<?php
/* For licensing terms, see /license.txt */
/**
 *
 *                             SCRIPT PURPOSE
 *
 * This script initializes and manages Chamilo session information. It
 * keeps available session information up to date.
 *
 * You can request a course id. It will check if the course Id requested is the
 * same as the current one. If it isn't it will update session information from
 * the database. You can also force the course reset if you want ($cidReset).
 *
 * All the course information is stored in the $_course array.
 *
 * You can request a group id. The script will check if the group id requested is the
 * same as the current one. If it isn't it will update session information from
 * the database. You can also force the course reset if you want ($gidReset).
 *
 * The course id is stored in $_cid session variable.
 * The group  id is stored in $_gid session variable.
 *
 *
 *                    VARIABLES AFFECTING THE SCRIPT BEHAVIOR
 *
 * string  $login
 * string  $password
 * boolean $logout
 *
 * string  $cidReq   : course id requested
 * boolean $cidReset : ask for a course Reset, if no $cidReq is provided in the
 *                     same time, all course informations is removed from the
 *                     current session
 *
 * int     $gidReq   : group Id requested
 * boolean $gidReset : ask for a group Reset, if no $gidReq is provided in the
 *                     same time, all group informations is removed from the
 *                     current session
 *
 *
 *                   VARIABLES SET AND RETURNED BY THE SCRIPT
 *
 * All the variables below are set and returned by this script.
 *
 * USER VARIABLES
 *
 * string    $_user ['firstName'   ]
 * string    $_user ['lastName'    ]
 * string    $_user ['mail'        ]
 * string    $_user ['lastLogin'   ]
 * string    $_user ['official_code']
 * string    $_user ['picture_uri'  ]
 * string    $_user['user_id']
 *
 * boolean $is_platformAdmin
 * boolean $is_allowedCreateCourse
 *
 * COURSE VARIABLES
 * see the function get_course_info_with_category
* boolean $is_courseMember
* boolean $is_courseTutor
* boolean $is_courseAdmin
*
*
* GROUP VARIABLES
*
* int     $_gid (the group id)
*
*
*                       IMPORTANT ADVICE FOR DEVELOPERS
*
* We strongly encourage developers to use a connection layer at the top of
* their scripts rather than use these variables, as they are, inside the core
* of their scripts. It will make code maintenance much easier.
*
*    Many if the functions you need you can already find in the
*    main_api.lib.php
*
* We encourage you to use functions to access these global "kernel" variables.
* You can add them to e.g. the main API library.
*
*
*                               SCRIPT STRUCTURE
*
* 1. The script determines if there is an authentication attempt. This part
* only chek if the login name and password are valid. Afterwards, it set the
* $_user['user_id'] (user id) and the $uidReset flag. Other user informations are retrieved
* later. It's also in this section that optional external authentication
* devices step in.
*
* 2. The script determines what other session informations have to be set or
* reset, setting correctly $cidReset (for course) and $gidReset (for group).
*
* 3. If needed, the script retrieves the other user informations (first name,
		* last name, ...) and stores them in session.
*
* 4. If needed, the script retrieves the course information and stores them
* in session
*
* 5. The script initializes the user permission status and permission for the
* course level
*
* 6. If needed, the script retrieves group informations an store them in
* session.
*
* 7. The script initializes the user status and permission for the group level.
*
*    @package chamilo.include
*/

/*
	 INIT SECTION
	 variables should be initialised here
 */

//require_once api_get_path(LIBRARY_PATH).'conditionallogin.lib.php'; moved to autologin
// verified if exists the username and password in session current

use \ChamiloSession as Session;

//Conditional login
if (isset($_SESSION['conditional_login']['uid']) && $_SESSION['conditional_login']['can_login']=== true){
	$uData = UserManager::get_user_info_by_id($_SESSION['conditional_login']['uid']);
	ConditionalLogin::check_conditions($uData);

	$_user['user_id'] = $_SESSION['conditional_login']['uid'];
	$_user['status']  = $uData['status'];
	Session::write('_user',$_user);
	Session::erase('conditional_login');
	$uidReset=true;
	event_login();
}

// parameters passed via GET
$logout = isset($_GET["logout"]) ? $_GET["logout"] : '';
$gidReq = isset($_GET["gidReq"]) ? Database::escape_string($_GET["gidReq"]) : '';

//this fixes some problems with generic functionalities like
//My Agenda & What's New icons linking to courses
// $cidReq can be set in the index.php file of a course-area
$cidReq = isset($cidReq) ? Database::escape_string($cidReq) : '';
// $cidReq can be set in URL-parameter
$cidReq = isset($_GET["cidReq"]) ? Database::escape_string($_GET["cidReq"]) : $cidReq;
$cidReset = isset($cidReset) ? Database::escape_string($cidReset) : '';

// $cidReset can be set in URL-parameter
$cidReset = (isset($_GET['cidReq']) && ((isset($_SESSION['_cid']) && $_GET['cidReq']!=$_SESSION['_cid']) || (!isset($_SESSION['_cid'])))) ? Database::escape_string($_GET["cidReq"]) : $cidReset;

// $cDir is a special url param sent by courses/.htaccess
$cDir = (!empty($_GET['cDir']) ? $_GET['cDir'] : null);

