+class Task:
+
+ def __init__(self, name, args=(), kwargs={}):
+ self.name = name
+ self.args = args
+ self.kwargs = kwargs
+ self.todo = 1
+
+
+class Thing:
+
+ def __init__(self, type_, position):
+ self.type = type_
+ self.position = position
+ self.task = Task('wait')
+
+ def task_wait(self):
+ pass
+
+ def task_move(self, direction):
+ if direction == 'UP':
+ self.position[0] -= 1
+ elif direction == 'DOWN':
+ self.position[0] += 1
+ elif direction == 'RIGHT':
+ self.position[1] += 1
+ elif direction == 'LEFT':
+ self.position[1] -= 1
+
+ def decide_task(self):
+ if self.position[1] > 1:
+ self.set_task('move', 'LEFT')
+ elif self.position[1] < 3:
+ self.set_task('move', 'RIGHT')
+ else:
+ self.set_task('wait')
+
+ def set_task(self, task, *args, **kwargs):
+ self.task = Task(task, args, kwargs)
+
+ def proceed(self, is_AI=True):
+ """Further the thing in its tasks.
+
+ Decrements .task.todo; if it thus falls to <= 0, enacts method whose
+ name is 'task_' + self.task.name and sets .task = None. If is_AI, calls
+ .decide_task to decide a self.task.
+ """
+ self.task.todo -= 1
+ if self.task.todo <= 0:
+ task = getattr(self, 'task_' + self.task.name)
+ task(*self.task.args, **self.task.kwargs)
+ self.task = None
+ if is_AI and self.task is None:
+ self.decide_task()
+
+