"""
Ethernet (TCP/IP protocol stack)
"""
from construct import *
from construct.lib.py3compat import b
from binascii import hexlify, unhexlify


class MacAddressAdapter(Adapter):
    def _encode(self, obj, context):
        return unhexlify(obj.replace("-", ""))

    def _decode(self, obj, context):
        return "-".join(hexlify(b) for b in obj)


def MacAddress(name):
    return MacAddressAdapter(Bytes(name, 6))


ethernet_header = Struct("ethernet_header",
                         MacAddress("destination"),
                         MacAddress("source"),
                         Enum(UBInt16("type"),
                              IPv4=0x0800,
                              ARP=0x0806,
                              RARP=0x8035,
                              X25=0x0805,
                              IPX=0x8137,
                              IPv6=0x86DD,
                              _default_=Pass,
                              ),
                         )

if __name__ == "__main__":
    cap = unhexlify(b("0011508c283c0002e34260090800"))
    obj = ethernet_header.parse(cap)
    print(obj)
    print(repr(ethernet_header.build(obj)))
