ilDB->getLastInsertId();
				$query = sprintf("INSERT INTO qpl_question_multiplechoice (question_fi, shuffle) VALUES (%s, %s)",
					$ilDB->quote($this->id . ""),
					$ilDB->quote("$this->shuffle")
				);
				$ilDB->query($query);

				// create page object of question
				$this->createPageObject();

				// Falls die Frage in einen Test eingefügt werden soll, auch diese Verbindung erstellen
				if ($this->getTestId() > 0)
				{
				$this->insertIntoTest($this->getTestId());
				}
			}
		}
		else
		{
			// Vorhandenen Datensatz aktualisieren
			$query = sprintf("UPDATE qpl_questions SET obj_fi = %s, title = %s, comment = %s, author = %s, question_text = %s, points = %s, working_time=%s, complete = %s WHERE question_id = %s",
				$ilDB->quote($this->obj_id. ""),
				$ilDB->quote($this->title),
				$ilDB->quote($this->comment),
				$ilDB->quote($this->author),
				$ilDB->quote(ilRTE::_replaceMediaObjectImageSrc($this->question, 0)),
				$ilDB->quote($this->getMaximumPoints() . ""),
				$ilDB->quote($estw_time),
				$ilDB->quote("$complete"),
				$ilDB->quote($this->id)
			);
			$result = $ilDB->query($query);
			$query = sprintf("UPDATE qpl_question_multiplechoice SET shuffle = %s WHERE question_fi = %s",
				$ilDB->quote("$this->shuffle"),
				$ilDB->quote($this->id . "")
			);
			$result = $ilDB->query($query);
		}
		
		if (PEAR::isError($result)) 
		{
			global $ilias;
			$ilias->raiseError($result->getMessage());
		}
		else
		{
			// Antworten schreiben
			// alte Antworten löschen
			$query = sprintf("DELETE FROM qpl_answer_multiplechoice WHERE question_fi = %s",
				$ilDB->quote($this->id)
			);
			$result = $ilDB->query($query);

			// Anworten wegschreiben
			foreach ($this->answers as $key => $value)
			{
				$answer_obj = $this->answers[$key];

				$query = sprintf("INSERT INTO qpl_answer_multiplechoice (answer_id, question_fi, answertext, points, points_unchecked, aorder, imagefile) VALUES (NULL, %s, %s, %s, %s, %s, %s)",
					$ilDB->quote($this->id),
					$ilDB->quote(ilRTE::_replaceMediaObjectImageSrc($answer_obj->getAnswertext(), 0)),
					$ilDB->quote($answer_obj->getPoints() . ""),
					$ilDB->quote($answer_obj->getPointsUnchecked() . ""),
					$ilDB->quote($answer_obj->getOrder() . ""),
					$ilDB->quote($answer_obj->getImage() . "")
				);
				$answer_result = $ilDB->query($query);
			}
		}

		parent::saveToDb($original_id);
	}

	/**
	* Loads a assMultipleChoice object from a database
	*
	* Loads a assMultipleChoice object from a database (experimental)
	*
	* @param object $db A pear DB object
	* @param integer $question_id A unique key which defines the multiple choice test in the database
	* @access public
	*/
	function loadFromDb($question_id)
	{
		global $ilDB;

		$hasimages = 0;
    $query = sprintf("SELECT qpl_questions.*, qpl_question_multiplechoice.* FROM qpl_questions, qpl_question_multiplechoice WHERE question_id = %s AND qpl_questions.question_id = qpl_question_multiplechoice.question_fi",
		$ilDB->quote($question_id));
		$result = $ilDB->query($query);
		if ($result->numRows() == 1)
		{
			$data = $result->fetchRow(MDB2_FETCHMODE_OBJECT);
			$this->id = $question_id;
			$this->title = $data->title;
			$this->comment = $data->comment;
			$this->solution_hint = $data->solution_hint;
			$this->original_id = $data->original_id;
			$this->obj_id = $data->obj_fi;
			$this->author = $data->author;
			$this->owner = $data->owner;
			$this->points = $data->points;
			include_once("./Services/RTE/classes/class.ilRTE.php");
			$this->question = ilRTE::_replaceMediaObjectImageSrc($data->question_text, 1);
			$this->setShuffle($data->shuffle);
			$this->setEstimatedWorkingTime(substr($data->working_time, 0, 2), substr($data->working_time, 3, 2), substr($data->working_time, 6, 2));

