evens_and_odds_improved.py

import socket
import struct
import time

JOIN = 0
PLAY = 1


class Player:
    def __init__(self, address, choice):
        self.address = address
        self.choice = choice
        self.move = None

    def __repr__(self):
        return str(self.address)


class EvensAndOddsServer:

    def __init__(self, address, port):
        self.address = address
        self.port = port
        self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        self.socket.settimeout(30.0)
        self.socket.bind((self.address, self.port))
        self.players = [None, None]

    @property
    def in_game(self):
        return self.players[0] and self.players[1]

    def get_winner(self, value):
        if value % 2 == self.players[0].choice % 2:
            print('player {} WINS'.format(self.players[0]))
        if value % 2 == self.players[1].choice % 2:
            print('player {} WINS'.format(self.players[1]))

    def tick(self):
        try:
            self.packet, self.sender = self.socket.recvfrom(64)
        except socket.timeout:
            if self.players[0] is not None:
                print('timeout')
            self.players = [None, None]
            return

        if len(self.packet) != 2:
            return

        command, value = struct.unpack('=BB', self.packet)
        if command == JOIN:
            self.join(value)
        elif command == PLAY:
            self.play(value)

        total = 0

        if self.in_game:
            for player in self.players:
                if player.move is None:
                    return
                total += player.move
        else:
            return

        # if i am here, check victory
        self.get_winner(total)

        self.players = [None, None]

    def join(self, value):
        if self.in_game:
            return
        player = Player(self.sender, value)
        if self.players[0] is None:
            self.players[0] = player
        elif self.players[1] is None:
            player.choice = self.players[0].choice + 1
            self.players[1] = player
        else:
            return
        print('player {} joined as {}'.format(player, player.choice % 2))

    def get_player(self, address):
        if self.players[0].address == address:
            return self.players[0]
        if self.players[1].address == address:
            return self.players[1]
        return None

    def play(self, value):
        if not self.in_game:
            return
        player = self.get_player(self.sender)
        if not player:
            return
        if player.move is not None:
            return
        print('player {} moved'.format(player))
        player.move = value

    def run(self):
        print('server is running')
        while True:
            self.tick()


game = EvensAndOddsServer('192.168.10.1', 9999)
game.run()