from dataclasses import dataclass, field from typing import Tuple @dataclass(init=False) class Address: address: bytes = field(default=bytes([0, 0, 0, 0, 0, 0])) def __init__(self, address=None): if not address: self.address = bytes([0, 0, 0, 0, 0, 0]) elif isinstance(address, Address): self.address = address.address elif isinstance(address, str): self.address = bytes([int(b, 16) for b in address.split(':')]) elif isinstance(address, (bytes, list)) and len(address) == 6: self.address = bytes(address) elif isinstance(address, bytes): address = address.decode('utf-8') self.address = bytes([int(b, 16) for b in address.split(':')]) else: raise Exception(f'unsupported address type: {address}') def parse(span: bytes) -> Tuple['Address', bytes]: assert len(span) >= 6 return (Address(bytes(reversed(span[:6]))), span[6:]) def parse_all(span: bytes) -> 'Address': assert len(span) == 6 return Address(bytes(reversed(span))) def serialize(self) -> bytes: return bytes(reversed(self.address)) def is_resolvable(self) -> bool: return (self.address[0] & 0xc0) == 0x40 def is_non_resolvable(self) -> bool: return (self.address[0] & 0xc0) == 0x00 def is_static_identity(self) -> bool: return (self.address[0] & 0xc0) == 0xc0 def __repr__(self) -> str: return ':'.join([f'{b:02x}' for b in self.address]) @property def size(self) -> int: return 6 @dataclass class ClassOfDevice: def parse(span: bytes) -> Tuple['Address', bytes]: assert False def parse_all(span: bytes) -> 'Address': assert False def serialize(self) -> bytes: assert False @property def size(self) -> int: assert False