module Mustache::Sinatra::Helpers

def mustache(template, options={}, locals={})
  render :mustache, template, options, locals
end

def render_mustache(template, data, opts, locals, &block)
  # If you have Hurl::App::Views, namespace should be set to Hurl::App.
  Mustache.view_namespace = options.namespace
  # This is probably the same as options.views, but we'll set it anyway.
  # It's used to tell Mustache where to look for view classes.
  Mustache.view_path = options.mustaches
  # Grab the class!
  klass = Mustache.view_class(template)
  # Only cache the data if this isn't the generic base class.
  klass.template = data unless klass == Mustache
  # Confusingly Sinatra's `views` setting tells Mustache where the
  # templates are found. It's fine, blame Chris.
  if klass.template_path != options.views
    klass.template_path = options.views
  end
  # Create a new instance for playing with
  instance = klass.new
  # Copy instance variables set in Sinatra to the view
  instance_variables.each do |name|
    instance.instance_variable_set(name, instance_variable_get(name))
  end
  # Locals get added to the view's context
  locals.each do |local, value|
    instance[local] = value
  end
  # If we're paseed a block it's a subview. Sticking it in yield
  # lets us use {{yield}} in layout.html to render the actual page.
  instance[:yield] = block.call if block
  instance.template = data unless instance.compiled?
  instance.to_html
end