jekyll-icon-tag.rb

# frozen_string_literal: true

module Jekyll
  module Tags

    # Our {% icon X %} tag
    class IconTag < Liquid::Tag
      def initialize(tag_name, text, tokens)
        super
        parts = text.strip.split
        @text = parts[0]
        @aria = true
        return unless parts[1] == 'aria=false'

        @aria = false
      end

      ##
      # This function renders the icon tag
      # Params:
      # +icon+:: The icon to render
      # +@area+:: Whether to add aria-hidden
      # +@text+:: The text to add to the icon
      #
      # Returns:
      # The HTML for the icon
      # Note: The icon text label is wrapped in a span with class
      #       "visually-hidden" to make it accessible to screen readers.
      #
      # Example:
      #  {% icon fa fa-github %}
      #  => <i class="fa fa-github" aria-hidden="true"></i>
      #  {% icon fa fa-github aria=false %}
      #  => <i class="fa fa-github"></i>
      def render_for_text(icon)
        if icon.empty?
          raise SyntaxError, "No icon defined for: '#{@text}'. Please define it in `_config.yml` (under `icon-tag:`)."
        end

        if icon.start_with?('fa')
          if @aria
            %(<i class="#{icon}" aria-hidden="true"></i><span class="visually-hidden">#{@text}</span>)
          else
            %(<i class="#{icon}" aria-hidden="true"></i>)
          end
        elsif icon.start_with?('ai')
          if @aria
            %(<i class="ai #{icon}" aria-hidden="true"></i><span class="visually-hidden">#{@text}</span>)
          else
            %(<i class="ai #{icon}" aria-hidden="true"></i>)
          end
        end
      end

      ##
      # icon - Include an icon from our _config.yml into your tutorial
      #
      # Examples:
      #
      #   {% icon email %}
      #   {% icon galaxy-history %}
      #
      def render(context)
        cfg = get_config(context)
        icon = cfg[@text] || ''
        render_for_text(icon)
      end

      def get_config(context)
        context.registers[:site].config['icon-tag']
      end
    end

    # The variable version that can accept a variable name instead of a string
    class IconTagVar < IconTag
      def initialize(tag_name, text, tokens)
        super
        @text = text.strip
      end

      ##
      # icon_var - Include an icon from our _config.yml into your tutorial, but accessing a variable rather than expecting a string.
      #
      # Examples:
      #
      #   {% icon_var var1 %}
      #   {% icon_var var2 %}
      #
      def render(context)
        cfg = get_config(context)
        icon = cfg[context[@text]] || ''
        render_for_text(icon)
      end
    end
  end
end

Liquid::Template.register_tag('icon_var', Jekyll::Tags::IconTagVar)
Liquid::Template.register_tag('icon', Jekyll::Tags::IconTag)