Custom view object

i18n_widgets.rb

# An encapsulated class for i18n-related widgets in the footer
#
# It includes:
#   - Locale switcher
#   - Currency switcher
#
# Also it's state stores available translated locales for current pages
#
class I18nWidgets

  delegate :params,
    :t, :content_tag, :link_to, :current_currency, # general helpers
    :root_path, :settings_update_path, # path helpers
    to: :@template

  # Sets a context for helpers and gets available locales for the record, if it's present
  #
  # @param template [ActionView] the context
  # @param record [ActiveRecord]
  #
  def initialize(template, record=nil)
    @template = template

    unless record.nil?
      # fallback to the default globalize method
      @available_locales = record.respond_to?(:available_locales) ? record.available_locales : record.translated_locales
    end
  end

  # Renders and concatenates locale and currency widgets
  def render
    render_locales + render_currencies
  end


  private

    # Renders locales switcher
    def render_locales
      wrapper(:locale) do
        Rails.application.config.i18n.available_locales.collect do |locale|
          if locale == I18n.locale
            content_tag :span, locale
          else
            locale_path = available_in?(locale) ? params.merge(locale: locale) : root_path(locale: locale)
            link_to locale.to_s, locale_path
          end
        end.join.html_safe
      end
    end

    # Renders currency switcher
    def render_currencies
      wrapper(:currency) do
        Rails.application.config.available_currencies.collect do |currency|
          if currency == current_currency.id
            content_tag :span, current_currency.symbol
          else
            link_to Money::Currency.find(currency).symbol, settings_update_path(currency: currency, locale: nil) unless current_currency.id == currency
          end
        end.join.html_safe
      end
    end

    # Checks if the current record is available in given locale.
    #
    # No need to check if translated_record is unset --> current action is always translated
    #
    # @param locale [Symbol]
    # @return [Boolean] availability
    #
    def available_in?(locale)
      @available_locales.nil? || @available_locales.include?(locale)
    end


    # Wraps i18n options into a common markup
    def wrapper(name)
      content_tag :div, class: "select-i18n select-i18n--#{name}" do
        t("shared.footer.#{name}").html_safe +
        content_tag(:div, class: 'select-i18n__options') do
          yield
        end
      end
    end

end