<?php
/* For licensing terms, see /license.txt */
/**
*    This is the tracking library for Dokeos.
*    Include/require it in your code to use its functionality.
*
*    @package chamilo.library
*    @author Julio Montoya <gugli100@gmail.com> (Score average fixes)
*/

class Tracking {

    /**
     * Calculates the time spent on the platform by a user
     * @param int    User id
     * @param bool    True for calculating only time spent last week (optional)
     * @param int    Timestamp for filtering by Day (optional, default = 0)
     * @return timestamp $nb_seconds
     */
    public static function get_time_spent_on_the_platform($user_id, $last_week = false, $by_day = 0) {

        $tbl_track_login = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_LOGIN);

        $condition_time = '';
        if ($last_week) {
            $a_last_week = get_last_week();
            $fday_last_week = date('Y-m-d H:i:s',$a_last_week[0]);
            $lday_last_week = date('Y-m-d H:i:s',$a_last_week[6]);
            $condition_time = ' AND (login_date >= "'.$fday_last_week.'" AND logout_date <= "'.$lday_last_week.'") ';
        } else if (!empty($by_day)) {
            $fdate_time = date('Y-m-d',$by_day).' 00:00:00';
            $ldate_time = date('Y-m-d',$by_day).' 23:59:59';
            $condition_time = ' AND (login_date >= "'.$fdate_time.'" AND logout_date <= "'.$ldate_time.'" ) ';
        }

        $sql = 'SELECT login_date, logout_date FROM '.$tbl_track_login.'
                        WHERE login_user_id = '.intval($user_id).$condition_time;
        $rs = Database::query($sql);

        $nb_seconds = 0;

        $wrong_logout_dates = false;

        while ($a_connections = Database::fetch_array($rs)) {

            $s_login_date = $a_connections["login_date"];
            $s_logout_date = $a_connections["logout_date"];

            $i_timestamp_login_date = strtotime($s_login_date);
            $i_timestamp_logout_date = strtotime($s_logout_date);

            if($i_timestamp_logout_date>0)
            {
                $nb_seconds += ($i_timestamp_logout_date - $i_timestamp_login_date);
            }
            else
            { // there are wrong datas in db, then we can't give a wrong time
                $wrong_logout_dates = true;
            }

        }

        if($nb_seconds>0 || !$wrong_logout_dates)
        {
            return $nb_seconds;
        }
        else
        {
            return -1; //-1 means we have wrong datas in the db
        }
    }

    /**
     * Calculates the time spent on the course
     * @param     integer     User id
     * @param     string         Course code
     * @param     int            Session id (optional)
     * @return     timestamp     Time in seconds
     */
    public static function get_time_spent_on_the_course($user_id, $course_code, $session_id = 0) {
        // protect datas
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);

        $tbl_track_course = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);

        $condition_user = "";
        if (is_array($user_id)) {
            $condition_user = " AND user_id IN (".implode(',',$user_id).") ";
        } else {
            $user_id = intval($user_id);
            $condition_user = " AND user_id = '$user_id' ";
        }

        $sql = " SELECT SUM(UNIX_TIMESTAMP(logout_course_date)-UNIX_TIMESTAMP(login_course_date)) as nb_seconds
                FROM $tbl_track_course
                WHERE course_code='$course_code' AND session_id = '$session_id' $condition_user";

        $rs = Database::query($sql);
        $row = Database::fetch_array($rs);
        return $row['nb_seconds'];
    }

    /**
     * Get first connection date for a student
     * @param    int                  Student id
     * @return    string|bool     Date format long without day or false if there are no connections
     */
    public static function get_first_connection_date($student_id) {
        $tbl_track_login = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_LOGIN);
        $sql = 'SELECT login_date FROM ' . $tbl_track_login . '
                WHERE login_user_id = ' . intval($student_id) . '
                ORDER BY login_date ASC LIMIT 0,1';

        $rs = Database::query($sql);
        if(Database::num_rows($rs)>0) {
            if ($first_login_date = Database::result($rs, 0, 0)) {
                return api_convert_and_format_date($first_login_date, DATE_FORMAT_SHORT, date_default_timezone_get());
            }
        }
        return false;
    }


    /**
     * Get las connection date for a student
     * @param    int                  Student id
     * @param    bool            Show a warning message (optional)
     * @param    bool            True for returning results in timestamp (optional)
     * @return    string|int|bool Date format long without day, false if there are no connections or timestamp if parameter $return_timestamp is true
     */
    public static function get_last_connection_date($student_id, $warning_message = false, $return_timestamp = false) {
        $tbl_track_login = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_LOGIN);
        $sql = 'SELECT login_date FROM ' . $tbl_track_login . '
                        WHERE login_user_id = ' . intval($student_id) . '
                        ORDER BY login_date DESC LIMIT 0,1';

        $rs = Database::query($sql);
        if(Database::num_rows($rs)>0) {
            if ($last_login_date = Database::result($rs, 0, 0)) {                         
                $last_login_date = api_get_local_time($last_login_date);
                if ($return_timestamp) {
                    return api_strtotime($last_login_date,'UTC');
                } else {
                    if (!$warning_message) {
                        return api_format_date($last_login_date, DATE_FORMAT_SHORT);
                    } else {
                        $timestamp = api_strtotime($last_login_date,'UTC');
                        $currentTimestamp = time();

                        //If the last connection is > than 7 days, the text is red
                        //345600 = 7 days in seconds
                        if ($currentTimestamp - $timestamp > 604800)
                        {
                            return '<span style="color: #F00;">' . api_format_date($last_login_date, DATE_FORMAT_SHORT) . '</span>';
                        }
                        else
                        {
                            return api_format_date($last_login_date, DATE_FORMAT_SHORT);
                        }
                    }
                }
            }
        }
        return false;
    }

    /**
     * Get first user's connection date on the course
     * @param     int         User id
     * @param    string        Course code
     * @param    int            Session id (optional, default=0)
     * @return    string|bool    Date with format long without day or false if there is no date
     */
    public static function get_first_connection_date_on_the_course($student_id, $course_code, $session_id = 0, $convert_date = true) {

        // protect data
        $student_id  = intval($student_id);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);

        $tbl_track_login = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);
        $sql = 'SELECT login_course_date FROM '.$tbl_track_login.'
                        WHERE user_id = '.$student_id.'
                        AND course_code = "'.$course_code.'"
                        AND session_id = '.$session_id.'
                        ORDER BY login_course_date ASC LIMIT 0,1';
        $rs = Database::query($sql);
        if (Database::num_rows($rs)>0) {
            if ($first_login_date = Database::result($rs, 0, 0)) {
                if ($convert_date) {
                    return api_convert_and_format_date($first_login_date, DATE_FORMAT_SHORT, date_default_timezone_get());
                } else {
                    return $first_login_date;
                }
            }
        }
        return false;
    }

    /**
     * Get last user's connection date on the course
     * @param     int         User id
     * @param    string        Course code
     * @param    int            Session id (optional, default=0)
     * @return    string|bool    Date with format long without day or false if there is no date
     */
    public static function get_last_connection_date_on_the_course($student_id, $course_code, $session_id = 0, $convert_date = true) {

        // protect data
        $student_id  = intval($student_id);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);

        $tbl_track_e_course_access = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);
        $sql = 'SELECT login_course_date FROM '.$tbl_track_e_course_access.'
                        WHERE user_id = '.$student_id.'
                        AND course_code = "'.$course_code.'"
                        AND session_id = '.$session_id.'
                        ORDER BY login_course_date DESC LIMIT 0,1';

        $rs = Database::query($sql);
        if (Database::num_rows($rs)>0) {
            if ($last_login_date = Database::result($rs, 0, 0)) {
                $last_login_date = api_get_local_time($last_login_date, null, date_default_timezone_get());
                $timestamp = api_strtotime($last_login_date);
                $currentTimestamp = time();
                //If the last connection is > than 7 days, the text is red
                //345600 = 7 days in seconds
                if ($currentTimestamp - $timestamp > 604800) {
                    if ($convert_date) {
                        return '<span style="color: #F00;">' . api_format_date($last_login_date, DATE_FORMAT_SHORT) . (api_is_allowed_to_edit()?' <a href="'.api_get_path(REL_CODE_PATH).'announcements/announcements.php?action=add&remind_inactive='.$student_id.'" title="'.get_lang('RemindInactiveUser').'"><img align="middle" src="'.api_get_path(WEB_IMG_PATH).'messagebox_warning.gif" /></a>':'').'</span>';
                    } else {
                        return $last_login_date;
                    }
                } else {
                    if ($convert_date) {
                        return api_format_date($last_login_date, DATE_FORMAT_SHORT);
                    } else {
                        return $last_login_date;
                    }
                }
            }
        }
        return false;
    }

        /**
     * Get count connections on the course
         * @param   string  Course code
         * @param   int     Session id (optional)
     * @param   int     number of month (optional)
     * @return  int     count connections
     */
    public static function get_count_connections_on_the_course($course_code, $session_id = 0, $month = null) {

        // protect data
                $month_filter = '';
                if (isset($month)) {
                    $month = intval($month);
                    $month_filter = " AND MONTH(login_course_date)= $month ";
                }

        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);
                $count = 0;

        $tbl_track_e_course_access = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);
        $sql = "SELECT count(*) as count_connections FROM $tbl_track_e_course_access WHERE course_code = '$course_code' AND session_id = $session_id $month_filter";
        $rs = Database::query($sql);
        if (Database::num_rows($rs)>0) {
                    $row = Database::fetch_object($rs);
                    $count = $row->count_connections;
        }
        return $count;
    }

    /**
     * Get count courses per student
     * @param     int        Student id
     * @param    bool    Include sessions (optional)
     * @return  int        count courses
     */
    public static function count_course_per_student($user_id, $include_sessions = true) {

        $user_id = intval($user_id);
        $tbl_course_rel_user = Database :: get_main_table(TABLE_MAIN_COURSE_USER);
        $tbl_session_course_rel_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);

        $sql = 'SELECT DISTINCT course_code
                        FROM ' . $tbl_course_rel_user . '
                        WHERE user_id = ' . $user_id.' AND relation_type<>'.COURSE_RELATION_TYPE_RRHH;
        $rs = Database::query($sql);
        $nb_courses = Database::num_rows($rs);

        if ($include_sessions) {
            $sql = 'SELECT DISTINCT course_code
                            FROM ' . $tbl_session_course_rel_user . '
                            WHERE id_user = ' . $user_id;
            $rs = Database::query($sql);
            $nb_courses += Database::num_rows($rs);
        }

        return $nb_courses;
    }

    /**
     * This function gets the score average from all tests in a course by student
     * @param     int|array     Student(s) id
     * @param     string         Course code
     * @param    int            Exercise id (optional), filtered by exercise
     * @param    int            Session id (optional), if param $session_id is null it'll return results including sessions, 0 = session is not filtered
     * @return     string         value (number %) Which represents a round integer about the score average.
     */
    public static function get_avg_student_exercise_score($student_id, $course_code, $exercise_id = 0, $session_id = null) {

        // protect datas
        $course_code = Database::escape_string($course_code);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        if(!empty($a_course['db_name'])) {
            // table definition
            $tbl_course_quiz = Database::get_course_table(TABLE_QUIZ_TEST,$a_course['db_name']);
            $tbl_stats_exercise = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_EXERCICES);

            // Compose a filter based on optional exercise given
            $condition_quiz = "";
            if (!empty($exercise_id)) {
                $exercise_id = intval($exercise_id);
                $condition_quiz =" AND id = $exercise_id ";
            }

            // Compose a filter based on optional session id given
            $condition_session = "";
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = " AND session_id = $session_id ";
            }
            $sql = "SELECT count(id) FROM $tbl_course_quiz WHERE active <> -1 $condition_quiz ";
            $count_quiz = Database::fetch_row(Database::query($sql));

            $quiz_avg_total_score = 0;
            if (!empty($count_quiz[0]) && !empty($student_id)) {
                $condition_user = "";
                if (is_array($student_id)) {
                    $condition_user = " AND exe_user_id IN (".implode(',',$student_id).") ";
                } else {
                    $condition_user = " AND exe_user_id = '$student_id' ";
                }
                
                if (empty($exercise_id)) {
                    $sql = "SELECT id FROM $tbl_course_quiz WHERE active <> -1 $condition_quiz";
                    $exercises = Database::fetch_row(Database::query($sql));
                    $exercise_list = array();
                    $exercise_id = 0;
                    if (!empty($exercises)) {
                        foreach($exercises as $row) {
                    	   $exercise_list[] = $row['id'];
                        }
                        $exercise_id = implode("','",$exercise_list); 
                    }
                }
                
                $count_quiz = Database::fetch_row(Database::query($sql));
                
                $sql = "SELECT SUM(exe_result/exe_weighting*100) as avg_score, COUNT(*) as num_attempts
                        FROM $tbl_stats_exercise
                        WHERE exe_exo_id IN ('".$exercise_id."')
                        $condition_user
                        AND orig_lp_id = 0
                        AND exe_cours_id = '$course_code'
                        AND orig_lp_item_id = 0 $condition_session
                        ORDER BY exe_date DESC";                     
                $res = Database::query($sql);
                $row = Database::fetch_array($res);
                $quiz_avg_score = 0;
                if (!empty($row['avg_score'])) {
                    $quiz_avg_score = round($row['avg_score'],2);
                }
                if(!empty($row['num_attempts'])) {
                    $quiz_avg_score = round($quiz_avg_score / $row['num_attempts'], 2);
                }
                return $quiz_avg_score;
            }
        }
        return null;
    }


    /**
     * Get count student's exercise attempts
     * @param     int     Student id
     * @param    string    Course code
     * @param    int        Exercise id
     * @param    int        Learning path id (optional), for showing attempts inside a learning path $lp_id and $lp_item_id params are required.
     * @param    int        Learning path item id (optional), for showing attempts inside a learning path $lp_id and $lp_item_id params are required.
     * @return  int     count of attempts
     */
    public function count_student_exercise_attempts($student_id, $course_code, $exercise_id, $lp_id = 0, $lp_item_id = 0, $session_id = 0) {

        $course_code = Database::escape_string($course_code);
        $course_info = CourseManager :: get_course_information($course_code);
        $student_id  = intval($student_id);
        $exercise_id = intval($exercise_id);
        $session_id = intval($session_id);
        $count_attempts = 0;

        if (!empty($lp_id)) $lp_id = intval($lp_id);
        if (!empty($lp_item_id)) $lp_id = intval($lp_item_id);

        if (!empty($course_info['db_name'])) {
            $tbl_stats_exercices = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_EXERCICES, $course_info['db_name']);

            $sql = "SELECT COUNT(ex.exe_id) as essais FROM $tbl_stats_exercices AS ex
                    WHERE  ex.exe_cours_id = '$course_code'
                    AND ex.exe_exo_id = $exercise_id
                    AND orig_lp_id = $lp_id
                    AND orig_lp_item_id = $lp_item_id
                    AND exe_user_id= $student_id 
                    AND session_id = $session_id ";
            $rs = Database::query($sql);
            $row = Database::fetch_row($rs);
            $count_attempts = $row[0];
        }
        return $count_attempts;

    }

    /**
     * Returns the average student progress in the learning paths of the given
     * course.
     * @param   int/array    Student id(s)
     * @param   string        Course code
     * @param     array         Limit average to listed lp ids
     * @param    int            Session id (optional), if parameter $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @param    bool        Will return an array of the type: [sum_of_progresses, number] if it is set to true
     * @return double        Average progress of the user in this course
     */
    public static function get_avg_student_progress($student_id, $course_code, $lp_ids = array(), $session_id = null, $return_array = false) {

        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        if (!empty($a_course['db_name'])) {
            // table definition
            $tbl_course_lp_view = Database :: get_course_table(TABLE_LP_VIEW, $a_course['db_name']);
            $tbl_course_lp = Database :: get_course_table(TABLE_LP_MAIN, $a_course['db_name']);

            // Compose a filter based on optional learning paths list given
            $condition_lp = "";
            
            if (!empty($lp_ids)) {
                if (count($lp_ids) > 0) {
                    $condition_lp =" WHERE id IN(".implode(',',$lp_ids).") ";                    
                }
            }            
            $session_id = intval($session_id);
            $sql = "SELECT id FROM $tbl_course_lp lp $condition_lp";            
            $res_count_lp = Database::query($sql);
            // count the number of learning paths
            $lp_id = array();
            while ($row_lp = Database::fetch_array($res_count_lp,'ASSOC')) {                
                //$visibility = api_get_item_visibility($a_course, TOOL_LEARNPATH, $row_lp['id'], $session_id);                
              //  if ($visibility == 1) {
                    $lp_id[] = $row_lp['id'];
                //}
            }      
            $count_lp = count($lp_id);            
            
            $avg_progress = 0;
            //if there is at least one learning path and one student
            if ($count_lp>0 && !empty($student_id)) {
                $condition_user = "";
                if (is_array($student_id)) {
                    $$r = array_walk($student_id,'intval');
                    $condition_user = " lp_view.user_id IN (".implode(',',$student_id).") AND ";
                } else {
                    $student_id = intval($student_id);
                    $condition_user = " lp_view.user_id = '$student_id' AND ";
                }
                // Get last view for each student (in case of multi-attempt)
                // Also filter on LPs of this session
                $sql_maxes = "SELECT MAX(view_count), progress FROM $tbl_course_lp_view lp_view ".
                             "WHERE $condition_user session_id = $session_id AND lp_view.lp_id IN (".implode(',',$lp_id).") ".
                             "GROUP BY lp_id, user_id";                
                $res_maxes = Database::query($sql_maxes);
                $sum =  0;
                while ($row_maxes = Database::fetch_array($res_maxes)) {
                    $sum += $row_maxes[1];
                }                
                // average progress = total sum divided by the number of views
                // summed up.
                $number_items = count($lp_id);                
                if ($number_items == 0) {
                    return 0; //not necessary to return something else if there is no view
                }                
                if (!$return_array) {
                    $avg_progress = round($sum / $number_items, 1);
                    return $avg_progress;
                } else {
                    return array($sum, $number_items);
                }
            }
        }
        return null;
    }


