module.exports = function(hljs) {
  var OPENING_LONG_BRACKET = '\\[=*\\[';
  var CLOSING_LONG_BRACKET = '\\]=*\\]';
  var LONG_BRACKETS = {
    begin: OPENING_LONG_BRACKET, end: CLOSING_LONG_BRACKET,
    contains: ['self']
  };
  var COMMENTS = [
    hljs.COMMENT('--(?!' + OPENING_LONG_BRACKET + ')', '$'),
    hljs.COMMENT(
      '--' + OPENING_LONG_BRACKET,
      CLOSING_LONG_BRACKET,
      {
        contains: [LONG_BRACKETS],
        relevance: 10
      }
    )
  ];
  return {
    lexemes: hljs.UNDERSCORE_IDENT_RE,
    keywords: {
      literal: "true false nil",
      keyword: "and break do else elseif end for goto if in local not or repeat return then until while",
      built_in:
        //Metatags and globals:
        '_G _ENV _VERSION __index __newindex __mode __call __metatable __tostring __len ' +
        '__gc __add __sub __mul __div __mod __pow __concat __unm __eq __lt __le assert ' +
        //Standard methods and properties:
        'collectgarbage dofile error getfenv getmetatable ipairs load loadfile loadstring' +
        'module next pairs pcall print rawequal rawget rawset require select setfenv' +
        'setmetatable tonumber tostring type unpack xpcall arg self' +
        //Library methods and properties (one line per library):
        'coroutine resume yield status wrap create running debug getupvalue' +
        'debug sethook getmetatable gethook setmetatable setlocal traceback setfenv getinfo setupvalue getlocal getregistry getfenv' +
        'io lines write close flush open output type read stderr stdin input stdout popen tmpfile' +
        'math, log, max, acos, huge, ldexp, pi, cos, tanh, pow, deg, tan, cosh, sinh, random, randomseed, frexp, ceil, floor, rad, abs, sqrt, modf, asin, min, mod, fmod, log10, atan2, exp, sin, atan' +
        'os, exit, setlocale, date, getenv, difftime, remove, time, clock, tmpname, rename, execute, package, preload, loadlib, loaded, loaders, cpath, config path, seeall' +
        'string, sub, upper, len, gfind, rep, find, match, char, dump, gmatch, reverse, byte, format, gsub, lower' +
        'table, setn, insert, getn, foreachi, maxn, foreach, concat, sort, remove'
    },
    contains: COMMENTS.concat([
      {
        className: 'function',
        beginKeywords: 'function', end: '\\)',
        contains: [
          hljs.inherit(hljs.TITLE_MODE, {begin: '([_a-zA-Z]\\w*\\.)*([_a-zA-Z]\\w*:)?[_a-zA-Z]\\w*'}),
          {
            className: 'params',
            begin: '\\(', endsWithParent: true,
            contains: COMMENTS
          }
        ].concat(COMMENTS)
      },
      hljs.C_NUMBER_MODE,
      hljs.APOS_STRING_MODE,
      hljs.QUOTE_STRING_MODE,
      {
        className: 'string',
        begin: OPENING_LONG_BRACKET, end: CLOSING_LONG_BRACKET,
        contains: [LONG_BRACKETS],
        relevance: 5
      }
    ])
  };
};