From 433e169f06357eb7c9b43464b1a08624dcdf48bc Mon Sep 17 00:00:00 2001
From: Matt Pass <matt@mattpass.com>
Date: Sun, 6 Oct 2019 15:54:06 +0100
Subject: [PATCH] Lock off file from http, git diff -> MD5 to rescan

---
 processes/system.php | 49 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 41 insertions(+), 8 deletions(-)

diff --git a/processes/system.php b/processes/system.php
index f028d4d..7a044aa 100644
--- a/processes/system.php
+++ b/processes/system.php
@@ -1,12 +1,45 @@
 <?php
-// include("headers.php");
-// include("settings.php");
+// Only run internally on server, not from internet
+if (isset($_SERVER['HTTP_HOST'])) {
+    die("Server side script only");
+} else {
+    echo "Checking for changes via git diff every 2 secs...";
+}
+
+// Require a re-index dir/file data next time we index
+function requireReIndexNextTime() {
+        // If we have a data/index.php file
+        if (file_exists(dirname(__FILE__)."/../data/index.php")) {
+                // Get serialized array back out of PHP file inside a comment block as prevIndexData
+                $prevIndexData = file_get_contents(dirname(__FILE__)."/../data/index.php");
+                if (strpos($prevIndexData, "<?php") !== false) {
+                        $prevIndexData = str_replace("<?php\n/*\n\n", "", $prevIndexData);
+                        $prevIndexData = str_replace("\n\n*/\n?>", "", $prevIndexData);
+                        $prevIndexData = unserialize($prevIndexData);
+                        // Set timestamp back to epoch to force a re-index next time
+                        $prevIndexData['timestamps']['indexed'] = 0;
+                        file_put_contents(dirname(__FILE__)."/../data/index.php", "<?php\n/*\n\n".serialize($prevIndexData)."\n\n*/\n?".">");
+                }
+        }
+}
+
+// Run continuously
 while(true) {
-       $gitData = shell_exec("cd .. && { git diff --name-only --staged ; git ls-files --other --modified --exclude-standard ;} | sort | uniq");
-       $diffLines = explode("\n", $gitData);
-       $output = ["paths" => array_filter($diffLines)];
-       // Store the serialized array in PHP comment block for pick up
-       file_put_contents(dirname(__FILE__)."/../data/git-diff.php", "<?php\n/*\n\n".serialize($output)."\n\n*/\n?".">");
-       sleep(2);
+        // Get git diff output as a string and MD5 it as a checksum
+        $thisMD5 = shell_exec("cd .. && git diff | md5sum");
+        // If we have a previous checksum value and the current is different to it
+        if (isset($prevMD5) && $thisMD5 !== $prevMD5) {
+                // Set timestamp of last index to 0 to force a re-index next time we index
+                requireReIndexNextTime();
+                // Get a list of all that's changed, into an array (filtered to remove false entries)
+                $gitData = shell_exec("cd .. && { git diff --name-only --staged ; git ls-files --other --modified --exclude-standard ;} | sort | uniq");
+                $diffLines = explode("\n", $gitData);
+                $output = ["paths" => array_filter($diffLines)];
+                // Store the serialized array in PHP comment block for pick up
+                file_put_contents(dirname(__FILE__)."/../data/git-diff.php", "<?php\n/*\n\n".serialize($output)."\n\n*/\n?".">");
+                // Set prev MD5 to this one, ready for next time, sleep for 2 secs before loop starts again
+                $prevMD5 = $thisMD5;
+                sleep(2);
+        }
 }
 ?>