$gidReset = isset($gidReset) ? $gidReset : '';
// $gidReset can be set in URL-parameter

// parameters passed via POST
$login = isset($_POST["login"]) ? $_POST["login"] : '';

/* 	 MAIN CODE  */

if (!empty($_SESSION['_user']['user_id']) && ! ($login || $logout)) {
	// uid is in session => login already done, continue with this value
	$_user['user_id'] = $_SESSION['_user']['user_id'];
    //Check if we have to reset user data
    //This param can be used to reload user data if user has been logged by external script
    if (isset($_SESSION['_user']['uidReset']) && $_SESSION['_user']['uidReset']){
        $uidReset=true;
    }
} else {
	if (isset($_user['user_id'])) {
		unset($_user['user_id']);
	}
    
    //Platform legal terms and conditions
	if (api_get_setting('allow_terms_conditions') == 'true') {
		if (isset($_POST['login']) && isset($_POST['password']) && isset($_SESSION['term_and_condition']['user_id'])) {
			$user_id = $_SESSION['term_and_condition']['user_id'];    // user id
			// Update the terms & conditions
            $legal_type = null;
			//verify type of terms and conditions
            if (isset($_POST['legal_info'])) {
                $info_legal = explode(':', $_POST['legal_info']);
                $legal_type = LegalManager::get_type_of_terms_and_conditions($info_legal[0], $info_legal[1]);
            }

			//is necessary verify check
			if ($legal_type == 1) {
				if ((isset($_POST['legal_accept']) && $_POST['legal_accept']=='1')) {
					$legal_option = true;
				} else {
					$legal_option = false;
				}
			}

			//no is check option
			if ($legal_type == 0) {
				$legal_option=true;
			}

			if (isset($_POST['legal_accept_type']) && $legal_option===true) {
				$cond_array = explode(':',$_POST['legal_accept_type']);
				if (!empty($cond_array[0]) && !empty($cond_array[1])){
					$time = time();
					$condition_to_save = intval($cond_array[0]).':'.intval($cond_array[1]).':'.$time;
					UserManager::update_extra_field_value($user_id,'legal_accept',$condition_to_save);
				}
			}
		}
	}

	//IF cas is activated and user isn't logged in
	if (api_get_setting('cas_activate') == 'true') {
		$cas_activated = true;
	} else {
		$cas_activated = false;
	}

	$cas_login=false;
	if ($cas_activated  AND !isset($_user['user_id']) and !isset($_POST['login'])  && !$logout) {
		require_once(api_get_path(SYS_PATH).'main/auth/cas/authcas.php');
		$cas_login = cas_is_authenticated();
	}
	if ( ( isset($_POST['login']) AND  isset($_POST['password']) ) OR ($cas_login) )  {

		// $login && $password are given to log in
		if ( $cas_login  && empty($_POST['login']) ) {
			$login = $cas_login;
		} else {
			$login      = $_POST['login'];
			$password   = $_POST['password'];
		}
        
		//Lookup the user in the main database
		$user_table = Database::get_main_table(TABLE_MAIN_USER);
		$sql = "SELECT user_id, username, password, auth_source, active, expiration_date, status FROM $user_table
			    WHERE username = '".Database::escape_string($login)."'";
		$result = Database::query($sql);

		if (Database::num_rows($result) > 0) {
			$uData = Database::fetch_array($result);

			if ($uData['auth_source'] == PLATFORM_AUTH_SOURCE || $uData['auth_source'] == CAS_AUTH_SOURCE) {
				//The authentification of this user is managed by Chamilo itself
                $password = api_get_encrypted_password(trim(stripslashes($password)));
       			
				// Check the user's password
				if ( ($password == $uData['password']  OR $cas_login) AND (trim($login) == $uData['username'])) {    
                    $update_type = UserManager::get_extra_user_data_by_field($uData['user_id'], 'update_type');
                    $update_type= $update_type['update_type'];
                    if (!empty($extAuthSource[$update_type]['updateUser']) && file_exists($extAuthSource[$update_type]['updateUser'])) {
                        include_once $extAuthSource[$update_type]['updateUser'];
                    }
                                        
					// Check if the account is active (not locked)
					if ($uData['active'] == '1') {

						// Check if the expiration date has not been reached
                        if ($uData['expiration_date'] > date('Y-m-d H:i:s') OR $uData['expiration_date'] == '0000-00-00 00:00:00') {
							global $_configuration;

                            if (isset($_configuration['multiple_access_urls']) && $_configuration['multiple_access_urls']) {
								//Check if user is an admin
                                $my_user_is_admin = UserManager::is_admin($uData['user_id']);

								// This user is subscribed in these sites => $my_url_list
								$my_url_list = api_get_access_url_from_user($uData['user_id']);

								//Check the access_url configuration setting if the user is registered in the access_url_rel_user table
								//Getting the current access_url_id of the platform
								$current_access_url_id = api_get_current_access_url_id();

								if ($my_user_is_admin === false) {

									if (is_array($my_url_list) && count($my_url_list)>0 ) {
										// the user have the permissions to enter at this site
										if (in_array($current_access_url_id, $my_url_list)) {
											ConditionalLogin::check_conditions($uData);

