small fix

Author: Iankumu

README.md

@@ -65,11 +65,17 @@ return [
     'passkey' => env('SAFARICOM_PASSKEY', 'bfb279f9aa9bdbcf158e97dd71a467cd2e0c893059b10f78e6b72ada1ed2c919'),
 
     /*-----------------------------------------
-        |The Lipa na Mpesa Online ShortCode (Paybill or Till Number)
+        |The Lipa na Mpesa Online ShortCode (Paybill Number)
         |------------------------------------------
         */
     'shortcode' => env('MPESA_BUSINESS_SHORTCODE', '174379'),
 
+    /*--------------------------------------------------------------
+        |The Lipa na Mpesa Online ShortCode  (Till Number)
+        |-----------------------------------------------------------
+    */
+    'till_number' => env('MPESA_BUY_GOODS_TILL', '174379'),
+
     /*-----------------------------------------
         |The Mpesa Initator Name
         |------------------------------------------

USAGE.md

@@ -80,11 +80,10 @@ return $result;
 
 ### Till Number Example
 
-To initiate a `Till Number (Buy Goods)` STK Push, call `stkpush()` with `$transactionType = Mpesa::TILL`.
+To initiate a `Till Number (Buy Goods)` STK Push, call `stkpush()` with `$transactionType = Mpesa::TILL` and ensure you set a till number in `config/mpesa.php`.
 Note these points:
 
 - Use a Till Number shortcode (not a PayBill shortcode).
-
 - Do not supply an accountNumber for Till flows
 
 ```php

config/mpesa.php

@@ -23,11 +23,17 @@
     'passkey' => env('SAFARICOM_PASSKEY', 'bfb279f9aa9bdbcf158e97dd71a467cd2e0c893059b10f78e6b72ada1ed2c919'),
 
     /*--------------------------------------------------------------
-        |The Lipa na Mpesa Online ShortCode (Paybill or Till Number)
+        |The Lipa na Mpesa Online ShortCode (Paybill Number)
         |-----------------------------------------------------------
     */
     'shortcode' => env('MPESA_BUSINESS_SHORTCODE', '174379'),
 
+    /*--------------------------------------------------------------
+        |The Lipa na Mpesa Online ShortCode  (Till Number)
+        |-----------------------------------------------------------
+    */
+    'till_number' => env('MPESA_BUY_GOODS_TILL', '174379'),
+
     /*-----------------------------------------
         |The Mpesa Initator Name
         |------------------------------------------

src/Mpesa.php

@@ -26,6 +26,13 @@ class Mpesa
      */
     public $shortcode;
 
+    /**
+     * The Lipa Na MPesa till number
+     *
+     * @var int
+     */
+    public $till_number;
+
     /**
      * The Mpesa B2C shortcode
      *
@@ -57,6 +64,7 @@ public function __construct()
 
         $this->security_credential = $this->generate_security_credential();
         $this->shortcode = $this->getConfig('shortcode');
+        $this->till_number = $this->getConfig('till_number');
         $this->initiator_name = $this->getConfig('initiator_name');
         $this->b2c_shortcode = $this->getConfig('b2c_shortcode');
     }
@@ -76,10 +84,6 @@ public function __construct()
     public function stkpush($phonenumber, $amount, $account_number = null, $callbackurl = null, $transactionType = self::PAYBILL)
     {
 
-        if ($transactionType === self::PAYBILL && empty($account_number)) {
-            throw new \InvalidArgumentException('Account number is required for Pay Bill transactions.');
-        }
-
         $validTypes = [self::PAYBILL, self::TILL];
         if (! in_array($transactionType, $validTypes, true)) {
             throw new \InvalidArgumentException(
@@ -88,14 +92,22 @@ public function stkpush($phonenumber, $amount, $account_number = null, $callback
             );
         }
 
+        if ($transactionType === self::PAYBILL && empty($account_number)) {
+            throw new \InvalidArgumentException('Account number is required for Pay Bill transactions.');
+        }
+
+        if ($transactionType === self::TILL && (empty($this->till_number) || is_null($this->till_number))) {
+            throw new \InvalidArgumentException('Till number is required for Buy Goods transactions.');
+        }
+
         $url = $this->url . '/mpesa/stkpush/v1/processrequest';
         $data = [
             'BusinessShortCode' => $this->shortcode, //Can be a paybill or till number
             'Password' => $this->LipaNaMpesaPassword(),
             'Timestamp' => $this->getFormattedTimeStamp(),
             'Amount' => (int) $amount,
             'PartyA' => $this->phoneValidator($phonenumber), // replace this with your phone number
-            'PartyB' => $this->shortcode,
+            'PartyB' => $transactionType == self::PAYBILL ? $this->shortcode : $this->till_number, //Can be a paybill or till number
             'TransactionType' => $transactionType, //Can be CustomerPayBillOnline or CustomerBuyGoodsOnline
             'PhoneNumber' => $this->phoneValidator($phonenumber), // replace this with your phone number
             'TransactionDesc' => 'Payment', //Maximum of 13 Characters.
@@ -279,7 +291,7 @@ public function c2bregisterURLS($shortcode, $confirmurl = null, $validateurl = n
      */
     public function c2bsimulate($phonenumber, $amount, $shortcode, $command_id, $account_number = null)
     {
-        if ($command_id == 'CustomerPayBillOnline') {
+        if ($command_id == self::PAYBILL) {
             //Paybill Request Body
             $data = [
                 'Msisdn' => $this->phoneValidator($phonenumber),