[Яростный Меч]

Вот набросок очереди команд:

function CommandQueue(limit) {
  this._limit = limit || 10;
  this._arr = [];
  this._pointer = -1;
}

CommandQueue.prototype.undoCount = function() {
  return this._pointer + 1;
};
CommandQueue.prototype.redoCount = function() {
  return this._arr.length - this._pointer - 1;
};

CommandQueue.prototype.undo = function() {
  if (!this.undoCount()) {
    return false;
  }
  this._arr[this._pointer].undo();
  this._pointer--;
  return true;
};

CommandQueue.prototype.redo = function() {
  if (!this.redoCount()) {
    return false;
  }
  this._pointer++;
  this._arr[this._pointer].redo();
  return true;
};

CommandQueue.prototype.action = function(command) {
  this._arr.splice(this._pointer + 1, this.redoCount(), command);
  this.redo();
  if (this._arr.length > this._limit) {
    this._arr.shift();
    this._pointer--;
  }
};

использование:

var q = new CommandQueue(10);
q.action({
  undo: function() {...},
  redo: function() {...}
});