Knockout.js syntax highlighting in HTML data-bind attributes?

So far I haven't been able to find any support for Knockout.js in IDEA, except including it as a library. HTML files have highlighting and completion for JavaScript in onclick attributes for instance. I would like to have the same for data-bind attributes, including some variables specific to Knockout ($data, $parent and other context variables).

Writing a plugin for this didn't seem too complicated, but I got lost in the vast jungle of Java-classes. Do I have to create a new custom language?

Support for virtual elements (ko comments) would also be nice, the syntax is similar to the data-bind attributes.