sessions_controller.rb

class SessionsController < ApplicationController
  def update
    update_cookie :crns
    update_cookie :section_ids
    update_cookie :semester_id

    head :ok
  end

  def cart
    section_id = params[:section_id]

    if @cart.include?(section_id)
      @cart.reject! { |id| section_id == id }
    else
      @cart << section_id
    end

    puts @cart.to_json
    cookies[:cart] = @cart.to_json
    render json: @cart.to_json
  end

  private

  def update_cookie(sym)
    cookies[sym] = params[sym] unless params[sym].nil?
  end
end