<?php // $Id: exercise.php 12584 2010-09-06 12:12:10Z ffervaille $
/**
 * CLAROLINE
 *
 * @version 1.9 $Revision: 12584 $
 *
 * @copyright (c) 2001-2009 Universite catholique de Louvain (UCL)
 *
 * @license http://www.gnu.org/copyleft/gpl.html (GPL) GENERAL PUBLIC LICENSE
 *
 * @author Claro Team <cvs@claroline.net>
 * @author Dimitri Rambout <dimitri.rambout@uclouvain.be>
 *
 */

$tlabelReq = 'CLQWZ';

require '../inc/claro_init_global.inc.php';

if ( !claro_is_in_a_course() || !claro_is_course_allowed() ) claro_disp_auth_form(true);

claro_set_display_mode_available(true);

$is_allowedToEdit = claro_is_allowed_to_edit();
$is_allowedToTrack = claro_is_allowed_to_edit() && get_conf('is_trackingEnabled');

// tool libraries
include_once './lib/exercise.class.php';
include_once './lib/exercise.lib.php';

// claroline libraries
include_once get_path('incRepositorySys').'/lib/pager.lib.php';

/*
 * DB tables definition
 */

$tbl_cdb_names = get_module_course_tbl( array( 'qwz_exercise', 'qwz_question', 'qwz_rel_exercise_question' ), claro_get_current_course_id() );
$tbl_quiz_exercise = $tbl_cdb_names['qwz_exercise'];

$tbl_cdb_names = claro_sql_get_course_tbl();
$tbl_lp_module = $tbl_cdb_names['lp_module'];
$tbl_lp_asset = $tbl_cdb_names['lp_asset'];

// learning path 
// new module CLLP
$inLP = (claro_called_from() == 'CLLP')? true : false;

$_SESSION['inPathMode'] = false;

// init request vars
if ( isset($_REQUEST['cmd']) ) $cmd = $_REQUEST['cmd'];
else                           $cmd = null;

if( isset($_REQUEST['exId']) && is_numeric($_REQUEST['exId']) ) $exId = (int) $_REQUEST['exId'];
else                                                            $exId = null;

// init other vars
$maxFilledSpace = 100000000;
$courseDir = get_path('coursesRepositorySys') . claro_get_current_course_data('path');

$dialogBox = new DialogBox();

if( $is_allowedToEdit && !is_null($cmd) )
{
    //-- import
    if( $cmd == 'exImport')
    {
        require_once get_path('incRepositorySys') . '/lib/fileManage.lib.php';
        require_once get_path('incRepositorySys') . '/lib/fileDisplay.lib.php';
        require_once get_path('incRepositorySys') . '/lib/fileUpload.lib.php';
        require_once get_path('incRepositorySys') . '/lib/file.lib.php';

        require_once './export/exercise_import.inc.php';
        require_once './lib/question.class.php';
        require_once './export/qti2/qti2_classes.php';
        require_once get_path('incRepositorySys') . '/lib/backlog.class.php';

        if ( !isset($_FILES['uploadedExercise']['name']) )
        {
            $dialogBox->error( get_lang('Error : no file uploaded') );
        }
        else
        {
            $backlog = new Backlog();
            $importedExId = import_exercise($_FILES['uploadedExercise']['name'], $backlog);

            if( $importedExId )
            {
                $dialogBox->success( '<strong>' . get_lang('Import done') . '</strong>' );
            }
            else
            {
                $dialogBox->error( '<strong>' . get_lang('Import failed') . '</strong>' );
                $cmd = 'rqImport';
            }
            $dialogBox->info( $backlog->output() );
        }
    }

    if( $cmd == 'rqImport' )
    {
        require_once get_path('incRepositorySys') . '/lib/fileDisplay.lib.php';
        require_once get_path('incRepositorySys') . '/lib/fileUpload.lib.php';

