Dynamic Event Manager

event.py

class EventGroup(object):
  def __init__(self):
    self._sub_events = {}
    self._listeners = set()
    self._batched = False
    self._batched_args = []

  def __getitem__(self, name):
    return self._sub_events.setdefault(name.lower(), EventGroup())

  def bind(self, callback):
    self._listeners.add(callback)

  def unbind(self, callback):
    if callback in self._listeners:
      self._listeners.remove(callback)

  def fire(self, *args, **kvargs):
    if self._batched:
      self._batched_args.append((args, kvargs))
    else:
      for callback in self._listeners:
        callback(*args, **kvargs)

  def begin_batch(self):
    self._batched = True
    self._batched_args = []

  def fire_batch(self, *args, **kvargs):
    if self._batched:
      self._batched = False
      self._batched_args = []
      self.fire(*args, **kvargs)

  @property
  def batched_args(self):
    return self._batched_args

  __getattr__ = __getitem__


class EventManager(object):

  def __init__(self):
    self._events = EventGroup()

  @property
  def events(self):
    return self._events

  def get(self, name, strict=False):
    evt_cnt = self.events
    for n in name.lower().split('.'):
      if strict:
        if n not in evt_cnt._sub_events:
          return None
      evt_cnt = evt_cnt[n]
    return evt_cnt

  def exists(self, name):
    exists, search_in = True, self._events
    for n in name.lower().split('.'):
      if n in search_in._sub_events.keys():
        search_in = search_in[n]
      else:
        exists = False
        break
    return exists


if __name__ == '__main__':
  mgr = EventManager()

  def callback():
    print 'callback'

  mgr.events.mouse.moved.bind(callback)

  mgr.events.mouse.moved.fire()
  mgr.get('mouse.moved').fire()

  print mgr.exists('mouse.moved')
  print mgr.exists('mouse.moved.yay')
  print mgr.exists('mouse.move.yay')