											$_user['user_id'] = $uData['user_id'];
											$_user['status']  = $uData['status'];
											Session::write('_user',$_user);
											event_login();
										} else {
											$loginFailed = true;
											Session::erase('_uid');
											header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=access_url_inactive');
											exit;
										}
									} else {
										$loginFailed = true;
										Session::erase('_uid');
										header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=access_url_inactive');
										exit;
									}
								} else { //Only admins of the "main" (first) Chamilo portal can login wherever they want
									//var_dump($current_access_url_id, $my_url_list); exit;
									if (in_array(1, $my_url_list)) { //Check if this admin have the access_url_id = 1 which means the principal
										ConditionalLogin::check_conditions($uData);
										$_user['user_id'] = $uData['user_id'];
										$_user['status']  = $uData['status'];
										Session::write('_user',$_user);
										event_login();
									} else {
										//This means a secondary admin wants to login so we check as he's a normal user
										if (in_array($current_access_url_id, $my_url_list)) {
											$_user['user_id'] = $uData['user_id'];
											$_user['status']  = $uData['status'];
											Session::write('_user',$_user);
											event_login();
										} else {
											$loginFailed = true;
											Session::erase('_uid');
											header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=access_url_inactive');
											exit;
										}
									}
								}
                            } else {
                                //error_log('Loggedin');
								ConditionalLogin::check_conditions($uData);
                                $_user['user_id'] = $uData['user_id'];
                                $_user['status']  = $uData['status'];

                                Session::write('_user',$_user);
                                event_login();
							}
						} else {
							$loginFailed = true;
							Session::erase('_uid');
							header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=account_expired');
							exit;
						}
					} else {
						$loginFailed = true;
						Session::erase('_uid');
						header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=account_inactive');
						exit;
					}
				} else {
					// login failed: username or password incorrect
					$loginFailed = true;
					Session::erase('_uid');
					header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=user_password_incorrect');
					exit;
				}

				if (isset($uData['creator_id']) && $_user['user_id'] != $uData['creator_id']) {
					//first login for a not self registred
					//e.g. registered by a teacher
					//do nothing (code may be added later)
				}
			} elseif (!empty($extAuthSource[$uData['auth_source']]['login']) && file_exists($extAuthSource[$uData['auth_source']]['login'])) {
				/*
				 * Process external authentication
				 * on the basis of the given login name
				 */
				$loginFailed = true;  // Default initialisation. It could
				// change after the external authentication
				$key = $uData['auth_source']; //'ldap','shibboleth'...
				/* >>>>>>>> External authentication modules <<<<<<<<< */
				// see configuration.php to define these
				include_once($extAuthSource[$key]['login']);
				/* >>>>>>>> External authentication modules <<<<<<<<< */
			} else { // no standard Chamilo login - try external authentification
				//huh... nothing to do... we shouldn't get here
				error_log('Chamilo Authentication file '. $extAuthSource[$uData['auth_source']]['login']. ' could not be found - this might prevent your system from doing the corresponding authentication process',0);
			}
		} else {
			// login failed, Database::num_rows($result) <= 0
			$loginFailed = true;  // Default initialisation. It could
			// change after the external authentication

			/*
			 * In this section:
			 * there is no entry for the $login user in the Chamilo
			 * database. This also means there is no auth_source for the user.
			 * We let all external procedures attempt to add him/her
			 * to the system.
			 *
			 * Process external login on the basis
			 * of the authentication source list
			 * provided by the configuration settings.
			 * If the login succeeds, for going further,
			 * Chamilo needs the $_user['user_id'] variable to be
			 * set and registered in the session. It's the
			 * responsability of the external login script
			 * to provide this $_user['user_id'].
			 */

			if (isset($extAuthSource) && is_array($extAuthSource)) {
				foreach($extAuthSource as $thisAuthSource) {
					if (!empty($thisAuthSource['newUser']) && file_exists($thisAuthSource['newUser'])) {
						include_once($thisAuthSource['newUser']);
					} else {
						error_log('Chamilo Authentication file '. $thisAuthSource['newUser']. ' could not be found - this might prevent your system from using the authentication process in the user creation process',0);
					}
				}
			} //end if is_array($extAuthSource)
			if ($loginFailed) { //If we are here username given is wrong
				header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=user_password_incorrect');
			}
		} //end else login failed
	} elseif (api_get_setting('sso_authentication')==='true' &&  !in_array('webservices', explode('/', $_SERVER['REQUEST_URI']))) {
		/**
		 * TODO:
		 * - Work on a better validation for webservices paths. Current is very poor and exit
		 */
		$subsso = api_get_setting('sso_authentication_subclass');
		//require_once(api_get_path(SYS_CODE_PATH).'auth/sso/sso.class.php'); moved to autologin
		if (!empty($subsso)) {
			require_once(api_get_path(SYS_CODE_PATH).'auth/sso/sso.'.$subsso.'.class.php');
			$subsso = 'sso'.$subsso;
			$osso = new $subsso(); //load the subclass
		} else {
			$osso = new sso();
		}
		if (isset($_SESSION['_user']['user_id'])) {
			if ($logout) {
				// Make custom redirect after logout
				online_logout($_SESSION['_user']['user_id'], false);
				$osso->logout(); //redirects and exits
			}
		} elseif(!$logout) {
			// Handle cookie comming from Master Server
			if (!isset($_GET['sso_referer']) && !isset($_GET['loginFailed'])) {
				// Redirect to master server
				$osso->ask_master();
			} elseif (isset($_GET['sso_cookie'])) {
				// Here we are going to check the origin of
				// what the call says should be used for
				// authentication, and ensure  we know it
				$matches_domain = false;
				if (isset($_GET['sso_referer'])) {
					$protocol = api_get_setting('sso_authentication_protocol');
					// sso_authentication_domain can list
					// several, comma-separated, domains
					$master_urls = split(',',api_get_setting('sso_authentication_domain'));
					if (!empty($master_urls)) {
					    $master_auth_uri = api_get_setting('sso_authentication_auth_uri');
                        foreach ($master_urls as $mu) {
                            if (empty($mu)) { continue; }
                            // for each URL, check until we find *one* that matches the $_GET['sso_referer'], then skip the rest
                            if ($protocol.trim($mu).$master_auth_uri === $_GET['sso_referer']) {
                                $matches_domain = true;
                                break;
                            }
                        }
                    } else {
                        error_log('Your sso_authentication_master param is empty. Check the platform configuration, security section. It can be a list of comma-separated domains');
                    }
                }
				if ($matches_domain) { 
                                        //make all the process of checking
                                        //if the user exists (delegated to the sso class)
                                        $osso->check_user();

