Untitled

<?php
?>
<!DOCTYPE html>
<html lang="sv">
<head>
    <meta charset="utf-8"/>
    <title></title>
    <link rel="stylesheet" href="">
</head>

<body>
      <?php
if(isset($_POST["user"]) && isset($_POST["pass"]) && !empty($_POST["user"]) && !empty($_POST["pass"])) {
        $user = $_POST["user"];
        $pass = $_POST["pass"];

        $user = trim($user);
        $pass = trim($pass);

        $user = strtolower($user);
        $pass = strtolower($pass);


        echo "<p>.$user.</p>";
        echo "<p>.$pass.</p>";


        $userRegistered = false;
        $fil = fopen("C:/xampp/htdocs/users.txt", "a+") or die("Kunde inte öppna fil");

        if ($fil) {
                while (($rad = fgets($fil, 4096)) !== false) {
                    $rad = trim($rad);
                    if($rad == "user=$user"){
                        echo "<p>Användarnamnet är upptaget vänligen försök igen</p>";
                        $userRegistered = true;
                        break;
                    }
                }
            fclose($fil);

        }

    if (!$userRegistered) {
        $fil = fopen("C:/xampp/htdocs/users.txt", "a+") or die("Kunde inte öppna fil");
        $hash = password_hash($pass, PASSWORD_DEFAULT)."\n";
        echo password_hash($pass, PASSWORD_DEFAULT)."\n";
        fwrite($fil, "user=$user\n");
        fwrite($fil, "password=$hash\n");
        fclose($fil);
        }

}
    ?>
    <form method="post">
        <h2>Registrera</h2>
       <label>Username: </label><input type="text" name="user"><br>
       <label>Password: </label> <input type="password" name="pass"><br>
        <input type="submit">
    </form>
</body>
</html>