			$query = sprintf("SELECT * FROM qpl_answer_multiplechoice WHERE question_fi = %s ORDER BY aorder ASC",
				$ilDB->quote($question_id));

			$result = $ilDB->query($query);

			include_once "./Modules/TestQuestionPool/classes/class.assAnswerMultipleResponseImage.php";
			if ($result->numRows() > 0)
			{
				while ($data = $result->fetchRow(MDB2_FETCHMODE_OBJECT))
				{
					$imagefilename = $this->getImagePath() . $data->imagefile;
					if (!@file_exists($imagefilename))
					{
						$data->imagefile = "";
					}
					include_once("./Services/RTE/classes/class.ilRTE.php");
					$data->answertext = ilRTE::_replaceMediaObjectImageSrc($data->answertext, 1);
					if (strlen($data->imagefile)) $hasimages = 1;
					array_push($this->answers, new ASS_AnswerMultipleResponseImage($data->answertext, $data->points, $data->aorder, $data->points_unchecked, $data->imagefile));
				}
			}
		}
		$this->setGraphicalAnswerSetting($hasimages);
		parent::loadFromDb($question_id);
	}

	/**
	* Adds an answer to the question
	*
	* Adds an answer to the question
	*
	* @access public
	*/
	/*function addAnswer($answertext, $points, $answerorder, $correctness)
	{
		include_once "./Modules/TestQuestionPool/classes/class.assAnswerBinaryState.php";
		array_push($this->answers, new ASS_AnswerBinaryState($answertext, $points, $answerorder, $correctness));
	}*/
	
	/**
	* Duplicates an assMultipleChoiceQuestion
	*
	* Duplicates an assMultipleChoiceQuestion
	*
	* @access public
	*/
	function duplicate($for_test = true, $title = "", $author = "", $owner = "")
	{
		if ($this->id <= 0)
		{
			// The question has not been saved. It cannot be duplicated
			return;
		}
		// duplicate the question in database
		$this_id = $this->getId();
		$clone = $this;
		include_once ("./Modules/TestQuestionPool/classes/class.assQuestion.php");
		$original_id = assQuestion::_getOriginalId($this->id);
		$clone->id = -1;
		if ($title)
		{
			$clone->setTitle($title);
		}

		if ($author)
		{
			$clone->setAuthor($author);
		}
		if ($owner)
		{
			$clone->setOwner($owner);
		}

		if ($for_test)
		{
			$clone->saveToDb($original_id);
		}
		else
		{
			$clone->saveToDb();
		}

		// copy question page content
		$clone->copyPageOfQuestion($this_id);
		// copy XHTML media objects
		$clone->copyXHTMLMediaObjectsOfQuestion($this_id);
		// duplicate the images
		$clone->duplicateImages($this_id);
		// duplicate the generic feedback
		$clone->duplicateFeedbackGeneric($this_id);
		// duplicate the answer specific feedback
		$clone->duplicateFeedbackAnswer($this_id);

		return $clone->id;
	}

	/**
	* Copies an assMultipleChoice object
	*
	* Copies an assMultipleChoice object
	*
	* @access public
	*/
	function copyObject($target_questionpool, $title = "")
	{
		if ($this->id <= 0)
		{
			// The question has not been saved. It cannot be duplicated
			return;
		}
		// duplicate the question in database
		$clone = $this;
		include_once ("./Modules/TestQuestionPool/classes/class.assQuestion.php");
		$original_id = assQuestion::_getOriginalId($this->id);
		$clone->id = -1;
		$source_questionpool = $this->getObjId();
		$clone->setObjId($target_questionpool);
		if ($title)
		{
			$clone->setTitle($title);
		}
		$clone->saveToDb();

		// copy question page content
		$clone->copyPageOfQuestion($original_id);
		// copy XHTML media objects
		$clone->copyXHTMLMediaObjectsOfQuestion($original_id);
		// duplicate the image
		$clone->copyImages($original_id, $source_questionpool);
		// duplicate the generic feedback
		$clone->duplicateFeedbackGeneric($original_id);
		// duplicate the answer specific feedback
		$clone->duplicateFeedbackAnswer($original_id);

		return $clone->id;
	}

	/**
	* Gets the multiple choice output type
	*
	* Gets the multiple choice output type which is either OUTPUT_ORDER (=0) or OUTPUT_RANDOM (=1).
	*
	* @return integer The output type of the assMultipleChoice object
	* @access public
	* @see $output_type
	*/
	function getOutputType()
	{
		return $this->output_type;
	}

