module Jekyll
  class ImageTag < Liquid::Tag

    def initialize(tag_name, parameters, tokens)
      super
      @params = {}
      parameters.scan(/(\w+)\s*=\s*"([^"]+)"/) do |key, value|
        @params[key] = value
      end
    end

    def render(context)
      url = @params['url']
      alt = @params['alt']
      if alt
        "<img src='#{url}' alt='#{alt}' />"
      else
        "<img src='#{url}' />"
      end
    end
    Liquid::Template.register_tag('image', self)
  end
end