assessment/classes/class.ilObjQuestionPool.php

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<?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 "./assessment/classes/inc.AssessmentConstants.php";

class ilObjQuestionPool extends ilObject
{
        var $online;

        function ilObjQuestionPool($a_id = 0,$a_call_by_reference = true)
        {
                $this->type = "qpl";
                $this->ilObject($a_id,$a_call_by_reference);
                $this->setOnline(0);
        }

        function create($a_upload = false)
        {
                parent::create();

                // meta data will be created by
                // import parser
                if (!$a_upload)
                {
                        $this->createMetaData();
                }
        }

        function createReference()
        {
                $result = parent::createReference();
                $this->saveToDb();
                return $result;
        }

        function update()
        {
                $this->updateMetaData();
                if (!parent::update())
                {
                        return false;
                }

                // put here object specific stuff

                return true;
        }

        function updateMetaData()
        {
                global $ilUser;
                include_once "./Services/MetaData/classes/class.ilMD.php";
                $md =& new ilMD($this->getId(), 0, $this->getType());
                $md_gen =& $md->getGeneral();
                if ($md_gen == false)
                {
                        include_once "./Services/MetaData/classes/class.ilMDCreator.php";
                        $md_creator = new ilMDCreator($this->getId(),0,$this->getType());
                        $md_creator->setTitle($this->getTitle());
                        $md_creator->setTitleLanguage($ilUser->getPref('language'));
                        $md_creator->create();
                }
                parent::updateMetaData();
        }

        function read($a_force_db = false)
        {
                parent::read($a_force_db);
                $this->loadFromDb();
        }

        function ilClone($a_parent_ref)
        {
                global $rbacadmin;

                // always call parent ilClone function first!!
                $new_ref_id = parent::ilClone($a_parent_ref);

                // get object instance of ilCloned object
                //$newObj =& $this->ilias->obj_factory->getInstanceByRefId($new_ref_id);

                // create a local role folder & default roles
                //$roles = $newObj->initDefaultRoles();

                // ...finally assign role to creator of object
                //$rbacadmin->assignUser($roles[0], $newObj->getOwner(), "n");

                // always destroy objects in ilClone method because ilClone() is recursive and creates instances for each object in subtree!
                //unset($newObj);

                // ... and finally always return new reference ID!!
                return $new_ref_id;
        }

        function delete()
        {
/*              $questions =& $this->getAllQuestions();
                $used_questions = 0;
                include_once "./assessment/classes/class.assQuestion.php";
                foreach ($questions as $question_id)
                {
                        if (assQuestion::_isUsedInRandomTest($question_id))
                        {
                                $used_questions++;
                        }
                }

                if ($used_questions)
                {
                        return false;
                }
*/
                // always call parent delete function first!!
                if (!parent::delete())
                {
                        return false;
                }

                // delete meta data
                $this->deleteMetaData();

                //put here your module specific stuff
                $this->deleteQuestionpool();

                return true;
        }

        function deleteQuestionpool()
        {
                $questions =& $this->getAllQuestions();

                if (count($questions))
                {
                        foreach ($questions as $question_id)
                        {
                                $this->deleteQuestion($question_id);
                        }
                }

                // delete export files
                include_once "./classes/class.ilUtil.php";
                $qpl_data_dir = ilUtil::getDataDir()."/qpl_data";
                $directory = $qpl_data_dir."/qpl_".$this->getId();
                if (is_dir($directory))
                {
                        include_once "./classes/class.ilUtil.php";
                        ilUtil::delDir($directory);
                }
        }

        function initDefaultRoles()
        {
                global $rbacadmin;

                // create a local role folder
                //$rfoldObj = $this->createRoleFolder("Local roles","Role Folder of forum obj_no.".$this->getId());

                // create moderator role and assign role to rolefolder...
                //$roleObj = $rfoldObj->createRole("Moderator","Moderator of forum obj_no.".$this->getId());
                //$roles[] = $roleObj->getId();

                //unset($rfoldObj);
                //unset($roleObj);

                return $roles ? $roles : array();
        }

        function notify($a_event,$a_ref_id,$a_parent_non_rbac_id,$a_node_id,$a_params = 0)
        {
                global $tree;

                switch ($a_event)
                {
                        case "link":

                                //var_dump("<pre>",$a_params,"</pre>");
                                //echo "Module name ".$this->getRefId()." triggered by link event. Objects linked into target object ref_id: ".$a_ref_id;
                                //exit;
                                break;

                        case "cut":

                                //echo "Module name ".$this->getRefId()." triggered by cut event. Objects are removed from target object ref_id: ".$a_ref_id;
                                //exit;
                                break;

                        case "copy":

                                //var_dump("<pre>",$a_params,"</pre>");
                                //echo "Module name ".$this->getRefId()." triggered by copy event. Objects are copied into target object ref_id: ".$a_ref_id;
                                //exit;
                                break;

                        case "paste":

