Issue #112 Additional docs on how Sage Pay Form works.

Author: judgej

README.md

@@ -594,6 +594,12 @@ since the result will be safely saved in the database.
 
 Sage Pay Form requires neither a server-to-server back-channel nor
 IP-based security.
+It does not require pre-registration of a transaction, so is ideal for
+a speculative "pay now" button on a page for instant purchases of a
+product or service.
+Unlike `Direct` and `Server`, it does not support saved card references
+or tokens.
+
 The payment details are encrypted on the server before being sent to
 the gateway from the user's browser.
 The result is returned to the merchant site also through a client-side
@@ -622,7 +628,7 @@ $gateway = OmniPay::create('SagePay\Form')->initialize([
 
 The `encryptionKey` is generated in "My Sage Pay" when logged in as the administrator.
 
-Note that this gateway will assume all inout data (names, addresses etc.)
+Note that this gateway will assume all input data (names, addresses etc.)
 are UTF-8 encoded.
 It will then recode the data to ISO8859-1 before encrypting it for the gateway,
 as the gateway strictly accepts ISO8859-1 only, regardless of what encoding is

src/Message/Form/AuthorizeRequest.php

@@ -93,13 +93,6 @@ public function getCryptData()
     {
         $data = $this->getBaseAuthorizeData();
 
-        // CHECKME: are tokens supported?
-
-        if ($this->getToken() || $this->getCardReference()) {
-            // If using a token, then set that data.
-            $data = $this->getTokenData($data);
-        }
-
         // Some [optional] parameters specific to Sage Pay Form..
 
         if ($this->getCustomerName() !== null) {
@@ -144,7 +137,7 @@ public function getCryptData()
         $data = array_intersect_key($data, $this->validFields);
 
         // Throw exception if any mandatory fields are missing.
-        // We need to catch it here before sending the user to an
+        // We need to catch it here before sending the user to a
         // generic (and useless) error on the gateway site.
 
         foreach ($this->validFields as $fieldName => $mandatoryFlag) {