    /**
     * This function gets:
     * 1. The score average from all SCORM Test items in all LP in a course-> All the answers / All the max scores.
     * 2. The score average from all Tests (quiz) in all LP in a course-> All the answers / All the max scores.
     * 3. And finally it will return the average between 1. and 2.
     * @todo improve performance, when loading 1500 users with 20 lps the script dies 
     * This function does not take the results of a Test out of a LP
     *
     * @param     mixed       Array of user ids or an user id
     * @param     string         Course code
     * @param     array         List of LP ids
     * @param     int            Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @param    bool        Returns an array of the type [sum_score, num_score] if set to true
     * @return     string         Value (number %) Which represents a round integer explain in got in 3.
     */
    public static function get_avg_student_score($student_id, $course_code, $lp_ids=array(), $session_id = null, $return_array = false) {

        // get global tables names
        $course_table               = Database :: get_main_table(TABLE_MAIN_COURSE);
        $course_user_table          = Database :: get_main_table(TABLE_MAIN_COURSE_USER);
        $table_session_course_user  = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_stats_exercices        = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_EXERCICES);
        $tbl_stats_attempts         = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_ATTEMPT);

        $course = CourseManager :: get_course_information($course_code);

        if (!empty($course['db_name'])) {
            
            // get course tables names
            $tbl_quiz_questions = Database :: get_course_table(TABLE_QUIZ_QUESTION,$course['db_name']);
            $lp_table           = Database :: get_course_table(TABLE_LP_MAIN,$course['db_name']);
            $lp_item_table      = Database :: get_course_table(TABLE_LP_ITEM,$course['db_name']);
            $lp_view_table      = Database :: get_course_table(TABLE_LP_VIEW,$course['db_name']);
            $lp_item_view_table = Database :: get_course_table(TABLE_LP_ITEM_VIEW,$course['db_name']);

            // Compose a filter based on optional learning paths list given

            $condition_lp = "";
            if(count($lp_ids) > 0) {
                $condition_lp =" AND id IN(".implode(',',$lp_ids).") ";
            }

            // Compose a filter based on optional session id
            $condition_session = "";
            if (isset($session_id)) {
                $session_id = intval($session_id);
                if (count($lp_ids) > 0) {
                    $condition_session = " AND session_id = $session_id ";
                } else {
                    $condition_session = " WHERE session_id = $session_id ";
                }
            }

            // Check the real number of LPs corresponding to the filter in the
            // database (and if no list was given, get them all)
            
            if (empty($session_id)) {
                $sql = "SELECT DISTINCT(id), use_max_score FROM $lp_table  WHERE session_id = 0 $condition_lp ";
            } else {
                $sql = "SELECT DISTINCT(id), use_max_score FROM $lp_table WHERE 1 $condition_lp ";
            }
            
            $res_row_lp = Database::query($sql);         
            $count_row_lp = Database::num_rows($res_row_lp);
            $lp_list = $use_max_score = array();
            
            while ($row_lp = Database::fetch_array($res_row_lp)) {
                $lp_list[]                     = $row_lp['id'];
                $use_max_score[$row_lp['id']]  = $row_lp['use_max_score'];
            }

            // Init local variables that will be used through the calculation
            $lp_scorm_score_total = 0;
            $lp_scorm_result_score_total = 0;

            $lp_scorm_loop=0;
            $lp_count = 0;
            $progress = 0;

            // prepare filter on users
            $condition_user1 = "";
            if (is_array($student_id)) {
                array_walk($student_id,'intval');
                $condition_user1 =" AND user_id IN (".implode(',',$student_id).") ";
            } else {
                $condition_user1 =" AND user_id = '$student_id' ";
            }
            
            if ($count_row_lp>0 && !empty($student_id)) {

                // Get all views through learning paths filter
                //@todo problem when a  course have more than 1500 users
                $sql = "SELECT MAX(view_count) as vc, id, progress, lp_id, user_id  FROM $lp_view_table ".
                        "WHERE lp_id IN (".implode(',',$lp_list).") $condition_user1 AND session_id= $session_id GROUP BY lp_id,user_id";
                //var_dump(          $sql              );                
                $rs_last_lp_view_id = Database::query($sql);
                $global_count_item = 0;
                $global_result = 0;

                if (Database::num_rows($rs_last_lp_view_id) > 0) {
                    // Cycle through each line of the results (grouped by lp_id, user_id)
                    while ($row_lp_view = Database::fetch_array($rs_last_lp_view_id)) {

                        $lp_view_id = $row_lp_view['id'];
                        $progress   = $row_lp_view['progress'];
                        $lp_id      = $row_lp_view['lp_id'];
                        $user_id    = $row_lp_view['user_id'];

                        // For the currently analysed view, get the score and
                        // max_score of each item if it is a sco or a TOOL_QUIZ
                        $sql_max_score = "SELECT lp_iv.score as score,lp_i.max_score, lp_iv.max_score as max_score_item_view, lp_i.path, lp_i.item_type, lp_i.id as iid".
                                  " FROM $lp_item_view_table as lp_iv INNER JOIN $lp_item_table as lp_i ".
                                  " ON lp_i.id = lp_iv.lp_item_id ".
                                  " AND (lp_i.item_type='sco' OR lp_i.item_type='".TOOL_QUIZ."') ".
                                  " WHERE lp_view_id='$lp_view_id'";
                        //echo $sql_max_score; echo '<br />';
                        
                        $res_max_score = Database::query($sql_max_score);
                        $count_total_loop = 0;
                        $num_rows_max_score = Database::num_rows($res_max_score);

                        // Go through each scorable element of this view
                        $count_items = 0;
                        $lp_partial_total = 0;
                        $score_of_scorm_calculate = 0;

                        while ($row_max_score = Database::fetch_array($res_max_score,'ASSOC')) {
                            $max_score              = $row_max_score['max_score'];  //Came from the original lp_item
                            $max_score_item_view    = $row_max_score['max_score_item_view']; //Came from the lp_item_view
                            $score                  = $row_max_score['score'];
                                                        
                            if ($row_max_score['item_type'] == 'sco') {
                                
                                // Check if it is sco (easier to get max_score)
                                //when there's no max score, we assume 100 as the max score, as the SCORM 1.2 says that the value should always be between 0 and 100.
                                if ($max_score == 0 || is_null($max_score) || $max_score == '') {                                
                                    //Chamilo style
                                    if ($use_max_score[$lp_id]) {
                                       $max_score = 100;
                                    } else {
                                        //Overwrites max score = 100 to use the one that came in the lp_item_view see BT#1613
                                        $max_score = $max_score_item_view;                                    
                                    }
                                }
                                
                                //Avoid division by zero errors
                                if (!empty($max_score)) {
                                    $lp_scorm_result_score_total += $score/$max_score;
                                    $lp_partial_total            += $score/$max_score;
                                    $current_value                = $score/$max_score;
                                }                            
                                    
                            } else {
                                // Case of a TOOL_QUIZ element
                                $item_id    = $row_max_score['iid'];
                                $item_path  = $row_max_score['path'];
                                // Get last attempt to this exercise  through
                                // the current lp for the current user
                                $sql_last_attempt = "SELECT exe_id FROM $tbl_stats_exercices ".
                                   " WHERE exe_exo_id = '$item_path' ".
                                   " AND exe_user_id = '$user_id' ".
                                   // " AND orig_lp_id = '$lp_id' ". //lp_id is already defined by the item_id
                                   " AND orig_lp_item_id = '$item_id' ".
                                   " AND exe_cours_id = '$course_code' AND session_id = $session_id".
                                   " ORDER BY exe_date DESC limit 1";
                                   
                                $result_last_attempt = Database::query($sql_last_attempt);
                                $num = Database :: num_rows($result_last_attempt);
                                if ($num > 0 ) {
                                    $id_last_attempt = Database :: result($result_last_attempt, 0, 0);

                                    // Within the last attempt number tracking, get the sum of
                                    // the max_scores of all questions that it was
                                    // made of (we need to make this call dynamic
                                    // because of random questions selection)
                                    $sql = "SELECT SUM(t.ponderation) as maxscore ".
                                       " FROM ( SELECT distinct question_id, marks, ponderation ".
                                       " FROM $tbl_stats_attempts AS at " .
                                       " INNER JOIN  $tbl_quiz_questions AS q ".
                                       " ON (q.id = at.question_id) ".
                                       " WHERE exe_id ='$id_last_attempt' ) AS t";
                                    $res_max_score_bis = Database::query($sql);
                                    $row_max_score_bis = Database :: fetch_array($res_max_score_bis);
                                    if (!empty($row_max_score_bis['maxscore'])) {
                                        $max_score = $row_max_score_bis['maxscore'];
                                    }                                    
                                    if (!empty($max_score)) {
                                        $lp_scorm_result_score_total += ($score/$max_score);
                                        $lp_partial_total  += ($score/$max_score);
                                        $current_value = $score/$max_score;
                                    }                                    
                                } else {
                                    //$lp_scorm_result_score_total += 0;
                                }
                            }
                            
                            // Normal way
                            if ($use_max_score[$lp_id]) {
                                $count_items++;
                            } else {
                                if ($max_score != '') {    
                                    $count_items++;
                                }
                            }
                                                                                
                        } //end while
                        $global_count_item +=$count_items;
                        //echo 'lp_view '.$lp_view_id.' - $count_items '.$count_items.' lp partiual '.$lp_partial_total.' <br />';

                        $score_of_scorm_calculate += $count_items?(($lp_partial_total/$count_items)*100):0;
                       // var_dump($score_of_scorm_calculate);
                        $global_result += $score_of_scorm_calculate;                        
                    } // end while
                    /*echo '<br>$lp_scorm_result_score_total:'.($global_result); echo '<br>';
                    echo ("lp score :".($score_of_scorm_calculate));
                    echo '<br>';*/ 
                }

                $lp_with_quiz = 0;
                $total_lp = 0;
                //var_dump($lp_list);
                foreach($lp_list as $lp_id) {
                    //check if LP have a score
                    $sql = "SELECT count(id) as count FROM $lp_item_table
                            WHERE item_type = 'quiz' AND lp_id = ".$lp_id." ";
                    $result_have_quiz = Database::query($sql);

                    if (Database::num_rows($result_have_quiz) > 0 ) {
                        $row = Database::fetch_array($result_have_quiz,'ASSOC');
                        if (is_numeric($row['count']) && $row['count'] != 0) {
                            $lp_with_quiz ++;
                        }
                    }
                    $total_lp ++;
                }
                //var_dump($lp_with_quiz);
                if ($lp_with_quiz != 0 ) {
                    if (!$return_array) {
                        //var_dump($global_result,$lp_with_quiz );
                        $score_of_scorm_calculate = round(($global_result/$lp_with_quiz),2);                        
                        return $score_of_scorm_calculate;
                    } else {
                        return array($global_result, $lp_with_quiz);
                    }
                } else {
                    return '-';
                }

            }
        }
        return null;
    }


    /**
     * This function gets time spent in learning path for a student inside a course
     * @param     int|array    Student id(s)
     * @param     string         Course code
     * @param     array         Limit average to listed lp ids
     * @param     int            Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @return     int         Total time
     */
    public static function get_time_spent_in_lp($student_id, $course_code, $lp_ids = array(), $session_id = null) {

        $course = CourseManager :: get_course_information($course_code);
        $student_id = intval($student_id);
        $total_time = 0;

        if (!empty($course['db_name'])) {

            $lp_table   = Database :: get_course_table(TABLE_LP_MAIN, $course['db_name']);
            $t_lpv         = Database :: get_course_table(TABLE_LP_VIEW, $course['db_name']);
            $t_lpiv     = Database :: get_course_table(TABLE_LP_ITEM_VIEW, $course['db_name']);

            // Compose a filter based on optional learning paths list given
            $condition_lp = "";
            if(count($lp_ids) > 0) {
                $condition_lp =" WHERE id IN(".implode(',',$lp_ids).") ";
            }

            // Compose a filter based on optional session id
            $condition_session = "";
            $session_id = intval($session_id);
            
            if (isset($session_id)) {                
                if (count($lp_ids) > 0) {
                    $condition_session = " AND session_id = $session_id ";
                } else {
                    $condition_session = " WHERE session_id = $session_id ";
                }
            }

            // Check the real number of LPs corresponding to the filter in the
            // database (and if no list was given, get them all)
            //$res_row_lp = Database::query("SELECT DISTINCT(id) FROM $lp_table $condition_lp $condition_session");
            $res_row_lp = Database::query("SELECT DISTINCT(id) FROM $lp_table $condition_lp");
            $count_row_lp = Database::num_rows($res_row_lp);

            // calculates time
            if ($count_row_lp > 0) {
                while ($row_lp = Database::fetch_array($res_row_lp)) {
                    $lp_id = intval($row_lp['id']);
                    $sql = 'SELECT SUM(total_time)
                            FROM '.$t_lpiv.' AS item_view
                            INNER JOIN '.$t_lpv.' AS view
                                ON item_view.lp_view_id = view.id
                                AND view.lp_id = '.$lp_id.'
                                AND view.user_id = '.$student_id.' AND session_id = '.$session_id;
                        
                        $rs = Database::query($sql);
                        if (Database :: num_rows($rs) > 0) {
                            $total_time += Database :: result($rs, 0, 0);
                        }
                }
            }
        }
        return $total_time;
    }

    /**
     * This function gets last connection time to one learning path
     * @param     int|array    Student id(s)
     * @param     string         Course code
     * @param     int         Learning path id
     * @return     int         Total time
     */
    public static function get_last_connection_time_in_lp($student_id, $course_code, $lp_id, $session_id=0) {

        $course = CourseManager :: get_course_information($course_code);
        $student_id = intval($student_id);
        $lp_id = intval($lp_id);
        $last_time = 0;
        $session_id = intval($session_id);

        if (!empty($course['db_name'])) {

            $lp_table    = Database :: get_course_table(TABLE_LP_MAIN, $course['db_name']);
            $t_lpv       = Database :: get_course_table(TABLE_LP_VIEW, $course['db_name']);
            $t_lpiv      = Database :: get_course_table(TABLE_LP_ITEM_VIEW, $course['db_name']);

            // Check the real number of LPs corresponding to the filter in the
            // database (and if no list was given, get them all)
            $res_row_lp = Database::query("SELECT id FROM $lp_table WHERE id = $lp_id ");
            $count_row_lp = Database::num_rows($res_row_lp);

            // calculates last connection time
            if ($count_row_lp > 0) {
                $sql = 'SELECT MAX(start_time)
                        FROM ' . $t_lpiv . ' AS item_view
                        INNER JOIN ' . $t_lpv . ' AS view
                            ON item_view.lp_view_id = view.id
                            AND view.lp_id = '.$lp_id.'
                            AND view.user_id = '.$student_id.' 
                            AND view.session_id = '.$session_id;
                $rs = Database::query($sql);
                if (Database :: num_rows($rs) > 0) {
                    $last_time = Database :: result($rs, 0, 0);
                }
            }
        }
        return $last_time;
    }

    /**
     * gets the list of students followed by coach
     * @param     int     Coach id
     * @return     array     List of students
     */
    public static function get_student_followed_by_coach($coach_id) {
        $coach_id = intval($coach_id);

        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
        $tbl_session_user = Database :: get_main_table(TABLE_MAIN_SESSION_USER);
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);

        $a_students = array ();

        // At first, courses where $coach_id is coach of the course //
        $sql = 'SELECT id_session, course_code FROM ' . $tbl_session_course_user . ' WHERE id_user=' . $coach_id.' AND status=2';

        global $_configuration;
        if ($_configuration['multiple_access_urls']) {
            $tbl_session_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_SESSION);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1) {
                $sql = 'SELECT scu.id_session, scu.course_code
                        FROM ' . $tbl_session_course_user . ' scu INNER JOIN '.$tbl_session_rel_access_url.'  sru
                        ON (scu.id_session=sru.session_id)
                        WHERE scu.id_user=' . $coach_id.' AND scu.status=2 AND sru.access_url_id = '.$access_url_id;
            }
        }

        $result = Database::query($sql);

        while ($a_courses = Database::fetch_array($result)) {

            $course_code = $a_courses["course_code"];
            $id_session = $a_courses["id_session"];

            $sql = "SELECT distinct    srcru.id_user
                                FROM $tbl_session_course_user AS srcru, $tbl_session_user sru
                                WHERE srcru.id_user = sru.id_user AND sru.relation_type<>".SESSION_RELATION_TYPE_RRHH." AND srcru.id_session = sru.id_session AND srcru.course_code='$course_code' AND srcru.id_session='$id_session'";

            $rs = Database::query($sql);

            while ($row = Database::fetch_array($rs)) {
                $a_students[$row['id_user']] = $row['id_user'];
            }
        }

        // Then, courses where $coach_id is coach of the session    //

        $sql = 'SELECT session_course_user.id_user
                        FROM ' . $tbl_session_course_user . ' as session_course_user
                        INNER JOIN     '.$tbl_session_user.' sru ON session_course_user.id_user = sru.id_user AND session_course_user.id_session = sru.id_session
                        INNER JOIN ' . $tbl_session_course . ' as session_course
                            ON session_course.course_code = session_course_user.course_code
                            AND session_course_user.id_session = session_course.id_session
                        INNER JOIN ' . $tbl_session . ' as session
                            ON session.id = session_course.id_session
                            AND session.id_coach = ' . $coach_id;
        if ($_configuration['multiple_access_urls']) {
            $tbl_session_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_SESSION);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1){
                $sql = 'SELECT session_course_user.id_user
                FROM ' . $tbl_session_course_user . ' as session_course_user
                INNER JOIN     '.$tbl_session_user.' sru ON session_course_user.id_user = sru.id_user AND session_course_user.id_session = sru.id_session
                INNER JOIN ' . $tbl_session_course . ' as session_course
                    ON session_course.course_code = session_course_user.course_code
                    AND session_course_user.id_session = session_course.id_session
                INNER JOIN ' . $tbl_session . ' as session
                    ON session.id = session_course.id_session
                    AND session.id_coach = ' . $coach_id.'
                INNER JOIN '.$tbl_session_rel_access_url.'  session_rel_url
                    ON session.id = session_rel_url.session_id WHERE access_url_id = '.$access_url_id;
            }
        }

