Membuat Fuction Registration di PHP

Jadi validasi formnya gak kebaca dan data yg diinputkan gak ke-save di databasenya. Setiap kali tes validasi form, tiba - tiba formnya itu hilang semua alias halamannya kosong. Dan setiap kali me-inputkan data ke formnya itu hasil error di bagian file register.php. Seharusnya ada sebuah notifikasi dan form registernya...

controller/register.php

<?php
//error_reporting(0);
include_once "../lib/connected.php";
include_once "../controller/activityLog.php";
include_once "../lib/generate_randomStr.php";

session_start();

// koneksi ke database
$dbconn = connected();

// deklarasi variabel
$username = " ";
$name     = " ";
$email    = " ";
$address  = " ";
$token    = " ";
$errors   = array();

if (isset($_POST['register_btn']  && $_POST['token'] == $_SESSION['csrf_token'])) {
    $token = generate_randomStr(16);
    register();
    csrf_token();
    email_queue();
}

function register(){
    global $dbconn, $errors, $username, $name, $email, $address, $token;

    $username        = e($_POST['username']);
    $name            = e($_POST['name']);
    $email           = e($_POST['email']);
    $password        = e(sha1($_POST['password']));
    $repeat_password = e(sha1($_POST['repeat_password']));
    $address         = e($_POST['address']);
    $token           = e($_POST['token']);

    // validasi form
    $usernameValidation = "/^[a-zA-Z][a-zA-Z0-9_]*$/";

    if((strlen($username) > 64)){
        array_push($errors, "username has exceeded 64 characters");
        header("Location: ../register/index.php");
        activityLog($username, "Register", "Someone failed to register because the inputting username exceeds 64 characters long");
    }else if(preg_match($usernameValidation, $username)){
        array_push($errors, "Username cannot begin with a number!");
        header("Location: ../register/index.php");
        activityLog($username, "Register", "GET", "Someone failed to register because the username entered cannot be preceded by numbers");
    }else if(!filter_var($email, FILTER_VALIDATE_EMAIL)) {
        array_push($errors, "Invalid email format");
        header("Location: ../register/index.php");
        activityLog($username, "Register", "POST", "Someone failed to register because invalid email format");
    }else if{
        // now check if the mail is already registered
        $query = pg_query($dbconn, "SELECT email FROM basicapp.bas_user WHERE email = '$email'");
        if(pg_fetch_array($query)[0] == $email) {
            array_push($errors, "This email already exists.");
            header("Location: ../register/index.php");
            activityLog($username, "Register", "GET", "Someone failed to register because the email already exists");
        }
    }else if($password != $repeat_password){
        array_push($errors, "The two pindex.phpassword do not match!");
        header("Location: ../register/");
        activityLog($username, "Register", "GET", "Someone failed to register because the name field is empty");
    }else if(count($errors) == 0){
        //enkripsi password sebelum disimpan didalam database
        $password = sha1($password);

        if(isset($_POST['register_btn'])){
            $register_btn = e($_POST['register_btn']);
            $query = "INSERT INTO basicapp.bas_user (username, name, email, password, address, is_active, activation_code)
                      VALUES('$username', '$name', '$email', '$password', '$address', '0', '$token')";
            $save_query = pg_query($dbconn, $query);

            $result = pg_affected_rows($save_query);
            // get id
            $logged_in_user_id = pg_last_oid($dbconn);
            if($result){
                $_SESSION['user'] = getUserById($logged_in_user_id);
                $_SESSION['success']  = "You are now logged in!";
                header('Location: ../login/index.php');
                activityLog($username, "Register", "GET", "Someone successfully to register with data fullname = $name, username = $username, email = $email, address = $address");
            }
            else{
                header("Location: ../register/index.php");
            }

        }
    }

}
//register();
var_dump(register());
var_dump(pg_last_error(register));

function getUserById($id){
    global $dbconn;
    $query = "SELECT * FROM basicapp.bas_user WHERE id = $id";
    $result = pg_query($dbconn, $query);

    $user = pg_fetch_assoc($result);
    return $user;
}
// escape string
function e($val){
    global $dbconn;
    return pg_escape_string($dbconn, trim($val));
}

register/index.php

<?php
include_once "../template/header.php";
?>
<div class="container">
    <div class="row">
        <div class="col-md-8 offset-md-2">
            <div class="card shadow">
                <div class="card-header">
                    <h2>Register</h2>
                </div>
                <div class="card-body">
                    <form class="row g-3"  action="<?= include_once "../controller/register.php"; ?>" method="POST">
                        <?php if(count($errors) > 0){ ?>
                            <div class="alert alert-danger" role="alert">
                                <?php
                                    foreach($errors as $error){
                                        echo $error . "<br>";
                                    }
                                ?>

                            </div>
                        <?php } ?>

                        <div class="col-md-12">
                            <label for="name" class="form-label">Fullname<span style="color: red;">*</span></label>
                            <input type="text" name="name" class="form-control" value="<?php echo $name; ?>" for="name" placeholder="enter fullname" required />
                        </div>
                        <div class="col-md-6">
                            <label for="name" class="form-label">Username<span style="color: red;">*</span></label>
                            <input type="text" name="username" class="form-control" value="<?php echo $username; ?>" for="username" placeholder="enter username" required />
                        </div>
                        <div class="col-md-6">
                            <label for="email" class="form-label">Email<span style="color: red;">*</span></label>
                            <input type="email" name="email" class="form-control" value="<?php echo $email; ?>" for="email" placeholder="enter email" required />
                            <input type="hidden" class="form-control" name="token" id="token" value="<?php echo $token; ?>">
                        </div>
                        <div class="col-md-6">
                            <label for="password" class="form-label">Password<span style="color: red;">*</span></label>
                            <input type="password" name="password" class="form-control" for="password" placeholder="enter new password" required />
                        </div>
                        <div class="col-md-6">
                            <label for="repeat_password" class="form-label">Repeat password<span style="color: red;">*</span></label>
                            <input type="password" name="repeat_password" class="form-control" placeholder="repeat new password" required />
                        </div>
                        <div class="col-md-12">
                            <label for="address" class="form-label">Address<span style="color: red;">*</span></label>
                            <input type="address" name="address" class="form-control" value="<?php echo $address; ?>" for="address" placeholder="enter address" required />
                        </div>
                        <div class="col-md-12 d-grid gap-2 mx-auto">
                            <input type="submit" class="btn text-white" name="register_btn" value="Register" />
                        </div>

                        <p class="text-muted">
                            Already have an account? <a href="../login/">Login</a>
                        </p>
                    </form>
                </div>
            </div>

        </div>
    </div>
</div>

<?php
include_once "../template/footer.php";
?>

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