                                //echo "Module name ".$this->getRefId()." triggered by paste (cut) event. Objects are pasted into target object ref_id: ".$a_ref_id;
                                //exit;
                                break;

                        case "new":

                                //echo "Module name ".$this->getRefId()." triggered by paste (new) event. Objects are applied to target object ref_id: ".$a_ref_id;
                                //exit;
                                break;
                }

                // At the beginning of the recursive process it avoids second call of the notify function with the same parameter
                if ($a_node_id==$_GET["ref_id"])
                {
                        $parent_obj =& $this->ilias->obj_factory->getInstanceByRefId($a_node_id);
                        $parent_type = $parent_obj->getType();
                        if($parent_type == $this->getType())
                        {
                                $a_node_id = (int) $tree->getParentId($a_node_id);
                        }
                }

                parent::notify($a_event,$a_ref_id,$a_parent_non_rbac_id,$a_node_id,$a_params);
        }

        function deleteQuestion($question_id)
        {
                include_once "./assessment/classes/class.ilObjTest.php";
                $question =& ilObjTest::_instanciateQuestion($question_id);
                $question->delete($question_id);
        }

        function loadFromDb()
        {
                global $ilDB;

                $query = sprintf("SELECT * FROM qpl_questionpool WHERE obj_fi = %s",
                        $ilDB->quote($this->getId() . "")
                );
                $result = $ilDB->query($query);
                if ($result->numRows() == 1)
                {
                        $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                        $this->setOnline($row["online"]);
                }
        }

  function saveToDb()
  {
                global $ilDB;

                $query = sprintf("SELECT * FROM qpl_questionpool WHERE obj_fi = %s",
                        $ilDB->quote($this->getId() . "")
                );
                $result = $ilDB->query($query);
                if ($result->numRows() == 1)
                {
                        $query = sprintf("UPDATE qpl_questionpool SET online = %s WHERE obj_fi = %s",
                                $ilDB->quote($this->getOnline() . ""),
                                $ilDB->quote($this->getId() . "")
                        );
      $result = $ilDB->query($query);
      if ($result != DB_OK)
                        {
      }
                }
                else
                {
                        $query = sprintf("INSERT INTO qpl_questionpool (online, obj_fi) VALUES (%s, %s)",
                                $ilDB->quote($this->getOnline() . ""),
                                $ilDB->quote($this->getId() . "")
                        );
      $result = $ilDB->query($query);
      if ($result != DB_OK)
                        {
      }
                }
        }

        function getQuestiontype($question_id)
        {
                global $ilDB;

                if ($question_id < 1)
                {
                        return;
                }

                $query = sprintf("SELECT qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE qpl_questions.question_type_fi = qpl_question_type.question_type_id AND qpl_questions.question_id = %s",
                        $ilDB->quote($question_id));

                $result = $ilDB->query($query);
                if ($result->numRows() == 1)
                {
                        $data = $result->fetchRow(DB_FETCHMODE_OBJECT);
                        return $data->type_tag;
                }
                else
                {
                        return;
                }
        }

        function getDescription()
        {
                return parent::getDescription();
        }

        function setDescription($a_description)
        {
                parent::setDescription($a_description);
        }

        function getTitle()
        {
                return parent::getTitle();
        }

        function setTitle($a_title)
        {
                parent::setTitle($a_title);
        }

        function isInUse($question_id)
        {
                global $ilDB;

                $query = sprintf("SELECT COUNT(solution_id) AS solution_count FROM tst_solutions WHERE question_fi = %s",
                        $ilDB->quote("$question_id"));

                $result = $ilDB->query($query);
                $row = $result->fetchRow(DB_FETCHMODE_OBJECT);

                return $row->solution_count;
        }

        function &createQuestion($question_type, $question_id = -1)
        {
                if ((!$question_type) and ($question_id > 0))
                {
                        $question_type = $this->getQuestiontype($question_id);
                }

                include_once "./assessment/classes/class.".$question_type."GUI.php";
                $question_type_gui = $question_type . "GUI";
                $question =& new $question_type_gui();

                if ($question_id > 0)
                {
                        $question->object->loadFromDb($question_id);
                }

                return $question;
        }

        function duplicateQuestion($question_id)
        {
                $question =& $this->createQuestion("", $question_id);
                $newtitle = $question->object->getTitle();
                if ($question->object->questionTitleExists($this->getId(), $question->object->getTitle()))
                {
                        $counter = 2;
                        while ($question->object->questionTitleExists($this->getId(), $question->object->getTitle() . " ($counter)"))
                        {
                                $counter++;
                        }
                        $newtitle = $question->object->getTitle() . " ($counter)";
                }
                $question->object->duplicate(false, $newtitle);
                // update question count of question pool
                ilObjQuestionPool::_updateQuestionCount($this->getId());
        }