        $result = Database::query($sql);

        while ($row = Database::fetch_array($result)) {
            $a_students[$row['id_user']] = $row['id_user'];
        }
        return $a_students;
    }

    /**
     * Get student followed by a coach inside a session
     * @param    int        Session id
     * @param    int        Coach id
     * @return     array    students list
     */
    public static function get_student_followed_by_coach_in_a_session($id_session, $coach_id) {

        $coach_id = intval($coach_id);

        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);

        $a_students = array ();

        //////////////////////////////////////////////////////////////
        // At first, courses where $coach_id is coach of the course //
        //////////////////////////////////////////////////////////////
        $sql = 'SELECT course_code FROM ' . $tbl_session_course_user . ' WHERE id_session="' . $id_session . '" AND id_user=' . $coach_id.' AND status=2';

        $result = Database::query($sql);

        while ($a_courses = Database::fetch_array($result)) {
            $course_code = $a_courses["course_code"];

            $sql = "SELECT distinct    srcru.id_user
                                FROM $tbl_session_course_user AS srcru
                                WHERE course_code='$course_code' and id_session = '" . $id_session . "'";

            $rs = Database::query($sql);

            while ($row = Database::fetch_array($rs)) {
                $a_students[$row['id_user']] = $row['id_user'];
            }
        }

        //////////////////////////////////////////////////////////////
        // Then, courses where $coach_id is coach of the session    //
        //////////////////////////////////////////////////////////////

        $dsl_session_coach = 'SELECT id_coach FROM ' . $tbl_session . ' WHERE id="' . $id_session . '" AND id_coach="' . $coach_id . '"';
        $result = Database::query($dsl_session_coach);
        //He is the session_coach so we select all the users in the session
        if (Database::num_rows($result) > 0) {
            $sql = 'SELECT DISTINCT srcru.id_user FROM ' . $tbl_session_course_user . ' AS srcru WHERE id_session="' . $id_session . '"';
            $result = Database::query($sql);
            while ($row = Database::fetch_array($result)) {
                $a_students[$row['id_user']] = $row['id_user'];
            }
        }
        return $a_students;
    }

    /**
     * Check if a coach is allowed to follow a student
     * @param    int        Coach id
     * @param    int        Student id
     * @return    bool
     */
    public static function is_allowed_to_coach_student($coach_id, $student_id) {
        $coach_id = intval($coach_id);
        $student_id = intval($student_id);

        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);

        //////////////////////////////////////////////////////////////
        // At first, courses where $coach_id is coach of the course //
        //////////////////////////////////////////////////////////////
        /*$sql = 'SELECT 1
                        FROM ' . $tbl_session_course_user . ' AS session_course_user
                        INNER JOIN ' . $tbl_session_course . ' AS session_course
                            ON session_course.course_code = session_course_user.course_code
                            AND id_coach=' . $coach_id . '
                        WHERE id_user=' . $student_id;*/

        $sql = 'SELECT 1 FROM ' . $tbl_session_course_user . ' WHERE id_user=' . $coach_id .' AND status=2';

        $result = Database::query($sql);
        if (Database::num_rows($result) > 0) {
            return true;
        }

        //////////////////////////////////////////////////////////////
        // Then, courses where $coach_id is coach of the session    //
        //////////////////////////////////////////////////////////////

        $sql = 'SELECT session_course_user.id_user
                        FROM ' . $tbl_session_course_user . ' as session_course_user
                        INNER JOIN ' . $tbl_session_course . ' as session_course
                            ON session_course.course_code = session_course_user.course_code
                        INNER JOIN ' . $tbl_session . ' as session
                            ON session.id = session_course.id_session
                            AND session.id_coach = ' . $coach_id . '
                        WHERE id_user = ' . $student_id;
        $result = Database::query($sql);
        if (Database::num_rows($result) > 0) {
            return true;
        }

        return false;

    }


    /**
     * Get courses followed by coach
     * @param     int        Coach id
     * @param    int        Session id (optional)
     * @return    array    Courses list
     */
    public static function get_courses_followed_by_coach($coach_id, $id_session = '')
    {

        $coach_id = intval($coach_id);
        if (!empty ($id_session))
            $id_session = intval($id_session);

        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);
        $tbl_course = Database :: get_main_table(TABLE_MAIN_COURSE);

        //////////////////////////////////////////////////////////////
        // At first, courses where $coach_id is coach of the course //
        //////////////////////////////////////////////////////////////
        $sql = 'SELECT DISTINCT course_code FROM ' . $tbl_session_course_user . ' WHERE id_user=' . $coach_id.' AND status=2';

        global $_configuration;
        if ($_configuration['multiple_access_urls']) {
            $tbl_course_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1){
                $sql = 'SELECT DISTINCT scu.course_code FROM ' . $tbl_session_course_user . ' scu INNER JOIN '.$tbl_course_rel_access_url.' cru
                        ON (scu.course_code = cru.course_code)
                        WHERE scu.id_user=' . $coach_id.' AND scu.status=2 AND cru.access_url_id = '.$access_url_id;
            }
        }

        if (!empty ($id_session))
            $sql .= ' AND id_session=' . $id_session;
        $result = Database::query($sql);
        while ($row = Database::fetch_array($result)) {
            $a_courses[$row['course_code']] = $row['course_code'];
        }

        //////////////////////////////////////////////////////////////
        // Then, courses where $coach_id is coach of the session    //
        //////////////////////////////////////////////////////////////
        $sql = 'SELECT DISTINCT session_course.course_code
                        FROM ' . $tbl_session_course . ' as session_course
                        INNER JOIN ' . $tbl_session . ' as session
                            ON session.id = session_course.id_session
                            AND session.id_coach = ' . $coach_id . '
                        INNER JOIN ' . $tbl_course . ' as course
                            ON course.code = session_course.course_code';

        if ($_configuration['multiple_access_urls']) {
            $tbl_course_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1){
                $sql = 'SELECT DISTINCT session_course.course_code
                        FROM ' . $tbl_session_course . ' as session_course
                        INNER JOIN ' . $tbl_session . ' as session
                            ON session.id = session_course.id_session
                            AND session.id_coach = ' . $coach_id . '
                        INNER JOIN ' . $tbl_course . ' as course
                            ON course.code = session_course.course_code
                         INNER JOIN '.$tbl_course_rel_access_url.' course_rel_url
                        ON (session_course.course_code = course_rel_url.course_code)';
            }
        }

        if (!empty ($id_session)) {
            $sql .= ' WHERE session_course.id_session=' . $id_session;
            if ($_configuration['multiple_access_urls'])
                $sql .=  ' AND access_url_id = '.$access_url_id;
        }  else {
            if ($_configuration['multiple_access_urls'])
                $sql .=  ' WHERE access_url_id = '.$access_url_id;
        }

        $result = Database::query($sql);

        while ($row = Database::fetch_array($result)) {
            $a_courses[$row['course_code']] = $row['course_code'];
        }

        return $a_courses;
    }

    /**
     * Get sessions coached by user
     * @param    int        Coach id
     * @return    array    Sessions list
     */
    public static function get_sessions_coached_by_user($coach_id) {
        // table definition
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);

        // protect datas
        $coach_id = intval($coach_id);

        // session where we are general coach
        $sql = 'SELECT DISTINCT id, name, date_start, date_end
                        FROM ' . $tbl_session . '
                        WHERE id_coach=' . $coach_id;

        global $_configuration;
        if ($_configuration['multiple_access_urls']) {
            $tbl_session_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_SESSION);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1){
                $sql = 'SELECT DISTINCT id, name, date_start, date_end
                        FROM ' . $tbl_session . ' session INNER JOIN '.$tbl_session_rel_access_url.' session_rel_url
                        ON (session.id = session_rel_url.session_id)
                        WHERE id_coach=' . $coach_id.' AND access_url_id = '.$access_url_id;
            }
        }

        $rs = Database::query($sql);

        while ($row = Database::fetch_array($rs))
        {
            $a_sessions[$row["id"]] = $row;
        }

        // session where we are coach of a course
        $sql = 'SELECT DISTINCT session.id, session.name, session.date_start, session.date_end
                        FROM ' . $tbl_session . ' as session
                        INNER JOIN ' . $tbl_session_course_user . ' as session_course_user
                            ON session.id = session_course_user.id_session
                            AND session_course_user.id_user=' . $coach_id.' AND session_course_user.status=2';

        global $_configuration;
        if ($_configuration['multiple_access_urls']) {
            $tbl_session_rel_access_url= Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_SESSION);
            $access_url_id = api_get_current_access_url_id();
            if ($access_url_id != -1){
                $sql = 'SELECT DISTINCT session.id, session.name, session.date_start, session.date_end
                        FROM ' . $tbl_session . ' as session
                        INNER JOIN ' . $tbl_session_course_user . ' as session_course_user
                            ON session.id = session_course_user.id_session AND session_course_user.id_user=' . $coach_id.' AND session_course_user.status=2
                        INNER JOIN '.$tbl_session_rel_access_url.' session_rel_url
                        ON (session.id = session_rel_url.session_id)
                        WHERE access_url_id = '.$access_url_id;
            }
        }

        $rs = Database::query($sql);

        while ($row = Database::fetch_array($rs))
        {
            $a_sessions[$row["id"]] = $row;
        }

        if (is_array($a_sessions)) {
            foreach ($a_sessions as & $session) {
                if ($session['date_start'] == '0000-00-00') {
                    $session['status'] = get_lang('SessionActive');
                }
                else {
                    $date_start = explode('-', $session['date_start']);
                    $time_start = mktime(0, 0, 0, $date_start[1], $date_start[2], $date_start[0]);
                    $date_end = explode('-', $session['date_end']);
                    $time_end = mktime(0, 0, 0, $date_end[1], $date_end[2], $date_end[0]);
                    if ($time_start < time() && time() < $time_end) {
                        $session['status'] = get_lang('SessionActive');
                    }
                    else{
                        if (time() < $time_start) {
                            $session['status'] = get_lang('SessionFuture');
                        }
                        else{
                            if (time() > $time_end) {
                                $session['status'] = get_lang('SessionPast');
                            }
                        }
                    }
                }
            }
        }
        return $a_sessions;

    }

    /**
     * Get courses list from a session
     * @param    int        Session id
     * @return    array    Courses list
     */
    public static function get_courses_list_from_session($session_id) {
        //protect datas
        $session_id = intval($session_id);

        // table definition
        $tbl_session = Database :: get_main_table(TABLE_MAIN_SESSION);
        $tbl_session_course = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);

        $sql = 'SELECT DISTINCT course_code
                        FROM ' . $tbl_session_course . '
                        WHERE id_session=' . $session_id;

        $rs = Database::query($sql);
        $a_courses = array ();
        while ($row = Database::fetch_array($rs)) {
            $a_courses[$row['course_code']] = $row;
        }
        return $a_courses;
    }


    /**
     * Count assignments per student
     * @param    int|array   Student id(s)
     * @param    string        Course code
     * @param    int            Session id (optional), if param $session_id is null(default) return count of assignments including sessions, 0 = session is not filtered
     * @return    int            Count of assignments
     */
    public static function count_student_assignments($student_id, $course_code, $session_id = null) {
        require_once (api_get_path(LIBRARY_PATH) . 'course.lib.php');

        // protect datas
        $course_code = Database::escape_string($course_code);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        if (!empty($a_course['db_name'])) {
            // table definition
            $tbl_item_property          = Database :: get_course_table(TABLE_ITEM_PROPERTY, $a_course['db_name']);
            $tbl_student_publication = Database :: get_course_table(TABLE_STUDENT_PUBLICATION, $a_course['db_name']);

            $condition_user = "";
            if (is_array($student_id)) {
                $condition_user = " AND ip.insert_user_id IN (".implode(',',$student_id).") ";
            } else {
                $condition_user = " AND ip.insert_user_id = '$student_id' ";
            }

            $condition_session = "";
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = " AND pub.session_id = $session_id ";
            }

            $sql = "SELECT count(ip.tool) FROM $tbl_item_property ip INNER JOIN $tbl_student_publication pub ON ip.ref = pub.id WHERE ip.tool='work' $condition_user $condition_session ";
            $rs = Database::query($sql);
            $row = Database::fetch_row($rs);
            return $row[0];
        }
        return null;
    }


    /**
     * Count messages per student inside forum tool
     * @param    int        Student id
     * @param    string    Course code
     * @param    int        Session id (optional), if param $session_id is null(default) return count of messages including sessions, 0 = session is not filtered
     * @return    int        Count of messages
     */
    function count_student_messages($student_id, $course_code, $session_id = null) {
        require_once (api_get_path(LIBRARY_PATH) . 'course.lib.php');

        // protect datas
        $student_id = intval($student_id);
        $course_code = addslashes($course_code);

        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);

        if(!empty($a_course['db_name']))
        {
            // table definition
            $tbl_forum_post = Database :: get_course_table(TABLE_FORUM_POST, $a_course['db_name']);
            $tbl_forum         = Database :: get_course_table(TABLE_FORUM, $a_course['db_name']);

            $condition_user = "";
            if (is_array($student_id)) {
                $condition_user = " WHERE post.poster_id IN (".implode(',',$student_id).") ";
            } else {
                $condition_user = " WHERE post.poster_id = '$student_id' ";
            }

            $condition_session = "";
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = " AND forum.session_id = $session_id";
            }

            $sql = "SELECT 1 FROM $tbl_forum_post post INNER JOIN $tbl_forum forum ON forum.forum_id = post.forum_id $condition_user $condition_session ";
            $rs = Database::query($sql);
            return Database::num_rows($rs);
        }
        else
        {
            return null;
        }
    }

    /**
    * This function counts the number of post by course
    * @param      string     Course code
    * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
    * @return    int     The number of post by course
    */
    public static function count_number_of_posts_by_course($course_code, $session_id = null) {
        //protect data
        $course_code = Database::escape_string($course_code);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        $count = 0;
        if (!empty($a_course['db_name'])) {
            $tbl_posts = Database :: get_course_table(TABLE_FORUM_POST, $a_course['db_name']);
            $tbl_forums = Database :: get_course_table(TABLE_FORUM, $a_course['db_name']);
            $condition_session = '';
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = ' WHERE f.session_id = '. $session_id;
            }
            $sql = "SELECT count(*) FROM $tbl_posts p INNER JOIN $tbl_forums f ON f.forum_id = p.forum_id $condition_session ";
            $result = Database::query($sql);
            $row = Database::fetch_row($result);
            $count = $row[0];
            return $count;
        } else {
            return null;
        }
    }

    /**
    * This function counts the number of threads by course
    * @param      string     Course code
    * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
    * @return    int     The number of threads by course
    */
    public static function count_number_of_threads_by_course($course_code, $session_id = null) {
        //protect data
        $course_code = Database::escape_string($course_code);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        $count = 0;
        if (!empty($a_course['db_name'])) {
            $tbl_threads = Database :: get_course_table(TABLE_FORUM_THREAD, $a_course['db_name']);
            $tbl_forums = Database :: get_course_table(TABLE_FORUM, $a_course['db_name']);
            $condition_session = '';
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = ' WHERE f.session_id = '. $session_id;
            }
            $sql = "SELECT count(*) FROM $tbl_threads t INNER JOIN $tbl_forums f ON f.forum_id = t.forum_id $condition_session ";
            $result = Database::query($sql);
            $row = Database::fetch_row($result);
            $count = $row[0];
            return $count;
        } else {
            return null;
        }
    }

    /**
    * This function counts the number of forums by course
    * @param      string     Course code
    * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
    * @return    int     The number of forums by course
    */
    public static function count_number_of_forums_by_course($course_code, $session_id = null) {
        //protect data
        $course_code = addslashes($course_code);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        $count = 0;
        if (!empty($a_course['db_name'])) {

            $condition_session = '';
            if (isset($session_id)) {
                $session_id = intval($session_id);
                $condition_session = ' WHERE session_id = '. $session_id;
            }

            $tbl_forums = Database :: get_course_table(TABLE_FORUM, $a_course['db_name']);
            $sql = "SELECT count(*) FROM $tbl_forums $condition_session";
            $result = Database::query($sql);
            $row = Database::fetch_row($result);
            $count = $row[0];
            return $count;
        } else {
            return null;
        }
    }

    /**
    * This function counts the chat last connections by course in x days
    * @param      string     Course code
    * @param      int     Last x days
    * @param    int        Session id (optional)
    * @return     int     Chat last connections by course in x days
    */
    public static function chat_connections_during_last_x_days_by_course($course_code,$last_days, $session_id = 0) {
        //protect data
        $last_days   = intval($last_days);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);
        // get the informations of the course
        $a_course = CourseManager :: get_course_information($course_code);
        $count = 0;
        if (!empty($a_course['db_name'])) {
            $tbl_stats_access = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_ACCESS, $a_course['db_name']);

            $sql = "SELECT count(*) FROM $tbl_stats_access WHERE DATE_SUB(NOW(),INTERVAL $last_days DAY) <= access_date
                    AND access_cours_code = '$course_code' AND access_tool='".TOOL_CHAT."' AND access_session_id='$session_id' ";
            $result = Database::query($sql);
            $row = Database::fetch_row($result);
            $count = $row[0];
            return $count;
        } else {
            return null;
        }
    }

    /**
    * This function gets the last student's connection in chat
    * @param      int     Student id
    * @param      string     Course code
    * @param    int        Session id (optional)
    * @return     string    datetime formatted without day (e.g: February 23, 2010 10:20:50 )
    */
    public static function chat_last_connection($student_id, $course_code, $session_id = 0) {

        //protect datas
        $student_id = intval($student_id);
        $course_code= Database::escape_string($course_code);
        $session_id    = intval($session_id);
        $date_time  = '';

        // table definition
        $tbl_stats_access = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_LASTACCESS);
        $sql = "SELECT access_date FROM $tbl_stats_access
                 WHERE access_tool='".TOOL_CHAT."' AND access_user_id='$student_id' AND access_cours_code = '$course_code' AND access_session_id = '$session_id' ORDER BY access_date DESC limit 1";
        $rs = Database::query($sql);
        if (Database::num_rows($rs) > 0) {
            $row = Database::fetch_array($rs);
            $date_time = api_convert_and_format_date($row['access_date'], null, date_default_timezone_get());
        }
        return $date_time;
    }

