From 749e079645be60dc0711817ca6d262a8a35f3ddf Mon Sep 17 00:00:00 2001
From: Ulf Gebhardt <ulf.gebhardt@webcraft-media.de>
Date: Thu, 30 Mar 2017 15:35:25 +0200
Subject: [PATCH] fixed system header transmit to match google criteria

---
 files/files.php   | 1 +
 system/HEADER.php | 9 +++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/files/files.php b/files/files.php
index bd84f96..0c02c43 100644
--- a/files/files.php
+++ b/files/files.php
@@ -52,6 +52,7 @@ class files {
 
         $ext = pathinfo(self::$folders[$cat].$id);
         $ext = strtoupper(array_key_exists('extension', $ext) ? $ext['extension'] : '');
+        header("Last-Modified: " . gmdate('D, d M Y H:i:s \G\M\T', filemtime(self::$folders[$cat].$id)));
         if(\SYSTEM\HEADER::available($ext)){
             call_user_func('\SYSTEM\HEADER::'.$ext);
         }else{
diff --git a/system/HEADER.php b/system/HEADER.php
index 0e4199a..50e6cbb 100644
--- a/system/HEADER.php
+++ b/system/HEADER.php
@@ -56,7 +56,7 @@ class HEADER {
      */
     public static function PNG(){
         if(self::checkHeader()){
-            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60))); // 1 hour
+            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60 * 24 * 7))); // 1 week
             header('content-type:image/png;');}}
     /**
      * Send JPG Headers, if Header was not sent yet
@@ -65,7 +65,7 @@ class HEADER {
      */
     public static function JPG(){
         if(self::checkHeader()){
-            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60))); // 1 hour
+            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60 * 24 * 7))); // 1 week
             header('content-type:image/jpeg;');}}
     /**
      * Send JPEG Headers, if Header was not sent yet
@@ -74,7 +74,7 @@ class HEADER {
      */
     public static function JPEG(){
         if(self::checkHeader()){
-            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60))); // 1 hour
+            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60 * 24 * 7))); // 1 week
             header('content-type:image/jpeg;');}}   
     /**
      * Send GIF Headers, if Header was not sent yet
@@ -83,7 +83,7 @@ class HEADER {
      */
     public static function GIF(){
         if(self::checkHeader()){
-            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60))); // 1 hour
+            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60 * 24 * 7))); // 1 week
             header('content-type:image/gif;');}}  
     /**
      * Send JS Headers, if Header was not sent yet
@@ -100,6 +100,7 @@ class HEADER {
      */
     public static function CSS(){
         if(self::checkHeader()){
+            header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + (60 * 60 * 24 * 7))); // 1 week
             header('content-type:text/css;');}}
     /**
      * Send LESS Headers, if Header was not sent yet