				} else {
					error_log('Check the sso_referer URL in your script, it doesn\'t match any of the possibilities');
					//Request comes from unknown source
					$loginFailed = true;
					Session::erase('_uid');
					header('Location: '.api_get_path(WEB_PATH).'index.php?loginFailed=1&error=unrecognize_sso_origin');
					exit;
				}
			}
		}//end logout ... else ... login
	} elseif (api_get_setting('openid_authentication')=='true') {
		if (!empty($_POST['openid_url'])) {
			include 'main/auth/openid/login.php';
			openid_begin(trim($_POST['openid_url']),api_get_path(WEB_PATH).'index.php');
			//this last function should trigger a redirect, so we can die here safely
			die('Openid login redirection should be in progress');
		} elseif (!empty($_GET['openid_identity'])) {
			//it's usual for PHP to replace '.' (dot) by '_' (underscore) in URL parameters
			include('main/auth/openid/login.php');
			$res = openid_complete($_GET);
			if ($res['status'] == 'success') {
				$id1 = Database::escape_string($res['openid.identity']);
				//have another id with or without the final '/'
				$id2 = (substr($id1,-1,1)=='/'?substr($id1,0,-1):$id1.'/');
				//lookup the user in the main database
				$user_table = Database::get_main_table(TABLE_MAIN_USER);
				$sql = "SELECT user_id, username, password, auth_source, active, expiration_date
					FROM $user_table
					WHERE openid = '$id1'
					OR openid = '$id2' ";
				$result = Database::query($sql);
				if ($result !== false) {
					if (Database::num_rows($result)>0) {
						//$row = Database::fetch_array($res);
						$uData = Database::fetch_array($result);

						if ($uData['auth_source'] == PLATFORM_AUTH_SOURCE) {
							//the authentification of this user is managed by Chamilo itself

							// check if the account is active (not locked)
							if ($uData['active']=='1') {
								// check if the expiration date has not been reached
								if ($uData['expiration_date']>date('Y-m-d H:i:s') OR $uData['expiration_date']=='0000-00-00 00:00:00') {
									$_user['user_id'] = $uData['user_id'];
									$_user['status']  = $uData['status'];

									Session::write('_user',$_user);
									event_login();
								} else {
									$loginFailed = true;
									Session::erase('_uid');
									header('Location: index.php?loginFailed=1&error=account_expired');
									exit;
								}
							} else {
								$loginFailed = true;
								Session::erase('_uid');
								header('Location: index.php?loginFailed=1&error=account_inactive');
								exit;
							}
							if (isset($uData['creator_id']) && $_user['user_id'] != $uData['creator_id']) {
								//first login for a not self registred
								//e.g. registered by a teacher
								//do nothing (code may be added later)
							}
						}
					} else {
						//Redirect to the subscription form
						header('Location: '.api_get_path(WEB_CODE_PATH).'auth/inscription.php?username='.$res['openid.sreg.nickname'].'&email='.$res['openid.sreg.email'].'&openid='.$res['openid.identity'].'&openid_msg=idnotfound');
						//$loginFailed = true;
					}
				} else {
					$loginFailed = true;
				}
			} else {
				$loginFailed = true;
			}
		}
	} elseif (KeyAuth::is_enabled()) {
        $success = KeyAuth::instance()->login();
        if($success)
        {
            $use_anonymous = false;
        }
    }

	//    else {} => continue as anonymous user
	$uidReset = true;

	//    $cidReset = true;
	//    $gidReset = true;
} // end else

//Now check for anonymous user mode
if (isset($use_anonymous) && $use_anonymous) {
	//if anonymous mode is set, then try to set the current user as anonymous
	//if he doesn't have a login yet
	api_set_anonymous();
} else {
	//if anonymous mode is not set, then check if this user is anonymous. If it
	//is, clean it from being anonymous (make him a nobody :-))
	api_clear_anonymous();
}

