<?php
session_start();
if (!isset($_SESSION['loggedin'])) {
    exit("unauthorized");
}

include "../database.php";
require_once "../plugins/sendgrid/config.php";
require "../plugins/sendgrid/sendgrid-php.php";

$user_id = $_POST["user_id"];

$sql        = "SELECT * FROM stamps WHERE user_id='" . $user_id . "'";
$result     = mysqli_query($con, $sql);
$stamps = mysqli_fetch_assoc($result);

$sql    = "SELECT * FROM stamps WHERE user_id='" . $user_id . "'";
$result = mysqli_query($con, $sql);
if($result->num_rows > 0) {
    echo "presence";
} else {
    $sql    = "SELECT * FROM permissions WHERE user_id='" . $user_id . "'";
    $result = mysqli_query($con, $sql);
    if($result->num_rows > 0) {
        echo "presence";
    } else {
        $sql    = "SELECT * FROM transfers WHERE user_id='" . $user_id . "'";
        $result = mysqli_query($con, $sql);
        if($result->num_rows > 0) {
            echo "presence";
        } else {
            $sql_delete = "DELETE FROM users WHERE id = " . $user_id . "";
            if ($con->query($sql_delete) === true) {
                echo "ok";
            } else {
                echo "error";
            }
        }
    }
}