        function copyQuestion($question_id, $questionpool_to)
        {
                $question_gui =& $this->createQuestion("", $question_id);
                if ($question_gui->object->getObjId() == $questionpool_to)
                {
                        // the question is copied into the same question pool
                        $this->duplicateQuestion($question_id);
                }
                else
                {
                        // the question is copied into another question pool
                        $newtitle = $question_gui->object->getTitle();
                        if ($question_gui->object->questionTitleExists($this->getId(), $question_gui->object->getTitle()))
                        {
                                $counter = 2;
                                while ($question_gui->object->questionTitleExists($this->getId(), $question_gui->object->getTitle() . " ($counter)"))
                                {
                                        $counter++;
                                }
                                $newtitle = $question_gui->object->getTitle() . " ($counter)";
                        }
                        $question_gui->object->copyObject($this->getId(), $newtitle);
                }
        }

        function getQuestionsTable($sort, $sortorder, $filter_text, $sel_filter_type, $startrow = 0)
        {
                global $ilUser;
                global $ilDB;

                $where = "";
                if (strlen($filter_text) > 0)
                {
                        switch($sel_filter_type)
                        {
                                case "title":
                                        $where = " AND qpl_questions.title LIKE " . $ilDB->quote("%" . $filter_text . "%");
                                        break;

                                case "comment":
                                        $where = " AND qpl_questions.comment LIKE " . $ilDB->quote("%" . $filter_text . "%");
                                        break;

                                case "author":
                                        $where = " AND qpl_questions.author LIKE " . $ilDB->quote("%" . $filter_text . "%");
                                        break;
                        }
                }

            // build sort order for sql query
                $order = "";
                $images = array();
                include_once "./classes/class.ilUtil.php";
                switch($sort)
                {
                        case "title":
                                $order = " ORDER BY title $sortorder";
                                $images["title"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                        case "comment":
                                $order = " ORDER BY comment $sortorder";
                                $images["comment"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                        case "type":
                                $order = " ORDER BY question_type_id $sortorder";
                                $images["type"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                        case "author":
                                $order = " ORDER BY author $sortorder";
                                $images["author"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                        case "created":
                                $order = " ORDER BY created $sortorder";
                                $images["created"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                        case "updated":
                                $order = " ORDER BY TIMESTAMP14 $sortorder";
                                $images["updated"] = " <img src=\"" . ilUtil::getImagePath(strtolower($sortorder) . "_order.gif") . "\" alt=\"" . $this->lng->txt(strtolower($sortorder) . "ending_order")."\" />";
                                break;
                }
                $maxentries = $ilUser->prefs["hits_per_page"];
                if ($maxentries < 1)
                {
                        $maxentries = 9999;
                }
                $query = "SELECT qpl_questions.question_id, qpl_questions.TIMESTAMP + 0 AS TIMESTAMP14 FROM qpl_questions, qpl_question_type WHERE ISNULL(qpl_questions.original_id) AND qpl_questions.question_type_fi = qpl_question_type.question_type_id AND qpl_questions.obj_fi = " . $this->getId() . " $where$order$limit";
                $query_result = $ilDB->query($query);
                $max = $query_result->numRows();
                if ($startrow > $max -1)
                {
                        $startrow = $max - ($max % $maxentries);
                }
                else if ($startrow < 0)
                {
                        $startrow = 0;
                }
                $limit = " LIMIT $startrow, $maxentries";
                $query = "SELECT qpl_questions.*, qpl_questions.TIMESTAMP + 0 AS TIMESTAMP14, qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE ISNULL(qpl_questions.original_id) AND qpl_questions.question_type_fi = qpl_question_type.question_type_id AND qpl_questions.obj_fi = " . $this->getId() . " $where$order$limit";
                $query_result = $ilDB->query($query);
                $rows = array();
                if ($query_result->numRows())
                {
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                array_push($rows, $row);
                        }
                }
                $nextrow = $startrow + $maxentries;
                if ($nextrow > $max - 1)
                {
                        $nextrow = $startrow;
                }
                $prevrow = $startrow - $maxentries;
                if ($prevrow < 0)
                {
                        $prevrow = 0;
                }
                return array(
                        "rows" => $rows,
                        "images" => $images,
                        "startrow" => $startrow,
                        "nextrow" => $nextrow,
                        "prevrow" => $prevrow,
                        "step" => $maxentries,
                        "rowcount" => $max
                );
        }

        function &getPrintviewQuestions($sort)
        {
                global $ilDB;

            // build sort order for sql query
                $order = "";
                switch($sort)
                {
                        case "title":
                                $order = " ORDER BY title";
                                break;
                        case "comment":
                                $order = " ORDER BY comment,title";
                                break;
                        case "type":
                                $order = " ORDER BY question_type_id,title";
                                break;
                        case "author":
                                $order = " ORDER BY author,title";
                                break;
                        case "created":
                                $order = " ORDER BY created,title";
                                break;
                        case "updated":
                                $order = " ORDER BY TIMESTAMP14,title";
                                break;
                }
                $query = "SELECT qpl_questions.*, qpl_questions.TIMESTAMP + 0 AS TIMESTAMP14, qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE ISNULL(qpl_questions.original_id) AND qpl_questions.question_type_fi = qpl_question_type.question_type_id AND qpl_questions.obj_fi = " . $this->getId() . " $order";
                $query_result = $ilDB->query($query);
                $rows = array();
                if ($query_result->numRows())
                {
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                array_push($rows, $row);
                        }
                }
                return $rows;
        }

        function exportPagesXML(&$a_xml_writer, $a_inst, $a_target_dir, &$expLog, $questions)
        {
                global $ilBench;

