class Images

def run
  @html.css('img').each do |i|
    img = Image.new i, "image", self
    # screenshot filenames should return because of terrible names
    next self.add_issue "image has a terrible filename (#{img.src})" if img.terrible_filename?
    # does the image exist?
    if img.missing_src?
      self.add_issue "image has no src attribute"
    elsif img.remote?
      next if img.ignore?
      add_to_external_urls img.src
    else
      next if img.ignore?
      self.add_issue("internal image #{img.src} does not exist") unless img.exists?
    end
    # check alt tag
    self.add_issue "image #{img.src} does not have an alt attribute" unless img.valid_alt_tag?
  end
  external_urls
end