<?php
session_start();
if(isset($_SESSION['id'])) {
    header('Location: members.php');
}
else {
    include("database.php");
    $database = new database;
    $username = $_POST['username'];
    $password = md5($_POST['password']);
    $database->connect();
    $result = $database->query("SELECT * FROM `user` WHERE `user_name`='{$username}' AND `user_password`='{$password}'");
    if (mysql_num_rows($result) > 0) {
        $row = mysql_fetch_object($result);
        $_SESSION['id'] = $row->user_id;
        $_SESSION['name'] = $row->user_name;
        header('Location: members.php');
    }
    else {
        header('Location: index.php?login=incorrect');
    }
}
?>