<?php

function start_proxy_mode($id_user) {

	if(!permission_exists("activate_deactivate_proxy_mode", $id_user)) {
		$_SESSION['error_message']="Δεν έχετε τα απαραίτητα δικαιώματα να προβάλετε αυτή τη σελίδα.";
		default_page();
		return;
	}


	$user_data_i=mysql_fetch_array(query("SELECT * FROM __users WHERE id='".$id_user."'"));

	$_SESSION['user_proxy']=$_SESSION['user_logged'];

	$_SESSION['user_logged']=$id_user;
	$_SESSION['username']=$user_data_i['username'];
	$_SESSION['first_name']=$user_data_i['first_name'];
	$_SESSION['last_name']=$user_data_i['last_name'];
	
	initalize_roles();
	
	calculate_obligations();

	header("Location: ".CURRENT_SITE);
}


function end_proxy_mode() {

	if(!isset($_SESSION['user_proxy'])) {
		$_SESSION['error_message']="Δεν έχετε τα απαραίτητα δικαιώματα να προβάλετε αυτή τη σελίδα.";
		default_page();
		return;
	}

	$old_user=$_SESSION['user_logged'];

	$user_data_i=mysql_fetch_array(query("SELECT * FROM __users WHERE id='".$_SESSION['user_proxy']."'"));
	
	unset($_SESSION['user_proxy']);

	$_SESSION['user_logged']=$user_data_i['id'];
	$_SESSION['username']=$user_data_i['username'];
	$_SESSION['first_name']=$user_data_i['first_name'];
	$_SESSION['last_name']=$user_data_i['last_name'];
	$_SESSION['moderator']=array();
	/*+++*/
	$all_units_d=query("SELECT * FROM __units");
	while($all_units_i=mysql_fetch_array($all_units_d)) {
		if(moderator_role_exists($_SESSION['user_logged'], $all_units_i['id'])) {	
			$temparray=array('id' => $all_units_i['id'], 'name' => $all_units_i['name'], 'name_gen' => $all_units_i['name_gen']);
			array_push($_SESSION['moderator'] , $temparray);
		}
	}
	initalize_roles();
	calculate_obligations();

	header("Location: ?action=viewuser&userid=".$old_user);
}


function is_date($str) {

	$year=substr($str,0,4);
	$month=substr($str,5,2);
	$day=substr($str,8,2);
	
	if(checkdate($month,$day,$year)) return TRUE; 

	return FALSE;
}


function check_email($email) {

	return eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$", $email);
}


# Έλεγχος στο μέλλον αν είναι σωστή
function check_afm($afm) {

	if(!preg_match('/^(EL){0,1}[0-9]{9}$/i',$afm)) return false;
	if(strlen($afm)>9) $afm=substr($afm,2);

	$remainder=0;
	$sum=0;

	for($nn=2,$k=7,$sum=0;$k>=0;$k--,$nn+=$nn) $sum+=$nn*($afm[$k]);
	$remainder=$sum%11;

	return ($remainder==10)?$afm[8]=='0':$afm[8]==$remainder;
}

?>