<?php
require_once('Database.class.php');
require_once('Hasher.class.php');

class Login {
	/** Decalare an empty __construct() so that the login function doesn't
	    get mistaken for the costructor. */
	public function __construct() {}
	
	public static function login($username, $password) {
		$db = Database::getInstance();
		$hasher = Hasher::getInstance();
		
		$uid = $db->getUID($username);
		if ($uid!==false && $db->getStatus($uid)>=3)
			$uid=false;
		if ($uid===false) {
			// user does not exist
			return 2;
		}
		$hash = $db->getPasswordHash($uid);
		if ($hasher->check($password, $hash)) {
			// success
			$_SESSION['uid'] = $uid;
			return 0;
		} else {
			// wrong password
			return 1;
		}
	}
	public static function isLoggedIn() {
		if ( isset($_SESSION['uid']) && ($_SESSION['uid']!='') ) {
			return $_SESSION['uid'];
		} else {
			return false;
		}
	}
	public static function logout() {
		$_SESSION['uid'] = '';
	}
}