Remove highlighted html code while saving - highlight_file() php - php

Question

In my application I'm displaying the content of a file named test.php using ajax to a table with id fileContents. I'm using highlight_file() to highlight the code and it is working fine. I have a Save button in the page to save the div content back to the file.
<script language="JavaScript">
$( document ).ready(function() {
$.ajax({
url: 'test_file.php',
type: 'POST',
data: {
filePath: 'test.php'
},
success: function(data) {
$('#fileContents').html(data);
}
});
});
function saveFileContents() {
console.log($('#fileContentDiv').html());
}
</script>
<table id="fileContents">
</table>
<input type="button" value="Save" onclick="saveFileContents()">
test_file.php
<tr>
<td>
<div id="fileContentDiv" contenteditable="true">
<?php
echo highlight_file( $_POST['filePath'] );
?>
</td>
</tr>
test.php
<?php
echo "hai";
?>
I tried to edit the div and add a new line of code to the second last line $i=0; and when I click the Save button, I got console like this:
<code><span style="color: #000000">
<br><br><?php </span></code><div><code><span style="color: #000000">echo "hai";</span></code></div><div><code><span style="color: #000000">$i =0;</span></code></div><div><code><span style="color: #000000">?></span></code> </div>
I need to save the php code only back to the file(along with line breaks). I tried using $('#fileContent').text(). But it is saving the content in one line.
Can anyone help me to fix this? Thanks in advance.