<?php
# Copyright 2001-2006 by VIKO team and contributors
# 
# This file is part of VIKO.
#
# VIKO is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# VIKO is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with VIKO; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

function longtime ($timestamp) {
// Returns long date with date, month, year, hours and minutes
    return date("d.m.Y H:i", return_timestamp($timestamp));
}

function shorttime ($timestamp) {
// Returns short date with day, month and year
    return date("d.m.Y", return_timestamp($timestamp));
}

function date_time ($timestamp) {
// Returns day, month, hours and minutes
    return date("d.m H:i", return_timestamp($timestamp));
}

function date_only ($timestamp) {
// Returns only day and month
    return date("d.m", return_timestamp($timestamp));
}

function return_timestamp ($time) {
// Converts old MySQL timestamp to MySQL 4.1 timestamp
// Converts MySQL 4.1 timestamp to UNIX timestamp
	if(is_numeric($time) && strlen($time)==14) {
		$time = substr($time, 0, 4)."-".substr($time, 4, 2)."-".substr($time, 6, 2)." ".substr($time, 8, 2).":".substr($time, 10, 2).":".substr($time, 12, 2);
	}
	$time = strtotime($time);
    return $time;
}

function log_views ($course_id, $userid) {
    $result = mysql_query("SELECT * FROM Courses_Users WHERE
    course_id='$course_id' && user_id='$userid'");
    $total_views = 0;
    while($row = mysql_fetch_array($result)){
        $total_views = $row["total_views"];
        }

    $total_views = ++$total_views;

    $result = mysql_query("UPDATE Courses_Users SET
        total_views = '$total_views'
    WHERE course_id='$course_id' && user_id='$userid'");
}

function return_course_description($course_id) {
    $result = mysql_query("SELECT * FROM Courses WHERE course_id='$course_id'");
    while($row = mysql_fetch_array($result)){
        $description = $row["description"];
        }
    return $description;
}

function return_course_name($course_id) {
    $result = mysql_query("SELECT * FROM Courses WHERE course_id='$course_id'");
    while($row = mysql_fetch_array($result)){
        $name = $row["name"];
        }
    return $name;
}

function return_user_name($user_id) {
    $result = mysql_query("SELECT firstname,lastname FROM Users WHERE user_id='$user_id'");
    while($row = mysql_fetch_array($result)){
        $firstname = $row["firstname"];
        $lastname = $row["lastname"];
        }
    $fullname = $firstname." ".$lastname;
    return $fullname;
}

function return_marktype($course_id, $lesson_num) {
    $result = mysql_query("SELECT * FROM Lessons WHERE course_id='$course_id' &&
        lesson_num='$lesson_num'");
    while($row = mysql_fetch_array($result)){
        $marktype = $row["marktype"];
        }
    return $marktype;
}

function strip_all_tags ($text) {
    $text = strip_tags($text);
    $text = addslashes($text);
    return $text;
}

function is_email($email) {
    if((!ereg(".+\@.+\..+", $email)) || (!ereg("^[a-zA-Z0-9_@.-]+$", $email)) || ($email=="")) {
        return false;
        }
    else {
        return true;
    }
}

function current_day ($day) {
    $current_day = date("j");
    if($day==$current_day) {
        print(" selected=\"selected\"");
    }
}

function current_month ($month) {
    $current_month = date("n");
    if($month==$current_month) {
        print(" selected=\"selected\"");
    }
}

function current_year () {
    $current_year = date("Y");
    return $current_year;
    }

function num_of_schools () {
	$result = mysql_query("SELECT school_id FROM Schools");
	$num = mysql_numrows($result);
	return $num;
}

function num_of_active_schools () {
	$num = 0;
	$result = mysql_query("SELECT school_id FROM Schools");
	while($row = mysql_fetch_array($result)) {
		$school_id = $row["school_id"];

