plimbli k_user

<?php include "config/koneksi.php";
if(isset($_GET['hapus'])){
    $hapus="delete from user where id='$_GET[id]'";
    $war=mysqli_query($con,$hapus);
    if($war){
        echo "<script>alert('Data Terhapus')</script>";
    }
}
if(isset($_POST['simpan'])){
    $sim="insert into user values (null,'$_POST[username]','$_POST[password]')";
    $pan=mysqli_query($con,$sim);
    if($pan){
        echo "<script>alert('Data Tersimpan')</script>";
        echo "<script>document.location.href='k_user.php';</script>";
}
}
if (isset($_GET['edit'])) {
        $et = "SELECT * FROM user WHERE id = '$_GET[id]'";
        $it = mysqli_query($con,$et);
        $edit = mysqli_fetch_array($it);
    }
if (isset($_POST['update'])) {
    $up = "update user set nama='$_POST[nama_user]',username='$_POST[username]',password='$_POST[password]' WHERE id = '$_POST[kode_user]'";
    $da = mysqli_query($con,$up);
    if($da){
        echo "<script>alert('Data Terupdate');document.location.href='k_user.php';</script>";
    }else{
        echo "<script>alert('Data Gagal Terupdate ');document.location.href='k_user.php';</script>";
    }
}
?>
<html>
<head><title>Form Kelola User</title></head>
<form method="post">
    <table border=1>
        <tr>
            <td>ID</td>
            <td>:</td>
            <td><input type="text" name="kode_user" disabled="true" value="<?php echo @$edit[0] ?>"></td>
        </tr>
        <tr>
                <tr>
            <td>Username</td>
            <td>:</td>
            <td><input type="text" name="username" value="<?php echo @$edit[1] ?>"></td>
        </tr>
                <tr>
            <td>Password</td>
            <td>:</td>
            <td><input type="text" name="password" value="<?php echo @$edit[2] ?>"></td>
        </tr>
        <tr>
            <td colspan="2"></td>
            <td>
            <?php if(isset($_GET['edit'])){ ?>
            <input type="submit" name="update" value="Update">
            <?php }else{ ?>
            <input type="submit" name="simpan" value="Simpan">
            <?php } ?>
            <input type="submit" name="kembali" value="Logout">
            </td>
        </tr>
    <table border=1>
        <tr>
<input type="text" name="tcari" value=<?php echo @$_POST['tcari'] ?>>
<input type="submit" name="cari" value="Cari">
<input type="submit" name="R" value="Reset">
            <td>No</td>
            <td>ID</td>
            <td>Username</td>
            <td>Password</td>
            <td>Aksi</td>
        </tr>
        <?php
        $sql="select * from user";
        if(isset($_POST['cari'])){
            $sql="select * from user where nama like'%$_POST[tcari]%'";
        }
        if(isset($_POST['R'])){
            $sql="select * from user";
            echo "<script>document.location.href='k_user.php';</script>";
        }
        $qry=mysqli_query($con,$sql);
        $no=0;
        while($data=mysqli_fetch_array($qry)){
            $no++;
        ?>
        <tr>
            <td><?php echo $no ?></td>
            <td><?php echo $data[0] ?></td>
            <td><?php echo $data[1] ?></td>
            <td><?php echo $data[2] ?></td>
            <td><a href="k_user.php?hapus&id=<?php echo $data[0] ?>">Hapus</a> || <a href="k_user.php?edit&id=<?php echo $data[0] ?>">Edit</a></td>
        </tr>
        <?php } ?>

</form>
</html>