	/**
	* Sets the multiple choice output type
	*
	* Sets the output type of the assMultipleChoice object
	*
	* @param integer $output_type A nonnegative integer value specifying the output type. It is OUTPUT_ORDER (=0) or OUTPUT_RANDOM (=1).
	* @access public
	* @see $response
	*/
	function setOutputType($output_type = OUTPUT_ORDER)
	{
		$this->output_type = $output_type;
	}

	/**
	* Adds a possible answer for a multiple choice question
	*
	* Adds a possible answer for a multiple choice question. A ASS_AnswerBinaryStateImage object will be
	* created and assigned to the array $this->answers.
	*
	* @param string $answertext The answer text
	* @param double $points The points for selecting the answer (even negative points can be used)
	* @param boolean $state Defines the answer as correct (TRUE) or incorrect (FALSE)
	* @param integer $order A possible display order of the answer
	* @param double $points The points for not selecting the answer (even negative points can be used)
	* @access public
	* @see $answers
	* @see ASS_AnswerBinaryStateImage
	*/
	function addAnswer(
		$answertext = "",
		$points = 0.0,
		$points_unchecked = 0.0,
		$order = 0,
		$answerimage = ""
	)
	{
		$found = -1;
		foreach ($this->answers as $key => $value)
		{
			if ($value->getOrder() == $order)
			{
				$found = $order;
			}
		}
		include_once "./Modules/TestQuestionPool/classes/class.assAnswerMultipleResponseImage.php";
		if ($found >= 0)
		{
			// Antwort einfügen
			$answer = new ASS_AnswerMultipleResponseImage($answertext, $points, $found, $points_unchecked, $answerimage);
			array_push($this->answers, $answer);
			for ($i = $found + 1; $i < count($this->answers); $i++)
			{
				$this->answers[$i] = $this->answers[$i-1];
			}
			$this->answers[$found] = $answer;
		}
		else
		{
			// Anwort anhängen
			$answer = new ASS_AnswerMultipleResponseImage($answertext, $points, count($this->answers), $points_unchecked, $answerimage);
			array_push($this->answers, $answer);
		}
	}

	/**
	* Returns the number of answers
	*
	* Returns the number of answers
	*
	* @return integer The number of answers of the multiple choice question
	* @access public
	* @see $answers
	*/
	function getAnswerCount()
	{
		return count($this->answers);
	}

	/**
	* Returns an answer
	*
	* Returns an answer with a given index. The index of the first
	* answer is 0, the index of the second answer is 1 and so on.
	*
	* @param integer $index A nonnegative index of the n-th answer
	* @return object ASS_AnswerBinaryStateImage-Object containing the answer
	* @access public
	* @see $answers
	*/
	function getAnswer($index = 0)
	{
		if ($index < 0) return NULL;
		if (count($this->answers) < 1) return NULL;
		if ($index >= count($this->answers)) return NULL;

		return $this->answers[$index];
	}

	/**
	* Deletes an answer
	*
	* Deletes an answer with a given index. The index of the first
	* answer is 0, the index of the second answer is 1 and so on.
	*
	* @param integer $index A nonnegative index of the n-th answer
	* @access public
	* @see $answers
	*/
	function deleteAnswer($index = 0)
	{
		if ($index < 0) return;
		if (count($this->answers) < 1) return;
		if ($index >= count($this->answers)) return;
		$answer = $this->answers[$index];
		if (strlen($answer->getImage())) $this->deleteImage($answer->getImage());
		unset($this->answers[$index]);
		$this->answers = array_values($this->answers);
		for ($i = 0; $i < count($this->answers); $i++)
		{
			if ($this->answers[$i]->getOrder() > $index)
			{
				$this->answers[$i]->setOrder($i);
			}
		}
	}

	/**
	* Deletes all answers
	*
	* Deletes all answers
	*
	* @access public
	* @see $answers
	*/
	function flushAnswers()
	{
		$this->answers = array();
	}

