设计模式之命令模式

from abc import ABCMeta, abstractmethod


# 命令模式四个角色：命令、接收者、调度者、用户
# 对命令的发送者和接收者进行解耦，高内聚
# 其中的调度者有点像Scrapy框架中的Scheduler,对请求和响应进行调度
class Command(metaclass=ABCMeta):
    """命令的抽象类"""
    @abstractmethod
    def execute(self):
        pass


class CommandImpl(Command):
    """命令的具体实现类"""
    def __init__(self, receiver):
        self.__receiver = receiver

    def execute(self):
        self.__receiver.doSomethig()


class Receiver:
    """命令的接收者"""
    def doSomethig(self):
        print("do Something...")


class Invoker:
    """调度者"""
    def __init__(self):
        self.__command = None

    def setCommand(self, command):
        self.__command = command

    def action(self):
        if self.__command is not None:
            self.command.execute()


# 实战应用
class GameRole:
    """游戏的角色"""
    STEP = 5

    def __init__(self, name):
        self.__name = name
        self.__x = 0
        self.__y = y
        self.__z = z

    def leftMove(self):
        self.__x -= self.STEP

    def rightMove(self):
        self.__x += self.STEP

    def upMove(self):
        self.__y += self.STEP

    def downMove(self):
        self.__y -= self.STEP

    def jumpMove(self):
        self.__z += self.STEP

    def squatMove(self):
        self.__z -= self.STEP

    def attack(self):
        print("%s发动了攻击..." % self.__name)

    def showPosition(self):
        print("%s 的位置：（x:%s, y:%s, z:%s）" % (self.__name, self.__x, self.__y, self.__z))


class GameCommamd(metaclass=ABCMeta):
    """游戏角色的命令类"""
    def __init__(self, role):
        self.__role = role

    def setRole(self, role):
        self.__role = role

    @abstractmethod
    def execute(self):
        pass


class Left(GameCommamd):
    """左移"""
    def execute(self):
        self.__role.leftMove()
        self.__role.showPosition()


class Right(GameCommamd):
    """右移"""
    def execute(self):
        self.__role.rightMove()
        self.__role.showPosition()

class Up(GameCommamd):
    """上移"""
    def execute(self):
        self.__role.upMove()
        self.__role.showPosition()

class Down(GameCommamd):
    """下移"""
    def execute(self):
        self.__role.downMove()
        self.__role.showPosition()


class Jump(GameCommamd):
    """弹跳"""
    def execute(self):
        self.__role.jumpMove()
        self.__role.showPosition()


class Squat(GameCommamd):
    """下蹲"""
    def execute(self):
        self.__role.squatMove()
        self.__role.showPosition()


class Attack(GameCommamd):
    """攻击"""
    def execute(self):
        self.__role.attack()
        self.__role.showPosition()


class MacroCommand(GameCommamd):
    """"组合"""
    def __init__(self, role=None):
        super().__init__(role)
        self.__commands = []

    def addCommand(self, command):
        self.__commands.append(command)

    def execute(self):
        for command in self.__commands:
            command.execute()

class GameInvoker:
    """命令调度者"""
    def __init__(self):
        self.__command = None

    def setCommand(self, command):
        self.__command = command

    def action(self):
        if self.__command is not None:
            self.__command.execute()