window.Keycodes = {
  BACKSPACE:      8,
  TAB:            9,
  ENTER:         13,
  RETURN:        13,
  SHIFT:         16,
  CTRL:          17,
  ALT:           18,
  PAUSE:         19,
  BREAK:         19,
  CAPSLOCK:      20,
  ESCAPE:        27,
  ESC:           27,
  SPACEBAR:      32,
  SPACE:         32,
  PAGEUP:        33,
  PAGEDOWN:      34,
  END:           35,
  HOME:          36,
  LEFT:          37,
  UP:            38,
  RIGHT:         39,
  DOWN:          40,
  INSERT:        45,
  DEL:           46,
  DELETE:        46,
  0:             48,
  1:             49,
  2:             50,
  3:             51,
  4:             52,
  5:             53,
  6:             54,
  7:             55,
  8:             56,
  9:             57,
  A:             65,
  B:             66,
  C:             67,
  D:             68,
  E:             69,
  F:             70,
  G:             71,
  H:             72,
  I:             73,
  J:             74,
  K:             75,
  L:             76,
  M:             77,
  N:             78,
  O:             79,
  P:             80,
  Q:             81,
  R:             82,
  S:             83,
  T:             84,
  U:             85,
  V:             86,
  W:             87,
  X:             88,
  Y:             89,
  Z:             90,
  LEFTWINDOW:    91,
  RIGHTWINDOW:   92,
  SELECT:        93,
  NUMPAD0:       96,
  NUMPAD1:       97,
  NUMPAD2:       98,
  NUMPAD3:       99,
  NUMPAD4:      100,
  NUMPAD5:      101,
  NUMPAD6:      102,
  NUMPAD7:      103,
  NUMPAD8:      104,
  NUMPAD9:      105,
  MULTIPLY:     106,
  ADD:          107,
  SUBTRACT:     109,
  DECIMALPOINT: 110,
  DIVIDE:       111,
  F1:           112,
  F2:           113,
  F3:           114,
  F4:           115,
  F5:           116,
  F6:           117,
  F7:           118,
  F8:           119,
  F9:           120,
  F10:          121,
  F11:          122,
  F12:          123,
  NUMLOCK:      144,
  SCROLLLOCK:   145,
  SEMICOLON:    186,
  EQUALSIGN:    187,
  COMMA:        188,
  DASH:         189,
  PERIOD:       190,
  FORWARDSLASH: 191,
  ACCENTGRAVE:  192,
  OPENBRACKET:  219,
  BACKSLASH:    220,
  CLOSEBRACKET: 221,
  SINGLEQUOTE:  222,
  isInsertion:  function(keyCode) {
    if(keyCode <= 46 && keyCode !== this.RETURN && keyCode !== this.SPACEBAR) {
      return false;
    } else if(keyCode > 90 && keyCode < 96) {
      return false;
    } else if(keyCode >= 112 && keyCode <= 145) {
      return false;
    } else {
      return true;
    }
  }
};