	/**
	* Returns the maximum points, a learner can reach answering the question
	*
	* Returns the maximum points, a learner can reach answering the question
	*
	* @access public
	* @see $points
	*/
	function getMaximumPoints()
	{
		$points = 0;
		$allpoints = 0;
		foreach ($this->answers as $key => $value) 
		{
			if ($value->getPoints() > $value->getPointsUnchecked())
			{
				$allpoints += $value->getPoints();
			}
			else
			{
				$allpoints += $value->getPointsUnchecked();
			}
		}
		return $allpoints;
	}

	/**
	* Returns the points, a learner has reached answering the question
	*
	* Returns the points, a learner has reached answering the question
	* The points are calculated from the given answers including checks
	* for all special scoring options in the test container.
	*
	* @param integer $user_id The database ID of the learner
	* @param integer $test_id The database Id of the test containing the question
	* @access public
	*/
	function calculateReachedPoints($active_id, $pass = NULL)
	{
		global $ilDB;
		
		$found_values = array();
		if (is_null($pass))
		{
			$pass = $this->getSolutionMaxPass($active_id);
		}
		$query = sprintf("SELECT * FROM tst_solutions WHERE active_fi = %s AND question_fi = %s AND pass = %s",
			$ilDB->quote($active_id . ""),
			$ilDB->quote($this->getId() . ""),
			$ilDB->quote($pass . "")
		);
		$result = $ilDB->query($query);
		while ($data = $result->fetchRow(MDB2_FETCHMODE_OBJECT))
		{
			if (strcmp($data->value1, "") != 0)
			{
				array_push($found_values, $data->value1);
			}
		}
		$points = 0;
		foreach ($this->answers as $key => $answer)
		{
			if (in_array($key, $found_values))
			{
				$points += $answer->getPoints();
			}
			else
			{
				$points += $answer->getPointsUnchecked();
			}
		}
		include_once "./Modules/Test/classes/class.ilObjTest.php";
		$mc_scoring = ilObjTest::_getMCScoring($active_id);
		if (($mc_scoring == 0) && (count($found_values) == 0))
		{
			$points = 0;
		}
		$points = parent::calculateReachedPoints($active_id, $pass = NULL, $points);
		return $points;
	}
	
	/**
	* Saves the learners input of the question to the database
	*
	* Saves the learners input of the question to the database
	*
	* @param integer $test_id The database id of the test containing this question
  * @return boolean Indicates the save status (true if saved successful, false otherwise)
	* @access public
	* @see $answers
	*/
	function saveWorkingData($active_id, $pass = NULL)
	{
		global $ilDB;
		global $ilUser;

		if (is_null($pass))
		{
			include_once "./Modules/Test/classes/class.ilObjTest.php";
			$pass = ilObjTest::_getPass($active_id);
		}

		$entered_values = 0;
		$query = sprintf("DELETE FROM tst_solutions WHERE active_fi = %s AND question_fi = %s AND pass = %s",
			$ilDB->quote($active_id . ""),
			$ilDB->quote($this->getId() . ""),
			$ilDB->quote($pass . "")
		);
		$result = $ilDB->query($query);
		foreach ($_POST as $key => $value)
		{
			if (preg_match("/^multiple_choice_result_(\d+)/", $key, $matches))
			{
				if (strlen($value))
				{
					$query = sprintf("INSERT INTO tst_solutions (solution_id, active_fi, question_fi, value1, value2, pass, TIMESTAMP) VALUES (NULL, %s, %s, %s, NULL, %s, NULL)",
						$ilDB->quote($active_id),
						$ilDB->quote($this->getId()),
						$ilDB->quote($value),
						$ilDB->quote($pass . "")
					);
					$result = $ilDB->query($query);
					$entered_values++;
				}
			}
		}
		if ($entered_values)
		{
			include_once ("./Modules/Test/classes/class.ilObjAssessmentFolder.php");
			if (ilObjAssessmentFolder::_enabledAssessmentLogging())
			{
				$this->logAction($this->lng->txtlng("assessment", "log_user_entered_values", ilObjAssessmentFolder::_getLogLanguage()), $active_id, $this->getId());
			}
		}
		else
		{
			include_once ("./Modules/Test/classes/class.ilObjAssessmentFolder.php");
			if (ilObjAssessmentFolder::_enabledAssessmentLogging())
			{
				$this->logAction($this->lng->txtlng("assessment", "log_user_not_entered_values", ilObjAssessmentFolder::_getLogLanguage()), $active_id, $this->getId());
			}
		}
    parent::saveWorkingData($active_id, $pass);
		return true;
	}

