module Jekyll
  class EnunciationTagBlock < Liquid::Block

    def initialize(tag_name, arg, parse_context)
      super
      @arg = arg.strip
      @slugtemplate = Liquid::Template.parse("{{ string | slugify }}")
    end

    def render(context)
      text = super
      # If the enunciation ends with a KaTeX displayed equation,
      # then we remove the bottom margin.
      if text[-5,5] == "  $$\n"
        text += '  {: .katex-display .mb-0 }'
      elsif text[-3,3] == "$$\n"
        text += '{: .katex-display .mb-0 }'
      end
      # Check if a description was given.
      if @arg.length < 1
        "{: .#{block_name} }\n #{text.gsub!(/^/,'> ')}"
      else
        if @arg[0] == "*"
          title = @arg.delete_prefix("* ")
        else
          title = "#{block_name.capitalize} (#{@arg})"
        end
        slug = @slugtemplate.render( 'string' => title )
        "{: .#{block_name}-title }\n> #{title}\n> {: \##{slug} }\n>\n#{text.gsub!(/^/,'> ')}"
      end
    end

  end
end

# TODO: avoid reading configuration twice
Jekyll.configuration({})['callouts'].each do |name, value|
  Liquid::Template.register_tag(name, Jekyll::EnunciationTagBlock)
end