// if there is a cDir parameter in the URL (coming from courses/.htaccess redirection)
if (!empty($cDir)) {
	$c = CourseManager::get_course_id_from_path($cDir);
	if ($c) { $cidReq = $c; }
}

// if the requested course is different from the course in session

if (!empty($cidReq) && (!isset($_SESSION['_cid']) or (isset($_SESSION['_cid']) && $cidReq != $_SESSION['_cid']))) {    
	$cidReset = true;
	$gidReset = true;    // As groups depend from courses, group id is reset
}

// if the requested group is different from the group in session
$gid = isset($_SESSION['_gid']) ? $_SESSION['_gid'] : '';
if ($gidReq && $gidReq != $gid) {
	$gidReset = true;
}


/* USER INIT */

if (isset($uidReset) && $uidReset) {    // session data refresh requested
    unset($_SESSION['_user']['uidReset']);
    $is_platformAdmin = false;
    $is_allowedCreateCourse = false;

	if (isset($_user['user_id']) && $_user['user_id'] && ! api_is_anonymous()) {
        // a uid is given (log in succeeded)
		$user_table     = Database::get_main_table(TABLE_MAIN_USER);
		$admin_table    = Database::get_main_table(TABLE_MAIN_ADMIN);
		$track_e_login  = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_LOGIN);

		$sql = "SELECT user.*, a.user_id is_admin, UNIX_TIMESTAMP(login.login_date) login_date
			FROM $user_table
			LEFT JOIN $admin_table a
			ON user.user_id = a.user_id
			LEFT JOIN $track_e_login login
			ON user.user_id  = login.login_user_id
			WHERE user.user_id = '".$_user['user_id']."'
			ORDER BY login.login_date DESC LIMIT 1";

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

		if (Database::num_rows($result) > 0) {
			// Extracting the user data

			$uData = Database::fetch_array($result);

			$_user ['firstName']        = $uData ['firstname' ];
			$_user ['lastName' ]        = $uData ['lastname'  ];
			$_user ['mail'     ]        = $uData ['email'     ];
			$_user ['lastLogin']        = $uData ['login_date'];
			$_user ['official_code']    = $uData ['official_code'];
			$_user ['picture_uri']      = $uData ['picture_uri'];
			$_user ['user_id']          = $uData ['user_id'];
			$_user ['language']         = $uData ['language'];
			$_user ['auth_source']      = $uData ['auth_source'];
			$_user ['theme']            = $uData ['theme'];
			$_user ['status']           = $uData ['status'];

			$is_platformAdmin           = (bool) (! is_null( $uData['is_admin']));
			$is_allowedCreateCourse     = (bool) (($uData ['status'] == COURSEMANAGER) or (api_get_setting('drhCourseManagerRights') and $uData['status'] == DRH));
			ConditionalLogin::check_conditions($uData);

			Session::write('_user',$_user);
			UserManager::update_extra_field_value($_user['user_id'], 'already_logged_in', 'true');
			Session::write('is_platformAdmin',$is_platformAdmin);
			Session::write('is_allowedCreateCourse',$is_allowedCreateCourse);

            // If request_uri is setted we have to go further to have course permissions
            /*if (empty($_SESSION['request_uri']) || !isset($_SESSION['request_uri'])) {
                if (isset($_SESSION['noredirection'])) {
                    //If we just want to reset info without redirecting user
                    unset($_SESSION['noredirection']);
                } else {
                    LoginRedirection::redirect();
                }
            }*/
		} else {
			header('location:'.api_get_path(WEB_PATH));
			//exit("WARNING UNDEFINED UID !! ");
		}
	} else { // no uid => logout or Anonymous
		Session::erase('_user');
		Session::erase('_uid');
	}

	Session::write('is_platformAdmin',$is_platformAdmin);
	Session::write('is_allowedCreateCourse',$is_allowedCreateCourse);
} else { // continue with the previous values
    $_user                    = $_SESSION['_user'];
    $is_platformAdmin         = isset($_SESSION['is_platformAdmin']) ? $_SESSION['is_platformAdmin'] : false;
    $is_allowedCreateCourse   = isset($_SESSION['is_allowedCreateCourse']) ? $_SESSION['is_allowedCreateCourse'] : false;
}

/*  COURSE INIT */

if (isset($cidReset) && $cidReset) {
    // Course session data refresh requested or empty data
	if ($cidReq) {    
        $_course = CourseManager::get_course_info_with_category($cidReq);
        
		if (!empty($_course)) {		         			
            
            //@TODO real_cid should be cid, for working with numeric course id
            $_real_cid                      = $_course['real_id'];
			$_cid                           = $_course['code'];
            
            Session::write('_real_cid', $_real_cid);
			Session::write('_cid',      $_cid);
			Session::write('_course',   $_course);