    /**
     * Get count student's visited links
     * @param    int        Student id
     * @param    string    Course code
     * @param    int        Session id (optional)
     * @return    int        count of visited links
     */
    public static function count_student_visited_links($student_id, $course_code, $session_id = 0) {

        // protect datas
        $student_id  = intval($student_id);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);

        // table definition
        $tbl_stats_links = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_LINKS);

        $sql = 'SELECT 1
                        FROM '.$tbl_stats_links.'
                        WHERE links_user_id= '.$student_id.'
                        AND links_cours_id = "'.$course_code.'"
                        AND links_session_id = '.$session_id.' ';

        $rs = Database::query($sql);
        return Database::num_rows($rs);
    }

    /**
     * Get count student downloaded documents
     * @param    int        Student id
     * @param    string    Course code
     * @param    int        Session id (optional)
     * @return    int        Count downloaded documents
     */
    public static function count_student_downloaded_documents($student_id, $course_code, $session_id = 0) {
        // protect datas
        $student_id  = intval($student_id);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);

        // table definition
        $tbl_stats_documents = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_DOWNLOADS);

        $sql = 'SELECT 1
                        FROM ' . $tbl_stats_documents . '
                        WHERE down_user_id = '.$student_id.'
                        AND down_cours_id  = "'.$course_code.'"
                        AND down_session_id = '.$session_id.' ';
        $rs = Database::query($sql);
        return Database::num_rows($rs);
    }

    /**
     * Get course list inside a session from a student
     * @param    int        Student id
     * @param    int        Session id (optional)
     * @return    array    Courses list
     */
    public static function get_course_list_in_session_from_student($user_id, $id_session = 0) {
        $user_id = intval($user_id);
        $id_session = intval($id_session);
        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $sql = 'SELECT course_code FROM ' . $tbl_session_course_user . ' WHERE id_user="' . $user_id . '" AND id_session="' . $id_session . '"';
        $result = Database::query($sql);
        $a_courses = array ();
        while ($row = Database::fetch_array($result)) {
            $a_courses[$row['course_code']] = $row['course_code'];
        }
        return $a_courses;
    }

    /**
     * Get inactives students in course
     * @param    string    Course code
     * @param    string    Since login course date (optional, default = 'never')
     * @param    int        Session id    (optional)
     * @return    array    Inactives users
     */
    public static function get_inactives_students_in_course($course_code, $since = 'never', $session_id=0) {
        $tbl_track_login = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);
        $tbl_session_course_user = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $table_course_rel_user            = Database :: get_main_table(TABLE_MAIN_COURSE_USER);
        $inner = '';
        if($session_id!=0)
        {
            $inner = ' INNER JOIN '.$tbl_session_course_user.' session_course_user
                        ON stats_login.course_code = session_course_user.course_code
                        AND session_course_user.id_session = '.intval($session_id).'
                        AND session_course_user.id_user = stats_login.user_id ';
        }
        $sql = 'SELECT user_id, MAX(login_course_date) max_date FROM'.$tbl_track_login.' stats_login'.$inner.'
                GROUP BY user_id
                HAVING DATE_SUB( NOW(), INTERVAL '.$since.' DAY) > max_date ';
        //HAVING DATE_ADD(max_date, INTERVAL '.$since.' DAY) < NOW() ';

        if ($since == 'never') {
            $sql = 'SELECT course_user.user_id FROM '.$table_course_rel_user.' course_user
                        LEFT JOIN '. $tbl_track_login.' stats_login
                        ON course_user.user_id = stats_login.user_id AND relation_type<>'.COURSE_RELATION_TYPE_RRHH.' '.
                        $inner.'
                    WHERE course_user.course_code = \''.Database::escape_string($course_code).'\'
                    AND stats_login.login_course_date IS NULL
                    GROUP BY course_user.user_id';
        }
        $rs = Database::query($sql);
        $inactive_users = array();
        while($user = Database::fetch_array($rs))
        {
            $inactive_users[] = $user['user_id'];
        }
        return $inactive_users;
    }

    /**
     * Get count login per student
     * @param    int        Student id
     * @param    string    Course code
     * @param    int        Session id (optional)
     * @return    int        count login
     */
    public static function count_login_per_student($student_id, $course_code, $session_id = 0) {
        $student_id  = intval($student_id);
        $course_code = Database::escape_string($course_code);
        $session_id  = intval($session_id);
        $tbl_course_rel_user = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_ACCESS);

        $sql = 'SELECT '.$student_id.'
        FROM ' . $tbl_course_rel_user . '
        WHERE access_user_id=' . $student_id . '
        AND access_cours_code="' . $course_code . '" AND access_session_id = "'.$session_id.'" ';

        $rs = Database::query($sql);
        $nb_login = Database::num_rows($rs);

        return $nb_login;
    }


    /**
     * Get students followed by a human resources manager
     * @param    int        Drh id
     * @return    array    Student list
     */
    public static function get_student_followed_by_drh($hr_dept_id) {

        $hr_dept_id = intval($hr_dept_id);
        $a_students = array ();

        $tbl_organism = Database :: get_main_table(TABLE_MAIN_ORGANISM);
        $tbl_user = Database :: get_main_table(TABLE_MAIN_USER);

        $sql = 'SELECT DISTINCT user_id FROM '.$tbl_user.' as user
                WHERE hr_dept_id='.$hr_dept_id;
        $rs = Database::query($sql);

        while($user = Database :: fetch_array($rs))
        {
            $a_students[$user['user_id']] = $user['user_id'];
        }

        return $a_students;
    }

    /**
     * Gets the average of test and scorm inside a learning path
     * @param    int     User id
     * @param     string     Course id
     * @return    float    average of test
     * @author     isaac flores paz <florespaz@bidsoftperu.com>
     * @deprecated get_avg_student_score should be use
     */
    public static function get_average_test_scorm_and_lp ($user_id,$course_id) {

        //the score inside the Reporting table
        $course_info    = api_get_course_info($course_id);
        $lp_table         = Database :: get_course_table(TABLE_LP_MAIN,$course_info['dbName']);
        $lp_view_table    = Database  :: get_course_table(TABLE_LP_VIEW,$course_info['dbName']);
        $lp_item_view_table = Database  :: get_course_table(TABLE_LP_ITEM_VIEW,$course_info['dbName']);
        $lp_item_table = Database  :: get_course_table(TABLE_LP_ITEM,$course_info['dbName']);
        $sql_type='SELECT id, lp_type FROM '.$lp_table;
        $rs_type=Database::query($sql_type);
        $average_data=0;
        $count_loop=0;
        $lp_list = array();
        while ($row_type=Database::fetch_array($rs_type)) {
            $lp_list[] = $row_type['id'];
            if ($row_type['lp_type']==1) {
                    //lp dokeos

                    $sql = "SELECT id FROM $lp_view_table  WHERE user_id = '".intval($user_id)."' and lp_id='".$row_type['id']."'";
                    $rs_last_lp_view_id = Database::query($sql);
                    $lp_view_id = intval(Database::result($rs_last_lp_view_id,0,'id'));

                    $sql_list_view='SELECT li.max_score,lv.user_id,liw.score,(liw.score/li.max_score) as sum_data FROM '.$lp_item_table.' li INNER JOIN '.$lp_view_table.' lv
                    ON li.lp_id=lv.lp_id INNER JOIN '.$lp_item_view_table.' liw ON liw.lp_item_id=li.id WHERE lv.user_id="'.$user_id.'" AND li.item_type="quiz" AND liw.lp_view_id="'.$lp_view_id.'"';
                    $sum=0;
                    $tot=0;
                    $rs_list_view1=Database::query($sql_list_view);
                    while ($row_list_view=Database::fetch_array($rs_list_view1)) {
                        $sum=$sum+$row_list_view['sum_data'];
                        $tot++;
                    }
                    if ($tot==0) {
                        $tot=1;
                    }
                    $average_data1=$sum/$tot;

                    $sql_list_view='';
                    $rs_last_lp_view_id='';

            } elseif ($row_type['lp_type']==2) {//lp scorm
                    $sql = "SELECT id FROM $lp_view_table  WHERE user_id = '".intval($user_id)."' and lp_id='".$row_type['id']."'";
                    $rs_last_lp_view_id = Database::query($sql);
                    $lp_view_id = intval(Database::result($rs_last_lp_view_id,0,'id'));

                    $sql_list_view='SELECT li.max_score,lv.user_id,liw.score,((liw.score/li.max_score)*100) as sum_data FROM '.$lp_item_table.' li INNER JOIN '.$lp_view_table.' lv
                    ON li.lp_id=lv.lp_id INNER JOIN '.$lp_item_view_table.' liw ON liw.lp_item_id=li.id WHERE lv.user_id="'.$user_id.'" AND (li.item_type="sco" OR li.item_type="quiz") AND liw.lp_view_id="'.$lp_view_id.'"';
                    $tot=0;
                    $sum=0;

                    $rs_list_view2=Database::query($sql_list_view);
                    while ($row_list_view=Database::fetch_array($rs_list_view2)) {
                        $sum=$sum+$row_list_view['sum_data'];
                        $tot++;
                    }
                    if ($tot==0) {
                        $tot=1;
                    }
                    $average_data2=$sum/$tot;
            }
            $average_data_sum=$average_data_sum+$average_data1+$average_data2;
            $average_data2=0;
            $average_data1=0;
            $count_loop++;
        }

        //We only count the LP that have an exercise to get the average
        $lp_with_quiz = 0;
        foreach($lp_list as $lp_id) {

            //check if LP have a score
            $sql = "SELECT count(id) as count FROM $lp_item_table
                    WHERE item_type = 'quiz' AND lp_id = ".$lp_id." ";
            $result_have_quiz = Database::query($sql);

            if (Database::num_rows($result_have_quiz) > 0 ) {
                $row = Database::fetch_array($result_have_quiz,'ASSOC');
                if (is_numeric($row['count']) && $row['count'] != 0) {
                    $lp_with_quiz++;
                }
            }
        }

        if ($lp_with_quiz > 0) {
            $avg_student_score = round(($average_data_sum / $lp_with_quiz * 100), 2);
        }
        return $avg_student_score;
    }

    /**
     * get count clicks about tools most used by course
     * @param      string     Course code
     * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @return    array     tools data
     */
    public static function get_tools_most_used_by_course($course_code, $session_id = null) {
        //protect data
        $course_code = Database::escape_string($course_code);
        $data = array();
        $TABLETRACK_ACCESS    = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_LASTACCESS);
        $condition_session     = '';
        if (isset($session_id)) {
            $session_id = intval($session_id);
            $condition_session = ' AND access_session_id = '. $session_id;
        }
        $sql = "SELECT access_tool, COUNT(DISTINCT access_user_id),count( access_tool ) as count_access_tool
            FROM $TABLETRACK_ACCESS
            WHERE access_tool IS NOT NULL
                AND access_cours_code = '$course_code'
                   $condition_session
            GROUP BY access_tool
            ORDER BY count_access_tool DESC
            LIMIT 0, 3";
        $rs = Database::query($sql);
        if (Database::num_rows($rs) > 0) {
            while ($row = Database::fetch_array($rs)) {
                $data[] = $row;
            }
        }
        return $data;
    }

    /**
     * get documents most downloaded by course
     * @param      string     Course code
     * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @param    int        Limit (optional, default = 0, 0 = without limit)
     * @return    array     documents downloaded
     */
    public static function get_documents_most_downloaded_by_course($course_code, $session_id = null, $limit = 0) {

        //protect data
        $course_code = Database::escape_string($course_code);
        $data = array();

        $TABLETRACK_DOWNLOADS   = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_DOWNLOADS);
        $condition_session = '';
        if (isset($session_id)) {
            $session_id = intval($session_id);
            $condition_session = ' AND down_session_id = '. $session_id;
        }
        $sql = "SELECT down_doc_path, COUNT(DISTINCT down_user_id), COUNT(down_doc_path) as count_down
            FROM $TABLETRACK_DOWNLOADS
            WHERE down_cours_id = '$course_code'
            $condition_session
            GROUP BY down_doc_path
            ORDER BY count_down DESC
            LIMIT 0,  $limit";
        $rs = Database::query($sql);

        if (Database::num_rows($rs) > 0) {
            while ($row = Database::fetch_array($rs)) {
                $data[] = $row;
            }
        }
        return $data;
    }

    /**
     * get links most visited by course
     * @param      string     Course code
     * @param    int        Session id (optional), if param $session_id is null(default) it'll return results including sessions, 0 = session is not filtered
     * @return    array     links most visited
     */
    public static function get_links_most_visited_by_course($course_code, $session_id = null) {

        //protect data
        $course_code = Database::escape_string($course_code);
        $course_info=api_get_course_info($course_code);
        $data = array();

        $TABLETRACK_LINKS       = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_LINKS);
        $TABLECOURSE_LINKS      = Database::get_course_table(TABLE_LINK, $course_info['dbName']);

        $condition_session = '';
        if (isset($session_id)) {
            $session_id = intval($session_id);
            $condition_session = ' AND cl.session_id = '.$session_id;
        }

        $sql = "SELECT cl.title, cl.url,count(DISTINCT sl.links_user_id), count(cl.title) as count_visits
            FROM $TABLETRACK_LINKS AS sl, $TABLECOURSE_LINKS AS cl
            WHERE sl.links_link_id = cl.id
                AND sl.links_cours_id = '$_cid'
                $condition_session
            GROUP BY cl.title, cl.url
            ORDER BY count_visits DESC
            LIMIT 0, 3";
        $rs = Database::query($sql);
        if (Database::num_rows($rs) > 0) {
            while ($row = Database::fetch_array($rs)) {
                $data[] = $row;
            }
        }
        return $data;
    }
    
    /**
     * Shows the user progress (when clicking in the Progress tab)
     * @param   int     user id
     * @return  string  html code
     */
    function show_user_progress($user_id, $session_id = 0, $extra_params = '', $show_courses = true) {
        global $_configuration;
        $tbl_course_user            = Database :: get_main_table(TABLE_MAIN_COURSE_USER);
        $tbl_access_rel_course      = Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
        $tbl_session_course_user    = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
        $tbl_access_rel_session     = Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_SESSION);
        $tbl_access_rel_course      = Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
        $user_id                    = intval($user_id);
        
       // get course list
        if ($_configuration['multiple_access_urls']) {    
            $sql = 'SELECT cu.course_code FROM '.$tbl_course_user.' cu INNER JOIN '.$tbl_access_rel_course.' a  ON(a.course_code = cu.course_code) WHERE user_id='.$user_id.' AND relation_type<>'.COURSE_RELATION_TYPE_RRHH.' AND access_url_id = '.api_get_current_access_url_id().'';
        } else {
            $sql = 'SELECT course_code FROM '.$tbl_course_user.' WHERE user_id='.$user_id.' AND relation_type<>'.COURSE_RELATION_TYPE_RRHH.' ';
        }
    
        $rs = Database::query($sql);
        $courses = $course_in_session = array();
        
        while($row = Database :: fetch_array($rs)) {
            $courses[$row['course_code']] = CourseManager::get_course_information($row['course_code']);
        }
    
        // Get the list of sessions where the user is subscribed as student
        if ($_configuration['multiple_access_urls']) {
            $sql = 'SELECT DISTINCT cu.course_code, id_session as session_id FROM '.$tbl_session_course_user.' cu INNER JOIN '.$tbl_access_rel_session.' a  ON(a.session_id = cu.id_session) WHERE id_user='.$user_id.' AND access_url_id = '.api_get_current_access_url_id().'';
        } else {
            $sql = 'SELECT DISTINCT course_code, id_session as session_id FROM '.$tbl_session_course_user.' WHERE id_user='.$user_id;
        }
        
        $rs = Database::query($sql);
        while($row = Database :: fetch_array($rs)) {
            $course_in_session[$row['session_id']][$row['course_code']] = CourseManager::get_course_information($row['course_code']);
        }        
        
        $html  = '';
        if ($show_courses) {                   
            if (!empty($courses)) {
                $html .= '<table class="data_table" width="100%">';
                $html .= '<tr class="tableName">
                            <td colspan="6">
                                '.Display::tag('h1', get_lang('MyCourses')).'
                            </td>
                        </tr>';
                $html .= '
                <tr>                  
                  '.Display::tag('th', get_lang('Course'),          array('width'=>'300px')).'
                  '.Display::tag('th', get_lang('Time'),            array('class'=>'head')).'
                  '.Display::tag('th', get_lang('Progress'),        array('class'=>'head')).'
                  '.Display::tag('th', get_lang('Score').Display :: return_icon('info3.gif', get_lang('ScormAndLPTestTotalAverage'), array('align' => 'absmiddle', 'hspace' => '3px')),array('class'=>'head')).'
                  '.Display::tag('th', get_lang('LastConnexion'),   array('class'=>'head')).'      
                  '.Display::tag('th', get_lang('Details'),         array('class'=>'head')).'
                </tr>';
              
                $i = 0;
                foreach ($courses as $enreg) {
                    $weighting = 0;
                    
                    $total_time_login      = Tracking :: get_time_spent_on_the_course($user_id, $enreg['code']);
                    $time                  = api_time_to_hms($total_time_login);
                    $progress              = Tracking :: get_avg_student_progress($user_id, $enreg['code']);
                    $percentage_score      = Tracking :: get_avg_student_score($user_id, $enreg['code'], array());
                    $last_connection       = Tracking :: get_last_connection_date_on_the_course($user_id, $enreg['code']);
                    
                
                    if ($enreg['code'] == $_GET['course'] && empty($_GET['session_id'])) {
                        $html .= '<tr class="row_odd" style="background-color:#FBF09D">';
                    } else {
                        $html .= '<tr class="row_even">';
                    }
                    $url = api_get_course_url($enreg['code'], $session_id);
                    $course_url = Display::url($enreg['title'], $url, array('target'=>'_blank'));
                    $html .= '<td>'.$course_url.'</td>';
                    
