#!/usr/bin/env python
# -*- encoding: utf-8 -*-
"""
filename: descriptor_2_2.py
description: python descriptor
License: GPL V2
Author: 天使de眼睛

除特别声明，所有代码均是 python3.6 在 iOS 环境下编写测试。

运行代码需要 pytest
    pip install pytest
"""
from ipaddress import ip_address

import pytest


class Descriptor:
    def __init__(self, name):
        self.name = name

    def __get__(self, instance, cls):
        return instance.__dict__[self.name]

    def __set__(self, instance, value):
        instance.__dict__[self.name] = value


class TypeCheck(Descriptor):
    obj_type = object

    def __set__(self, instance, value):
        if not isinstance(value, self.obj_type):
            raise TypeError(f"Expected {self.obj_type}")
        super().__set__(instance, value)


class String(TypeCheck):
    obj_type = str


class Upper(Descriptor):
    def __set__(self, instance, value):
        super().__set__(instance, value.upper())


class UpperString(String, Upper):
    pass


class IPAddress(Descriptor):
    def __set__(self, instance, value):
        super().__set__(instance, ip_address(value))

class IP(String, IPAddress):
    pass

class Integer(TypeCheck):
    obj_type = int

class Greater(Descriptor):
    def __init__(self, *args, greater=None, **kwargs):
        self.greater = greater
        super().__init__(*args, **kwargs)

    def __set__(self, instance, value):
        if value < (self.greater or value):
            raise ValueError(f'{self.name} must >= {self.greater}')
        super().__set__(instance, value)

class Less(Descriptor):
    def __init__(self, *args, less=None, **kwargs):
        self.less = less
        super().__init__(*args, **kwargs)

    def __set__(self, instance, value):
        if value > (self.less or value):
            raise ValueError(f'{self.name} must <= {self.less}')
        super().__set__(instance, value)

class Port(Integer, Greater, Less):
    pass

class Server:
    name = UpperString("name")
    ip = IP("ip")
    rack = Integer('rack')

    def __init__(self, name, ip, rack):
        self.name = name
        self.ip = ip
        self.rack = rack


class Protocol:
    protocol = UpperString("protocol")
    source = IP("source")
    destination = IP("destination")
    port = Port("port", greater=1, less=65535)

    def __init__(self, protocol, source, destinatioin, port):
        self.protocol = protocol
        self.source = source
        self.destination = destinatioin
        self.port = port


class TestClasses:
    def test_Server(self):
        server = Server('myserver1', '192.168.1.1', 5)
        assert server.name == 'MYSERVER1'
        assert server.ip == ip_address('192.168.1.1')
        with pytest.raises(TypeError) as error:
            server.name = 123
        assert str(error.value) == "Expected <class 'str'>"
        with pytest.raises(TypeError) as error:
            server.ip = 123
        assert str(error.value) == "Expected <class 'str'>"
        assert server.rack == 5
        with pytest.raises(TypeError) as error:
            server.rack = 'up'
        assert str(error.value) == "Expected <class 'int'>"

    def test_Protocol(self):
        logger = Protocol('tcp', '192.168.1.1', '10.1.1.1', 8080)
        assert logger.protocol == 'TCP'
        assert logger.source == ip_address('192.168.1.1')
        assert logger.destination == ip_address('10.1.1.1')
        with pytest.raises(TypeError) as error:
            logger.protocol = ['tcp']
        assert str(error.value) == "Expected <class 'str'>"
        with pytest.raises(TypeError) as error:
            logger.source = 55
        assert str(error.value) == "Expected <class 'str'>"
        assert logger.port == 8080
        with pytest.raises(ValueError) as error:
            logger.port = 0
        assert str(error.value) == "port must >= 1"
        with pytest.raises(ValueError) as error:
            logger.port = 65536
        assert str(error.value) == "port must <= 65535"



if __name__ == '__main__':
    import sys

    pytest.main(sys.argv + ['-v'])