PHP footer display file time stamp - php

Question

For each page I am coding I have a foot that I use php include "footer.php" in all of them. Below is the foot.php code. I need my code to be able to give the correct time stamp for each file not one speific file. So in the end each page should have a different time stamp because I am workign on each file at different times becasue the website I am making is for a class assignments. And of course each assignment is being coded at on different days. If this doesn't make since let me know.
<footer align="center">
<hr width="900px" size="2" noshade="noshade" color="black" align="center">
<div style="padding:0 30px">
<p>Validated by:</p>
<img src="https://www.w3.org/Icons/valid-xhtml11" alt="Valid XHTML 1.1" height="31" width="88">
<img src="https://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS">
<p>Last modified:
<?php
$timestamp = filemtime(__FILE__);
$date_time = new DateTime();
$date_time->setTimezone(new DateTimeZone("America/New_York"));
$date_time->setTimestamp($timestamp);
echo $date_time->format("F j Y g:i a.");
?>
</p>
</div>
</footer>
I asked for help on this before but not working out.

Answer 1

First we need a function that reads all files of a folder in an association
reads out the timestamp values
function getFileModificationTimes(string $directory): array {
$files = scandir($directory);
$modificationTimes = [];
foreach ($files as $file) {
if ($file === '.' || $file === '..') {
continue;
}
$path = $directory . '/' . $file;
if (!is_file($path)) {
continue;
}
$modificationTimes[$file] = filemtime($path);
}
return $modificationTimes;
}
and a second function that determines the largest/most recent value
function getMaxModificationTime(array $modificationTimes) {
$maxModificationTime = 0;
$maxFile = '';
foreach ($modificationTimes as $file => $modificationTime) {
if ($modificationTime > $maxModificationTime) {
$maxModificationTime = $modificationTime;
$maxFile = $file;
}
}
return [$maxFile, $maxModificationTime];
}
the footer now shows the date of the newest file from the folder
<?php
$modificationTimes = getFileModificationTimes('/path/to/directory');
list($maxFile, $maxModificationTime) = getMaxModificationTime($modificationTimes);
?>
<footer align="center">
<hr width="900px" size="2" noshade="noshade" color="black" align="center">
<div style="padding:0 30px">
<p>Validated by:</p>
<img src="https://www.w3.org/Icons/valid-xhtml11" alt="Valid XHTML 1.1" height="31" width="88">
<img src="https://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS">
<p>The file with the most recent modification time is <?=$maxFile?>, which was modified at <?=date('Y-m-d H:i:s', $maxModificationTime)?>.
</p>
</div>
</footer>

Answer 2

If you want to show the modification time of the file including the footer, then remove $timestamp = filemtime(__FILE__); from the footer file and put it before the include().
Eg:
$timestamp = filemtime(__FILE__);
include('footer.php');