(function (Prism) {
  var parser = (Prism.languages.parser = Prism.languages.extend('markup', {
    keyword: {
      pattern:
        /(^|[^^])(?:\^(?:case|eval|for|if|switch|throw)\b|@(?:BASE|CLASS|GET(?:_DEFAULT)?|OPTIONS|SET_DEFAULT|USE)\b)/,
      lookbehind: true,
    },
    variable: {
      pattern: /(^|[^^])\B\$(?:\w+|(?=[.{]))(?:(?:\.|::?)\w+)*(?:\.|::?)?/,
      lookbehind: true,
      inside: {
        punctuation: /\.|:+/,
      },
    },
    function: {
      pattern: /(^|[^^])\B[@^]\w+(?:(?:\.|::?)\w+)*(?:\.|::?)?/,
      lookbehind: true,
      inside: {
        keyword: {
          pattern: /(^@)(?:GET_|SET_)/,
          lookbehind: true,
        },
        punctuation: /\.|:+/,
      },
    },
    escape: {
      pattern: /\^(?:[$^;@()\[\]{}"':]|#[a-f\d]*)/i,
      alias: 'builtin',
    },
    punctuation: /[\[\](){};]/,
  }));

  parser = Prism.languages.insertBefore('parser', 'keyword', {
    'parser-comment': {
      pattern: /(\s)#.*/,
      lookbehind: true,
      alias: 'comment',
    },
    expression: {
      // Allow for 3 levels of depth
      pattern: /(^|[^^])\((?:[^()]|\((?:[^()]|\((?:[^()])*\))*\))*\)/,
      greedy: true,
      lookbehind: true,
      inside: {
        string: {
          pattern: /(^|[^^])(["'])(?:(?!\2)[^^]|\^[\s\S])*\2/,
          lookbehind: true,
        },
        keyword: parser.keyword,
        variable: parser.variable,
        function: parser.function,
        boolean: /\b(?:false|true)\b/,
        number: /\b(?:0x[a-f\d]+|\d+(?:\.\d*)?(?:e[+-]?\d+)?)\b/i,
        escape: parser.escape,
        operator:
          /[~+*\/\\%]|!(?:\|\|?|=)?|&&?|\|\|?|==|<[<=]?|>[>=]?|-[fd]?|\b(?:def|eq|ge|gt|in|is|le|lt|ne)\b/,
        punctuation: parser.punctuation,
      },
    },
  });

  Prism.languages.insertBefore(
    'inside',
    'punctuation',
    {
      expression: parser.expression,
      keyword: parser.keyword,
      variable: parser.variable,
      function: parser.function,
      escape: parser.escape,
      'parser-punctuation': {
        pattern: parser.punctuation,
        alias: 'punctuation',
      },
    },
    parser['tag'].inside['attr-value']
  );
})(Prism);