                    $html .= '<td align="center">'.$time.'</td>';
                    $html .= '<td align="center">'.$progress.'%</td>';
                    
                    $html .= '<td align="center">';
                    if (is_numeric($percentage_score)) {
                        $html .= $percentage_score.'%';
                    } else {
                        $html .= '0%';
                    }   
                    $html .= '</td>';        
                    $html .= '<td align="center">'.$last_connection.'</td>';        
                    $html .= '<td align="center">';     
                    if ($enreg['code'] == $_GET['course'] && empty($_GET['session_id'])) {
                        $html .= '<a href="#">';
                        $html .= Display::return_icon('2rightarrow_na.gif', get_lang('Details'));
                    } else {
                        $html .= '<a href="'.api_get_self().'?course='.$enreg['code'].$extra_params.'">';
                        $html .= Display::return_icon('2rightarrow.gif', get_lang('Details'));
                    }
                    $html .= '</a>';
                    $html .= '</td></tr>';
                    $i = $i ? 0 : 1;
                }    
                $html .= '</table>';
            }
        }
        
        //Session
        if (!empty($course_in_session)) {
            $html .= '<br />';
            $html .= Display::tag('h1',get_lang('Sessions'));
            
            foreach ($course_in_session as $key=>$session) {  
                if (isset($session_id) && !empty($session_id)) {
                    if ($session_id != $key) {                       
                    	continue;
                    }
                }                
                $html .= Display::tag('h2',api_get_session_name($key));
                
                $html .= '<table class="data_table" width="100%">';    
                $html .= '
                <tr>                  
                  '.Display::tag('th', get_lang('PublishedExercises'),       array('width'=>'300px')).'
                  '.Display::tag('th', get_lang('DoneExercises'),            array('class'=>'head')).'
                  '.Display::tag('th', get_lang('AverageExerciseResult'),    array('class'=>'head')).'                  
                </tr>';
                

                $all_exercises = 0;
                $all_done_exercise = 0;
                $all_average = 0;
                
                $stats_array = array();
                
                foreach ($session as $enreg) {    
                    //All exercises in the course
                    $exercises      = count(get_all_exercises($enreg, $key));
                    //Count of user results
                    $done_exercises = get_all_exercise_results_by_course($enreg['code'], $key);
                    //Average
                    $average        = get_average_score_by_course($enreg['code'], $key);
                    
                    $all_exercises +=$exercises;
                    $all_done_exercise +=$done_exercises;
                    $all_average +=$average;
                    $stats_array[$enreg['code']] = array('exercises'=>$exercises, 'done_exercises'=>$done_exercises, 'average'=>$average);
                }         
                $all_average = $all_average /  count($session);     
                $html .= Display::tag('td', $all_exercises);
                $html .= Display::tag('td', $all_done_exercise);
                $html .= Display::tag('td', convert_to_percentage($all_average));
                $html .='</table><br />';
                    
                
                $html .= Display::tag('h2',get_lang('CourseList'));
                
                $html .= '        
                <table class="data_table" width="100%">';
                $html .= '
                    <tr>
                      <th width="300px">'.get_lang('Course').'</th>
                      '.Display::tag('th', get_lang('PublishedExercises'),array('class'=>'head')).'
                      '.Display::tag('th', get_lang('DoneExercises'),     array('class'=>'head')).'
                      '.Display::tag('th', get_lang('AverageExerciseResult'),     array('class'=>'head')).'
                      '.Display::tag('th', get_lang('Time')         ,     array('class'=>'head')).'
                      '.Display::tag('th', get_lang('LPProgress')     ,   array('class'=>'head')).'
                      '.Display::tag('th', get_lang('Score').Display :: return_icon('info3.gif', get_lang('ScormAndLPTestTotalAverage'), array ('align' => 'absmiddle', 'hspace' => '3px')), array('class'=>'head')).'
                      '.Display::tag('th', get_lang('LastConnexion'),     array('class'=>'head')).'      
                      '.Display::tag('th', get_lang('Details'),           array('class'=>'head')).'
                    </tr>';
                foreach ($session as $enreg) {               
                    $weighting = 0;
                    $last_connection       = Tracking :: get_last_connection_date_on_the_course($user_id, $enreg['code'], $key);
                    $progress              = Tracking :: get_avg_student_progress($user_id, $enreg['code'],array(), $key);                    
                    $total_time_login      = Tracking :: get_time_spent_on_the_course($user_id, $enreg['code'], $key);
                    $time                  = api_time_to_hms($total_time_login);
                    $percentage_score      = Tracking :: get_avg_student_score($user_id, $enreg['code'], array(), $key);
                    
                    if ($enreg['code'] == $_GET['course'] && $_GET['session_id'] == $key) {
                        $html .= '<tr  class="row_odd" style="background-color:#FBF09D" >';
                    } else {
                        $html .= '<tr  class="row_even">';
                    }
                    
                    $url = api_get_course_url($enreg['code'], $key);
                    $course_url = Display::url($enreg['title'], $url, array('target'=>'_blank'));
                    
                    $html .= Display::tag('td', $course_url);/*
                    //All exercises in the course
                    $exercises = get_all_exercises($enreg, $key);
                    //Count of user results
                    $done_exercises = get_all_exercise_results_by_course($enreg['code'], $key);
                    //Average
                    $average = get_average_score_by_course($enreg['code'], $key);*/
                    
                    $html .= Display::tag('td', $stats_array[$enreg['code']]['exercises']);
                    $html .= Display::tag('td', $stats_array[$enreg['code']]['done_exercises']);
                    $html .= Display::tag('td', convert_to_percentage($stats_array[$enreg['code']]['average']));
                    $html .= Display::tag('td', $time, array('align'=>'center'));
                                        
                    if (is_numeric($progress)) {
                        $progress = $progress.'%';
                    } else {
                        $progress = '0%';
                    }
                    $html .= Display::tag('td', $progress, array('align'=>'center'));                    
                    if (is_numeric($percentage_score)) {
                        $percentage_score = $percentage_score.'%';
                    } else {
                        $percentage_score = '0%';
                    }   
                    $html .= Display::tag('td', $percentage_score, array('align'=>'center'));                         
                    $html .= Display::tag('td', $last_connection, array('align'=>'center')); 
                        
                    if ($enreg['code'] == $_GET['course'] && $_GET['session_id'] == $key) {
                        $details = '<a href="#">';
                        $details .=Display::return_icon('2rightarrow_na.gif', get_lang('Details'));
                    } else {
                        $details = '<a href="'.api_get_self().'?course='.$enreg['code'].'&session_id='.$key.$extra_params.'">';
                        $details .=Display::return_icon('2rightarrow.gif', get_lang('Details'));
                    }
                    $details .= '</a>';                    
               
                    $html .= Display::tag('td', $details, array('align'=>'center')); 
                    
                    $i = $i ? 0 : 1;
                    $html .= '</tr>';
                }
                $html .= '</table>';  
            }            
        }
        return $html;
    }
        
        
    /**
     * Shows the user detail progress (when clicking in the details link)
     * @param   int     user id
     * @param   string  course code
     * @param   int     session id
     * @return  string  html code
     */
    function show_course_detail($user_id, $course_code, $session_id) {        
        $html = '';
        if (isset($course_code)) {
            require_once api_get_path(SYS_CODE_PATH).'exercice/exercise.lib.php';
            
            $user_id                    = intval($user_id);
            $session_id                 = intval($session_id);
            $course                     = Database::escape_string($course_code);            
            $course_info                = CourseManager::get_course_information($course);
            
            $tbl_user                   = Database :: get_main_table(TABLE_MAIN_USER);
            $tbl_session                = Database :: get_main_table(TABLE_MAIN_SESSION);
            $tbl_session_course         = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE);
            $tbl_session_course_user    = Database :: get_main_table(TABLE_MAIN_SESSION_COURSE_USER);
            $tbl_course_lp_view         = Database :: get_course_table(TABLE_LP_VIEW,   $course_info['db_name']);
            $tbl_course_lp_view_item    = Database :: get_course_table(TABLE_LP_ITEM_VIEW, $course_info['db_name']);
            $tbl_course_lp              = Database :: get_course_table(TABLE_LP_MAIN,   $course_info['db_name']);
            $tbl_course_lp_item         = Database :: get_course_table(TABLE_LP_ITEM,   $course_info['db_name']);
            $tbl_course_quiz            = Database :: get_course_table(TABLE_QUIZ_TEST, $course_info['db_name']);    
            
            $session_name = api_get_session_name($session_id);
                            
            $html .='
            <table class="data_table" width="100%">
                <tr class="tableName">
                    <td colspan="4">
                        '.Display::tag('h3', $course_info['title']).'
                    </td>
                </tr><tr>';                
                
            $html .= Display::tag('th', get_lang('Learnpath'),     array('class'=>'head', 'style'=>'color:#000'));
            $html .= Display::tag('th', get_lang('Time'),          array('class'=>'head', 'style'=>'color:#000'));
            $html .= Display::tag('th', get_lang('Progress'),      array('class'=>'head', 'style'=>'color:#000'));
            $html .= Display::tag('th', get_lang('LastConnexion'), array('class'=>'head', 'style'=>'color:#000'));
            $html .= '</tr>';
            
            if (empty($session_id)) {
                $sql_learnpath = "SELECT lp.name,lp.id FROM ".$tbl_course_lp." AS lp  WHERE session_id = 0 ORDER BY lp.display_order";
            } else {
                $sql_learnpath = "SELECT lp.name,lp.id FROM ".$tbl_course_lp." AS lp ORDER BY lp.display_order";
            }
            
            $result_learnpath = Database::query($sql_learnpath);
            if (Database::num_rows($result_learnpath) > 0) {
                while($learnpath = Database::fetch_array($result_learnpath)) {                       
                    $progress               = Tracking::get_avg_student_progress($user_id, $course, array($learnpath['id']), $session_id);                        
                    $last_connection_in_lp  = Tracking::get_last_connection_time_in_lp($user_id, $course, $learnpath['id'], $session_id);
                    $time_spent_in_lp       = Tracking::get_time_spent_in_lp($user_id, $course, array($learnpath['id']), $session_id);
                    $time_spent_in_lp       = api_time_to_hms($time_spent_in_lp);                            
                                  
                    $html .= '<tr class="row_even">';
                    $html .= Display::tag('td', $learnpath['name']);
                    $html .= Display::tag('td', $time_spent_in_lp, array('align'=>'center'));
                    if (is_numeric($progress)) {
                        $progress = $progress.'%';
                    }                    
                    $html .= Display::tag('td', $progress, array('align'=>'center'));
                    $last_connection = '-';                                                                
                    if (!empty($last_connection_in_lp)) {
                        $last_connection = api_get_utc_datetime($last_connection_in_lp);
                    }
                    $html .= Display::tag('td', $last_connection, array('align'=>'center','width'=>'180px'));
                    $html .= "</tr>";
                }
            } else {
                $html .= '<tr>
                          	<td colspan="4" align="center">
                            	'.get_lang('NoLearnpath').'
							</td>
						  </tr>';
            }
            
            $html .='</table><br />
            <table class="data_table" width="100%">';     
                     
                        
            // This code was commented on purpose see BT#924

            /*$sql = 'SELECT visibility FROM '.$course_info['db_name'].'.'.TABLE_TOOL_LIST.' WHERE name="quiz"';
            $result_visibility_tests = Database::query($sql);

            if (Database::result($result_visibility_tests, 0, 'visibility') == 1) {*/
            
            //Course details     
            $html .= '<tr>                
                <th class="head" style="color:#000">'.get_lang('Exercices').'</th>
                <th class="head" style="color:#000">'.get_lang('Attempts').'</th>                    
                <th class="head" style="color:#000">'.get_lang('LatestAttempt').'</th>
                <th class="head" style="color:#000">'.get_lang('Ranking').'</th>
                <th class="head" style="color:#000">'.get_lang('BestResultInCourse').'</th>
                <th class="head" style="color:#000">'.get_lang('Statistics').'</th>                                        
                </tr>';
            
            if (empty($session_id)) {
                $sql_exercices = "SELECT quiz.title,id, results_disabled FROM ".$tbl_course_quiz." AS quiz WHERE active='1' AND session_id = 0";
            } else {
                $sql_exercices = "SELECT quiz.title,id, results_disabled FROM ".$tbl_course_quiz." AS quiz WHERE active='1'";
            }
            $result_exercices = Database::query($sql_exercices);
            $to_graph_exercise_result = array();
            if (Database::num_rows($result_exercices) > 0) {
                
                while ($exercices = Database::fetch_array($result_exercices)) {
                    //if ($exercices['id'] != 3) continue;
                    $score = $weighting = $attempts = 0;                        
                    $exercise_stats      = get_all_exercise_results($exercices['id'], $course_info['code'], $session_id);                    
                    $best_exercise_stats = get_all_best_exercise_results_by_user($exercices['id'], $course_info['code'], $session_id);
                   
                    
                    //User attempts we assume the latest item in the loop is the latest attempt
                    if (!empty($exercise_stats)) {
                        //$best_score = 0; $best_score_array = array();
                        foreach($exercise_stats as $exercise_stat) {
                            if ($exercise_stat['exe_user_id'] == $user_id) {
                                
                               //Always getting the latest attempt
                               $score          = $exercise_stat['exe_result'];
                               $weighting      = $exercise_stat['exe_weighting'];                               
                               $exe_id         = $exercise_stat['exe_id'];
                               
                               //Use this to take the average
                               //$score          = $score + $exercise_stat['exe_result'];
                               //$weighting      = $weighting + $exercise_stat['exe_weighting'];
                               
                               //Getting my best score
                               /*
                               if ($score > $best_score ) {
                                   $best_score = $score;
                                   $best_score_array = $exercise_stat;
                               }*/                       
                               $attempts++;
                            }
                        }
                    }
                    $to_graph_exercise_result[$exercices['id']] = array('title'=>$exercices['title'], 'data'=>$best_exercise_stats);
                    
                    $html .= '<tr class="row_even">';
                    $url = api_get_path(WEB_CODE_PATH)."exercice/exercice_submit.php?cidReq={$course_info['code']}&id_session=$session_id&exerciseId={$exercices['id']}";
                    $exercices['title'] = Display::url($exercices['title'], $url, array('target'=>'_blank'));
                    $html .= Display::tag('td', $exercices['title']);
                    
                    //Exercise configuration show results
                    if ($exercices['results_disabled'] == 0) {
                        $latest_attempt_url = '';
                        $percentage_score_result  = '-';
                        $position = '-';
                        $best_score = '-';
                        
                        $best_score_data = get_best_score($exercices['id'], $course_info['code'], $session_id);     
                        $best_score      = show_score($best_score_data['exe_result'], $best_score_data['exe_weighting']);
                                               
                        if ($attempts > 0) {
                            $latest_attempt_url .= '<a href="../exercice/exercise_show.php?origin=myprogress&id='.$exe_id.'&cidReq='.$course_info['code'].'&id_session='.$session_id.'"> '.Display::return_icon('quiz.gif', get_lang('Quiz')).' </a>';
                            $percentage_score_result = show_score($score, $weighting).' '.$latest_attempt_url;
                            $my_score = 0;                            
                            if (!empty($weighting)) {                                                           
                                $my_score = $score/$weighting;
                            }                            
                            $position = get_exercise_result_ranking($my_score, $exe_id, $exercices['id'], $course_info['code'], $session_id);                            
                        }
                              
                        $graph         = self::generate_exercise_result_thumbnail_graph($to_graph_exercise_result[$exercices['id']]);                        
                        $normal_graph  = self::generate_exercise_result_graph($to_graph_exercise_result[$exercices['id']]);
                        
                        echo Display::div($normal_graph, array('id'=>'main_graph_'.$exercices['id'],'class'=>'dialog', 'style'=>'display:none') );
                        
                        if (empty($graph)) {
                            $graph = '-';
                        } else {
                            $graph = Display::url($graph, '#', array('id'=>$exercices['id'],'class'=>'opener'));  
                        }
                        
                        $html .= Display::tag('td', $attempts,                 array('align'=>'center'));                                          
                        $html .= Display::tag('td', $percentage_score_result,  array('align'=>'center'));
                        $html .= Display::tag('td', $position,                 array('align'=>'center'));                            
                        $html .= Display::tag('td', $best_score,               array('align'=>'center'));
                        $html .= Display::tag('td', $graph,                    array('align'=>'center'));
                        
                        //$html .= Display::tag('td', $latest_attempt_url,       array('align'=>'center', 'width'=>'25'));                           
                        
                    } else {
                        // Exercise configuration NO results
                        $html .= Display::tag('td', get_lang('CantShowResults'), array('align'=>'center'));  
                        $html .= Display::tag('td', '--', array('align'=>'center'));                            
                        $html .= Display::tag('td', '--', array('align'=>'center'));
                        $html .= Display::tag('td', '--', array('align'=>'center'));
                        $html .= Display::tag('td', '--', array('align'=>'center'));                            
                    }
                    $html .= '</tr>';
                }
            } else {
                $html .= '<tr><td colspan="5" align="center">'.get_lang('NoEx').'</td></tr>';
            }
            $html .= '</table>';
        }
        return $html;
    }
    
    function generate_exercise_result_thumbnail_graph($attempts) {       
        require_once api_get_path(LIBRARY_PATH).'pchart/pData.class.php';
	    require_once api_get_path(LIBRARY_PATH).'pchart/pChart.class.php';
	    require_once api_get_path(LIBRARY_PATH).'pchart/pCache.class.php';    
    
        $exercise_title = $attempts['title'];	
        $attempts       = $attempts['data']; 	        
        $my_exercise_result_array = $exercise_result = array();
        if (empty($attempts)) {
            return null;
        }
       
        foreach ($attempts as $attempt) {         
            if (api_get_user_id() == $attempt['exe_user_id']) {
                if ($attempt['exe_weighting'] != 0 ) {
                    $my_exercise_result_array[]= $attempt['exe_result']/$attempt['exe_weighting'];
                }     
            } else {
                if ($attempt['exe_weighting'] != 0 ) {		                
                    $exercise_result[]=  $attempt['exe_result']/$attempt['exe_weighting'];
                }   
            }		            
        }
        
