How to dynamically apply classes to objects in ember-cli?

I'm creating an app that has a listing of items and a series of filter buttons at the top. As the user applies different filters, I want the buttons to change style using CSS classes to show them as enabled/disabled.

I want to be able to write something like the code below, but it doesn't work.

{{#each category in category_options}}
  <button {{action "filterCategory" category}} {{bind-attr class=":btn-small isFiltered(category):btn-active:btn-inactive"}}>{{category}}</button>
{{/each}}

In this example, isFiltered is a computed property on the controller, and it looks at the query parameters to determine whether the specified category has been applied as a filter.

From the reading I've done, it sounds like you can't pass parameters to computed properties. I've come across answers mentioning helpers, bound helpers, and components, but I haven't been able to sort out which one I need, or how I would apply it in this situation.