	/**
	* Synchronizes the single answer feedback with an original question
	*
	* Synchronizes the single answer feedback with an original question
	*
	* @access public
	*/
	function syncFeedbackSingleAnswers()
	{
		global $ilDB;

		$feedback = "";

		// delete generic feedback of the original
		$deletequery = sprintf("DELETE FROM qpl_feedback_multiplechoice WHERE question_fi = %s",
			$ilDB->quote($this->original_id . "")
		);
		$result = $ilDB->query($deletequery);
			
		// get generic feedback of the actual question
		$query = sprintf("SELECT * FROM qpl_feedback_multiplechoice WHERE question_fi = %s",
			$ilDB->quote($this->getId() . "")
		);
		$result = $ilDB->query($query);

		// save generic feedback to the original
		if ($result->numRows())
		{
			while ($row = $result->fetchRow(MDB2_FETCHMODE_ASSOC))
			{
				$duplicatequery = sprintf("INSERT INTO qpl_feedback_multiplechoice VALUES (NULL, %s, %s, %s, NULL)",
					$ilDB->quote($this->original_id . ""),
					$ilDB->quote($row["answer"] . ""),
					$ilDB->quote($row["feedback"] . "")
				);
				$duplicateresult = $ilDB->query($duplicatequery);
			}
		}
	}

	function syncWithOriginal()
	{
		if ($this->getOriginalId())
		{
			$this->syncFeedbackSingleAnswers();
			$this->syncImages();
			parent::syncWithOriginal();
		}
	}

	/**
	* Returns the question type of the question
	*
	* Returns the question type of the question
	*
	* @return integer The question type of the question
	* @access public
	*/
	function getQuestionType()
	{
		return "assMultipleChoice";
	}
	
	/**
	* Returns the name of the additional question data table in the database
	*
	* Returns the name of the additional question data table in the database
	*
	* @return string The additional table name
	* @access public
	*/
	function getAdditionalTableName()
	{
		return "qpl_question_multiplechoice";
	}
	
	/**
	* Returns the name of the answer table in the database
	*
	* Returns the name of the answer table in the database
	*
	* @return string The answer table name
	* @access public
	*/
	function getAnswerTableName()
	{
		return "qpl_answer_multiplechoice";
	}
	
	function getGraphicalAnswerSetting()
	{
		global $ilUser;

		$graphicalAnswerSetting = $ilUser->getPref("graphicalAnswerSetting");
		if ($graphicalAnswerSetting != 1)
		{
			$graphicalAnswerSetting = 0;
		}
		return $graphicalAnswerSetting;
	}
	
	function setGraphicalAnswerSetting($a_setting = 0)
	{
		global $ilUser;
		$ilUser->writePref("graphicalAnswerSetting", $a_setting);
	}

	/**
	* Sets the image file
	*
	* Sets the image file and uploads the image to the object's image directory.
	*
	* @param string $image_filename Name of the original image file
	* @param string $image_tempfilename Name of the temporary uploaded image file
	* @return integer An errorcode if the image upload fails, 0 otherwise
	* @access public
	*/
	function setImageFile($image_filename, $image_tempfilename = "")
	{
		$result = 0;
		if (!empty($image_tempfilename))
		{
			$image_filename = str_replace(" ", "_", $image_filename);
			$imagepath = $this->getImagePath();
			if (!file_exists($imagepath))
			{
				ilUtil::makeDirParents($imagepath);
			}
			//if (!move_uploaded_file($image_tempfilename, $imagepath . $image_filename))
			if (!ilUtil::moveUploadedFile($image_tempfilename, $image_filename, $imagepath.$image_filename))
			{
				$result = 2;
			}
			else
			{
				include_once "./Services/MediaObjects/classes/class.ilObjMediaObject.php";
				$mimetype = ilObjMediaObject::getMimeType($imagepath . $image_filename);
				if (!preg_match("/^image/", $mimetype))
				{
					unlink($imagepath . $image_filename);
					$result = 1;
				}
				else
				{
					// create thumbnail file
					$thumbpath = $imagepath . $image_filename . "." . "thumb.jpg";
					ilUtil::convertImage($imagepath.$image_filename, $thumbpath, "JPEG", 100);
				}
			}
		}
		return $result;
	}
	
