* @copyright 2001-2007 VIKO team and contributors
* @license http://www.gnu.org/licenses/gpl.html GPL 2.0
*/
require_once 'Module.php';
require_once 'Course.php';
/**
* Abstract parent class for all course modules
*
* Each subclass of this module represents the whole functionality
* under one element in the course menu. (The course menu is the menu,
* which appears at the top of the screen, when student or teacher
* selects a course.)
*
* For example if you want to add a image gallery to VIKO, you would
* create a subclass Module_Course_Gallery and save it into file
* lib/Module/Course/Gallery.php
*
* The file itself should contain at least the following:
*
*
* require_once('Module/Course.php');
*
* class Module_Course_Gallery extends Module_Course
* {
* }
*
*
* Well, that's barely enough - so, let's add some implementation too.
*
* First we need to create the constructor, that overrides the constructor
* in the parent class.
*
*
* function Module_Course_Gallery( $course, $parameters )
* {
* // get image number from parameters array,
* // but only when it is specified.
* if isset( $parameters[1] ) {
* $this->_image_nr = $parameters[1];
* }
*
* // pass information on to parent constructor
* parent::Module_Course( $course, $parameters )
* }
*
*
*
* As seen from above, the constructor takes two arguments.
* The first is an instance of Course, which we'll pass on to
* parent class.
*
* The other argument contains parameters specific for this
* module. All the parameters come from the URI, which was used
* to access this course module. URI-s are in the following form:
*
*
* /course-nr/module-name/parameter-1/parameter-2/...
*
*
* This has to be rewritten... but I don't bother to do it now.
*
*
* /**
* * Some special variables for the gallery
* * /
* var $_gallery_nr = 1;
* var $_image_nr = null;
*
* /**
* * Create HTML for the gallery when needed
* * /
* function toHTML()
* {
* }
*
*
*/
class Module_Course extends Module {
/**
* Stores the course object
*
* @access private
* @var Course
*/
var $_course = null;
/**
* Determines weather the menu item is selected or just highlighted.
*
* @access private
* @var string
*/
var $_selected_menu_item_status = 'SELECTED';
/**
* Creates new Course Module
*
* The value of first parameter is stored into _course attribute.
* Nothing is done with the other parameter - the implementation
* is left for child classes.
*
* @param Course $course object representing the currently selected course
* @param array $parameters parameters to the module
*/
function Module_Course( $course, $parameters )
{
$this->_course = $course;
}
/**
* Returns the module identifier string
*
* This method must be implemeneted in derived classes.
*
* @access public
* @static
* @return string Identificator of module
*/
function getID()
{
return "course";
}
/**
* Returns the short name of the module, this is used in navigation menu.
*
* Must be implemented inside subclass
*
* @access public
* @static
* @abstract
* @return string short name
*/
function getName()
{
trigger_error("getName not implemeneted", E_USER_ERROR);
}
/**
* Returns short description of module
*
* This might be used as a title attribute value in navigation.
*
* Must be implemented inside subclass
*
* @access public
* @static
* @abstract
* @return string module description
*/
function getDescription()
{
trigger_error("getDescription not implemeneted", E_USER_ERROR);
}
/**
* Returns the state of currently selected menu item
*
* This can be either 'SELECTED' or 'HIGHLIGHTED'.
* If the menu link is selected, then user can not click it,
* but highlighted link is clickable.
*
* By default this function returnes 'SELECTED', but derived
* classes are probably changing this behavior to suit their needs.
*
* @return string either 'SELECTED' or 'HIGHLIGHTED'
*/
function getSelectedMenuItemStatus()
{
return $this->_selected_menu_item_status;
}
/**
* Returns true if this course module is viewable by student
*
* By default each course module should be listed in the
* course menu of student also. So this method returns true
* by default. But some modules only need to be viewed by
* teachers - those modules can override this method.
*
* @return bool true if is allowed
*/
function studentIsAllowedToView()
{
return true;
}
/**
* Creates URI relative to the current domain
*
* This method should be used when creating relative links inside
* a course module. The method will create URI relative to the
* VIKO install path and consisting of the following parts:
*
*
* VIKO_path / course_id / course_module_id [ / parameter ]*
*
*
* The parameters are the parameters supplied to this method (the method
* takes multiple parameters; preferably strings). Alternatively the
* method may take only one parameter as array.
*
* For example, when using the code below inside Module_Course_Lessons:
*
*
* $this->relativeURI( 'edit', $lesson->getID() );
*
*
* If the selected course has ID 1043, $lesson->getID() returns 128 and
* VIKO is installed to "/", then the created URI will be the following:
*
*
* /1043/lessons/edit/128
*
*
*
* @return string absolute URI
*/
function relativeURI()
{
// get all arguments
$args = func_get_args();
// if the first argument was array,
// use that as the argument list instead
if (isset($args[0]) && is_array($args[0])) {
$args = $args[0];
}
// put the course ID and module name at the beginning of argument list
$args = array_merge(
array( $this->_course->getID() , $this->getID() ),
$args
);
// use URI method to create final path
return $this->URI( $args );
}
/**
* Redirects to another page inside the current course module
*
* Like Module::redirect() takes any number of arguments or
* one argument as array. But only the parameters to the module
* need to be specified, course_id and module name are added
* automatically.
*/
function redirectInsideCourseModule()
{
$args = func_get_args();
// if the first argument was array,
// use that as the argument list instead
if (isset($args[0]) && is_array($args[0])) {
$args = $args[0];
}
// merge module name at the beginning of argument list
$args = array_merge(
array( $this->getID() ),
$args
);
// go to the resulting address
$this->redirectInsideCourse( $args );
}
/**
* Redirects to another page inside the current course
*
* Like Module::redirect() takes any number of arguments
* or one argument as array. But only the name of the module
* and parameters to the module need to be specified,
* course_id is added automatically.
*/
function redirectInsideCourse()
{
$args = func_get_args();
// if the first argument was array,
// use that as the argument list instead
if (isset($args[0]) && is_array($args[0])) {
$args = $args[0];
}
// merge course_id at the beginning of argument list
$args = array_merge(
array( $this->_course->getID() ),
$args
);
// go to the resulting address
$this->redirect( $args );
}
/**
* Checks if user can edit this course or not
*
* e.g. weather user is teacher of this course.
*
* @access protected
* @return bool true if user can edit the course.
*/
function _userCanEditThisCourse()
{
$course_teacher = $this->_course->getTeacher();
return ( $course_teacher->getID() == $_SESSION['user']->getID() );
}
/**
* Creates H2 title for the course page
*
* If page name parameter is not specified, the name of the current
* course module is used instead.
*
* If the user has TEACHER rights for this course, then the course subname
* is also displayd (if, of course, that name exists).
*
* @access protected
* @param string $page_name first part of the H2 title
* @return string H2 title
*/
function title( $page_name=null )
{
// get course name and subname
$course_name = $this->_course->getHTMLName();
$course_subname = $this->_course->getHTMLSubName();
// if page name is not specified, use module name
if ( !isset($page_name) ) {
$page_name = htmlspecialchars( $this->getName() );
}
// title consists of page name and course name
$title = "$page_name: $course_name";
// If the user teacher of this course and course subname is specified,
// then append the course subname to the title (separated with en-dash).
if ( $this->_userCanEditThisCourse() && strlen( $course_subname ) > 0 ) {
$title .= " – $course_subname";
}
return parent::title( $title );
}
}
?>