		if(num_of_students($school_id) >= 10) {
			$num++;
		}
	}
	return $num;
}

function num_of_users ($school_id) {
    $result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_students ($school_id) {
    $result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level=0");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_teachers ($school_id) {
    $result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level>0");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_forms ($school_id) {
    $result = mysql_query("SELECT form_number FROM Forms WHERE school_id='$school_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_courses ($school_id) {
	$num_total = 0;
	$result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level>0");
	while($row = mysql_fetch_array($result)) {
		$user_id = $row["user_id"];
		$result_courses = mysql_query("SELECT course_id FROM Courses WHERE teacher='$user_id'");
		$num = mysql_numrows($result_courses);
		$num_total = $num_total + $num;
	}
	return $num_total;
}

function size_of_files ($school_id) {
	$filesize_total = 0;
	$result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level>0");
	while($row = mysql_fetch_array($result)){
		$user_id = $row["user_id"];
		$result_files = mysql_query("SELECT filesize FROM Files WHERE user_id='$user_id'");
		while($row = mysql_fetch_array($result_files)){
			$filesize = $row["filesize"];
			$filesize_total = $filesize_total + $filesize;
		}
	}
	return $filesize_total;
}

function num_of_students_in_course ($course_id) {
    $result = mysql_query("SELECT user_id FROM Courses_Users WHERE course_id='$course_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_files_in_course ($course_id) {
    $result = mysql_query("SELECT file_id FROM Files WHERE course_id='$course_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_links_in_course ($course_id) {
    $result = mysql_query("SELECT link_id FROM Links WHERE course_id='$course_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_messages_in_course ($course_id) {
    $result = mysql_query("SELECT message_id FROM Messages WHERE course_id='$course_id'");
    $num = mysql_numrows($result);
    return $num;
}

function num_of_marks_in_course ($course_id) {
    $result = mysql_query("SELECT mark FROM Marks WHERE course_id='$course_id'");
    $num = mysql_numrows($result);
    return $num;
}

function total_views_in_course ($course_id) {
	$result = mysql_query("SELECT total_views FROM Courses_Users WHERE course_id='$course_id'");
	if(mysql_num_rows($result)>0) {
		$course_total_views = 0;
		while($row = mysql_fetch_array($result)) {
			$total_views = $row["total_views"];
			$course_total_views = $course_total_views + $total_views;
		}
	}
	else {
		$course_total_views = 0;
	}
	return $course_total_views;
}

function student_num_of_courses ($student_id) {
    $result = mysql_query("SELECT course_id FROM Courses_Users WHERE user_id='$student_id'");
    $num = mysql_numrows($result);
    return $num;
}

function delete_student ($student_id) {
    $result = mysql_query("DELETE FROM Marks WHERE user_id='$student_id'");
    $result = mysql_query("DELETE FROM Messages WHERE user_id='$student_id'");
    $result = mysql_query("DELETE FROM Topics WHERE user_id='$student_id'");
    $result = mysql_query("DELETE FROM Links WHERE user_id='$student_id'");
    $result = mysql_query("DELETE FROM Courses_Users WHERE user_id='$student_id'");
    $result = mysql_query("DELETE FROM Users WHERE user_id='$student_id' AND level='0'");
}

function delete_course ($course_id) {
    $result = mysql_query("DELETE FROM Messages WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Topics WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Links WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Links_Folders WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Marks WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Lessons WHERE course_id='$course_id'");
    $result = mysql_query("SELECT file_id FROM Files WHERE course_id='$course_id'");
    while($row = mysql_fetch_array($result)){
        $file_id = $row["file_id"];
        delete_file($file_id);
    }
    $result = mysql_query("DELETE FROM Files WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Files_Folders WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Courses_Users WHERE course_id='$course_id'");
    $result = mysql_query("DELETE FROM Courses WHERE course_id='$course_id'");
}

function delete_file($file_id) {
    $result = mysql_query("DELETE FROM Files WHERE file_id='$file_id'");
    $dir="../files/$file_id";
    $current_dir = opendir($dir);
    while($entryname = readdir($current_dir)){
      if(is_dir("$dir/$entryname") and ($entryname != "." and $entryname!="..")){
          deldir("${dir}/${entryname}");
      }elseif($entryname != "." and $entryname!=".."){
          unlink("${dir}/${entryname}");
      }
    }
    closedir($current_dir);
    rmdir(${dir});
}