			// if a session id has been given in url, we store the session
			
            // Database Table Definitions
            $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);

            if (!empty($_GET['id_session'])) {
                $_SESSION['id_session'] = intval($_GET['id_session']);
                $sql = 'SELECT name FROM '.$tbl_session . ' WHERE id="'.intval($_SESSION['id_session']) . '"';
                $rs = Database::query($sql);
                list($_SESSION['session_name']) = Database::fetch_array($rs);
            } else {
                Session::erase('session_name');
                Session::erase('id_session');
            }
			

            if (!isset($_SESSION['login_as'])) {
				//Course login
                if (isset($_user['user_id'])) {
                    event_course_login($_course['code'], $_user['user_id'], api_get_session_id());
                }
            }
        } else {
            //exit("WARNING UNDEFINED CID !! ");
            header('location:'.api_get_path(WEB_PATH));
        }
    } else {
        Session::erase('_cid');
        Session::erase('_real_cid');
        Session::erase('_course');

        if (!empty($_SESSION)) {
                foreach($_SESSION as $key => $session_item) {
                if (strpos($key,'lp_autolunch_') === false) {
                    continue;
                } else {
                    if (isset($_SESSION[$key])) {
                        Session::erase($key);
                    }
                }
            }
        }
        //Deleting session info
        if (api_get_session_id()) {
            Session::erase('id_session');
            Session::erase('session_name');
        }
    }
} else {
    
    // Continue with the previous values
    
    if (empty($_SESSION['_course']) && !empty($_SESSION['_cid'])) {
        //Just in case $_course is empty we try to load if the c_id still exists
        $_course = CourseManager::get_course_info_with_category($_SESSION['_cid']);
        if (!empty($_course)) {
            $_real_cid                      = $_course['real_id'];
            $_cid                           = $_course['code'];

            Session::write('_real_cid', $_real_cid);
            Session::write('_cid',      $_cid);
            Session::write('_course',   $_course);
        }
    }
    
    if (empty($_SESSION['_course']) OR empty($_SESSION['_cid'])) { //no previous values...
        $_cid         = -1;        //set default values that will be caracteristic of being unset
        $_course      = -1;
    } else {
        $_cid      = $_SESSION['_cid'   ];
        $_course   = $_SESSION['_course'];

           // these lines are usefull for tracking. Indeed we can have lost the id_session and not the cid.
           // Moreover, if we want to track a course with another session it can be usefull
        if (!empty($_GET['id_session'])) {
            $tbl_session                 = Database::get_main_table(TABLE_MAIN_SESSION);
            $sql = 'SELECT name FROM '.$tbl_session . ' WHERE id="'.intval($_SESSION['id_session']). '"';
            $rs = Database::query($sql);
            list($_SESSION['session_name']) = Database::fetch_array($rs);
            $_SESSION['id_session']         = intval($_GET['id_session']);
        }

        if (!isset($_SESSION['login_as'])) {
            $save_course_access = true;

            //The value  $_dont_save_user_course_access should be added before the call of global.inc.php see the main/inc/chat.ajax.php file
            //Disables the updates in the TRACK_E_COURSE_ACCESS table
            if (isset($_dont_save_user_course_access) && $_dont_save_user_course_access == true) {
                $save_course_access = false;
            }

            if ($save_course_access) {
                $course_tracking_table = Database :: get_statistic_table(TABLE_STATISTIC_TRACK_E_COURSE_ACCESS);

                /*
                * When $_configuration['session_lifetime'] is too big 100 hours (in order to let users take exercises with no problems)
                * the function Tracking::get_time_spent_on_the_course() returns big values (200h) due the condition:
                * login_course_date > now() - INTERVAL $session_lifetime SECOND
                *
                */
                /*
                if (isset($_configuration['session_lifetime'])) {
                    $session_lifetime    = $_configuration['session_lifetime'];
                } else {
                    $session_lifetime    = 3600; // 1 hour
                }*/

                $session_lifetime    = 3600; // 1 hour

                $course_code = $_course['sysCode'];
                $time = api_get_datetime();

                if (isset($_user['user_id']) && !empty($_user['user_id'])) {

                    //We select the last record for the current course in the course tracking table
                    //But only if the login date is < than now + max_life_time
                    $sql = "SELECT course_access_id FROM $course_tracking_table
                            WHERE   user_id     = ".intval($_user ['user_id'])." AND
                                    course_code = '$course_code' AND
                                    session_id  = ".api_get_session_id()." AND
                                    login_course_date > now() - INTERVAL $session_lifetime SECOND
                        ORDER BY login_course_date DESC LIMIT 0,1";
                    $result = Database::query($sql);

                    if (Database::num_rows($result) > 0) {
                        $i_course_access_id = Database::result($result,0,0);
                        //We update the course tracking table
                        $sql = "UPDATE $course_tracking_table  SET logout_course_date = '$time', counter = counter+1
                                WHERE course_access_id = ".intval($i_course_access_id)." AND session_id = ".api_get_session_id();
                        //error_log($sql);
                        Database::query($sql);
                    } else {
                        $sql="INSERT INTO $course_tracking_table (course_code, user_id, login_course_date, logout_course_date, counter, session_id)" .
                            "VALUES('".$course_code."', '".$_user['user_id']."', '$time', '$time', '1','".api_get_session_id()."')";
                        //error_log($sql);
                        Database::query($sql);
                    }
                }
            }
        }
    }
}

/*  COURSE / USER REL. INIT */

$session_id = api_get_session_id();
$user_id    = isset($_user['user_id']) ? $_user['user_id'] : null;

//Course permissions
$is_courseAdmin     = false; //course teacher
$is_courseTutor     = false; //course teacher - some rights
$is_courseMember    = false; //course student
$is_courseCoach     = false; //course coach

