module Lita
  module Handlers
    class Zerocater < Handler
      config :locations, type: Hash, required: true

      route(
        /^zerocater\stoday$/,
        :today,
        command: true,
        help: {
          t('help.today.syntax') => t('help.today.desc')
        }
      )

      route(
        /^zerocater\stomorrow$/,
        :tomorrow,
        command: true,
        help: {
          t('help.tomorrow.syntax') => t('help.tomorrow.desc')
        }
      )

      route(
        /^zerocater\syesterday$/,
        :yesterday,
        command: true,
        help: {
          t('help.yesterday.syntax') => t('help.yesterday.desc')
        }
      )

      route(
        /^lunch$/,
        :today,
        command: true,
        help: {
          t('help.lunch.syntax') => t('help.lunch.desc')
        }
      )

      def today(response)
        config.locations.keys.each do |location|
          response.reply(menu_today(location))
        end
      end

      def tomorrow(response)
        config.locations.keys.each do |location|
          response.reply(menu_tomorrow(location))
        end
      end

      def yesterday(response)
        config.locations.keys.each do |location|
          response.reply(menu_yesterday(location))
        end
      end

      private

      def fetch(location)
        http.get('https://zerocater.com/m/' + location)
      end

      def extract(menu_text, search_date)
        # NOTE: This is horrible.  No, really.  Curse you Zerocater.
        results = []
        page = Nokogiri::HTML(menu_text.body)
        menu = page.css("div.menu[data-date='" + search_date + "']")
        menu.css('.meal-label').each do |meal|
          meal.css('.order-name').each do |order|
            results.push order.text.strip.to_ascii
          end
        end
        results
      end

      # rubocop:disable Metrics/AbcSize
      # rubocop:disable Metrics/MethodLength
      def menu(location, search_date)
        cache_key = "#{location}_#{search_date}"
        return redis.get(cache_key) if redis.exists(cache_key)

        begin
          menu = extract(fetch(config.locations[location]), search_date)
        rescue
          return t('error.retrieve')
        end

        return t('error.empty') unless menu.size > 0

        t = render_template('menu',
                            menu: menu,
                            locale: t('menu.locale', location: location))
        redis.set(cache_key, t)
        t
      end
      # rubocop:enable Metrics/AbcSize
      # rubocop:enable Metrics/MethodLength

      def menu_today(location)
        menu(location, (Date.today).to_s)
      end

      def menu_yesterday(location)
        menu(location, (Date.today - 1).to_s)
      end

      def menu_tomorrow(location)
        menu(location, (Date.today + 1).to_s)
      end
    end

    Lita.register_handler(Zerocater)
  end
end