function delete_file_folder($folder_id) {
    $result = mysql_query("SELECT file_id FROM Files WHERE folder_id='$folder_id'");
    while($row = mysql_fetch_array($result)){
        $file_id = $row["file_id"];
        delete_file($file_id);
    }
    $result = mysql_query("DELETE FROM Files_Folders WHERE folder_id='$folder_id'");
}

function delete_teacher($teacher_id) {
    $result = mysql_query("SELECT course_id FROM Courses WHERE teacher='$teacher_id'");
    while($row = mysql_fetch_array($result)){
        $course_id = $row["course_id"];
        delete_course($course_id);
    }
    $result = mysql_query("DELETE FROM Users WHERE user_id='$teacher_id' AND level='1'");
}

function delete_school($school_id) {
    $result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level>0");
    while($row = mysql_fetch_array($result)){
        $user_id = $row["user_id"];
        delete_teacher($user_id);
    }
    $result = mysql_query("SELECT user_id FROM Users WHERE school_id='$school_id' && level=0");
    while($row = mysql_fetch_array($result)){
        $user_id = $row["user_id"];
        delete_student($user_id);
    }
    $result = mysql_query("DELETE FROM Forms WHERE school_id='$school_id'");
    $result = mysql_query("DELETE FROM Schools WHERE school_id='$school_id'");
}

function rename_uploaded_file ($uploaded_filename) {

	//Replace non-alphanumeric characters
	$length = strlen($uploaded_filename);
	$new_filename = "";
	$i = 0;
	while ($i < $length) {
		$char = $uploaded_filename{$i};
		if(!ctype_alnum($char)) {
			$ascii = ord($char);
			switch ($ascii) {
				case 40:
					$newchar = "(";
					break;
				case 41:
					$newchar = ")";
					break;
				case 45:
					$newchar = "-";
					break;
				case 32:
				case 95:
					$newchar = "_";
					break;
				case 46:
					$newchar = ".";
					break;				case 192:
				case 193:
				case 194:
				case 195:
				case 196:
				case 197:
				case 198:
					$newchar = "A";
					break;
				case 210:
				case 211:
				case 212:
				case 213:
				case 214:
					$newchar = "O";
					break;
				case 217:
				case 218:
				case 219:
				case 220:
				case 221:
					$newchar = "Y";
					break;
				case 224:
				case 225:
				case 226:
				case 227:
				case 228:
				case 229:
				case 230:
					$newchar = "a";
					break;
				case 242:
				case 243:
				case 244:
				case 245:
				case 246:
					$newchar = "o";
					break;
				case 249:
				case 250:
				case 251:
				case 252:
				case 253:
					$newchar = "y";
					break;
				default:
					$newchar = "";
			}
			$new_filename = $new_filename.$newchar;
		}
		else {
			$new_filename = $new_filename.$char;	
		}
		$i++;
	}
	
	//Replace double underscores
	while(strpos($new_filename, "__")) {
		$new_filename=str_replace("__","_",$new_filename);
	}
	
	//Change file extension to lowercase
	$dot_position = strpos($new_filename, ".");
	$filename = substr($new_filename, 0, $dot_position);
	$extensions = strtolower(substr($new_filename, $dot_position));
	$new_filename = $filename.$extensions;
	
	//Change file extensions
	$new_filename=str_replace(".php",".txt",$new_filename);
	$new_filename=str_replace(".php3",".txt",$new_filename);
	$new_filename=str_replace(".php4",".txt",$new_filename);
	$new_filename=str_replace(".cgi",".txt",$new_filename);
	$new_filename=str_replace(".pl",".txt",$new_filename);
	$new_filename=str_replace(".phtml",".txt",$new_filename);
	$new_filename=str_replace(".shtml",".txt",$new_filename);
	
	return $new_filename;
}

?>