        $dialogBox->form("\n"
        .            '<strong>' . get_lang('Import exercise') . '</strong><br />' . "\n"
        .            get_lang('Imported exercises must be an ims-qti zip file.') . '<br />' . "\n"
        .            '<form enctype="multipart/form-data" action="./exercise.php" method="post">' . "\n"
        .            '<input type="hidden" name="claroFormId" value="'.uniqid('').'">'."\n"
        .            '<input name="cmd" type="hidden" value="exImport" />' . "\n"
        .            '<input name="uploadedExercise" type="file" /><br />' . "\n"
        .            '<small>' . get_lang('Max file size') .  ' : ' . format_file_size( get_max_upload_size($maxFilledSpace,$courseDir) ) . '</small>' . "\n"
        .            '<p>' . "\n"
        .            '<input value="' . get_lang('Import exercise') . '" type="submit" /> ' . "\n"
        .            claro_html_button( './exercise.php', get_lang('Cancel'))
        .            '</p>' . "\n"
        .            '</form>' );
    }

    //-- export
    if( $cmd == 'rqExport' && $exId )
    {
      
      $exercise = new Exercise();
      
      if( ! $exercise->load( $exId ) )
      {
        $dialogBox->error( get_lang( 'Unable to load the exercise' ) );
      }
      else
      {
        $dialogBoxContent = "\n"
        .             '<strong>' . get_lang( 'Export exercise' ) . '</strong><br />' . "\n"
        .             get_lang( 'Select the type for your export :' ) . '<br />' . "\n"
        .             '<ul>' . "\n"
        ;
        
        if( get_conf('enableExerciseExportQTI') )
        {
          $dialogBoxContent .=  '<li>' . "\n"
          .                     '<img src="' . get_icon_url('export') . '" alt="'.get_lang('Export in IMS QTI').'" /> ' . "\n"
          .                     '<a href="' . htmlspecialchars( Url::Contextualize( 'exercise.php?cmd=exExport&exId=' . $exId ) ) . '">' . get_lang( 'Export in IMS QTI' ) . '</a>' . "\n"
          .                     '</li>' . "\n"
          ;
          
          if( $exercise->getShuffle() )
          {
            $dialogBoxContent .=  '<li>' . "\n"
            .                     '<img src="' . get_icon_url('export') . '" alt="'.get_lang('Export in IMS QTI (Shuffle)').'" /> ' . "\n"
            .                     '<a href="' . htmlspecialchars( Url::Contextualize( 'exercise.php?cmd=exExport&exId=' . $exId . '&shuffle=1' ) ) . '">' . get_lang( 'Export in IMS QTI (Shuffle)' ) . '</a>' . "\n"
            .                     '</li>' . "\n"
            ;
          }
        }
        
        $dialogBoxContent .=  '<li>' . "\n"
        .                     '<img src="' . get_icon_url('mime/pdf') . '" alt="'.get_lang('Export to PDF').'" /> ' . "\n"
        .                     '<a href="' . htmlspecialchars( Url::Contextualize( 'exercise.php?cmd=exExportPDF&exId=' . $exId ) ) . '">' . get_lang( 'Export to PDF' ) . '</a>' . "\n"
        .                     '</li>' . "\n"
        ;
        
        if( $exercise->getShuffle() )
        {
          $dialogBoxContent .=  '<li>' . "\n"
          .                     '<img src="' . get_icon_url('mime/pdf') . '" alt="'.get_lang('Export to PDF (Shuffle)').'" /> ' . "\n"
          .                     '<a href="' . htmlspecialchars( Url::Contextualize( 'exercise.php?cmd=exExportPDF&exId=' . $exId . '&shuffle=1' ) ) . '">' . get_lang( 'Export to PDF (Shuffle)' ) . '</a>' . "\n"
          .                     '</li>' . "\n"
          ;
        }
        
        $dialogBoxContent .=  '</ul>' . "\n"
        ;
        
        $dialogBox->question( $dialogBoxContent );
      }
    }
    
    if( $cmd == 'exExport' && get_conf('enableExerciseExportQTI') && $exId )
    {
        include_once './lib/question.class.php';

        require_once './export/qti2/qti2_export.php';
        require_once get_path('incRepositorySys') . '/lib/fileManage.lib.php';
        require_once get_path('incRepositorySys') . '/lib/file.lib.php';

        //find exercise informations

        $exercise= new Exercise();
        $exercise->load($exId);
        if( $exercise->getShuffle() && isset($_REQUEST['shuffle']) && $_REQUEST['shuffle'] == 1)
        {
          $questionList = $exercise->getRandomQuestionList();
        }
        else
        {
          $questionList = $exercise->getQuestionList();
        }

        $filePathList = array();
        
        //prepare xml file of each question
        $quRank = 0;
        foreach ($questionList as $question)
        {
            $quId = $question['id'];
            $questionObj = new Qti2Question();
            $questionObj->setRank( ++$quRank );
            $questionObj->load($quId);
            
