1 files changed, 56 insertions, 0 deletions
diff --git a/lib/output/modifiers/highlightCode.js b/lib/output/modifiers/highlightCode.js
new file mode 100644
index 0000000..dcd9d24
--- /dev/null
+++ b/lib/output/modifiers/highlightCode.js
@@ -0,0 +1,56 @@
+var is = require('is');
+var Promise = require('../../utils/promise');
+var editHTMLElement = require('./editHTMLElement');
+
+/**
+    Return language for a code blocks from a list of class names
+
+    @param {Array<String>}
+    @return {String}
+*/
+function getLanguageForClass(classNames) {
+    return classNames
+        .map(function(cl) {
+            // Markdown
+            if (cl.search('lang-') === 0) {
+                return cl.slice('lang-'.length);
+            }
+
+            // Asciidoc
+            if (cl.search('language-') === 0) {
+                return cl.slice('language-'.length);
+            }
+
+            return null;
+        })
+        .find(function(cl) {
+            return Boolean(cl);
+        });
+}
+
+
+/**
+    Highlight all code elements
+
+    @param {Function(lang, body) -> String} highlight
+    @param {HTMLDom} $
+    @return {Promise}
+*/
+function highlightCode(highlight, $) {
+    return editHTMLElement($, 'code', function($code) {
+        var classNames = ($code.attr('class') || '').split(' ');
+        var lang = getLanguageForClass(classNames);
+        var source = $code.text();
+
+        return Promise(highlight(lang, source))
+        .then(function(r) {
+            if (is.string(r.html)) {
+                $code.html(r.html);
+            } else {
+                $code.text(r.text);
+            }
+        });
+    });
+}
+
+module.exports = highlightCode;