index.php

<?php

$amount = $_GET['amount'];
$name = "NAME";
$desc = "DESCRIPTION";
require_once('variables.php');

$params = array(
    'order_id' => '101',
    'amount' => $amount,
    'phone' => '',
    'name' => $name,
    'desc' => $desc,
    'callback' => URL_CALLBACK,
);

idpay_payment_create($params);

function idpay_payment_create($params)
{
    $header = array(
        'Content-Type: application/json',
        'X-API-KEY:' . APIKEY,
        'X-SANDBOX:' . SANDBOX,
    );

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, URL_PAYMENT);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($params));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

    $result = curl_exec($ch);
    curl_close($ch);

    $result = json_decode($result);

    if (empty($result) || empty($result->link)) {
        print 'Exception message:';
        print '<pre>';
        print_r($result);
        print '</pre>';
        return FALSE;
    }
    
    header('Location:' . $result->link);
}