const HTTP_EQUIV = "http-equiv";
const REFRESH = "refresh";

const isHttpEquiv = ({attrs}) => HTTP_EQUIV in attrs && attrs[HTTP_EQUIV].toLowerCase() === REFRESH;

const filter = {
  "*": {itemtype: true},
  a: {href: true, ping: true},
  applet: {archive: true, code: true, codebase: true, object: true, src: true},
  area: {href: true, ping: true},
  audio: {src: true},
  base: {href: true},
  blockquote: {cite: true},
  body: {background: true},
  button: {formaction: true},
  del: {cite: true},
  embed: {src: true},
  form: {action: true},
  frame: {longdesc: true, src: true},
  head: {profile: true},
  html: {manifest: true},
  iframe: {longdesc: true, src: true},
  img: {longdesc: true, src: true, srcset: true},
  input: {formaction: true, src: true},
  ins: {cite: true},
  link: {href: true},
  menuitem: {icon: true},
  meta: {content: isHttpEquiv},
  module: {href: true},
  object: {codebase: true, data: true},
  q: {cite: true},
  script: {src: true},
  source: {src: true, srcset: true},
  table: {background: true},
  tbody: {background: true},
  td: {background: true},
  tfoot: {background: true},
  th: {background: true},
  thead: {background: true},
  tr: {background: true},
  track: {src: true},
  video: {poster: true, src: true}
}

module.exports = filter;