<?php
include("config.php");
session_start();

if($_SERVER["REQUEST_METHOD"] == "POST") {
    // username and password sent from form

    $myusername = mysqli_real_escape_string($db,$_POST['username']);
    $mypassword = mysqli_real_escape_string($db,$_POST['password']);

    $sql = "SELECT id FROM admin WHERE username = '$myusername' and passcode = '$mypassword'";
    $result = (mysqli_query($db,$sql)) (mysqli_error($db));
    $row = mysqli_fetch_array($result,MYSQLI_ASSOC);
    $active = $row['active'];

    $count = mysqli_num_rows($result);

    // If result matched $myusername and $mypassword, table row must be 1 row

    if($count == 1) {
        session_register("myusername");
        $_SESSION['login_user'] = $myusername;

        header("location: welcome.php");
    }else {
        $error = "Your Login Name or Password is invalid";
    }
}