        //Getting best result		        
        rsort($my_exercise_result_array);        
        $my_exercise_result = 0;
        if (isset($my_exercise_result_array[0])) {            	           		            
            $my_exercise_result = $my_exercise_result_array[0] *100;		            
        }
        
        //var_dump($exercise_result, $my_exercise_result);
        
        $max = 100;
        $pieces = 5 ;
        $part = round($max / $pieces);
        $x_axis = array();
        $final_array = array();
        $my_final_array = array();
        
        for ($i=1; $i <=$pieces; $i++) {
            $sum = 1;
            if ($i == 1) {
                $sum = 0;
            }
            $min = ($i-1)*$part + $sum;
            $max = ($i)*$part;
            $x_axis[]= $min." - ".$max;
            $count = 0;
            foreach($exercise_result as $result) {
                $percentage = $result*100;
                //echo $percentage.' - '.$min.' - '.$max."<br />";                    
                if ($percentage >= $min && $percentage <= $max) {
                    //echo ' is > ';                            
                    $count++;
                }
            }
            //echo '<br />';           
            $final_array[]= $count;
            
            if ($my_exercise_result >= $min && $my_exercise_result <= $max) {
                $my_final_array[] = 1;
            } else {
                $my_final_array[] = 0;
            }                    
        }
        
        //var_dump($my_final_array, $final_array); exit;
        
        //Fix to remove the data of the user with my data
        
        for($i = 0; $i<=count($my_final_array); $i++) {
            if (!empty($my_final_array[$i])) {
                $my_final_array[$i] =  $final_array[$i] + 1; //Add my result                  
                $final_array[$i] = 0;                
            }
        }
        //var_dump($my_final_array, $final_array); echo '<br />'; 
        
        //echo '<pre>'; var_dump($my_exercise_result, $exercise_result,$x_axis);
               
        $cache = new pCache();                
        
         // Dataset definition   
        $data_set = new pData();
        $data_set->AddPoint($final_array,"Serie1");  
        $data_set->AddPoint($my_final_array,"Serie2");
        //$data_set->AddPoint($x_axis,"Serie3");
        $data_set->AddAllSeries();  
               
        // Initialise the graph  
        
        $main_width  = 80;
        $main_height = 35;
        
        $Test = new pChart($main_width, $main_height);
        
        $Test->setFontProperties(api_get_path(LIBRARY_PATH).'pchart/fonts/tahoma.ttf',8);                
        //$Test->setGraphArea(50,30,680,200);
        $Test->drawFilledRoundedRectangle(2,2,$main_width-2,$main_height-2,2,230,230,230);
        $Test->setGraphArea(5,5,$main_width-5,$main_height-5);     
        $Test->drawGraphArea(255,255,255);  
        
        //SCALE_NORMAL, SCALE_START0, SCALE_ADDALLSTART0
        $Test->drawScale($data_set->GetData(),$data_set->GetDataDescription(),SCALE_ADDALLSTART0, 150,150,150,FALSE,0,1,TRUE);     
        
        $Test->drawOverlayBarGraph($data_set->GetData(),$data_set->GetDataDescription(), 100);  
        
        // Finish the graph                                  
        $graph_id = 'thumbnail_exercise_result_graph_'.Security::remove_XSS($_GET['course']).'-'.intval($_GET['session_id']).'-'.api_get_user_id();
        
        //if ($cache->IsInCache($graph_id, $data_set->GetData())) {
		if (0) {
			//if we already created the img
			//echo 'in cache';
			$img_file = $cache->GetHash($graph_id,$data_set->GetData());
        } else {
            $cache->WriteToCache($graph_id, $data_set->GetData(), $Test);
            ob_start();
            $Test->Stroke();
            ob_end_clean();            
            $img_file = $cache->GetHash($graph_id, $data_set->GetData());
        }
        $html = '<img src="'.api_get_path(WEB_ARCHIVE_PATH).$img_file.'">';
        return $html;
    }
    
    function generate_exercise_result_graph($attempts) {

        require_once api_get_path(LIBRARY_PATH).'pchart/pData.class.php';
	    require_once api_get_path(LIBRARY_PATH).'pchart/pChart.class.php';
	    require_once api_get_path(LIBRARY_PATH).'pchart/pCache.class.php';
          
        $exercise_title = $attempts['title'];	
        $attempts       = $attempts['data']; 	        
        $my_exercise_result_array = $exercise_result = array();
        if (empty($attempts)) {
            return null;
        }
        foreach ($attempts as $attempt) {         
            if (api_get_user_id() == $attempt['exe_user_id']) {
                if ($attempt['exe_weighting'] != 0 ) {
                    $my_exercise_result_array[]= $attempt['exe_result']/$attempt['exe_weighting'];
                }     
            } else {
                if ($attempt['exe_weighting'] != 0 ) {		                
                    $exercise_result[]=  $attempt['exe_result']/$attempt['exe_weighting'];
                }   
            }		            
        }
        
        //Getting best result		        
        rsort($my_exercise_result_array);        
        $my_exercise_result = 0;
        if (isset($my_exercise_result_array[0])) {            	           		            
            $my_exercise_result = $my_exercise_result_array[0] *100;		            
        }
        
        //var_dump($exercise_result, $my_exercise_result);
        
        $max = 100;
        $pieces = 5 ;
        $part = round($max / $pieces);
        $x_axis = array();
        $final_array = array();
        $my_final_array = array();
        
        for ($i=1; $i <=$pieces; $i++) {
            $sum = 1;
            if ($i == 1) {
                $sum = 0;
            }
            $min = ($i-1)*$part + $sum;
            $max = ($i)*$part;
            $x_axis[]= $min." - ".$max;
            $count = 0;
            foreach($exercise_result as $result) {
                $percentage = $result*100;
                //echo $percentage.' - '.$min.' - '.$max."<br />";                    
                if ($percentage >= $min && $percentage <= $max) {
                    //echo ' is > ';                            
                    $count++;
                }
            }
            //echo '<br />';           
            $final_array[]= $count;
            
            if ($my_exercise_result >= $min && $my_exercise_result <= $max) {
                $my_final_array[] = 1;
            } else {
                $my_final_array[] = 0;
            }                    
        }
        
        //var_dump($my_final_array, $final_array); exit;
        
        //Fix to remove the data of the user with my data
        
        for($i = 0; $i<=count($my_final_array); $i++) {
            if (!empty($my_final_array[$i])) {
                $my_final_array[$i] =  $final_array[$i] + 1; //Add my result                  
                $final_array[$i] = 0;                
            }
        }
        //var_dump($my_final_array, $final_array); echo '<br />'; 
        
        //echo '<pre>'; var_dump($my_exercise_result, $exercise_result,$x_axis);
        
        $cache = new pCache();        
        
        // Dataset definition   
        $data_set = new pData();
        $data_set->AddPoint($final_array,"Serie1");  
        $data_set->AddPoint($my_final_array,"Serie2");
        $data_set->AddPoint($x_axis,"Serie3");
        $data_set->AddAllSeries();  
        
        $data_set->SetAbsciseLabelSerie('Serie3');
        $data_set->SetSerieName(get_lang('Score'),"Serie1");  
        $data_set->SetSerieName(get_lang('MyResults'),"Serie2");        
        
        $data_set->SetXAxisName(get_lang("Score"));                  
        
        // Initialise the graph  
        $main_width  = 500;
        $main_height = 250;
        
        $Test = new pChart($main_width,$main_height);  
        
        $Test->setFontProperties(api_get_path(LIBRARY_PATH).'pchart/fonts/tahoma.ttf',8);  
        $Test->setGraphArea(50,30, $main_width -20,$main_height -50);  
        
        $Test->drawFilledRoundedRectangle(10,10, $main_width- 10,$main_height -10,5,240,240,240);  
        $Test->drawRoundedRectangle(7,7,$main_width - 7,$main_height  - 7,5,230,230,230);  
        
        $Test->drawGraphArea(255,255,255,TRUE);  
        
        //SCALE_NORMAL, SCALE_START0, SCALE_ADDALLSTART0
        $Test->drawScale($data_set->GetData(),$data_set->GetDataDescription(),SCALE_ADDALLSTART0, 150,150,150,TRUE,0,1,TRUE);
             
        $Test->drawGrid(4,TRUE,230,230,230,50);  
        
        // Draw the 0 line  
        $Test->setFontProperties(api_get_path(LIBRARY_PATH).'pchart/fonts/tahoma.ttf',6);  
      //  $Test->drawTreshold(0,143,55,72,TRUE,TRUE);  
        
        // Draw the bar graph  
        $data_set->RemoveSerie("Serie3");  
        
        //$Test->drawBarGraph($data_set->GetData(),$data_set->GetDataDescription(),TRUE);
        
        //$Test->drawStackedBarGraph($data_set->GetData(),$data_set->GetDataDescription(),TRUE);
        $Test->drawOverlayBarGraph($data_set->GetData(),$data_set->GetDataDescription(), 100);  
        
        
        // Finish the graph  
        $Test->setFontProperties(api_get_path(LIBRARY_PATH).'pchart/fonts/tahoma.ttf',8);   
        $Test->drawLegend($main_width - 120,$main_height -100,$data_set->GetDataDescription(),255,255,255);  
        $Test->setFontProperties(api_get_path(LIBRARY_PATH).'pchart/fonts/tahoma.ttf',8); 
        $Test->drawTitle(180,22,$exercise_title,50,50,50);
        $graph_id = 'exercise_result_graph'.Security::remove_XSS($_GET['course']).'-'.intval($_GET['session_id']).'-'.api_get_user_id();
        //if ($cache->IsInCache($graph_id, $data_set->GetData())) {            
		if (0) {
			//if we already created the img
			//echo 'in cache';
			$img_file = $cache->GetHash($graph_id,$data_set->GetData());
        } else {
            $cache->WriteToCache($graph_id, $data_set->GetData(), $Test);
            ob_start();
            $Test->Stroke();
            ob_end_clean();            
            $img_file = $cache->GetHash($graph_id, $data_set->GetData());            
        }      
        $html = '<img src="'.api_get_path(WEB_ARCHIVE_PATH).$img_file.'">';	
        return $html;
    }
}

class TrackingCourseLog {

    function count_item_resources() {
        global $session_id;

        $table_item_property = Database :: get_course_table(TABLE_ITEM_PROPERTY);
        $table_user = Database :: get_main_table(TABLE_MAIN_USER);

        $sql = "SELECT count(tool) AS total_number_of_items FROM $table_item_property track_resource, $table_user user" .
                " WHERE track_resource.insert_user_id = user.user_id AND id_session = $session_id ";

        if (isset($_GET['keyword'])) {
            $keyword = Database::escape_string(trim($_GET['keyword']));
            $sql .= " AND (user.username LIKE '%".$keyword."%' OR lastedit_type LIKE '%".$keyword."%' OR tool LIKE '%".$keyword."%')";
        }

        $sql .= " AND tool IN ('document', 'learnpath', 'quiz', 'glossary', 'link', 'course_description', 'announcement', 'thematic', 'thematic_advance', 'thematic_plan')";
        $res = Database::query($sql);
        $obj = Database::fetch_object($res);
        return $obj->total_number_of_items;
    }

    function get_item_resources_data($from, $number_of_items, $column, $direction) {
        global $dateTimeFormatLong, $session_id;

        $table_item_property = Database :: get_course_table(TABLE_ITEM_PROPERTY);
        $table_user = Database :: get_main_table(TABLE_MAIN_USER);
        $table_session = Database :: get_main_table(TABLE_MAIN_SESSION);

        $sql = "SELECT
                     tool as col0,
                    lastedit_type as col1,
                    ref as ref,
                    user.username as col3,
                    insert_date as col5,
                    visibility as col6
                FROM $table_item_property track_resource, $table_user user
                WHERE track_resource.insert_user_id = user.user_id AND id_session = $session_id ";

        if (isset($_GET['keyword'])) {
            $keyword = Database::escape_string(trim($_GET['keyword']));
            $sql .= " AND (user.username LIKE '%".$keyword."%' OR lastedit_type LIKE '%".$keyword."%' OR tool LIKE '%".$keyword."%') ";
        }

        $sql .= " AND tool IN ('document', 'learnpath', 'quiz', 'glossary', 'link', 'course_description', 'announcement', 'thematic', 'thematic_advance', 'thematic_plan')";

        if ($column == 0) { $column = '0'; }
        if ($column != '' && $direction != '') {
            if ($column != 2 && $column != 4) {
                $sql .=    " ORDER BY col$column $direction";
            }
        } else {
            $sql .=    " ORDER BY col5 DESC ";
        }

        $sql .=    " LIMIT $from, $number_of_items ";

        $res = Database::query($sql);
        $resources = array ();
                $thematic_tools = array('thematic', 'thematic_advance', 'thematic_plan');
        while ($row = Database::fetch_array($res)) {
            $ref = $row['ref'];
            $table_name = TrackingCourseLog::get_tool_name_table($row['col0']);
            $table_tool = Database :: get_course_table($table_name['table_name']);

            $id = $table_name['id_tool'];
                        if ($row['col0'] == 'thematic_plan' || $row['col0'] == 'thematic_advance') {
                            $tbl_thematic = Database :: get_course_table(TABLE_THEMATIC);
                            $rs_thematic = Database::query("SELECT thematic_id FROM $table_tool WHERE id=$ref");
                            $row_thematic = Database::fetch_array($rs_thematic);
                            $thematic_id = $row_thematic['thematic_id'];

                            $query = "SELECT session.id, session.name, user.username FROM $tbl_thematic t, $table_session session, $table_user user" .
                        " WHERE t.session_id = session.id AND session.id_coach = user.user_id AND t.id = $thematic_id";

                        } else {
                            $query = "SELECT session.id, session.name, user.username FROM $table_tool tool, $table_session session, $table_user user" .
                        " WHERE tool.session_id = session.id AND session.id_coach = user.user_id AND tool.$id = $ref";
                        }


            $recorset = Database::query($query);

            if (!empty($recorset)) {
                $obj = Database::fetch_object($recorset);

                $name_session = '';
                $coach_name = '';
                if (!empty($obj)) {
                    $name_session = $obj->name;
                    $coach_name = $obj->username;
                }

                $url_tool = api_get_path(WEB_CODE_PATH).$table_name['link_tool'];
                $row[0] = '';
                if ($row['col6'] != 2) {
                                        if (in_array($row['col0'], $thematic_tools)) {

                                            $exp_thematic_tool = explode('_', $row['col0']);
                                            $thematic_tool_title = '';
                                            if (is_array($exp_thematic_tool)) {
                                                foreach ($exp_thematic_tool as $exp) {
                                                    $thematic_tool_title .= api_ucfirst($exp);
                                                }
                                            } else {
                                                $thematic_tool_title = api_ucfirst($row['col0']);
                                            }

                                            $row[0] = '<a href="'.$url_tool.'?'.api_get_cidreq().'&action=thematic_details">'.get_lang($thematic_tool_title).'</a>';
                                        } else {
                                            $row[0] = '<a href="'.$url_tool.'?'.api_get_cidreq().'&'.$obj->id.'">'.get_lang('Tool'.api_ucfirst($row['col0'])).'</a>';
                                        }
                } else {
                    $row[0] = api_ucfirst($row['col0']);
                }
                $row[1] = get_lang($row[1]);
                $row[5] = api_convert_and_format_date($row['col5'], null, date_default_timezone_get());

                $row[4] = '';
                switch ($table_name['table_name']) {
                    case 'document' :
                        $query_document = "SELECT tool.title as title FROM $table_tool tool" .
                                            " WHERE id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->title;
                    break;
                    case 'announcement':
                        $query_document = "SELECT title FROM $table_tool " .
                                            " WHERE id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->title;
                    break;
                    case 'glossary':
                        $query_document = "SELECT name FROM $table_tool " .
                                                " WHERE glossary_id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->name;
                    break;
                    case 'lp':
                        $query_document = "SELECT name FROM $table_tool " .
                                                " WHERE id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->name;
                    break;
                    case 'quiz':
                        $query_document = "SELECT title FROM $table_tool " .
                                                " WHERE id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->title;
                    break;

                    case 'course_description':
                        $query_document = "SELECT title FROM $table_tool " .
                                                " WHERE id = $ref";
                        $rs_document = Database::query($query_document);
                        $obj_document = Database::fetch_object($rs_document);
                        $row[4] = $obj_document->title;
                    break;

                                        case 'thematic':
                                                $rs = Database::query("SELECT title FROM $table_tool WHERE id = $ref");
                                                if (Database::num_rows($rs) > 0) {
                                                    $obj = Database::fetch_object($rs);
                                                    $row[4] = $obj->title;
                                                }
                                                break;
                                        case 'thematic_advance':
                                                $rs = Database::query("SELECT content FROM $table_tool WHERE id = $ref");
                                                if (Database::num_rows($rs) > 0) {
                                                    $obj = Database::fetch_object($rs);
                                                    $row[4] = $obj->content;
                                                }
                                                break;
                                        case 'thematic_plan':
                                                $rs = Database::query("SELECT title FROM $table_tool WHERE id = $ref");
                                                if (Database::num_rows($rs) > 0) {
                                                    $obj = Database::fetch_object($rs);
                                                    $row[4] = $obj->title;
                                                }
                                                break;

                    default:
                    break;
                }

                $row2 = $name_session;
                if (!empty($coach_name)) {
                    $row2 .= '<br />'.get_lang('Coach').': '.$coach_name;
                }
                $row[2] = $row2;

