module Trestle
  class Hook
    module Helpers
      def hook(name, *args, &block)
        hooks = hooks(name)

        if hooks.any?
          safe_join(hooks.map { |hook|
            hook.evaluate(self, *args)
          }, "\n")
        elsif block_given?
          capture(*args, &block)
        end
      end

      def hook?(name)
        hooks(name).any?
      end

    protected
      def hooks(name)
        hook_sets.map { |set| set.for(name) }.inject(&:+).select { |h| h.visible?(self) }
      end

      def hook_sets
        @_hook_sets ||= [
          (admin.hooks if defined?(admin) && admin),
          Trestle.config.hooks
        ].compact
      end
    end
  end
end