            // contruction of XML flow
            $xml = $questionObj->export();
            // remove trailing slash
            if( substr($questionObj->questionDirSys, -1) == '/' )
            {
                $questionObj->questionDirSys = substr($questionObj->questionDirSys, 0, -1);
            }

            //save question xml file
            if( !file_exists($questionObj->questionDirSys) )
            {
                claro_mkdir($questionObj->questionDirSys,CLARO_FILE_PERMISSIONS);
            }

            if( $fp = @fopen($questionObj->questionDirSys."/question_".$quRank.".xml", 'w') )
            {
                fwrite($fp, $xml);
                fclose($fp);
            }
            else
            {
                // interrupt process
            }

            // list of dirs to add in archive
            $filePathList[] = $questionObj->questionDirSys;
        }

        if( !empty($filePathList) )
        {
            require_once get_path('incRepositorySys') . '/lib/thirdparty/pclzip/pclzip.lib.php';

            // build and send the zip
            // TODO use $courseDir ?

            if( sendZip($exercise->title, $filePathList, get_conf('coursesRepositorySys').claro_get_current_course_data('path') . '/exercise/' ) )
            {
                exit();
            }
            else
            {
                $dialogBox->error( get_lang("Unable to create zip file") );
            }
        }
    }

    //-- export pdf
    if( $cmd == 'exExportPDF' && $exId )
    {
        require_once( './lib/question.class.php' );
        
        $exercise= new Exercise();
        $exercise->load($exId);
        if( $exercise->getShuffle() && isset($_REQUEST['shuffle']) && $_REQUEST['shuffle'] == 1 )
        {
          $questionList = $exercise->getRandomQuestionList();
        }
        else
        {
          $questionList = $exercise->getQuestionList();
        }
        
        foreach( $questionList as $_id => $question )
        {
          $questionObj = new Question();
          $questionObj->setExerciseId($exId);
          
          if( $questionObj->load($question['id']) )
          {
            $questionList[ $_id ]['description'] = $questionObj->getDescription();
            $questionList[ $_id ]['attachment'] = $questionObj->getAttachment();
            if( !empty( $questionList[ $_id ]['attachment'] ) )
            {
              $questionList[ $_id ]['attachmentURL'] = get_conf('rootWeb') . 'courses/' . claro_get_current_course_id() . '/exercise/question_' . $questionObj->getId() . '/' . $questionObj->getAttachment();
            }
            
            switch( $questionObj->getType() )
            {
              case 'MCUA' :
              case 'MCMA' :
              {
                $questionList[ $_id ]['answers'] = $questionObj->answer->answerList;
              }
              break;
              case 'TF' :
              {
                $questionList[ $_id ]['answers'][0]['answer'] = get_lang('True');
                $questionList[ $_id ]['answers'][0]['feedback'] = $questionObj->answer->trueFeedback;
                $questionList[ $_id ]['answers'][1]['answer'] = get_lang('False');
                $questionList[ $_id ]['answers'][1]['feedback'] = $questionObj->answer->falseFeedback;
              }
              break;
              case 'FIB' :
              {
                $questionList[ $_id ]['answerText'] = $questionObj->answer->answerDecode( $questionObj->answer->answerText );
                $questionList[ $_id ]['answerList'] = $questionObj->answer->answerList;
                
                foreach( $questionList[ $_id ]['answerList'] as $i => $answer )
                {
                  $questionList[ $_id ]['answerList'][ $i ] = $questionObj->answer->answerDecode($questionObj->answer->addslashesEncodedBrackets($answer));
                }
                $questionList[ $_id ]['answerType'] = $questionObj->answer->type;
              }
              break;
              case 'MATCHING' :
              {
                $questionList[ $_id ]['leftList'] = $questionObj->answer->leftList;
                $questionList[ $_id ]['rightList'] = $questionObj->answer->rightList;
              }
              break;
            }
            
            $questionList[ $_id ]['type'] = $questionObj->getType();
          }
        }
        
        require_once( get_path('incRepositorySys') . '/lib/thirdparty/tcpdf/tcpdf.php' );
        
        // create new PDF document
        $pdf = new TCPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, 'UTF-8', false);
        