                $this->mob_ids = array();
                $this->file_ids = array();

                $attrs = array();
                $attrs["Type"] = "Questionpool_Test";
                $a_xml_writer->xmlStartTag("ContentObject", $attrs);

                // MetaData
                $this->exportXMLMetaData($a_xml_writer);

                // PageObjects
                $expLog->write(date("[y-m-d H:i:s] ")."Start Export Page Objects");
                $ilBench->start("ContentObjectExport", "exportPageObjects");
                $this->exportXMLPageObjects($a_xml_writer, $a_inst, $expLog, $questions);
                $ilBench->stop("ContentObjectExport", "exportPageObjects");
                $expLog->write(date("[y-m-d H:i:s] ")."Finished Export Page Objects");

                // MediaObjects
                $expLog->write(date("[y-m-d H:i:s] ")."Start Export Media Objects");
                $ilBench->start("ContentObjectExport", "exportMediaObjects");
                $this->exportXMLMediaObjects($a_xml_writer, $a_inst, $a_target_dir, $expLog);
                $ilBench->stop("ContentObjectExport", "exportMediaObjects");
                $expLog->write(date("[y-m-d H:i:s] ")."Finished Export Media Objects");

                // FileItems
                $expLog->write(date("[y-m-d H:i:s] ")."Start Export File Items");
                $ilBench->start("ContentObjectExport", "exportFileItems");
                $this->exportFileItems($a_target_dir, $expLog);
                $ilBench->stop("ContentObjectExport", "exportFileItems");
                $expLog->write(date("[y-m-d H:i:s] ")."Finished Export File Items");

                $a_xml_writer->xmlEndTag("ContentObject");
        }

        function exportXMLMetaData(&$a_xml_writer)
        {
                include_once("Services/MetaData/classes/class.ilMD2XML.php");
                $md2xml = new ilMD2XML($this->getId(), 0, $this->getType());
                $md2xml->setExportMode(true);
                $md2xml->startExport();
                $a_xml_writer->appendXML($md2xml->getXML());
        }

        function modifyExportIdentifier($a_tag, $a_param, $a_value)
        {
                if ($a_tag == "Identifier" && $a_param == "Entry")
                {
                        include_once "./classes/class.ilUtil.php";
                        $a_value = ilUtil::insertInstIntoID($a_value);
                }

                return $a_value;
        }


        function exportXMLPageObjects(&$a_xml_writer, $a_inst, &$expLog, $questions)
        {
                global $ilBench;

                include_once "./content/classes/class.ilLMPageObject.php";

                foreach ($questions as $question_id)
                {
                        $ilBench->start("ContentObjectExport", "exportPageObject");
                        $expLog->write(date("[y-m-d H:i:s] ")."Page Object ".$question_id);

                        $attrs = array();
                        $a_xml_writer->xmlStartTag("PageObject", $attrs);


                        // export xml to writer object
                        $ilBench->start("ContentObjectExport", "exportPageObject_XML");
                        $page_object = new ilPageObject("qpl", $question_id);
                        $page_object->buildDom();
                        $page_object->insertInstIntoIDs($a_inst);
                        $mob_ids = $page_object->collectMediaObjects(false);
                        $file_ids = $page_object->collectFileItems();
                        $xml = $page_object->getXMLFromDom(false, false, false, "", true);
                        $xml = str_replace("&","&amp;", $xml);
                        $a_xml_writer->appendXML($xml);
                        $page_object->freeDom();
                        unset ($page_object);

                        $ilBench->stop("ContentObjectExport", "exportPageObject_XML");

                        // collect media objects
                        $ilBench->start("ContentObjectExport", "exportPageObject_CollectMedia");
                        //$mob_ids = $page_obj->getMediaObjectIDs();
                        foreach($mob_ids as $mob_id)
                        {
                                $this->mob_ids[$mob_id] = $mob_id;
                        }
                        $ilBench->stop("ContentObjectExport", "exportPageObject_CollectMedia");

                        // collect all file items
                        $ilBench->start("ContentObjectExport", "exportPageObject_CollectFileItems");
                        //$file_ids = $page_obj->getFileItemIds();
                        foreach($file_ids as $file_id)
                        {
                                $this->file_ids[$file_id] = $file_id;
                        }
                        $ilBench->stop("ContentObjectExport", "exportPageObject_CollectFileItems");

                        $a_xml_writer->xmlEndTag("PageObject");
                        //unset($page_obj);

                        $ilBench->stop("ContentObjectExport", "exportPageObject");


