<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Refresh" content="5;url=welcome.php" />
</head>
<body>

<?php
include 'header.php';
require('conf.php');
session_start();                                            //session start duh
/*already logged in the session?*/
if(isset($_SESSION['uid']))
{
    $uid = $_SESSION["uid"];
    $array = mysql_query("SELECT * FROM users WHERE id = '" . $uid . "'");
    $tmp = mysql_fetch_array($array);
    logged($tmp);
}
/*maybe we are comming from login.php*/
elseif(isset($_POST["user"]))
{
    $user = $_POST["user"];
    $pass = $_POST["pass"];
    $array = mysql_query("SELECT * FROM users WHERE user = '" . $user . "'");
    $tmp = mysql_fetch_array($array);
    /*no user that name ?*/
    if(!$tmp)
    {
        echo "wrong user<br />";
        not_logged();
    }
    /*have the user, is the password right*/
    elseif($pass == $tmp["password"])
    {
        $_SESSION["uid"] = $tmp["id"];
        logged($tmp);
    }
    /*no the password is wrong*/
    else
    {
        echo "wrong password<br />";
        not_logged();
    }
}
/*all above failed , this page is loaded vanilla*/
else
{
    echo "no user <br />";
    not_logged();
}

/*logged case*/
function logged($data)
{
    ?>
logged as <?php echo $data["user"] ?> <br />
<a href='welcome.php'>enter the ....</a><br />
    <?php
}

/*not logged case*/
function not_logged()
{
    ?>
login failed <br />
<a href='welcome.php'>return to welcome</a><br />
    <?php
}
mysql_close($sql);
?>
</body>
</html>