        $pdf->SetTitle( claro_utf8_encode( $exercise->getTitle() ) );
        $pdf->SetSubject( claro_utf8_encode( $exercise->getTitle() ) );
        
        //set margins
        $pdf->SetMargins(PDF_MARGIN_LEFT, PDF_MARGIN_TOP, PDF_MARGIN_RIGHT);
        $pdf->SetHeaderMargin(PDF_MARGIN_HEADER);
        $pdf->SetFooterMargin(PDF_MARGIN_FOOTER);
        
        //set auto page breaks
        $pdf->SetAutoPageBreak(TRUE, PDF_MARGIN_BOTTOM);
        
        //set image scale factor
        $pdf->setImageScale(PDF_IMAGE_SCALE_RATIO);
        
        $pdf->setPrintHeader(false);
        
        // add a page
        $pdf->AddPage();
        
        $htmlcontent = '<div style="font-size: xx-large; font-weight: bold;">' . htmlspecialchars( claro_utf8_encode( $exercise->getTitle() ) ) . '<div>' . "\n";
        $pdf->writeHTML( $htmlcontent, true, 0, true, 0);
        
        //change Img URL
        $exercise->setDescription( change_img_url_for_pdf( $exercise->getDescription() ) );
        //End change Img URL
        $htmlcontent = '<div style="font-size: normal; font-weight: normal;">'. $exercise->getDescription() .'</div><br /><br />' . "\n"
        ;
        $pdf->writeHTML( $htmlcontent, true, 0, true, 0);
        
        $i = 1;
        foreach( $questionList as $question )
        {
          $htmlcontent = '<p><table cellspacing="4">' . "\n"
          .   '<tbody>' . "\n"
          .   '<tr>' . "\n"
          .   '<th colspan="2" style="text-align: center; font-weight: bold; color: #693; background-color: #DEEECE;">' . get_lang('Question') . ' ' . $i . '</th>' . "\n"
          .   '</tr>' . "\n"
          // Question title
          .   '<tr>' . "\n"
          .   '<td colspan="2">' . htmlspecialchars( strip_tags( claro_utf8_encode( $question['title'], get_conf('charset') ) ) ) . '</td>' . "\n"
          .   '</tr>' . "\n"
          ;
          // Question description
          if( trim( htmlspecialchars( strip_tags( claro_utf8_encode( $question['description'], get_conf('charset') ) ) ) ) )
          {
            $htmlcontent .= '<tr>' . "\n"
            .   '<td colspan="2" style="font-size: x-small; font-style: italic;">' . claro_utf8_encode( change_img_url_for_pdf( $question['description'] ), get_conf('charset') ) .'</td>' . "\n"
            .   '</tr>' . "\n"
            ;
          }
          // Attachment
          if( ! empty( $question['attachment'] ) )
          {
            $extensionsList = array( 'jpg', 'jpeg', 'bmp', 'gif', 'png');
            
            $ext = strtolower( get_file_extension( $question['attachment'] ) );
            
            if( in_array( $ext, $extensionsList ) )
            {
              $htmlcontent .= '<tr>' . "\n"
              .   '<td colspan="2"><img src="' . $question['attachmentURL'] . '" /></td>' . "\n"
              .   '</tr>' . "\n"
              ;
            }
          }
          
          
          switch( $question['type'] )
          {
            case 'MCMA' :
            {
              foreach( $question['answers'] as $answer )
              {
                
                $htmlcontent .= '<tr>' . "\n"
                .   '<td style="background-color: #EEE; text-align: center; width: 30px;">[   ]</td>' . "\n"
                .   '<td style="background-color: #EEE; width: 475px;">' . htmlspecialchars( strip_tags( claro_utf8_encode( $answer['answer'], get_conf('charset') ) ) ) . '</td>' . "\n"
                .   '</tr>'
                ;
                
              }
            }
            break;
            case 'MCUA' :
            case 'TF' :
            {
              foreach( $question['answers'] as $answer )
              {
                
                $htmlcontent .= '<tr>' . "\n"
                .   '<td style="background-color: #EEE; text-align: center; width: 30px;">O</td>' . "\n"
                .   '<td style="background-color: #EEE; width: 475px;">' . htmlspecialchars( strip_tags( claro_utf8_encode( $answer['answer'], get_conf('charset') ) ) ) . '</td>' . "\n"
                .   '</tr>'
                ;
                