	/**
	* Deletes an image file
	*
	* Deletes an image file
	*
	* @param string $image_filename Name of the image file to delete
	* @access private
	*/
	function deleteImage($image_filename)
	{
		$imagepath = $this->getImagePath();
		unlink($imagepath . $image_filename);
		$thumbpath = $imagepath . $image_filename . "." . "thumb.jpg";
		unlink($thumbpath);
	}

	function duplicateImages($question_id)
	{
		global $ilLog;
		$imagepath = $this->getImagePath();
		$imagepath_original = str_replace("/$this->id/images", "/$question_id/images", $imagepath);
		if (!file_exists($imagepath))
		{
			ilUtil::makeDirParents($imagepath);
		}
		foreach ($this->answers as $answer)
		{
			$filename = $answer->getImage();
			if (strlen($filename))
			{
				if (!copy($imagepath_original . $filename, $imagepath . $filename))
				{
					$ilLog->write("image could not be duplicated!!!!", $ilLog->ERROR);
					$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
				}
				if (!copy($imagepath_original . $filename . ".thumb.jpg", $imagepath . $filename . ".thumb.jpg"))
				{
					$ilLog->write("image thumbnail could not be duplicated!!!!", $ilLog->ERROR);
					$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
				}
			}
		}
	}

	function copyImages($question_id, $source_questionpool)
	{
		global $ilLog;
		$imagepath = $this->getImagePath();
		$imagepath_original = str_replace("/$this->id/images", "/$question_id/images", $imagepath);
		$imagepath_original = str_replace("/$this->obj_id/", "/$source_questionpool/", $imagepath_original);
		if (!file_exists($imagepath))
		{
			ilUtil::makeDirParents($imagepath);
		}
		foreach ($this->answers as $answer)
		{
			$filename = $answer->getImage();
			if (strlen($filename))
			{
				if (!copy($imagepath_original . $filename, $imagepath . $filename))
				{
					$ilLog->write("image could not be duplicated!!!!", $ilLog->ERROR);
					$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
				}
				if (!copy($imagepath_original . $filename . ".thumb.jpg", $imagepath . $filename . ".thumb.jpg"))
				{
					$ilLog->write("image thumbnail could not be duplicated!!!!", $ilLog->ERROR);
					$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
				}
			}
		}
	}

	/**
	* Sync images of a MC question on synchronisation with the original question
	**/
	protected function syncImages()
	{
		global $ilLog;
		$question_id = $this->getOriginalId();
		$imagepath = $this->getImagePath();
		$imagepath_original = str_replace("/$this->id/images", "/$question_id/images", $imagepath);
		if (!file_exists($imagepath))
		{
			ilUtil::makeDirParents($imagepath);
		}
		ilUtil::delDir($imagepath_original);
		ilUtil::makeDirParents($imagepath_original);
		foreach ($this->answers as $answer)
		{
			$filename = $answer->getImage();
			if (strlen($filename))
			{
				if (@file_exists($imagepath . $filename))
				{
					if (!@copy($imagepath . $filename, $imagepath_original . $filename))
					{
						$ilLog->write("image could not be duplicated!!!!", $ilLog->ERROR);
						$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
					}
				}
				if (@file_exists($imagepath . $filename . ".thumb.jpg"))
				{
					if (!@copy($imagepath . $filename . ".thumb.jpg", $imagepath_original . $filename . ".thumb.jpg"))
					{
						$ilLog->write("image thumbnail could not be duplicated!!!!", $ilLog->ERROR);
						$ilLog->write("object: " . print_r($this, TRUE), $ilLog->ERROR);
					}
				}
			}
		}
	}

	/**
	* Saves feedback for a single selected answer to the database
	*
	* Saves feedback for a single selected answer to the database
	*
	* @param integer $answer_index The index of the answer
	* @param string $feedback Feedback text
	* @access public
	*/
	function saveFeedbackSingleAnswer($answer_index, $feedback)
	{
		global $ilDB;
		
		$query = sprintf("DELETE FROM qpl_feedback_multiplechoice WHERE question_fi = %s AND answer = %s",
			$ilDB->quote($this->getId() . ""),
			$ilDB->quote($answer_index . "")
		);
		$result = $ilDB->query($query);
		if (strlen($feedback))
		{
			include_once("./Services/RTE/classes/class.ilRTE.php");
			$query = sprintf("INSERT INTO qpl_feedback_multiplechoice VALUES (NULL, %s, %s, %s, NULL)",
				$ilDB->quote($this->getId() . ""),
				$ilDB->quote($answer_index . ""),
				$ilDB->quote(ilRTE::_replaceMediaObjectImageSrc($feedback, 0))
			);
			$result = $ilDB->query($query);
		}
	}

