main_api.lib.php

完美的在线教育系统

* false otherwise.
*/
function api_is_allowed_to_create_course()
{
	return $_SESSION["is_allowedCreateCourse"];
}
/**
 * Check if the current user is a course administrator
 * @return boolean True if current user is a course administrator
 */
function api_is_course_admin()
{
	return $_SESSION["is_courseAdmin"];
}
/**
 * Check if the current user is a course coach
 * @return	bool	True if current user is a course coach
 */
function api_is_course_coach()
{
	return $_SESSION['is_courseCoach'];
}
/**
 * Check if the current user is a course tutor
 * @return 	bool	True if current user is a course tutor
 */
function api_is_course_tutor()
{
	return $_SESSION['is_courseTutor'];
}
/**
 * Check if the current user is a course or session coach
 * @return boolean True if current user is a course or session coach
 */
function api_is_coach()
{
	global $_user;
	global $sessionIsCoach;

	$sql = "SELECT DISTINCT id, name, date_start, date_end
							FROM session
							INNER JOIN session_rel_course
								ON session_rel_course.id_coach = '".mysql_real_escape_string($_user['user_id'])."'
							ORDER BY date_start, date_end, name";
	$result = api_sql_query($sql,__FILE__,__LINE__);
	$sessionIsCoach = api_store_result($result);

	$sql = "SELECT DISTINCT id, name, date_start, date_end
							FROM session
							WHERE session.id_coach =  '".mysql_real_escape_string($_user['user_id'])."'
							ORDER BY date_start, date_end, name";
	$result = api_sql_query($sql,__FILE__,__LINE__);
	$sessionIsCoach = array_merge($sessionIsCoach , api_store_result($result));

	if(count($sessionIsCoach) > 0)
	{
		return true;
	}
	else
	{
		return false;
	}
}
/*
==============================================================================
		DISPLAY OPTIONS
		student view, title, message boxes,...
==============================================================================
*/
/**
 * Displays the title of a tool.
 * Normal use: parameter is a string:
 * api_display_tool_title("My Tool")
 *
 * Optionally, there can be a subtitle below
 * the normal title, and / or a supra title above the normal title.
 *
 * e.g. supra title:
 * group
 * GROUP PROPERTIES
 *
 * e.g. subtitle:
 * AGENDA
 * calender & events tool
 *
 * @author Hugues Peeters <[e-mail]>
 * @param  mixed $titleElement - it could either be a string or an array
 *                               containing 'supraTitle', 'mainTitle',
 *                               'subTitle'
 * @return void
 */
function api_display_tool_title($titleElement)
{
	if (is_string($titleElement))
	{
		$tit = $titleElement;
		unset ($titleElement);
		$titleElement['mainTitle'] = $tit;
	}
	echo '<h3>';
	if (!empty($titleElement['supraTitle']))
	{
		echo '<small>'.$titleElement['supraTitle'].'</small><br>';
	}
	if (!empty($titleElement['mainTitle']))
	{
		echo $titleElement['mainTitle'];
	}
	if (!empty($titleElement['subTitle']))
	{
		echo '<br><small>'.$titleElement['subTitle'].'</small>';
	}
	echo '</h3>';
}
/**
*	Display options to switch between student view and course manager view
*
*	Changes in version 1.2 (Patrick Cool)
*	Student view switch now behaves as a real switch. It maintains its current state until the state
*	is changed explicitly
*
*	Changes in version 1.1 (Patrick Cool)
*	student view now works correctly in subfolders of the document tool
*	student view works correctly in the new links tool
*
*	Example code for using this in your tools:
*	//if ( $is_courseAdmin && api_get_setting('student_view_enabled') == 'true' )
*	//{
*	//	display_tool_view_option($isStudentView);
*	//}
*	//and in later sections, use api_is_allowed_to_edit()
*
	@author Roan Embrechts
*	@author Patrick Cool
*	@version 1.2
*	@todo rewrite code so it is easier to understand
*/
function api_display_tool_view_option()
{
	if (api_get_setting('student_view_enabled') != "true")
	{
		return '';
	}
	$output_string='';