                }
        }

        function exportXMLMediaObjects(&$a_xml_writer, $a_inst, $a_target_dir, &$expLog)
        {
                include_once("content/classes/Media/class.ilObjMediaObject.php");

                foreach ($this->mob_ids as $mob_id)
                {
                        $expLog->write(date("[y-m-d H:i:s] ")."Media Object ".$mob_id);
                        $media_obj = new ilObjMediaObject($mob_id);
                        $media_obj->exportXML($a_xml_writer, $a_inst);
                        $media_obj->exportFiles($a_target_dir);
                        unset($media_obj);
                }
        }

        function exportFileItems($a_target_dir, &$expLog)
        {
                include_once("classes/class.ilObjFile.php");

                foreach ($this->file_ids as $file_id)
                {
                        $expLog->write(date("[y-m-d H:i:s] ")."File Item ".$file_id);
                        $file_obj = new ilObjFile($file_id, false);
                        $file_obj->export($a_target_dir);
                        unset($file_obj);
                }
        }

        function createExportDirectory()
        {
                include_once "./classes/class.ilUtil.php";
                $qpl_data_dir = ilUtil::getDataDir()."/qpl_data";
                ilUtil::makeDir($qpl_data_dir);
                if(!is_writable($qpl_data_dir))
                {
                        $this->ilias->raiseError("Questionpool Data Directory (".$qpl_data_dir
                                .") not writeable.",$this->ilias->error_obj->FATAL);
                }

                // create learning module directory (data_dir/lm_data/lm_<id>)
                $qpl_dir = $qpl_data_dir."/qpl_".$this->getId();
                ilUtil::makeDir($qpl_dir);
                if(!@is_dir($qpl_dir))
                {
                        $this->ilias->raiseError("Creation of Questionpool Directory failed.",$this->ilias->error_obj->FATAL);
                }
                // create Export subdirectory (data_dir/lm_data/lm_<id>/Export)
                $export_dir = $qpl_dir."/export";
                ilUtil::makeDir($export_dir);
                if(!@is_dir($export_dir))
                {
                        $this->ilias->raiseError("Creation of Export Directory failed.",$this->ilias->error_obj->FATAL);
                }
        }

        function getExportDirectory()
        {
                include_once "./classes/class.ilUtil.php";
                $export_dir = ilUtil::getDataDir()."/qpl_data"."/qpl_".$this->getId()."/export";
                return $export_dir;
        }

        function getExportFiles($dir)
        {
                // quit if import dir not available
                if (!@is_dir($dir) or
                        !is_writeable($dir))
                {
                        return array();
                }
                // open directory
                $dir = dir($dir);

                // initialize array
                $file = array();

                // get files and save the in the array
                while ($entry = $dir->read())
                {
                        if ($entry != "." and
                                $entry != ".." and
                                (substr($entry, -4) == ".zip" or substr($entry, -4) == ".xls") and
                                ereg("^[0-9]{10}_{2}[0-9]+_{2}(qpl__)*[0-9]+\.(zip|xls)\$", $entry))
                        {
                                $file[] = $entry;
                        }
                }

                // close import directory
                $dir->close();

                // sort files
                sort ($file);
                reset ($file);
                return $file;
        }

        function _createImportDirectory()
        {
                global $ilias;

                include_once "./classes/class.ilUtil.php";
                $qpl_data_dir = ilUtil::getDataDir()."/qpl_data";
                ilUtil::makeDir($qpl_data_dir);

                if(!is_writable($qpl_data_dir))
                {
                        $ilias->raiseError("Questionpool Data Directory (".$qpl_data_dir
                                .") not writeable.",$ilias->error_obj->FATAL);
                }

                // create questionpool directory (data_dir/qpl_data/qpl_import)
                $qpl_dir = $qpl_data_dir."/qpl_import";
                ilUtil::makeDir($qpl_dir);
                if(!@is_dir($qpl_dir))
                {
                        $ilias->raiseError("Creation of Questionpool Directory failed.",$ilias->error_obj->FATAL);
                }
        }

        function _getImportDirectory()
        {
                include_once "./classes/class.ilUtil.php";
                $import_dir = ilUtil::getDataDir()."/qpl_data/qpl_import";
                if(@is_dir($import_dir))
                {
                        return $import_dir;
                }
                else
                {
                        return false;
                }
        }

        function getImportDirectory()
        {
                include_once "./classes/class.ilUtil.php";
                $import_dir = ilUtil::getDataDir()."/qpl_data/qpl_import";
                if(@is_dir($import_dir))
                {
                        return $import_dir;
                }
                else
                {
                        return false;
                }
        }

        function &getAllQuestions()
        {
                global $ilDB;

                $query = sprintf("SELECT question_id FROM qpl_questions WHERE obj_fi = %s AND original_id IS NULL",
                        $ilDB->quote($this->getId())
                );