                $resources[] = $row;
            }
        }

        return $resources;
    }

    function get_tool_name_table($tool) {
        switch ($tool) {
            case 'document':
                $table_name = TABLE_DOCUMENT;
                $link_tool = 'document/document.php';
                $id_tool = 'id';
                break;
            case 'learnpath':
                $table_name = TABLE_LP_MAIN;
                $link_tool = 'newscorm/lp_controller.php';
                $id_tool = 'id';
                break;
            case 'quiz':
                $table_name = TABLE_QUIZ_TEST;
                $link_tool = 'exercice/exercice.php';
                $id_tool = 'id';
                break;
            case 'glossary':
                $table_name = TABLE_GLOSSARY;
                $link_tool = 'glossary/index.php';
                $id_tool = 'glossary_id';
                break;
            case 'link':
                $table_name = TABLE_LINK;
                $link_tool = 'link/link.php';
                $id_tool = 'id';
                break;
            case 'course_description':
                $table_name = TABLE_COURSE_DESCRIPTION;
                $link_tool = 'course_description/';
                $id_tool = 'id';
                break;
            case 'announcement':
                $table_name = TABLE_ANNOUNCEMENT;
                $link_tool = 'announcements/announcements.php';
                $id_tool = 'id';
                break;
                        case 'thematic':
                $table_name = TABLE_THEMATIC;
                $link_tool = 'course_progress/index.php';
                $id_tool = 'id';
                break;
                        case 'thematic_advance':
                $table_name = TABLE_THEMATIC_ADVANCE;
                $link_tool = 'course_progress/index.php';
                $id_tool = 'id';
                break;
                        case 'thematic_plan':
                $table_name = TABLE_THEMATIC_PLAN;
                $link_tool = 'course_progress/index.php';
                $id_tool = 'id';
                break;
            default:
                $table_name = $tool;
                break;
        }
        return array('table_name' => $table_name,'link_tool' => $link_tool,'id_tool' => $id_tool);
    }

    function display_additional_profile_fields() {
        // getting all the extra profile fields that are defined by the platform administrator
        $extra_fields = UserManager :: get_extra_fields(0,50,5,'ASC');

        // creating the form
        $return = '<form action="courseLog.php" method="get" name="additional_profile_field_form" id="additional_profile_field_form">';

        // the select field with the additional user profile fields (= this is where we select the field of which we want to see
        // the information the users have entered or selected.
        $return .= '<select name="additional_profile_field">';
        $return .= '<option value="-">'.get_lang('SelectFieldToAdd').'</option>';

        foreach ($extra_fields as $key=>$field) {
            // show only extra fields that are visible, added by J.Montoya
            if ($field[6]==1) {
                if ($field[0] == $_GET['additional_profile_field'] ) {
                    $selected = 'selected="selected"';
                } else {
                    $selected = '';
                }
                $return .= '<option value="'.$field[0].'" '.$selected.'>'.$field[3].'</option>';
            }
        }
        $return .= '</select>';

        // the form elements for the $_GET parameters (because the form is passed through GET
        foreach ($_GET as $key=>$value){
            if ($key <> 'additional_profile_field')    {
                $return .= '<input type="hidden" name="'.Security::remove_XSS($key).'" value="'.Security::remove_XSS($value).'" />';
            }
        }
        // the submit button
        $return .= '<button class="save" type="submit">'.get_lang('AddAdditionalProfileField').'</button>';
        $return .= '</form>';
        return $return;
    }

    /**
     * This function gets all the information of a certrain ($field_id) additional profile field.
     * It gets the information of all the users so that it can be displayed in the sortable table or in the csv or xls export
     *
     * @author Patrick Cool <patrick.cool@UGent.be>, Ghent University, Belgium
     * @since October 2009
     * @version 1.8.7
     */
    function get_addtional_profile_information_of_field($field_id){
        // Database table definition
        $table_user             = Database::get_main_table(TABLE_MAIN_USER);
        $table_user_field_values     = Database::get_main_table(TABLE_MAIN_USER_FIELD_VALUES);

        $sql = "SELECT user.user_id, field.field_value FROM $table_user user, $table_user_field_values field
            WHERE user.user_id = field.user_id
            AND field.field_id='".intval($field_id)."'";
        $result = Database::query($sql);
        while($row = Database::fetch_array($result)) {
            $return[$row['user_id']][] = $row['field_value'];
        }
        return $return;
    }

    /**
     * This function gets all the information of a certrain ($field_id) additional profile field for a specific list of users is more efficent than  get_addtional_profile_information_of_field() function
     * It gets the information of all the users so that it can be displayed in the sortable table or in the csv or xls export
     *
     * @author    Julio Montoya <gugli100@gmail.com>
     * @param    int field id
     * @param    array list of user ids
     * @return    array
     * @since    Nov 2009
     * @version    1.8.6.2
     */
    function get_addtional_profile_information_of_field_by_user($field_id, $users) {
        // Database table definition
        $table_user                 = Database::get_main_table(TABLE_MAIN_USER);
        $table_user_field_values     = Database::get_main_table(TABLE_MAIN_USER_FIELD_VALUES);
        $result_extra_field         = UserManager::get_extra_field_information($field_id);

        if (!empty($users)) {
            if ($result_extra_field['field_type'] == USER_FIELD_TYPE_TAG ) {
                foreach($users as $user_id) {
                    $user_result = UserManager::get_user_tags($user_id, $field_id);
                    $tag_list = array();
                    foreach($user_result as $item) {
                        $tag_list[] = $item['tag'];
                    }
                    $return[$user_id][] = implode(', ',$tag_list);
                }
            } else {
                $new_user_array = array();
                foreach($users as $user_id) {
                    $new_user_array[]= "'".$user_id."'";
                }
                $users = implode(',',$new_user_array);
                //selecting only the necessary information NOT ALL the user list
                $sql = "SELECT user.user_id, field.field_value FROM $table_user user INNER JOIN $table_user_field_values field
                        ON (user.user_id = field.user_id)
                        WHERE field.field_id=".intval($field_id)." AND user.user_id IN ($users)";

                $result = Database::query($sql);
                while($row = Database::fetch_array($result)) {
                    // get option value for field type double select by id
                    if (!empty($row['field_value'])) {
                        if ($result_extra_field['field_type'] == USER_FIELD_TYPE_DOUBLE_SELECT) {
                            $id_double_select = explode(';',$row['field_value']);
                            if (is_array($id_double_select)) {
                                $value1 = $result_extra_field['options'][$id_double_select[0]]['option_value'];
                                $value2 = $result_extra_field['options'][$id_double_select[1]]['option_value'];
                                $row['field_value'] = ($value1.';'.$value2);
                            }
                        }
                    }
                    // get other value from extra field
                    $return[$row['user_id']][] = $row['field_value'];
                }
            }
        }
        return $return;
    }

    /**
     * count the number of students in this course (used for SortableTable)
     * Deprecated
     */
    function count_student_in_course() {
        global $nbStudents;
        return $nbStudents;
    }

    function sort_users($a, $b) {
        return strcmp(trim(api_strtolower($a[$_SESSION['tracking_column']])), trim(api_strtolower($b[$_SESSION['tracking_column']])));
    }

    function sort_users_desc($a, $b) {
        return strcmp( trim(api_strtolower($b[$_SESSION['tracking_column']])), trim(api_strtolower($a[$_SESSION['tracking_column']])));
    }

    /**
     * Get number of users for sortable with pagination
     * @return int
     */
    function get_number_of_users() {
            global $user_ids;
            return count($user_ids);
    }

    /**
     * Get data for users list in sortable with pagination
     * @return array
     */
    function get_user_data($from, $number_of_items, $column, $direction) {

        global $user_ids, $course_code, $additional_user_profile_info, $export_csv, $is_western_name_order, $csv_content, $session_id, $_configuration;


        $course_code = Database::escape_string($course_code);
        $course_info = CourseManager :: get_course_information($course_code);
        $tbl_user      = Database :: get_main_table(TABLE_MAIN_USER);
        $access_url_id = api_get_current_access_url_id();
        $tbl_url_rel_user = Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);

        // get all users data from a course for sortable with limit
        $condition_user = "";
        if (is_array($user_ids)) {
            $condition_user = " WHERE user.user_id IN (".implode(',',$user_ids).") ";
        } else {
            $condition_user = " WHERE user.user_id = '$user_ids' ";
        }

        if ($_configuration['multiple_access_urls']) {
            $url_table = ", ".$tbl_url_rel_user."as url_users";
            $url_condition = " AND user.user_id = url_users.user_id AND access_url_id='$access_url_id'";
        }

        $sql = "SELECT user.user_id as col0,
                user.official_code as col1,
                user.lastname as col2,
                user.firstname as col3
                FROM $tbl_user as user $url_table
                $condition_user $url_condition";

        if (!in_array($direction, array('ASC','DESC'))) {
            $direction = 'ASC';
        }

        $column = intval($column);
        $from = intval($from);
        $number_of_items = intval($number_of_items);
        $sql .= " ORDER BY col$column $direction ";
        $sql .= " LIMIT $from,$number_of_items";
        
        $res = Database::query($sql);
        $users = array ();
        $t = time();
           $row = array();
        while ($user = Database::fetch_row($res)) {

            $row[0] = $user[1];
            if ($is_western_name_order) {
                $row[1] = $user[3];
                $row[2] = $user[2];
            } else {
                $row[1] = $user[2];
                $row[2] = $user[3];
            }
            $row[3] = api_time_to_hms(Tracking::get_time_spent_on_the_course($user[0], $course_code, $session_id));

            $avg_student_score = Tracking::get_avg_student_score($user[0], $course_code, array(), $session_id);
            //echo '<b>student '.$user[0].' $avg_student_score:</b> '.$avg_student_score; echo '<br />';
            $avg_student_progress = Tracking::get_avg_student_progress($user[0], $course_code, array(), $session_id);
            if (empty($avg_student_progress)) {$avg_student_progress=0;}
            $row[4] = $avg_student_progress.'%';
            //if (empty($avg_student_score)) {$avg_student_score=0;}
            if(is_numeric($avg_student_score)) {
                $row[5] = $avg_student_score.'%';
            } else {
                $row[5] = $avg_student_score;
            }
            $row[6] = Tracking::count_student_assignments($user[0], $course_code, $session_id);
            $row[7] = Tracking::count_student_messages($user[0], $course_code, $session_id);
            $row[8] = Tracking::get_first_connection_date_on_the_course($user[0], $course_code, $session_id);
            $row[9] = Tracking::get_last_connection_date_on_the_course($user[0], $course_code, $session_id);

            // we need to display an additional profile field
            if (isset($_GET['additional_profile_field']) AND is_numeric($_GET['additional_profile_field'])) {
                if (is_array($additional_user_profile_info[$user[0]])) {
                    $row[10]=implode(', ', $additional_user_profile_info[$user[0]]);
                } else {
                    $row[10]='&nbsp;';
                }
            }
            $row[11] = '<center><a href="../mySpace/myStudents.php?student='.$user[0].'&details=true&course='.$course_code.'&origin=tracking_course&id_session='.$session_id.'"><img src="'.api_get_path(WEB_IMG_PATH).'2rightarrow.gif" border="0" /></a></center>';
            if ($export_csv) {
                $row[8] = strip_tags($row[8]);
                $row[9] = strip_tags($row[9]);
                unset($row[10]);
                unset($row[11]);
                $csv_content[] = $row;
            }
            // store columns in array $users
            $users[] = array($row[0],$row[1],$row[2],$row[3],$row[4],$row[5],$row[6],$row[7],$row[8],$row[9],$row[10],$row[11]);
        }
        return $users;
    }
}

class TrackingUserLog {

    /**
    * Displays the number of logins every month for a specific user in a specific course.
    */
    function display_login_tracking_info($view, $user_id, $course_id, $session_id = 0)
    {
        $MonthsLong = $GLOBALS['MonthsLong'];

        // protected data
        $user_id = intval($user_id);
        $session_id = intval($session_id);
        $course_id = Database::escape_string($course_id);

        $track_access_table = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_ACCESS);
        $tempView = $view;
        if(substr($view,0,1) == '1') {
            $new_view = substr_replace($view,'0',0,1);
            echo "
                <tr>
                    <td valign='top'>
                    <font color='#0000FF'>-&nbsp;&nbsp;&nbsp;</font>" .
                    "<b>".get_lang('LoginsAndAccessTools')."</b>&nbsp;&nbsp;&nbsp;[<a href='".api_get_self()."?uInfo=".$user_id."&view=".Security::remove_XSS($new_view)."'>".get_lang('Close')."</a>]&nbsp;&nbsp;&nbsp;[<a href='userLogCSV.php?".api_get_cidreq()."&uInfo=".Security::remove_XSS($_GET['uInfo'])."&view=10000'>".get_lang('ExportAsCSV')."</a>]
                    </td>
                </tr>
                ";
            echo "<tr><td style='padding-left : 40px;' valign='top'>".get_lang('LoginsDetails')."<br>";

            $sql = "SELECT UNIX_TIMESTAMP(access_date), count(access_date)
                        FROM $track_access_table
                        WHERE access_user_id = '$user_id'
                        AND access_cours_code = '$course_id'
                        AND access_session_id = '$session_id'
                        GROUP BY YEAR(access_date),MONTH(access_date)
                        ORDER BY YEAR(access_date),MONTH(access_date) ASC";

            echo "<tr><td style='padding-left : 40px;padding-right : 40px;'>";
            //$results = getManyResults2Col($sql);
            $results = getManyResults3Col($sql);

            echo "<table cellpadding='2' cellspacing='1' border='0' align=center>";
            echo "<tr>
                    <td class='secLine'>
                    ".get_lang('LoginsTitleMonthColumn')."
                    </td>
                    <td class='secLine'>
                    ".get_lang('LoginsTitleCountColumn')."
                    </td>
                </tr>";
            $total = 0;
            if (is_array($results)) {
                for($j = 0 ; $j < count($results) ; $j++) {
                    echo "<tr>";
                    echo "<td class='content'><a href='logins_details.php?uInfo=".$user_id."&reqdate=".$results[$j][0]."&view=".Security::remove_XSS($view)."'>".$MonthsLong[date('n', $results[$j][0])-1].' '.date('Y', $results[$j][0])."</a></td>";
                    echo "<td valign='top' align='right' class='content'>".$results[$j][1]."</td>";
                    echo"</tr>";
                    $total = $total + $results[$j][1];
                }
                echo "<tr>";
                echo "<td>".get_lang('Total')."</td>";
                echo "<td align='right' class='content'>".$total."</td>";
                echo"</tr>";
            } else {
                echo "<tr>";
                echo "<td colspan='2'><center>".get_lang('NoResult')."</center></td>";
                echo"</tr>";
            }
            echo "</table>";
            echo "</td></tr>";
        } else {
            $new_view = substr_replace($view,'1',0,1);
            echo "
                <tr>
                    <td valign='top'>
                    +<font color='#0000FF'>&nbsp;&nbsp;</font><a href='".api_get_self()."?uInfo=".$user_id."&view=".Security::remove_XSS($new_view)."' class='specialLink'>".get_lang('LoginsAndAccessTools')."</a>
                    </td>
                </tr>
            ";
        }
    }

    /**
    * Displays the exercise results for a specific user in a specific course.
    * @todo remove globals
    */
    function display_exercise_tracking_info($view, $user_id, $course_id)
    {
        global $TABLECOURSE_EXERCICES, $TABLETRACK_EXERCICES, $dateTimeFormatLong;
        if(substr($view,1,1) == '1')
        {
            $new_view = substr_replace($view,'0',1,1);
            echo "<tr>
                    <td valign='top'>
                        <font color='#0000FF'>-&nbsp;&nbsp;&nbsp;</font><b>".get_lang('ExercicesResults')."</b>&nbsp;&nbsp;&nbsp;[<a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."'>".get_lang('Close')."</a>]&nbsp;&nbsp;&nbsp;[<a href='userLogCSV.php?".api_get_cidreq()."&uInfo=".Security::remove_XSS($_GET['uInfo'])."&view=01000'>".get_lang('ExportAsCSV')."</a>]
                    </td>
                </tr>";
            echo "<tr><td style='padding-left : 40px;' valign='top'>".get_lang('ExercicesDetails')."<br />";

            $sql = "SELECT ce.title, te.exe_result , te.exe_weighting, UNIX_TIMESTAMP(te.exe_date)
                FROM $TABLECOURSE_EXERCICES AS ce , $TABLETRACK_EXERCICES AS te
                WHERE te.exe_cours_id = '".Database::escape_string($course_id)."'
                    AND te.exe_user_id = '".Database::escape_string($user_id)."'
                    AND te.exe_exo_id = ce.id
                ORDER BY ce.title ASC, te.exe_date ASC";

            $hpsql = "SELECT te.exe_name, te.exe_result , te.exe_weighting, UNIX_TIMESTAMP(te.exe_date)
                FROM $TBL_TRACK_HOTPOTATOES AS te
                WHERE te.exe_user_id = '".Database::escape_string($user_id)."' AND te.exe_cours_id = '".Database::escape_string($course_id)."'
                ORDER BY te.exe_cours_id ASC, te.exe_date ASC";

            $hpresults = getManyResultsXCol($hpsql, 4);

            $NoTestRes = 0;
            $NoHPTestRes = 0;

            echo "<tr>\n<td style='padding-left : 40px;padding-right : 40px;'>\n";
            $results = getManyResultsXCol($sql, 4);
            echo "<table cellpadding='2' cellspacing='1' border='0' align='center'>\n";
            echo "
                <tr bgcolor='#E6E6E6'>
                    <td>
                    ".get_lang('ExercicesTitleExerciceColumn')."
                    </td>
                    <td>
                    ".get_lang('Date')."
                    </td>
                    <td>
                    ".get_lang('ExercicesTitleScoreColumn')."
                    </td>
                </tr>";

            if (is_array($results)) {
                for($i = 0; $i < sizeof($results); $i++) {
                    $display_date = api_convert_and_format_date($results[$i][3], null, date_default_timezone_get());
                    echo "<tr>\n";
                    echo "<td class='content'>".$results[$i][0]."</td>\n";
                    echo "<td class='content'>".$display_date."</td>\n";
                    echo "<td valign='top' align='right' class='content'>".$results[$i][1]." / ".$results[$i][2]."</td>\n";
                    echo "</tr>\n";
                }
            } else {
                // istvan begin
                $NoTestRes = 1;
            }

