1#!/usr/bin/env python3 2# coding=utf-8 3 4# 5# Copyright (c) 2020-2023 Huawei Device Co., Ltd. 6# Licensed under the Apache License, Version 2.0 (the "License"); 7# you may not use this file except in compliance with the License. 8# You may obtain a copy of the License at 9# 10# http://www.apache.org/licenses/LICENSE-2.0 11# 12# Unless required by applicable law or agreed to in writing, software 13# distributed under the License is distributed on an "AS IS" BASIS, 14# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15# See the License for the specific language governing permissions and 16# limitations under the License. 17# 18 19from _core.context.single import SingleType 20 21__all__ = ["CommandQueue"] 22 23 24class CommandQueue(metaclass=SingleType): 25 __instance = None 26 _queue = [] 27 28 @classmethod 29 def append(cls, command): 30 cls._queue.append(command) 31 32 @classmethod 33 def pop(cls, index=-1): 34 return cls._queue.pop(index) 35 36 @classmethod 37 def get_last(cls): 38 return cls._queue[-1] 39 40 @classmethod 41 def get(cls, index: int): 42 return cls._queue[index] 43 44 @classmethod 45 def update(cls, index, command): 46 cls._queue[index] = command 47 48 @classmethod 49 def list_history(cls): 50 for command_info in cls._queue[:-1]: 51 yield command_info 52 53 @classmethod 54 def size(cls): 55 return len(cls._queue) 56 57 @classmethod 58 def is_empty(cls): 59 return cls.size() == 0 60