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

                while ($row = $result->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        array_push($questions, $row["question_id"]);
                }
                return $questions;
        }

        function &getAllQuestionIds()
        {
                global $ilDB;

                $query = sprintf("SELECT question_id FROM qpl_questions WHERE ISNULL(original_id) AND obj_fi = %s AND complete = %s",
                        $ilDB->quote($this->getId()),
                        $ilDB->quote("1")
                );
                $query_result = $ilDB->query($query);
                $questions = array();
                if ($query_result->numRows())
                {
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                array_push($questions, $row["question_id"]);
                        }
                }
                return $questions;
        }

        function getImportMapping()
        {
                if (!is_array($this->import_mapping))
                {
                        return array();
                }
                else
                {
                        return $this->import_mapping;
                }
        }

        function to_xml($questions)
        {
                $xml = "";
                // export button was pressed
                if (count($questions) > 0)
                {
                        foreach ($questions as $key => $value)
                        {
                                $question =& $this->createQuestion("", $value);
                                $xml .= $question->object->to_xml();
                        }
                        if (count($questions) > 1)
                        {
                                $xml = preg_replace("/<\/questestinterop>\s*<.xml.*?>\s*<questestinterop>/", "", $xml);
                        }
                }
                $xml = preg_replace("/(<\?xml[^>]*?>)/", "\\1" . "<!DOCTYPE questestinterop SYSTEM \"ims_qtiasiv1p2p1.dtd\">", $xml);
                return $xml;
        }

        function _getQuestionCount($questionpool_id, $complete_questions_only = FALSE)
        {
                global $ilDB;
                $query = sprintf("SELECT COUNT(question_id) AS question_count FROM qpl_questions WHERE obj_fi = %s AND ISNULL(original_id)",
                        $ilDB->quote($questionpool_id . "")
                );
                if ($complete_questions_only)
                {
                        $query .= " AND complete = '1'";
                }
                $result = $ilDB->query($query);
                $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                return $row["question_count"];
        }

        function setOnline($a_online_status)
        {
                switch ($a_online_status)
                {
                        case 0:
                        case 1:
                                $this->online = $a_online_status;
                                break;
                        default:
                                $this->online = 0;
                                break;
                }
        }

        function getOnline()
        {
                if (strcmp($this->online, "") == 0) $this->online = "0";
                return $this->online;
        }

        function _lookupOnline($a_obj_id)
        {
                global $ilDB;

                $query = sprintf("SELECT online FROM qpl_questionpool WHERE obj_fi = %s",
                        $ilDB->quote($a_obj_id . "")
                );
                $result = $ilDB->query($query);
                if ($result->numRows() == 1)
                {
                        $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                        return $row["online"];
                }
                return 0;
        }

        function _hasEqualPoints($a_obj_id)
        {
                global $ilDB;
                $query = sprintf("SELECT count(DISTINCT points) AS equal_points FROM qpl_questions WHERE obj_fi = %s AND original_id IS NULL",
                        $ilDB->quote($a_obj_id . "")
                );
                $result = $ilDB->query($query);
                if ($result->numRows() == 1)
                {
                        $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                        if ($row["equal_points"] == 1)
                        {
                                return 1;
                        }
                        else
                        {
                                return 0;
                        }
                }
                return 0;
        }

        function pasteFromClipboard()
        {
                global $ilDB;

                if (array_key_exists("qpl_clipboard", $_SESSION))
                {
                        foreach ($_SESSION["qpl_clipboard"] as $question_object)
                        {
                                if (strcmp($question_object["action"], "move") == 0)
                                {
                                        $query = sprintf("SELECT obj_fi FROM qpl_questions WHERE question_id = %s",
                                                $ilDB->quote($question_object["question_id"])
                                        );
                                        $result = $ilDB->query($query);
                                        if ($result->numRows() == 1)
                                        {
                                                include_once "./content/classes/Pages/class.ilPageObject.php";
                                                $page = new ilPageObject("qpl", $question_object["question_id"]);
                                                $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                                                $source_questionpool = $row["obj_fi"];
                                                // change the questionpool id in the qpl_questions table
                                                $query = sprintf("UPDATE qpl_questions SET obj_fi = %s WHERE question_id = %s",
                                                        $ilDB->quote($this->getId() . ""),
                                                        $ilDB->quote($question_object["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // change page object of question and set the correct parent id
                                                $query = sprintf("UPDATE page_object SET parent_id = %s WHERE page_id = %s",
                                                        $ilDB->quote($this->getId() . ""),
                                                        $ilDB->quote($question_object["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // move question data to the new target directory
                                                $source_path = CLIENT_WEB_DIR . "/assessment/" . $source_questionpool . "/" . $question_object["question_id"] . "/";
                                                if (@is_dir($source_path))
                                                {
                                                        $target_path = CLIENT_WEB_DIR . "/assessment/" . $this->getId() . "/";
                                                        if (!@is_dir($target_path))
                                                        {
                                                                include_once "./classes/class.ilUtil.php";
                                                                ilUtil::makeDirParents($target_path);
                                                        }
                                                        @rename($source_path, $target_path . $question_object["question_id"]);
                                                }
                                                // update question count of source question pool
                                                ilObjQuestionPool::_updateQuestionCount($source_questionpool);
                                        }
                                }
                                else
                                {
                                        $this->copyQuestion($question_object["question_id"], $this->getId());
                                }
                        }
                }
                // update question count of question pool
                ilObjQuestionPool::_updateQuestionCount($this->getId());
                unset($_SESSION["qpl_clipboard"]);
        }

