(function () {

function forEach(arr, f) {
  for (var i = 0, e = arr.length; i < e; ++i) f(arr[i]);
}

function arrayContains(arr, item) {
  if (!Array.prototype.indexOf) {
    var i = arr.length;
    while (i--) {
      if (arr[i] === item) {
        return true;
      }
    }
    return false;
  }
  return arr.indexOf(item) != -1;
}

function scriptHint(editor, keywords, getToken, options) {
  // Find the token at the cursor
  var cur = editor.getCursor(), token = getToken(editor, cur), tprop = token;
  // If it's not a 'word-style' token, ignore the token.
              if (!/^[\w$_]*$/.test(token.string)) {
    token = tprop = {start: cur.ch, end: cur.ch, string: "", state: token.state,
                     className: token.string == "." ? "property" : null};
  }
  // If it is a property, find out what it is a property of.
  while (tprop.className == "property") {
    tprop = getToken(editor, {line: cur.line, ch: tprop.start});
    if (tprop.string != ".") return;
    tprop = getToken(editor, {line: cur.line, ch: tprop.start});
    if (tprop.string == ')') {
      var level = 1;
      do {
        tprop = getToken(editor, {line: cur.line, ch: tprop.start});
        switch (tprop.string) {
        case ')': level++; break;
        case '(': level--; break;
        default: break;
        }
      } while (level > 0);
      tprop = getToken(editor, {line: cur.line, ch: tprop.start});
                              if (tprop.className == 'variable')
                                      tprop.className = 'function';
                              else return; // no clue
    }
    if (!context) var context = [];
    context.push(tprop);
  }
  return {list: getCompletions(token, context, keywords, options),
          from: {line: cur.line, ch: token.start},
          to: {line: cur.line, ch: token.end}};
}

CodeMirror.javascriptHint = function(editor, options) {
  return scriptHint(editor, javascriptKeywords,
                    function (e, cur) {return e.getTokenAt(cur);},
                    options);
};

function getCoffeeScriptToken(editor, cur) {
// This getToken, it is for coffeescript, imitates the behavior of
// getTokenAt method in javascript.js, that is, returning "property"
// type and treat "." as indepenent token.
  var token = editor.getTokenAt(cur);
  if (cur.ch == token.start + 1 && token.string.charAt(0) == '.') {
    token.end = token.start;
    token.string = '.';
    token.className = "property";
  }
  else if (/^\.[\w$_]*$/.test(token.string)) {
    token.className = "property";
    token.start++;
    token.string = token.string.replace(/\./, '');
  }
  return token;
}

CodeMirror.coffeescriptHint = function(editor, options) {
  return scriptHint(editor, coffeescriptKeywords, getCoffeeScriptToken, options);
};

var stringProps = ("charAt charCodeAt indexOf lastIndexOf substring substr slice trim trimLeft trimRight " +
                   "toUpperCase toLowerCase split concat match replace search").split(" ");
var arrayProps = ("length concat join splice push pop shift unshift slice reverse sort indexOf " +
                  "lastIndexOf every some filter forEach map reduce reduceRight ").split(" ");
var funcProps = "prototype apply call bind".split(" ");
var javascriptKeywords = ("break case catch continue debugger default delete do else false finally for function " +
                "if in instanceof new null return switch throw true try typeof var void while with").split(" ");
var coffeescriptKeywords = ("and break catch class continue delete do else extends false finally for " +
                "if in instanceof isnt new no not null of off on or return switch then throw true try typeof until void while with yes").split(" ");

function getCompletions(token, context, keywords, options) {
  var found = [], start = token.string;
  function maybeAdd(str) {
    if (str.indexOf(start) == 0 && !arrayContains(found, str)) found.push(str);
  }
  function gatherCompletions(obj) {
    if (typeof obj == "string") forEach(stringProps, maybeAdd);
    else if (obj instanceof Array) forEach(arrayProps, maybeAdd);
    else if (obj instanceof Function) forEach(funcProps, maybeAdd);
    for (var name in obj) maybeAdd(name);
  }

  if (context) {
    // If this is a property, see if it belongs to some object we can
    // find in the current environment.
    var obj = context.pop(), base;
    if (obj.className == "variable") {
      if (options && options.additionalContext)
        base = options.additionalContext[obj.string];
      base = base || window[obj.string];
    } else if (obj.className == "string") {
      base = "";
    } else if (obj.className == "atom") {
      base = 1;
    } else if (obj.className == "function") {
      if (window.jQuery != null && (obj.string == '$' || obj.string == 'jQuery') &&
          (typeof window.jQuery == 'function'))
        base = window.jQuery();
      else if (window._ != null && (obj.string == '_') && (typeof window._ == 'function'))
        base = window._();
    }
    while (base != null && context.length)
      base = base[context.pop().string];
    if (base != null) gatherCompletions(base);
  }
  else {
    // If not, just look in the window object and any local scope
    // (reading into JS mode internals to get at the local and global variables)
    for (var v = token.state.localVars; v; v = v.next) maybeAdd(v.name);
    for (var v = token.state.globalVars; v; v = v.next) maybeAdd(v.name);
    gatherCompletions(window);
    forEach(keywords, maybeAdd);
  }
  return found;
}

})();