	/**
	* Returns the feedback for a single selected answer
	*
	* Returns the feedback for a single selected answer
	*
	* @param integer $answer_index The index of the answer
	* @return string Feedback text
	* @access public
	*/
	function getFeedbackSingleAnswer($answer_index)
	{
		global $ilDB;
		
		$feedback = "";
		$query = sprintf("SELECT * FROM qpl_feedback_multiplechoice WHERE question_fi = %s AND answer = %s",
			$ilDB->quote($this->getId() . ""),
			$ilDB->quote($answer_index . "")
		);
		$result = $ilDB->query($query);
		if ($result->numRows())
		{
			$row = $result->fetchRow(MDB2_FETCHMODE_ASSOC);
			include_once("./Services/RTE/classes/class.ilRTE.php");
			$feedback = ilRTE::_replaceMediaObjectImageSrc($row["feedback"], 1);
		}
		return $feedback;
	}

	/**
	* Duplicates the answer specific feedback
	*
	* Duplicates the answer specific feedback
	*
	* @param integer $original_id The database ID of the original question
	* @access public
	*/
	function duplicateFeedbackAnswer($original_id)
	{
		global $ilDB;
		
		$feedback = "";
		$query = sprintf("SELECT * FROM qpl_feedback_multiplechoice WHERE question_fi = %s",
			$ilDB->quote($original_id . "")
		);
		$result = $ilDB->query($query);
		if ($result->numRows())
		{
			while ($row = $result->fetchRow(MDB2_FETCHMODE_ASSOC))
			{
				$duplicatequery = sprintf("INSERT INTO qpl_feedback_multiplechoice VALUES (NULL, %s, %s, %s, NULL)",
					$ilDB->quote($this->getId() . ""),
					$ilDB->quote($row["answer"] . ""),
					$ilDB->quote($row["feedback"] . "")
				);
				$duplicateresult = $ilDB->query($duplicatequery);
			}
		}
	}

	/**
	* Collects all text in the question which could contain media objects
	* which were created with the Rich Text Editor
	*/
	function getRTETextWithMediaObjects()
	{
		$text = parent::getRTETextWithMediaObjects();
		foreach ($this->answers as $index => $answer)
		{
			$text .= $this->getFeedbackSingleAnswer($index);
			$answer_obj = $this->answers[$index];
			$text .= $answer_obj->getAnswertext();
		}
		return $text;
	}
	
	/**
	* Returns a reference to the answers array
	*/
	function &getAnswers()
	{
		return $this->answers;
	}

	/**
	* Creates an Excel worksheet for the detailed cumulated results of this question
	*
	* @param object $worksheet Reference to the parent excel worksheet
	* @param object $startrow Startrow of the output in the excel worksheet
	* @param object $active_id Active id of the participant
	* @param object $pass Test pass
	* @param object $format_title Excel title format
	* @param object $format_bold Excel bold format
	* @param array $eval_data Cumulated evaluation data
	* @access public
	*/
	public function setExportDetailsXLS(&$worksheet, $startrow, $active_id, $pass, &$format_title, &$format_bold)
	{
		include_once ("./classes/class.ilExcelUtils.php");
		$solution = $this->getSolutionValues($active_id, $pass);
		$worksheet->writeString($startrow, 0, ilExcelUtils::_convert_text($this->lng->txt($this->getQuestionType())), $format_title);
		$worksheet->writeString($startrow, 1, ilExcelUtils::_convert_text($this->getTitle()), $format_title);
		$i = 1;
		foreach ($this->getAnswers() as $id => $answer)
		{
			$worksheet->writeString($startrow + $i, 0, ilExcelUtils::_convert_text($answer->getAnswertext()), $format_bold);
			$checked = FALSE;
			foreach ($solution as $solutionvalue)
			{
				if ($id == $solutionvalue["value1"])
				{
					$checked = TRUE;
				}
			}
			if ($checked)
			{
				$worksheet->write($startrow + $i, 1, 1);
			}
			else
			{
				$worksheet->write($startrow + $i, 1, 0);
			}
			$i++;
		}
		return $startrow + $i + 1;
	}
}

?>