              }
            }
            break;
            case 'FIB' :
            {
              $answerCount = count( $question['answerList'] );
              $replacementList = array();
              switch( $question['answerType'] )
              {
                case 1 :
                {
                  for( $j = 0; $j < $answerCount; $j++ )
                  {
                      $replacementList[] = str_replace('$', '\$', ' [                  ] ');
                  }
                }
                break;
                default :
                {
                  $answers = '';
                  
                  foreach( $question['answerList'] as $answer )
                  {
                    if( $answers )
                    {
                      $answers .= "/";
                    }
                    $answers .= $answer;
                  }
                  
                  for( $j = 0; $j < $answerCount; $j++ )
                  {
                    $replacementList[] = str_replace('$', '\$', ' [ '. $answers .' ] ');
                  }
                }
              }
              
              
              $blankList = array();
              foreach( $question['answerList'] as $answer )
              {
                  // filter slashes as they are modifiers in preg expressions
                  $blankList[] = '/\['.preg_quote($answer,'/').'\]/';
              }
              
              $displayedAnswer = preg_replace( $blankList, $replacementList, claro_parse_user_text( $question['answerText'] ), 1 );
              
              $htmlcontent .= '<tr>' . "\n"
              .   '<td colspan="2" style="background-color: #EEE;">' . $displayedAnswer . '</td>' . "\n"
              .   '</tr>' . "\n"
              ;
            }
            break;
            case 'MATCHING' :
            {
              foreach( $question['leftList'] as $ql )
              {
                $ql['answer'] .= ' [';
                $_qr = '';
                foreach( $question['rightList'] as $qr)
                {
                  if( $_qr )
                  {
                    $_qr .= ' , ';
                  }
                  $_qr .= $qr['answer'];
                }
                $ql['answer'] .= $_qr;
                $ql['answer'] .= '] ';
                $htmlcontent .= '<tr>' . "\n"
                .   '<td colspan="2" style="background-color: #EEE;">' . htmlspecialchars( strip_tags( claro_utf8_encode( $ql['answer'], get_conf('charset') ) ) ) . '</td>' . "\n"
                .   '</tr>' . "\n"
                ;
              }
            }
            break;
          }
          
          $htmlcontent .= '</tbody>' . "\n"
          .   '</table></p>' . "\n"
          ;
          
          $pdf->writeHTML( $htmlcontent, true, 0, true, 0);
          
          $i++;
        }
        
        //Close and output PDF document
        $pdf->Output( 'exercise' . $exercise->getId() . '.pdf', 'D');
        
        exit();
    }
    //-- delete
    if( $cmd == 'exDel' && $exId )
    {
        $exercise = new Exercise();
        $exercise->load($exId);

        $exercise->delete();

        //notify manager that the exercise is deleted

        $eventNotifier->notifyCourseEvent("exercise_deleted",claro_get_current_course_id(), claro_get_current_tool_id(), $exId, claro_get_current_group_id(), "0");

    }

    //-- change visibility
    if( $cmd == 'exMkVis' && $exId )
    {
        Exercise::updateExerciseVisibility($exId,'VISIBLE');
        $eventNotifier->notifyCourseEvent("exercise_visible",claro_get_current_course_id(), claro_get_current_tool_id(), $exId, claro_get_current_group_id(), "0");
    }

    if( $cmd == 'exMkInvis' && $exId )
    {
        Exercise::updateExerciseVisibility($exId,'INVISIBLE');
        $eventNotifier->notifyCourseEvent("exercise_invisible",claro_get_current_course_id(), claro_get_current_tool_id(), $exId, claro_get_current_group_id(), "0");
    }
}

// Save question list
if( $cmd == 'exSaveQwz' )
{
    if( is_null( $exId) )
    {
        $dialogBox->error( get_lang('Error : unable to save the questions list') );
    }
    else
    {
        $exercise = new Exercise();
        if( ! $exercise->load( $exId ) )
        {
            $dialogBox->error( get_lang('Error: unable to load exercise') );
        }
        elseif( isset( $_SESSION['lastRandomQuestionList'] ) )
        {
            
            if ( !$exercise->saveRandomQuestionList( $_SESSION['_user']['userId'], $exercise->getId(), @unserialize($_SESSION['lastRandomQuestionList'])))
            {
                $dialogBox->error( get_lang('Error: unable to save this questions list') );
            }
            else
            {
                $dialogBox->success( get_lang('The list of questions has been saved') );
            }
            unset( $_SESSION['lastRandomQuestionList'] );
        }
        else
        {
            $dialogBox->error( get_lang('Error: no questions list in memory') );
        }
    }
}
/*
 * Get list
 */
// pager initialisation
if( !isset($_REQUEST['offset']) )    $offset = 0;
else                                $offset = $_REQUEST['offset'];

