class Middleman::ExtensionManager

def initialize(app)
  @app = app
  @activated = {}
  ::Middleman::Extensions.load_settings(@app)
  manager = self
  {
    before_sitemap: :before_sitemap,
    initialized: :before_configuration
  }.each do |key, value|
    cb = proc { manager.auto_activate(value) }
    @app.send(key, &cb)
  end
  @app.after_configuration_eval(&method(:activate_all))
end