        function copyToClipboard($question_id)
        {
                if (!array_key_exists("qpl_clipboard", $_SESSION))
                {
                        $_SESSION["qpl_clipboard"] = array();
                }
                $_SESSION["qpl_clipboard"][$question_id] = array("question_id" => $question_id, "action" => "copy");
        }

        function moveToClipboard($question_id)
        {
                if (!array_key_exists("qpl_clipboard", $_SESSION))
                {
                        $_SESSION["qpl_clipboard"] = array();
                }
                $_SESSION["qpl_clipboard"][$question_id] = array("question_id" => $question_id, "action" => "move");
        }

        function _isWriteable($object_id, $user_id)
        {
                global $rbacsystem;
                global $ilDB;

                $result_array = array();
                $query = sprintf("SELECT object_data.*, object_data.obj_id, object_reference.ref_id FROM object_data, object_reference WHERE object_data.obj_id = object_reference.obj_id AND object_data.obj_id = %s",
                        $ilDB->quote($object_id . "")
                );
                $result = $ilDB->query($query);
                while ($row = $result->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        include_once "./classes/class.ilObject.php";
                        if ($rbacsystem->checkAccess("write", $row["ref_id"]) && (ilObject::_hasUntrashedReference($row["obj_id"])))
                        {
                                return true;
                        }
                }
                return false;
        }

        function &getQuestionDetails($question_ids)
        {
                global $ilDB;

                $result = array();
                $whereclause = join($question_ids, " OR qpl_questions.question_id = ");
                $whereclause = " AND (qpl_questions.question_id = " . $whereclause . ")";
                $query = "SELECT qpl_questions.*, qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE qpl_questions.question_type_fi = qpl_question_type.question_type_id$whereclause ORDER BY qpl_questions.title";
                $query_result = $ilDB->query($query);
                if ($query_result->numRows())
                {
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                array_push($result, $row);
                        }
                }
                return $result;
        }

        function &getDeleteableQuestionDetails($question_ids)
        {
                global $ilDB;

                $result = array();
                $whereclause = join($question_ids, " OR qpl_questions.question_id = ");
                $whereclause = " AND (qpl_questions.question_id = " . $whereclause . ")";
                $query = "SELECT qpl_questions.*, qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE qpl_questions.question_type_fi = qpl_question_type.question_type_id$whereclause ORDER BY qpl_questions.title";
                $query_result = $ilDB->query($query);
                if ($query_result->numRows())
                {
                        include_once "./assessment/classes/class.assQuestion.php";
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                if (!assQuestion::_isUsedInRandomTest($row["question_id"]))
                                {
                                        array_push($result, $row);
                                }
                                else
                                {
                                        // the question was used in a random test prior to ILIAS 3.7 so it was inserted
                                        // as a reference to the original question pool object and not as a copy. To allow
                                        // the deletion of the question pool object, a copy must be created and all database references
                                        // of the original question must changed with the reference of the copy

                                        // 1. Create a copy of the original question
                                        $question =& $this->createQuestion("", $row["question_id"]);
                                        $duplicate_id = $question->object->duplicate(true);
                                        if ($duplicate_id > 0)
                                        {
                                                // 2. replace the question id in the solutions
                                                $query = sprintf("UPDATE tst_solutions SET question_fi = %s WHERE question_fi = %s",
                                                        $ilDB->quote($duplicate_id),
                                                        $ilDB->quote($row["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // 3. replace the question id in the question list of random tests
                                                $query = sprintf("UPDATE tst_test_random_question SET question_fi = %s WHERE question_fi = %s",
                                                        $ilDB->quote($duplicate_id),
                                                        $ilDB->quote($row["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // 4. replace the question id in the test results
                                                $query = sprintf("UPDATE tst_test_result SET question_fi = %s WHERE question_fi = %s",
                                                        $ilDB->quote($duplicate_id),
                                                        $ilDB->quote($row["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // 5. replace the question id in the test&assessment log
                                                $query = sprintf("UPDATE ass_log SET question_fi = %s WHERE question_fi = %s",
                                                        $ilDB->quote($duplicate_id),
                                                        $ilDB->quote($row["question_id"])
                                                );
                                                $ilDB->query($query);

                                                // 6. The original question can be deleted, so add it to the list of questions
                                                array_push($result, $row);
                                        }
                                }
                        }
                }
                return $result;
        }

        function &getUsedQuestionDetails($question_ids)
        {
                global $ilDB;