            // The Result of Tests
            if(is_array($hpresults)) {
                for($i = 0; $i < sizeof($hpresults); $i++) {
                    $title = GetQuizName($hpresults[$i][0],'');
                    if ($title == '')
                        $title = basename($hpresults[$i][0]);
                    $display_date = api_convert_and_format_date($hpresults[$i][3], null, date_default_timezone_get());
    ?>
                    <tr>
                        <td class="content"><?php echo $title; ?></td>
                        <td class="content" align="center"><?php echo $display_date; ?></td>
                        <td class="content" align="center"><?php echo $hpresults[$i][1]; ?> / <?php echo $hpresults[$i][2]; ?></td>
                    </tr>
    <?php        }
            } else {
                $NoHPTestRes = 1;
            }

            if ($NoTestRes == 1 && $NoHPTestRes == 1) {
                echo "<tr>\n";
                echo "<td colspan='3'><center>".get_lang('NoResult')."</center></td>\n";
                echo "</tr>\n";
            }
            echo "</table>";
            echo "</td>\n</tr>\n";
        } else {
            $new_view = substr_replace($view,'1',1,1);
            echo "
                <tr>
                    <td valign='top'>
                        +<font color='#0000FF'>&nbsp;&nbsp;</font><a href='".api_get_self()."?uInfo=$user_id&view=".$new_view."' class='specialLink'>".get_lang('ExercicesResults')."</a>
                    </td>
                </tr>";
        }
    }

    /**
    * Displays the student publications for a specific user in a specific course.
    * @todo remove globals
    */
    function display_student_publications_tracking_info($view, $user_id, $course_id)
    {
        global $TABLETRACK_UPLOADS, $TABLECOURSE_WORK, $dateTimeFormatLong, $_course;
        if(substr($view,2,1) == '1') {
            $new_view = substr_replace($view,'0',2,1);
            echo "<tr>
                        <td valign='top'>
                        <font color='#0000FF'>-&nbsp;&nbsp;&nbsp;</font><b>".get_lang('WorkUploads')."</b>&nbsp;&nbsp;&nbsp;[<a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."'>".get_lang('Close')."</a>]&nbsp;&nbsp;&nbsp;[<a href='userLogCSV.php?".api_get_cidreq()."&uInfo=".Security::remove_XSS($_GET['uInfo'])."&view=00100'>".get_lang('ExportAsCSV')."</a>]
                        </td>
                </tr>";
            echo "<tr><td style='padding-left : 40px;' valign='top'>".get_lang('WorksDetails')."<br>";
            $sql = "SELECT u.upload_date, w.title, w.author,w.url
                                FROM $TABLETRACK_UPLOADS u , $TABLECOURSE_WORK w
                                WHERE u.upload_work_id = w.id
                                    AND u.upload_user_id = '".Database::escape_string($user_id)."'
                                    AND u.upload_cours_id = '".Database::escape_string($course_id)."'
                                ORDER BY u.upload_date DESC";
            echo "<tr><td style='padding-left : 40px;padding-right : 40px;'>";
            $results = getManyResultsXCol($sql,4);
            echo "<table cellpadding='2' cellspacing='1' border='0' align=center>";
            echo "<tr>
                    <td class='secLine' width='40%'>
                    ".get_lang('WorkTitle')."
                    </td>
                    <td class='secLine' width='30%'>
                    ".get_lang('WorkAuthors')."
                    </td>
                    <td class='secLine' width='30%'>
                    ".get_lang('Date')."
                    </td>
                </tr>";
            if (is_array($results)) {
                for($j = 0 ; $j < count($results) ; $j++) {
                    $pathToFile = api_get_path(WEB_COURSE_PATH).$_course['path']."/".$results[$j][3];
                    $beautifulDate = api_convert_and_format_date($results[$j][0], null, date_default_timezone_get());
                    echo "<tr>";
                    echo "<td class='content'>"
                            ."<a href ='".$pathToFile."'>".$results[$j][1]."</a>"
                            ."</td>";
                    echo "<td class='content'>".$results[$j][2]."</td>";
                    echo "<td class='content'>".$beautifulDate."</td>";
                    echo"</tr>";
                }
            } else {
                echo "<tr>";
                echo "<td colspan='3'><center>".get_lang('NoResult')."</center></td>";
                echo"</tr>";
            }
            echo "</table>";
            echo "</td></tr>";
        } else {
            $new_view = substr_replace($view,'1',2,1);
            echo "
                <tr>
                        <td valign='top'>
                        +<font color='#0000FF'>&nbsp;&nbsp;</font><a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."' class='specialLink'>".get_lang('WorkUploads')."</a>
                        </td>
                </tr>
            ";
        }
    }

    /**
    * Displays the links followed for a specific user in a specific course.
    * @todo remove globals
    */
    function display_links_tracking_info($view, $user_id, $course_id)
    {
        global $TABLETRACK_LINKS, $TABLECOURSE_LINKS;
        if(substr($view,3,1) == '1') {
            $new_view = substr_replace($view,'0',3,1);
            echo "
                <tr>
                        <td valign='top'>
                        <font color='#0000FF'>-&nbsp;&nbsp;&nbsp;</font><b>".get_lang('LinksAccess')."</b>&nbsp;&nbsp;&nbsp;[<a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."'>".get_lang('Close')."</a>]&nbsp;&nbsp;&nbsp;[<a href='userLogCSV.php?".api_get_cidreq()."&uInfo=".Security::remove_XSS($_GET['uInfo'])."&view=00010'>".get_lang('ExportAsCSV')."</a>]
                        </td>
                </tr>
            ";
            echo "<tr><td style='padding-left : 40px;' valign='top'>".get_lang('LinksDetails')."<br>";
            $sql = "SELECT cl.title, cl.url
                        FROM $TABLETRACK_LINKS AS sl, $TABLECOURSE_LINKS AS cl
                        WHERE sl.links_link_id = cl.id
                            AND sl.links_cours_id = '".Database::escape_string($course_id)."'
                            AND sl.links_user_id = '".Database::escape_string($user_id)."'
                        GROUP BY cl.title, cl.url";
            echo "<tr><td style='padding-left : 40px;padding-right : 40px;'>";
            $results = getManyResults2Col($sql);
            echo "<table cellpadding='2' cellspacing='1' border='0' align=center>";
            echo "<tr>
                    <td class='secLine'>
                    ".get_lang('LinksTitleLinkColumn')."
                    </td>
                </tr>";
            if (is_array($results)) {
                for($j = 0 ; $j < count($results) ; $j++) {
                        echo "<tr>";
                        echo "<td class='content'><a href='".$results[$j][1]."'>".$results[$j][0]."</a></td>";
                        echo"</tr>";
                }
            } else {
                echo "<tr>";
                echo "<td ><center>".get_lang('NoResult')."</center></td>";
                echo"</tr>";
            }
            echo "</table>";
            echo "</td></tr>";
        } else {
            $new_view = substr_replace($view,'1',3,1);
            echo "
                <tr>
                        <td valign='top'>
                        +<font color='#0000FF'>&nbsp;&nbsp;</font><a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."' class='specialLink'>".get_lang('LinksAccess')."</a>
                        </td>
                </tr>
            ";
        }
    }

    /**
    * Displays the documents downloaded for a specific user in a specific course.
    * @param     string    kind of view inside tracking info
    * @param    int        User id
    * @param    string    Course code
    * @param    int        Session id (optional, default = 0)
    * @return     void
    */
    function display_document_tracking_info($view, $user_id, $course_id, $session_id = 0) {

        // protect data
        $user_id     = intval($user_id);
        $course_id     = Database::escape_string($course_id);
        $session_id = intval($session_id);

        $downloads_table = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_DOWNLOADS);
        if(substr($view,4,1) == '1')
        {
            $new_view = substr_replace($view,'0',4,1);
            echo "
                <tr>
                        <td valign='top'>
                        <font color='#0000FF'>-&nbsp;&nbsp;&nbsp;</font><b>".get_lang('DocumentsAccess')."</b>&nbsp;&nbsp;&nbsp;[<a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."'>".get_lang('Close')."</a>]&nbsp;&nbsp;&nbsp;[<a href='userLogCSV.php?".api_get_cidreq()."&uInfo=".Security::remove_XSS($_GET['uInfo'])."&view=00001'>".get_lang('ExportAsCSV')."</a>]
                        </td>
                </tr>
            ";
            echo "<tr><td style='padding-left : 40px;' valign='top'>".get_lang('DocumentsDetails')."<br>";

            $sql = "SELECT down_doc_path
                        FROM $downloads_table
                        WHERE down_cours_id = '".$course_id."'
                            AND down_user_id = '$user_id'
                            AND down_session_id = '$session_id'
                        GROUP BY down_doc_path";

            echo "<tr><td style='padding-left : 40px;padding-right : 40px;'>";
            $results = getManyResults1Col($sql);
            echo "<table cellpadding='2' cellspacing='1' border='0' align='center'>";
            echo "<tr>
                    <td class='secLine'>
                    ".get_lang('DocumentsTitleDocumentColumn')."
                    </td>
                </tr>";
            if (is_array($results)) {
                for($j = 0 ; $j < count($results) ; $j++) {
                        echo "<tr>";
                        echo "<td class='content'>".$results[$j]."</td>";
                        echo"</tr>";
                }
            } else {
                echo "<tr>";
                echo "<td><center>".get_lang('NoResult')."</center></td>";
                echo"</tr>";
            }
            echo "</table>";
            echo "</td></tr>";
        } else {
            $new_view = substr_replace($view,'1',4,1);
            echo "
                <tr>
                        <td valign='top'>
                        +<font color='#0000FF'>&nbsp;&nbsp;</font><a href='".api_get_self()."?uInfo=".Security::remove_XSS($user_id)."&view=".Security::remove_XSS($new_view)."' class='specialLink'>".get_lang('DocumentsAccess')."</a>
                        </td>
                </tr>
            ";
        }
    }
    
    
}

class TrackingUserLogCSV {

    /**
    * Displays the number of logins every month for a specific user in a specific course.
    */
    function display_login_tracking_info($view, $user_id, $course_id, $session_id = 0)
    {
        $MonthsLong = $GLOBALS['MonthsLong'];
        $track_access_table = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_ACCESS);

        // protected data
        $user_id    = intval($user_id);
        $session_id = intval($session_id);
        $course_id  = Database::escape_string($course_id);

        $tempView = $view;
        if(substr($view,0,1) == '1')
        {
            $new_view = substr_replace($view,'0',0,1);
            $title[1]= get_lang('LoginsAndAccessTools').get_lang('LoginsDetails');

            $sql = "SELECT UNIX_TIMESTAMP(access_date), count(access_date)
                        FROM $track_access_table
                        WHERE access_user_id = '$user_id'
                        AND access_cours_code = '".$course_id."'
                        AND access_session_id = '$session_id'
                        GROUP BY YEAR(access_date),MONTH(access_date)
                        ORDER BY YEAR(access_date),MONTH(access_date) ASC";

            //$results = getManyResults2Col($sql);
            $results = getManyResults3Col($sql);

            $title_line= get_lang('LoginsTitleMonthColumn').';'.get_lang('LoginsTitleCountColumn')."\n";
            $line='';
            $total = 0;
            if (is_array($results))
            {
                for($j = 0 ; $j < count($results) ; $j++)
                {
                    $line .= $results[$j][0].';'.$results[$j][1]."\n";
                    $total = $total + $results[$j][1];
                }
            $line .= get_lang('Total').";".$total."\n";
            }
            else
            {
                $line= get_lang('NoResult')."</center></td>";
            }
        }
        else
        {
            $new_view = substr_replace($view,'1',0,1);
        }
        return array($title_line, $line);
    }

    /**
    * Displays the exercise results for a specific user in a specific course.
    * @todo remove globals
    */
    function display_exercise_tracking_info($view, $user_id, $course_id) {
        global $TABLECOURSE_EXERCICES, $TABLETRACK_EXERCICES, $TABLETRACK_HOTPOTATOES, $dateTimeFormatLong;
        if (substr($view,1,1) == '1') {
            $new_view = substr_replace($view,'0',1,1);

            $title[1]= get_lang('ExercicesDetails');
            $line='';

            $sql = "SELECT ce.title, te.exe_result , te.exe_weighting, UNIX_TIMESTAMP(te.exe_date)
                FROM $TABLECOURSE_EXERCICES AS ce , $TABLETRACK_EXERCICES AS te
                WHERE te.exe_cours_id = '$course_id'
                    AND te.exe_user_id = '$user_id'
                    AND te.exe_exo_id = ce.id
                ORDER BY ce.title ASC, te.exe_date ASC";

            $hpsql = "SELECT te.exe_name, te.exe_result , te.exe_weighting, UNIX_TIMESTAMP(te.exe_date)
                FROM $TABLETRACK_HOTPOTATOES AS te
                WHERE te.exe_user_id = '$user_id' AND te.exe_cours_id = '$course_id'
                ORDER BY te.exe_cours_id ASC, te.exe_date ASC";

            $hpresults = getManyResultsXCol($hpsql, 4);

            $NoTestRes = 0;
            $NoHPTestRes = 0;

            $results = getManyResultsXCol($sql, 4);
            $title_line=get_lang('ExercicesTitleExerciceColumn').";".get_lang('Date').';'.get_lang('ExercicesTitleScoreColumn')."\n";

            if (is_array($results))
            {
                for($i = 0; $i < sizeof($results); $i++)
                {
                    $display_date = api_convert_and_format_date($results[$i][3], null, date_default_timezone_get());
                    $line .= $results[$i][0].";".$display_date.";".$results[$i][1]." / ".$results[$i][2]."\n";
                }
            }
            else // istvan begin
            {
                $NoTestRes = 1;
            }

            // The Result of Tests
            if(is_array($hpresults))
            {
                for($i = 0; $i < sizeof($hpresults); $i++)
                {
                    $title = GetQuizName($hpresults[$i][0],'');

                    if ($title == '')
                        $title = basename($hpresults[$i][0]);

                    $display_date = api_convert_and_format_date($hpresults[$i][3], null, date_default_timezone_get());

                    $line .= $title.';'.$display_date.';'.$hpresults[$i][1].'/'.$hpresults[$i][2]."\n";
                }
            }
            else
            {
                $NoHPTestRes = 1;
            }

            if ($NoTestRes == 1 && $NoHPTestRes == 1)
            {
                $line=get_lang('NoResult');
            }
        }
        else
        {
            $new_view = substr_replace($view,'1',1,1);

        }
        return array($title_line, $line);
    }

    /**
    * Displays the student publications for a specific user in a specific course.
    * @todo remove globals
    */
    function display_student_publications_tracking_info($view, $user_id, $course_id) {
        global $TABLETRACK_UPLOADS, $TABLECOURSE_WORK, $dateTimeFormatLong, $_course;
        if (substr($view,2,1) == '1') {
            $new_view = substr_replace($view,'0',2,1);
            $sql = "SELECT u.upload_date, w.title, w.author, w.url
                    FROM $TABLETRACK_UPLOADS u , $TABLECOURSE_WORK w
                    WHERE u.upload_work_id = w.id
                        AND u.upload_user_id = '$user_id'
                        AND u.upload_cours_id = '$course_id'
                    ORDER BY u.upload_date DESC";
            $results = getManyResultsXCol($sql,4);

            $title[1]=get_lang('WorksDetails');
            $line='';
            $title_line=get_lang('WorkTitle').";".get_lang('WorkAuthors').";".get_lang('Date')."\n";

            if (is_array($results)) {
                for($j = 0 ; $j < count($results) ; $j++) {
                    $pathToFile = api_get_path(WEB_COURSE_PATH).$_course['path']."/".$results[$j][3];
                    $beautifulDate = api_convert_and_format_date($results[$j][0], null, date_default_timezone_get());
                    $line .= $results[$j][1].";".$results[$j][2].";".$beautifulDate."\n";
                }

            } else {
                $line= get_lang('NoResult');
            }
        } else {
            $new_view = substr_replace($view,'1',2,1);
        }
        return array($title_line, $line);
    }

    /**
    * Displays the links followed for a specific user in a specific course.
    * @todo remove globals
    */
    function display_links_tracking_info($view, $user_id, $course_id) {
        global $TABLETRACK_LINKS, $TABLECOURSE_LINKS;
        if (substr($view,3,1) == '1') {
            $new_view = substr_replace($view,'0',3,1);
            $title[1]=get_lang('LinksDetails');
            $sql = "SELECT cl.title, cl.url
                        FROM $TABLETRACK_LINKS AS sl, $TABLECOURSE_LINKS AS cl
                        WHERE sl.links_link_id = cl.id
                            AND sl.links_cours_id = '$course_id'
                            AND sl.links_user_id = '$user_id'
                        GROUP BY cl.title, cl.url";
            $results = getManyResults2Col($sql);
            $title_line= get_lang('LinksTitleLinkColumn')."\n";
            if (is_array($results)) {
                for ($j = 0 ; $j < count($results) ; $j++) {
                        $line .= $results[$j][0]."\n";
                }
            } else {
                $line=get_lang('NoResult');
            }
        } else {
            $new_view = substr_replace($view,'1',3,1);
        }
        return array($title_line, $line);
    }

    /**
    * Displays the documents downloaded for a specific user in a specific course.
    * @param     string    kind of view inside tracking info
    * @param    int        User id
    * @param    string    Course code
    * @param    int        Session id (optional, default = 0)
    * @return     void
    */
    function display_document_tracking_info($view, $user_id, $course_id, $session_id = 0) {
        // protect data
        $user_id     = intval($user_id);
        $course_id     = Database::escape_string($course_id);
        $session_id = intval($session_id);

        $downloads_table = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_DOWNLOADS);

        if (substr($view,4,1) == '1') {
            $new_view = substr_replace($view,'0',4,1);
            $title[1]= get_lang('DocumentsDetails');

            $sql = "SELECT down_doc_path
                        FROM $downloads_table
                        WHERE down_cours_id = '$course_id'
                            AND down_user_id = '$user_id'
                            AND down_session_id = '$session_id'
                        GROUP BY down_doc_path";

            $results = getManyResults1Col($sql);
            $title_line = get_lang('DocumentsTitleDocumentColumn')."\n";
            if (is_array($results)) {
                for ($j = 0 ; $j < count($results) ; $j++) {
                        $line .= $results[$j]."\n";
                }
            } else {
                $line = get_lang('NoResult');
            }
        } else {
            $new_view = substr_replace($view,'1',4,1);
        }
        return array($title_line, $line);
    }
    
    
}