diff --git a/src/PaypalIPN.php b/src/PaypalIPN.php
index b4f1561..7f510ed 100644
--- a/src/PaypalIPN.php
+++ b/src/PaypalIPN.php
@@ -1,20 +1,15 @@
-<?php 
+<?php
 
 namespace overint;
 
-use \Exception
+use \Exception;
 
 class PaypalIPN
 {
-
-    /**
-     * @var bool $use_sandbox     Indicates if the sandbox endpoint is used.
-     */
-    private $use_sandbox = false;
-    /**
-     * @var bool $use_local_certs Indicates if the local certificates are used.
-     */
-    private $use_local_certs = true;
+    /** @var bool $useSandbox Indicates if the sandbox endpoint is used. */
+    private $useSandbox = false;
+    /** @var bool $useLocalCerts Indicates if the local certificates are used. */
+    private $useLocalCerts = true;
 
     /** Production Postback URL */
     const VERIFY_URI = 'https://ipnpb.paypal.com/cgi-bin/webscr';
@@ -35,7 +30,7 @@ class PaypalIPN
      */
     public function useSandbox()
     {
-        $this->use_sandbox = true;
+        $this->useSandbox = true;
     }
 
     /**
@@ -45,7 +40,7 @@ public function useSandbox()
      */
     public function usePHPCerts()
     {
-        $this->use_local_certs = false;
+        $this->useLocalCerts = false;
     }
 
 
@@ -55,7 +50,7 @@ public function usePHPCerts()
      */
     public function getPaypalUri()
     {
-        if ($this->use_sandbox) {
+        if ($this->useSandbox) {
             return self::SANDBOX_VERIFY_URI;
         } else {
             return self::VERIFY_URI;
@@ -72,23 +67,18 @@ public function getPaypalUri()
      */
     function verifyIPN()
     {
-        if ( ! count($_POST))
-        {
+        if (!count($_POST)) {
             throw new Exception("Missing POST Data");
         }
 
         $raw_post_data = file_get_contents('php://input');
         $raw_post_array = explode('&', $raw_post_data);
         $myPost = [];
-        foreach ($raw_post_array as $keyval)
-        {
+        foreach ($raw_post_array as $keyval) {
             $keyval = explode('=', $keyval);
-            if (count($keyval) == 2)
-            {
-                if ($keyval[0] === 'payment_date')
-                {
-                    if (substr_count($keyval[1], '+') === 1)
-                    {
+            if (count($keyval) == 2) {
+                if ($keyval[0] === 'payment_date') {
+                    if (substr_count($keyval[1], '+') === 1) {
                         $keyval[1] = str_replace('+', '%2B', $keyval[1]);
                     }
                 }
@@ -97,17 +87,13 @@ function verifyIPN()
         }
         $req = 'cmd=_notify-validate';
         $get_magic_quotes_exists = false;
-        if (function_exists('get_magic_quotes_gpc'))
-        {
+        if (function_exists('get_magic_quotes_gpc')) {
             $get_magic_quotes_exists = true;
         }
-        foreach ($myPost as $key => $value)
-        {
-            if ($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1)
-            {
+        foreach ($myPost as $key => $value) {
+            if ($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1) {
                 $value = urlencode(stripslashes($value));
-            } else
-            {
+            } else {
                 $value = urlencode($value);
             }
             $req .= "&$key=$value";
@@ -121,35 +107,30 @@ function verifyIPN()
         curl_setopt($ch, CURLOPT_SSLVERSION, 6);
         curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
         curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
-        if ($this->use_local_certs)
-        {
+        if ($this->useLocalCerts) {
             curl_setopt($ch, CURLOPT_CAINFO, __DIR__ . "/cert/cacert.pem");
         }
         curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
         curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
-        curl_setopt($ch, CURLOPT_HTTPHEADER, [ 'Connection: Close' ]);
+        curl_setopt($ch, CURLOPT_HTTPHEADER, ['Connection: Close']);
         $res = curl_exec($ch);
         $info = curl_getinfo($ch);
         $http_code = $info['http_code'];
 
-        if ($http_code != 200)
-        {
+        if ($http_code != 200) {
             throw new Exception("PayPal responded with http code $http_code");
         }
 
-        if ( ! ( $res ))
-        {
+        if (!($res)) {
             $errno = curl_errno($ch);
             $errstr = curl_error($ch);
             curl_close($ch);
             throw new Exception("cURL error: [$errno] $errstr");
         }
         curl_close($ch);
-        if ($res == self::VALID)
-        {
+        if ($res == self::VALID) {
             return true;
-        } else
-        {
+        } else {
             return false;
         }
     }