                $result = array();
                $whereclause = join($question_ids, " OR qpl_questions.question_id = ");
                $whereclause = " AND (qpl_questions.question_id = " . $whereclause . ")";
                $query = "SELECT qpl_questions.*, qpl_question_type.type_tag FROM qpl_questions, qpl_question_type WHERE qpl_questions.question_type_fi = qpl_question_type.question_type_id$whereclause ORDER BY qpl_questions.title";
                $query_result = $ilDB->query($query);
                if ($query_result->numRows())
                {
                        include_once "./assessment/classes/class.assQuestion.php";
                        while ($row = $query_result->fetchRow(DB_FETCHMODE_ASSOC))
                        {
                                if (assQuestion::_isUsedInRandomTest($row["question_id"]))
                                {
                                        array_push($result, $row);
                                }
                        }
                }
                return $result;
        }

        function &_getAvailableQuestionpools($use_object_id = false)
        {
                global $rbacsystem;
                global $ilDB;

                $result_array = array();
                $query = "SELECT object_data.*, object_data.obj_id, object_reference.ref_id FROM object_data, object_reference WHERE object_data.obj_id = object_reference.obj_id AND object_data.type = 'qpl' ORDER BY object_data.title";
                $result = $ilDB->query($query);
                include_once "./classes/class.ilObject.php";
                while ($row = $result->fetchRow(DB_FETCHMODE_OBJECT))
                {
                        if ($rbacsystem->checkAccess("write", $row->ref_id) && (ilObject::_hasUntrashedReference($row->obj_id)))
                        {
                                if ($use_object_id)
                                {
                                        $result_array[$row->obj_id] = $row->title;
                                }
                                else
                                {
                                        $result_array[$row->ref_id] = $row->title;
                                }
                        }
                }
                return $result_array;
        }

        function &getQplQuestions()
        {
                global $ilDB;

                $questions = array();
                $query = sprintf("SELECT qpl_questions.question_id FROM qpl_questions WHERE ISNULL(qpl_questions.original_id) AND qpl_questions.obj_fi = %s",
                        $ilDB->quote($this->getId() . "")
                );
                $result = $ilDB->query($query);
                while ($row = $result->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        array_push($questions, $row["question_id"]);
                }
                return $questions;
        }
        function _clone($obj_id)
        {
                $original = new ilObjQuestionPool($obj_id, false);
                $original->loadFromDb();

                $newObj = new ilObjQuestionPool();
                $newObj->setType("qpl");
                $newObj->setTitle($original->getTitle() . " (".ilFormat::formatDate(ilFormat::unixtimestamp2datetime()).")");
                $newObj->setDescription($original->getDescription());
                $newObj->create(true);
                $newObj->createReference();
                $newObj->putInTree($_GET["ref_id"]);
                $newObj->setPermissions($_GET["ref_id"]);
                $newObj->setOnline($original->getOnline());
                $newObj->saveToDb();
                // clone the questions in the question pool
                $questions =& $original->getQplQuestions();
                foreach ($questions as $question_id)
                {
                        $newObj->copyQuestion($question_id, $newObj->getId());
                }

                // clone meta data
                include_once "./Services/MetaData/classes/class.ilMD.php";
                $md = new ilMD($original->getId(),0,$original->getType());
                $new_md =& $md->cloneMD($newObj->getId(),0,$newObj->getType());

                // update the metadata with the new title of the question pool
                $newObj->updateMetaData();

                return $newObj->getRefId();
        }

        function &getQuestionTypes()
        {
                global $ilDB;

                $query = "SELECT * FROM qpl_question_type ORDER BY question_type_id";
                $result = $ilDB->query($query);
                $types = array();
                while ($row = $result->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        $types[$this->lng->txt($row["type_tag"])] = $row;
                }
                ksort($types);
                return $types;
        }

        function &getQuestionList()
        {
                global $ilDB;

                $questions = array();
                $query = sprintf("SELECT qpl_questions.*, qpl_questions.TIMESTAMP+0 AS TIMESTAMP14, qpl_question_type.* FROM qpl_questions, qpl_question_type WHERE ISNULL(qpl_questions.original_id) AND qpl_questions.obj_fi = %s AND qpl_questions.question_type_fi = qpl_question_type.question_type_id",
                        $ilDB->quote($this->getId() . "")
                );
                $result = $ilDB->query($query);
                while ($row = $result->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        array_push($questions, $row);
                }
                return $questions;
        }

        function _updateQuestionCount($object_id)
        {
                global $ilDB;
                if ($ilDB->tableColumnExists("qpl_questionpool", "questioncount"))
                {
                        $query = sprintf("UPDATE qpl_questionpool SET questioncount = %s WHERE obj_fi = %s",
                                $ilDB->quote(ilObjQuestionPool::_getQuestionCount($object_id, TRUE)),
                                $ilDB->quote($object_id)
                        );
                        $result = $ilDB->query($query);
                }
        }
} // END class.ilObjQuestionPool
?>