enrol.html

<div class="mdl-align">
    <h3><?php echo $instancename; ?></h3>
    <p><?php echo $message; ?></p>
    <p><b><?php echo get_string("cost").": {$instance->currency} {$localisedcost}"; ?></b></p>
    <div>
        <?php
            $data = [
                "cmd" => "_xclick",
                "charset" => "utf-8",
                "item_name" => s($coursefullname),
                "item_name" => s($coursefullname),
                "item_number" => s($courseshortname),
                "quantity" => "1",
                "on0" => get_string("user"),
                "os0" => s($userfullname),
                "custom" => "{$USER->id}-{$course->id}-{$instance->id}",
                "currency_code" => $instance->currency,
                "amount" => $cost,
                "for_auction" => "false",
                "no_note" => "1",
                "no_shipping" => "1" ,
                "rm" => "2",
                "first_name" => s($userfirstname),
                "last_name" => s($userlastname),
                "email" => s($useremail),
                "reference" => $reference,
                "custom_fields" => $customfields
            ];
        ?>
        <form method="post" action="<?php echo "$CFG->wwwroot/enrol/paystack/verify.php"?>">
            <?php
                foreach ($data as $key => $value) {
                    echo '<input type="hidden" name="' . $key . '" value="' . $value . '" />';
                }
            ?>
            <input type="hidden" name="charset" value="utf-8" />
            <input type="hidden" name="custom" value="<?php echo "{$USER->id}-{$course->id}-{$instance->id}" ?>" />

            <script src="https://js.paystack.co/v1/inline.js" 
                data-key="<?php echo $publickey; ?>"
                data-ref="<?php echo $reference; ?>" 
                data-firstname="<?php echo s($userfirstname) ?>"
                data-lastname="<?php echo s($userlastname) ?>"
                data-email="<?php p($useremail) ?>"
                data-currency="<?php p($instance->currency) ?>" 
                data-amount="<?php p($cost * 100) ?>"
                data-metadata='<?php echo json_encode($data) ?>' 
                data-locale="<?php echo current_language(); ?>">
            </script>
        </form>

    </div>