Javascript back-link code inside PHP IF condition

Question

I'm using the following Javascript code for (browser) Back-link URL:

<script type="text/javascript">
    history.pushState(null, null, '<?php echo $_SERVER["REQUEST_URI"]; ?>');

    window.addEventListener('popstate', function(event)
    {
        window.location.assign("https://backlink.com");
    });
</script>

And I would like to put it inside:

<?php
if( strpos( $source, 'abc' ) !== false ) {
    Javascript code should go here
}
?>

I tried it in different ways but always got Syntax error. Can somebody help?

Thanks

Answer 1

As noted in the comments doing something like this is generally considered a bad idea but this should accomplish what you are trying to do.

if( strpos( $source, 'abc' ) !== false ) {
    echo '<script type="text/javascript">
    history.pushState(null, null, "' . $_SERVER["REQUEST_URI"] . '"
    window.addEventListener("popstate", function(event)
    {
        window.location.assign("https://backlink.com");
    });
</script>}';
}