//Course - User permissions
$is_sessionAdmin    = false;

if ((isset($uidReset) && $uidReset) || (isset($cidReset) && $cidReset)) {
    
    if (isset($_cid) && $_cid) {
        $my_user_id = isset($user_id) ? intval($user_id) : 0;
        $variable = 'accept_legal_'.$my_user_id.'_'.$_course['real_id'].'_'.$session_id;
        
        $user_pass_open_course = false;
        if (api_check_user_access_to_legal($_course['visibility']) && Session::read($variable)) {
            $user_pass_open_course = true;
        } 

        //Checking if the user filled the course legal agreement
        if ($_course['activate_legal'] == 1 && !api_is_platform_admin()) {
            $user_is_subscribed = CourseManager::is_user_accepted_legal($user_id, $_course['id'], $session_id) || $user_pass_open_course;
            if (!$user_is_subscribed) {
                $url = api_get_path(WEB_CODE_PATH).'course_info/legal.php?course_code='.$_course['code'].'&session_id='.$session_id;                
                header('Location: '.$url);
                exit;
            }
        }
    }


    if (isset($user_id) && $user_id && isset($_cid) && $_cid) {
    
        //Check if user is subscribed in a course
        $course_user_table = Database::get_main_table(TABLE_MAIN_COURSE_USER);
        $sql = "SELECT * FROM $course_user_table
                   WHERE user_id  = '".$user_id."' AND relation_type <> ".COURSE_RELATION_TYPE_RRHH."
                   AND course_code = '$cidReq'";
        $result = Database::query($sql);

        $cuData = null;
        if (Database::num_rows($result) > 0) { // this  user have a recorded state for this course
            $cuData = Database::fetch_array($result, 'ASSOC');
            $is_courseAdmin      = (bool) ($cuData['status'] == 1 );
            $is_courseTutor      = (bool) ($cuData['tutor_id' ] == 1 );
            $is_courseMember     = true;

          
            $_courseUser['role'] = $cuData['role'];
            Session::write('_courseUser',$_courseUser);
        }

        //We are in a session course? Check session permissions
        if (!empty($session_id)) {
            //I'm not the teacher of the course
            if ($is_courseAdmin == false) {
                // this user has no status related to this course
                // The user is subscribed in a session? The user is a Session coach a Session admin ?

                $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);

				//Session coach, session admin, course coach admin
                $sql = "SELECT session.id_coach, session_admin_id, session_rcru.id_user
                		FROM $tbl_session session, $tbl_session_course_user session_rcru
					    WHERE  session_rcru.id_session  = session.id AND
					           session_rcru.course_code = '$_cid' AND
					           session_rcru.id_user     = '$user_id' AND
                               session_rcru.id_session  = $session_id AND
					           session_rcru.status      = 2";

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

                //I'm a session admin?
                if (isset($row) && isset($row[0]) && $row[0]['session_admin_id'] == $user_id) {
					$_courseUser['role'] = 'Professor';
	                $is_courseMember     = false;
	                $is_courseTutor      = false;
	                $is_courseAdmin      = false;
	                $is_courseCoach      = false;
	                $is_sessionAdmin     = true;
				} else {
                    //Im a coach or a student?
					$sql = "SELECT id_user, status FROM ".$tbl_session_course_user."
                            WHERE   course_code = '$_cid' AND
                                    id_user     = '".$user_id."' AND
                                    id_session  = '".$session_id."'
                            LIMIT 1";
					$result = Database::query($sql);

					if (Database::num_rows($result)) {
                        $row = Database::fetch_array($result, 'ASSOC');

                        $session_course_status = $row['status'];

                        switch ($session_course_status) {
                            case '2': // coach - teacher
                                $_courseUser['role'] = 'Professor';
                                $is_courseMember     = true;
                                $is_courseTutor      = true;
                                $is_courseCoach      = true;
                                $is_sessionAdmin     = false;

                                if (api_get_setting('extend_rights_for_coach') == 'true') {
                                    $is_courseAdmin = true;
                                } else {
                                    $is_courseAdmin = false;
                                }
                                Session::write('_courseUser', $_courseUser);
                                break;
                            case '0': //student
                                $_courseUser['role'] = '';
                                $is_courseMember     = true;
                                $is_courseTutor      = false;
                                $is_courseAdmin      = false;
                                $is_courseCoach      = false;
                                $is_sessionAdmin     = false;
                                Session::write('_courseUser', $_courseUser);
                                break;
                            default:
                                //unregister user
                                $_courseUser['role'] = '';                                
                                $is_courseMember     = false;
                                $is_courseTutor      = false;
                                $is_courseAdmin      = false;
                                $is_sessionAdmin     = false;
                                $is_courseCoach      = false;
                                Session::erase('_courseUser');
                                break;
                        }
					} else {
                        //unregister user
                        $is_courseMember     = false;
                        $is_courseTutor      = false;
                        $is_courseAdmin      = false;
                        $is_sessionAdmin     = false;
                        $is_courseCoach      = false;
                        Session::erase('_courseUser');
					}
				}
            }

            //If I'm the admin platform i'm a teacher of the course
            if ($is_platformAdmin) {
                $is_courseAdmin     = true;
            }
        }
    } else { // keys missing => not anymore in the course - user relation
        // course
        $is_courseMember    = false;
        $is_courseAdmin     = false;
        $is_courseTutor     = false;
        $is_courseCoach     = false;
        $is_sessionAdmin    = false;
        Session::erase('_courseUser');
    }

