BASENAME="$1"
EXTENSION="${BASENAME##*.}"

[ "${BASENAME}" = "${EXTENSION}" ] && EXTENSION=txt
[ -z "${EXTENSION}" ] && EXTENSION=txt

# map Makefile and Makefile.* to .mk
[ "${BASENAME%%.*}" = "Makefile" ] && EXTENSION=mk


cat << EOF
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.11.1/styles/default.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.11.1/highlight.min.js"></script>

<!-- and it's easy to individually load additional languages -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.11.1/languages/go.min.js"></script>
<pre><code class="language-$EXTENSION">
EOF

cat

cat << EOF 
</code></pre>
<script>hljs.highlightAll();</script>
EOF