	$sourceurl = '';
	$is_framed = false;
	// Exceptions apply for all multi-frames pages
	if (strpos($_SERVER['REQUEST_URI'],'chat/chat_banner.php')!==false)
	{	//the chat is a multiframe bit that doesn't work too well with the student_view, so do not show the link
		$is_framed = true;
		return '';
	}
	// Uncomment to remove student view link from document view page
	if(strpos($_SERVER['REQUEST_URI'],'document/headerpage.php')!==false)
	{
		$sourceurl = str_replace('document/headerpage.php','document/showinframes.php',$_SERVER['REQUEST_URI']);
		//showinframes doesn't handle student view anyway...
		//return '';
		$is_framed = true;
	}
    // Uncomment to remove student view link from document view page
    if(strpos($_SERVER['REQUEST_URI'],'newscorm/lp_header.php')!==false)
    {
    	if(empty($_GET['lp_id']))
        {
        	return '';
        }
        $sourceurl = substr($_SERVER['REQUEST_URI'],0,strpos($_SERVER['REQUEST_URI'],'?'));
        $sourceurl = str_replace('newscorm/lp_header.php','newscorm/lp_controller.php?'.api_get_cidreq().'&action=view&lp_id='.intval($_GET['lp_id']).'&isStudentView='.($_SESSION['studentview']=='studentview'?'false':'true'),$sourceurl);
        //showinframes doesn't handle student view anyway...
        //return '';
        $is_framed = true;
    }

	// check if the $_SERVER['REQUEST_URI'] contains already url parameters (thus a questionmark)
	if(!$is_framed)
	{
		if (!strstr($_SERVER['REQUEST_URI'], "?"))
		{
			$sourceurl = api_get_self()."?".api_get_cidreq();
		}
		else
		{
			$sourceurl = $_SERVER['REQUEST_URI'];
			//$sourceurl = str_replace('&', '&amp;', $sourceurl);
		}
	}
	if(!empty($_SESSION['studentview']))
	{
		if ($_SESSION['studentview']=='studentview')
		{
			// we have to remove the isStudentView=true from the $sourceurl
			$sourceurl = str_replace('&isStudentView=true', '', $sourceurl);
			$sourceurl = str_replace('&isStudentView=false', '', $sourceurl);
			$output_string .= '<a href="'.$sourceurl.'&isStudentView=false" target="_top">'.get_lang("CourseManagerview").'</a>';
		}
		elseif ($_SESSION['studentview']=='teacherview')
		{
			//switching to teacherview
			$sourceurl = str_replace('&isStudentView=true', '', $sourceurl);
			$sourceurl = str_replace('&isStudentView=false', '', $sourceurl);
			$output_string .= '<a href="'.$sourceurl.'&isStudentView=true" target="_top">'.get_lang("StudentView").'</a>';
		}
	}
	else
	{
		$output_string .= '<a href="'.$sourceurl.'&isStudentView=true" target="_top">'.get_lang("StudentView").'</a>';
	}
	echo $output_string;
}
/**
 * Displays the contents of an array in a messagebox.
 * @param array $info_array An array with the messages to show
 */
function api_display_array($info_array)
{
	foreach ($info_array as $element)
	{
		$message .= $element."<br>";
	}
	Display :: display_normal_message($message);
}
/**
*	Displays debug info
* @param string $debug_info The message to display
*	@author Roan Embrechts
*	@version 1.1, March 2004
*/
function api_display_debug_info($debug_info)
{
	$message = "<i>Debug info</i><br>";
	$message .= $debug_info;
	Display :: display_normal_message($message);
}
/**
*	@deprecated, use api_is_allowed_to_edit() instead
*/
function is_allowed_to_edit()
{
	return api_is_allowed_to_edit();
}

/**
*	Function that removes the need to directly use is_courseAdmin global in
*	tool scripts. It returns true or false depending on the user's rights in
*	this particular course.
*	Optionally checking for tutor and coach roles here allows us to use the
*	student_view feature altogether with these roles as well.
*	@param	bool	Whether to check if the user has the tutor role
*	@param	bool	Whether to check if the user has the coach role
*
*	@author Roan Embrechts
*	@author Patrick Cool
*	@version 1.1, February 2004
*	@return boolean, true: the user has the rights to edit, false: he does not
*/
function api_is_allowed_to_edit($tutor=false,$coach=false)
{
	$is_courseAdmin = api_is_course_admin() || api_is_platform_admin();
	if(!$is_courseAdmin && $tutor == true)
	{	//if we also want to check if the user is a tutor...
		$is_courseAdmin = $is_courseAdmin || api_is_course_tutor();
	}
	if(!$is_courseAdmin && $coach == true)
	{	//if we also want to check if the user is a coach...
		$is_courseAdmin = $is_courseAdmin || api_is_course_coach();
	}	
	if(api_get_setting('student_view_enabled') == 'true')
	{	//check if the student_view is enabled, and if so, if it is activated
		$is_allowed = $is_courseAdmin && $_SESSION['studentview'] != "studentview";
		return $is_allowed;
	}
	else
		return $is_courseAdmin;
}

