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<?php
    session_start();
	$_SESSION['loggedIn'] = true;
    function is_logged() {
        if (isset($_SESSION['username'])) return $_SESSION['username'];
        else return false;
    }

        if( !isset($_SESSION['loggedIn']) && ($_SESSION['loggedIn'] != true) )
{
    // redirect the user to login screen if the session variable is not set and its value is not true
    header('location: login.php');
}

?>


<html>
<head>
	<title>Login</title>
</head>
<body>
<?php
if (!isset($_POST['submit'])){
?>
<!-- The HTML login form -->
	<form action="<?=$_SERVER['PHP_SELF']?>" method="post">
		Username: <input type="text" name="username" /><br />
		Password: <input type="password" name="password" /><br />

		<input type="submit" name="submit" value="Login" />
	</form>
<?php
} else {
	require_once("db_const.php");
	$mysqli = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);
	# check connection
	if ($mysqli->connect_errno) {
		echo "<p>MySQL error no {$mysqli->connect_errno} : {$mysqli->connect_error}</p>";
		exit();
	}

	$username = $_POST['username'];
	$password = $_POST['password'];

	$sql = "SELECT * from GEBRUIKERS WHERE username LIKE '{$username}' AND password LIKE '{$password}' LIMIT 1";
	$result = $mysqli->query($sql);
	if (!$result->num_rows == 1) {
		echo "<p>Invalid username/password combination</p>";
	} else {
		echo "<p>Logged in successfully</p>";
		// do stuffs
	}


	if (mysqli_num_rows($result) > 0) {
    // Output data of each row
    while($row = mysqli_fetch_assoc($result)) {
		$_SESSION['+login_user']=$user; // Initializing Session
		header("location: welcome.php"); // Redirecting To Other Page
    }
}


else {
	$error = "Username or Password is invalid";
}

mysqli_close($conn); // Closing Connection

}
?>
</body>
</html>