<?php
$connect = mysqli_connect("localhost", "id3199319_kbcmaster", "xplayers2305", "id3199319_kbcregistration");

$name = $_POST["name"];
$time = $_POST["time"];
$id = $_POST["id"];

function registerUser() {
    global $connect, $name, $time, $id;
    $statement = mysqli_prepare($connect, "INSERT INTO registration (name, time, id) VALUES (?, ?, ?)");
    mysqli_stmt_bind_param($statement, "sss", $name, $time, $id);
    mysqli_stmt_execute($statement);
    mysqli_stmt_close($statement);
}
function nameAvailable() {
    global $connect, $id;
    $statement = mysqli_prepare($connect, "SELECT * FROM registration WHERE id = ?");
    mysqli_stmt_bind_param($statement, "s", $id);
    mysqli_stmt_execute($statement);
    mysqli_stmt_store_result($statement);
    $count = mysqli_stmt_num_rows($statement);
    mysqli_stmt_close($statement);
    if ($count < 1){
        return true;
    }else {

           // Logic needs to be here as per requirement maybe

    return false;
    }
}
$response = array();
$response["success"] = false;
if (nameAvailable()){
    registerUser();
    $response["success"] = true;
}

echo json_encode($response);
?>