/**
* this fun
* @param $tool the tool we are checking ifthe user has a certain permission
* @param $action the action we are checking (add, edit, delete, move, visibility)
* @author Patrick Cool <[e-mail]>, Ghent University
* @version 1.0
*/
function api_is_allowed($tool, $action, $task_id = 0)
{
	global $_course;
	global $_user;

	if(api_is_course_admin())
		return true;

	//if(!$_SESSION['total_permissions'][$_course['code']] and $_course)
	if($_course)
	{
		require_once(api_get_path(SYS_CODE_PATH) . 'permissions/permissions_functions.inc.php');
		require_once(api_get_path(LIBRARY_PATH) . "/groupmanager.lib.php");

		// getting the permissions of this user
		if($task_id == 0)
		{
			$user_permissions = get_permissions('user', $_user['user_id']);
			$_SESSION['total_permissions'][$_course['code']] = $user_permissions;
		}

		// getting the permissions of the task
		if($task_id != 0)
		{
			$task_permissions = get_permissions('task', $task_id);
			/* !!! */$_SESSION['total_permissions'][$_course['code']] = $task_permissions;
		}
		//print_r($_SESSION['total_permissions']);

		// getting the permissions of the groups of the user
		//$groups_of_user = GroupManager::get_group_ids($_course['db_name'], $_user['user_id']);

		//foreach($groups_of_user as $group)
			//$this_group_permissions = get_permissions('group', $group);

		// getting the permissions of the courseroles of the user
		$user_courserole_permissions = get_roles_permissions('user', $_user['user_id']);

		// getting the permissions of the platformroles of the user
		//$user_platformrole_permissions = get_roles_permissions('user', $_user['user_id'], ', platform');

		// getting the permissions of the roles of the groups of the user
		//foreach($groups_of_user as $group)
			//$this_group_courserole_permissions = get_roles_permissions('group', $group);

		// getting the permissions of the platformroles of the groups of the user
		//foreach($groups_of_user as $group)
			//$this_group_platformrole_permissions = get_roles_permissions('group', $group, 'platform');
	}

	// ifthe permissions are limited we have to map the extended ones to the limited ones
	if(api_get_setting('permissions') == 'limited')
	{
		if($action == 'Visibility')
			$action = 'Edit';

		if($action == 'Move')
			$action = 'Edit';
	}

	// the session that contains all the permissions already exists for this course
	// so there is no need to requery everything.
	//my_print_r($_SESSION['total_permissions'][$_course['code']][$tool]);
	if(in_array($action, $_SESSION['total_permissions'][$_course['code']][$tool]))
		return true;
	else
		return false;
}

/**
 * Tells whether this user is an anonymous user
 * @param	int		User ID (optional, will take session ID if not provided)
 * @param	bool	Whether to check in the database (true) or simply in the session (false) to see if the current user is the anonymous user
 * @return	bool	true if this user is anonymous, false otherwise
 */
function api_is_anonymous($user_id=null,$db_check=false)
{
	if(!isset($user_id))
	{
		$user_id = api_get_user_id();
	}
	if($db_check)
	{
		$info = api_get_user_info($user_id);
		if($info['status'] == 6)
		{
			return true;
		}
	}
	else
	{
		global $_user;
		if(!isset($_user)){
			//in some cases, api_set_anonymous doesn't seem to be
			//triggered in local.inc.php. Make sure it is.	
			//Occurs in agenda for admin links - YW
			global $use_anonymous;
                        if(isset($use_anonymous) && $use_anonymous == true)
                        {
                                api_set_anonymous();
                        }
			return true;
		}
		if(isset($_user['is_anonymous']) and $_user['is_anonymous'] === true)
		{
			return true;
		}
	}
	return false;
}

/**
 * Displays message "You are not allowed here..." and exits the entire script.
 * @param	bool	Whether or not to print headers (default = false -> does not print them)
 *
 * @author Roan Embrechts
 * @author Yannick Warnier
 * @author Patrick Cool <[e-mail]>, Ghent University
*
 * @version 1.0, February 2004
 * @version dokeos 1.8, August 2006
*/
function api_not_allowed($print_headers = false)
{
	$home_url = api_get_path(WEB_PATH);
	$user = api_get_user_id();
	$course = api_get_course_id();
	if((isset($user) && !api_is_anonymous()) 
		&& (!isset($course) || $course==-1) 
		&& empty($_GET['cidReq']))
	{//if the access is not authorized and there is some login information 
	 // but the cidReq is not found, assume we are missing course data and send the user