	//Checking the course access
    $is_allowed_in_course = false;
    
	if (isset($_course)) {
        switch ($_course['visibility']) {
            case COURSE_VISIBILITY_OPEN_WORLD: //3
                $is_allowed_in_course = true;
                break;
            case COURSE_VISIBILITY_OPEN_PLATFORM : //2
                if (isset($user_id) && !api_is_anonymous($user_id)) {
                    $is_allowed_in_course = true;
                }
                break;
            case COURSE_VISIBILITY_REGISTERED: //1
                if ($is_platformAdmin || $is_courseMember) {
                    $is_allowed_in_course = true;
                }
                break;
            case COURSE_VISIBILITY_CLOSED: //0
                if ($is_platformAdmin || $is_courseAdmin) {
                    $is_allowed_in_course = true;
                }
                break;
        }
	}
        
    // check the session visibility
	if ($is_allowed_in_course == true) {

		//if I'm in a session
		if ($session_id != 0) {
			if (!$is_platformAdmin) {
				// admin is not affected to the invisible session mode
				$session_visibility = api_get_session_visibility($session_id);

                switch ($session_visibility) {
                    case SESSION_INVISIBLE:
                        $is_allowed_in_course = false;
                        break;
                }
                //checking date
			}
        }
	}
    
	// save the states
    Session::write('is_courseAdmin', $is_courseAdmin);
	Session::write('is_courseMember', $is_courseMember);
	Session::write('is_courseTutor', $is_courseTutor);
    Session::write('is_courseCoach', $is_courseCoach);
	Session::write('is_allowed_in_course', $is_allowed_in_course);
	Session::write('is_sessionAdmin', $is_sessionAdmin);
} else { // continue with the previous values

	if (isset($_SESSION['_courseUser'])) {
		$_courseUser       = $_SESSION ['_courseUser'];
	}

    $is_courseAdmin       = isset($_SESSION ['is_courseAdmin']) ? $_SESSION ['is_courseAdmin'] : false;
    $is_courseTutor       = isset($_SESSION ['is_courseTutor']) ? $_SESSION ['is_courseTutor'] : false;
    $is_courseCoach       = isset($_SESSION ['is_courseCoach']) ? $_SESSION ['is_courseCoach'] : false;
	$is_courseMember      = isset($_SESSION ['is_courseMember']) ? $_SESSION ['is_courseMember'] : false;
	$is_allowed_in_course = isset($_SESSION ['is_allowed_in_course']) ? $_SESSION ['is_allowed_in_course'] : false;
}

/*  GROUP INIT */

if ((isset($gidReset) && $gidReset) || (isset($cidReset) && $cidReset)) { // session data refresh requested
	if ($gidReq && $_cid && !empty($_course['real_id'])) { // have keys to search data
		$group_table = Database::get_course_table(TABLE_GROUP);
		$sql = "SELECT * FROM $group_table WHERE c_id = ".$_course['real_id']." AND id = '$gidReq'";
		$result = Database::query($sql);
		if (Database::num_rows($result) > 0) { // This group has recorded status related to this course
			$gpData = Database::fetch_array($result);
			$_gid = $gpData ['id'];
			Session::write('_gid',$_gid);
		} else {
            Session::erase('_gid');
		}
	} elseif (isset($_SESSION['_gid']) or isset($_gid)) { // Keys missing => not anymore in the group - course relation
		Session::erase('_gid');
	}
} elseif (isset($_SESSION['_gid'])) { // continue with the previous values
	$_gid = $_SESSION ['_gid'];
} else { //if no previous value, assign caracteristic undefined value
	$_gid = -1;
}

//set variable according to student_view_enabled choices
if (api_get_setting('student_view_enabled') == "true") {
	if (isset($_GET['isStudentView'])) {
		if ($_GET['isStudentView'] == 'true') {
			if (isset($_SESSION['studentview'])) {
				if (!empty($_SESSION['studentview'])) {
					// switching to studentview
					$_SESSION['studentview'] = 'studentview';
				}
			}
		} elseif ($_GET['isStudentView'] == 'false') {
			if (isset($_SESSION['studentview'])) {
				if (!empty($_SESSION['studentview'])) {
					// switching to teacherview
					$_SESSION['studentview'] = 'teacherview';
				}
			}
		}
	} elseif (!empty($_SESSION['studentview'])) {
		//all is fine, no change to that, obviously
	} elseif (empty($_SESSION['studentview'])) {
		// We are in teacherview here
		$_SESSION['studentview'] = 'teacherview';
	}
}

if (isset($_cid)) {
	$tbl_course = Database::get_main_table(TABLE_MAIN_COURSE);
	$time = api_get_datetime();
	$sql="UPDATE $tbl_course SET last_visit= '$time' WHERE code='$_cid'";
	Database::query($sql);
}

Redirect::session_request_uri();

/*
$no_redirection = isset($no_redirection) ? $no_redirection : false;
if (!$no_redirection && (isset($_SESSION['request_uri']) && !empty($_SESSION['request_uri']))){
    $req= $_SESSION['request_uri'];
    unset($_SESSION['request_uri']);
    header('Location: '.$req);
    exit;
}
*/