// prepare query
if($is_allowedToEdit)
{
    // we need to check if exercise is used as a module in a learning path
    // to display a more complete confirm message for delete aciton
    $sql = "SELECT E.`id`, E.`title`, E.`visibility`, M.`module_id`
              FROM `".$tbl_quiz_exercise."` AS E
             LEFT JOIN `".$tbl_lp_asset."` AS A
             ON (A.`path` = E.`id` OR A.`path` IS NULL)
             LEFT JOIN `".$tbl_lp_module."` AS M
             ON A.`module_id` = M.`module_id`
                 AND M.`contentType` = 'EXERCISE'
             ORDER BY `id`";
}
// only for students
else
{
  if (claro_is_user_authenticated())
  {
    $sql = "SELECT `id`, `title`
              FROM `".$tbl_quiz_exercise."`
              WHERE `visibility` = 'VISIBLE'
              ORDER BY `id`";
  }
  else // anonymous user
  {
    $sql = "SELECT `id`, `title`
              FROM `".$tbl_quiz_exercise."`
              WHERE `visibility` = 'VISIBLE'
                AND `anonymousAttempts` = 'ALLOWED'
              ORDER BY `id`";
  }
}

$myPager = new claro_sql_pager($sql, $offset, get_conf('exercisesPerPage',25));
$exerciseList = $myPager->get_result_list();


/*
 * Output
 */

$nameTools = get_lang('Exercises');

$noQUERY_STRING = true;
$out = '';

$out .= claro_html_tool_title($nameTools, $is_allowedToEdit ? 'help_exercise.php' : false);

//-- dialogBox
$out .= $dialogBox->render();

if( !$inLP )
{
    //-- claroCmd
    $cmd_menu = array();
    if(get_conf('is_trackingEnabled') && claro_is_user_authenticated())
    {
        $cmd_menu[] = '<a class="claroCmd" href="../tracking/userReport.php?userId='.claro_get_current_user_id().'"><img src="' . get_icon_url('statistics') . '" alt="" />'.get_lang('My results').'</a>';
    }
    
    if($is_allowedToEdit)
    {
        $cmd_menu[] = '<a class="claroCmd" href="admin/edit_exercise.php?cmd=rqEdit"><img src="' . get_icon_url('quiz_new') . '" alt="" />' . get_lang('New exercise').'</a>';
        $cmd_menu[] = '<a class="claroCmd" href="admin/question_pool.php"><img src="' . get_icon_url('question_pool') . '" alt="" />'.get_lang('Question pool').'</a>';
        $cmd_menu[] = '<a class="claroCmd" href="exercise.php?cmd=rqImport"><img src="' . get_icon_url('import') . '" alt="" />'.get_lang('Import exercise').'</a>';
    }
    
    $out .= '<p>' . claro_html_menu_horizontal($cmd_menu) . '</p>' . "\n";
    
    //-- pager
    $out .= $myPager->disp_pager_tool_bar($_SERVER['PHP_SELF']);
    
    //-- list
    
    $out .= '<table class="claroTable emphaseLine" border="0" align="center" cellpadding="2" cellspacing="2" width="100%">' . "\n\n"
    .     '<thead>' . "\n"
    .     '<tr class="headerX">' . "\n"
    .     '<th>' . get_lang('Exercise title') . '</th>' . "\n";
    
    $colspan = 1;
    
    if( $is_allowedToEdit )
    {
        $out .= '<th>' . get_lang('Modify') . '</th>' . "\n"
        .     '<th>' . get_lang('Delete') . '</th>' . "\n"
        .     '<th>' . get_lang('Visibility') . '</th>' . "\n";
        $colspan = 4;
    
        $out .= '<th>' . get_lang('Export') . '</th>' . "\n";
        $colspan++;
    
        if( $is_allowedToTrack )
        {
            $out .= '<th>' . get_lang('Statistics') . '</th>' . "\n";
            $colspan++;
        }
    }
    
