i18n aware haml and erb template loader for Sinatra

my haml override.

  helpers do
    def haml(template, options = {}, *)
      
      # template will either be the name of a template or the body of a template.
      # if it's the body then it will contain a "%" symbol and so we can skip any processing
      
      template_name = template.to_s
      
      do_not_localise = false
      if template_name.include?('%')
        # it's actually the template content we have here, not a template name
        super
      else
        # it's a template name we have here.
        # note layout.haml files must never hold untranslated text
        if template_name.include?('chunks/')
          options[:layout] ||= false
          do_not_localise = true
        elsif template_name.include?('mail/')
          options[:layout] ||= false
        elsif is_logged_in? || template_name.include?('in/')
          options[:layout] ||= :'in/layout'
        end

        # now if template_bits[0] is a locale code then just pass through
        if do_not_localise
          # "Don't bother localising chunks.
          super
        else
          # there is no locale code in front of the template name
          # now make an adjustment to the template path depending on locale.
          local_template_file = "views/#{r18n.locale.code.downcase}/#{template_name}.haml"
          if File.exists? local_template_file
            # Found a localised template so we'll use that one
            local_template = File.read(local_template_file)
            return haml(local_template, options)
          elsif r18n.locale.sublocales != nil && r18n.locale.sublocales.size > 0
            # Couldn't find a template for that specific locale.
            local_template_file = "views/#{r18n.locale.sublocales[0].downcase}/#{template_name}.haml"
            if File.exists? local_template_file
              # but there is a more generic language file so use that.
              # note if I really wanted to I could loop through in case sublocales[0] doesn't exist but other one does.
              # too complicated for now though and simply not needed.  TODO: polish this up later.
              local_template = File.read(local_template_file)
              return haml(local_template, options)
            else
              # No localsied version of this template exists. Okay use the template we were supplied.
              super
            end
          else
            # That locale has no sublocales so just use the template we were supplied.
            super
          end
        end
      end
    end

    def erb(template, options = {}, *)
      # template will either be the name of a template or the body of a template.
      # if it's the body then it will contain a "%" symbol and so we can skip any processing
      
      template_name = template.to_s
      
      if template_name.include?('%')
        # it's actually the template content we have here, not a template name
        super
      else
        # it's a template name we have here.

        # now make an adjustment to the template path depending on locale.
        local_template_file = "views/#{r18n.locale.code.downcase}/#{template_name}.erb"
        if File.exists? local_template_file
          # Found a localised template so we'll use that one
          local_template = File.read(local_template_file)
          return erb(local_template, options)
        elsif r18n.locale.sublocales != nil && r18n.locale.sublocales.size > 0
          # Couldn't find a template for that specific locale.
          local_template_file = "views/#{r18n.locale.sublocales[0].downcase}/#{template_name}.erb"
          if File.exists? local_template_file
            # but there is a more generic language file so use that.
            # note if I really wanted to I could loop through in case sublocales[0] doesn't exist but other one does.
            # too complicated for now though and simply not needed.  TODO: polish this up later.
            local_template = File.read(local_template_file)
            return erb(local_template, options)
          else
            # No localsied version of this template exists. Okay use the template we were supplied.
            super
          end
        else
          # That locale has no sublocales so just use the template we were supplied.
          super
        end
      end
    end
  end