offers_controller_create.rb

  # POST /offers
  # POST /offers.json
  def create
    @offer                 = Offer.new(offer_params)
    @offer.offer_timestamp = Time.zone.now
    @offer.user            = current_user

    respond_to do |format|
      if @offer.save
        format.html { redirect_to [@offer.product, @offer], notice: 'Offer was successfully created.' }
        format.json { render json: @offer, status: :created, location: [@offer.product, @offer] }
      else
        # This looks ugly
        @product = @offer.product
        @offers  = @product.offers
        format.html { render action: :index }
        format.json { render json: @offer.errors, status: :unprocessable_entity }
      end
    end
  end