    $out .= '</tr>' . "\n"
    .     '</thead>' . "\n\n"
    .     '<tbody>' . "\n\n";
    
    if( claro_is_user_authenticated() ) $notificationDate = $claro_notifier->get_notification_date(claro_get_current_user_id());
    
    if( !empty($exerciseList) )
    {
        foreach( $exerciseList as $anExercise )
        {
            if( $is_allowedToEdit && $anExercise['visibility'] == 'INVISIBLE' )
            {
                $invisibleClass = ' class="invisible"';
            }
            else
            {
                $invisibleClass = '';
            }
    
            //modify style if the file is recently added since last login
            if( claro_is_user_authenticated() && $claro_notifier->is_a_notified_ressource(claro_get_current_course_id(), $notificationDate, claro_get_current_user_id(), claro_get_current_group_id(), claro_get_current_tool_id(), $anExercise['id']) )
            {
                $appendToStyle = ' hot';
            }
            else
            {
                $appendToStyle = '';
            }
    
            $out .= '<tr'.$invisibleClass.'>' . "\n"
            .     '<td>'
            .     '<a href="exercise_submit.php?exId='.$anExercise['id'].'" class="item'.$appendToStyle.'">'
            .     '<img src="' . get_icon_url('quiz') . '" alt="" />'
            .     $anExercise['title']
            .     '</a>'
            .     '</td>' . "\n";
    
            if( $is_allowedToEdit )
            {
                $out .= '<td align="center">'
                .     '<a href="admin/edit_exercise.php?exId='.$anExercise['id'].'">'
                .     '<img src="' . get_icon_url('edit') . '" alt="'.get_lang('Modify').'" />'
                .     '</a>'
                .     '</td>' . "\n";
    
                $confirmString = '';
                if( !is_null($anExercise['module_id']) )
                {
                    $confirmString .= get_block('blockUsedInSeveralPath') . " ";
                }
                $confirmString .= get_lang('Are you sure you want to delete this exercise ?');
    
                $out .= '<td align="center">'
                .     '<a href="exercise.php?exId='.$anExercise['id'].'&amp;cmd=exDel" onclick="javascript:if(!confirm(\''.clean_str_for_javascript($confirmString).'\')) return false;">'
                .     '<img src="' . get_icon_url('delete') . '" alt="'.get_lang('Delete').'" />'
                .     '</a>'
                .     '</td>' . "\n";
    
                if( $anExercise['visibility'] == 'VISIBLE' )
                {
                    $out .= '<td align="center">'
                    .     '<a href="exercise.php?exId='.$anExercise['id'].'&amp;cmd=exMkInvis">'
                    .     '<img src="' . get_icon_url('visible') . '" alt="'.get_lang('Make invisible').'" />'
                    .     '</a>'
                    .     '</td>' . "\n";
                }
                else
                {
                    $out .= '<td align="center">'
                    .     '<a href="exercise.php?exId='.$anExercise['id'].'&amp;cmd=exMkVis">'
                    .     '<img src="' . get_icon_url('invisible') . '" alt="'.get_lang('Make visible').'" />'
                    .     '</a>'
                    .     '</td>' . "\n";
                }
    
                $out .= '<td align="center">'
                .     '<a href="exercise.php?exId='.$anExercise['id'].'&amp;cmd=rqExport">'
                .     '<img src="' . get_icon_url('export') . '" alt="'.get_lang('Export').'" />'
                .     '</a>'
                .     '</td>' . "\n";
    
                if( $is_allowedToTrack )
                {
                    $out .= '<td align="center">'
                    .     '<a href="track_exercises.php?exId='.$anExercise['id'].'&amp;src=ex">'
                    .     '<img src="' . get_icon_url('statistics') . '" alt="'.get_lang('Statistics').'" />'
                    .     '</a>'
                    .     '</td>' . "\n";
                }
            }
    
            $out .= '</tr>' . "\n\n";
        }
    }
    else
    {
        $out .= '<tr>' . "\n"
        .     '<td colspan="'.$colspan.'">' . get_lang('Empty') . '</td>' . "\n"
        .     '</tr>' . "\n\n";
    }
    
    $out .= '</tbody>' . "\n\n"
    .     '</table>' . "\n\n";
}
//-- pager
$out .= $myPager->disp_pager_tool_bar($_SERVER['PHP_SELF']);

$claroline->display->body->appendContent($out);

echo $claroline->display->render();

?>