from pyroute2.nftables.parser.parser import nfta_nla_parser, conv_map_tuple
from pyroute2.nftables.parser.expr import (
    get_expression_from_netlink,
    get_expression_from_dict)


NAME_2_NFPROTO = {
    "unspec": 0,
    "inet": 1,
    "ipv4": 2,
    "arp": 3,
    "netdev": 5,
    "bridge": 7,
    "ipv6": 10,
    "decnet": 12,
}
NFPROTO_2_NAME = {v: k for k, v in NAME_2_NFPROTO.items()}


class NFTRule(nfta_nla_parser):

    conv_maps = (
        conv_map_tuple('family', 'nfgen_family', 'family', 'nfproto'),
        conv_map_tuple('table', 'NFTA_RULE_TABLE', 'table', 'raw'),
        conv_map_tuple('chain', 'NFTA_RULE_CHAIN', 'chain', 'raw'),
        conv_map_tuple('handle', 'NFTA_RULE_HANDLE', 'handle', 'raw'),
        conv_map_tuple('expressions', 'NFTA_RULE_EXPRESSIONS', 'expr',
                       'expressions_list'),
        conv_map_tuple('compat', 'NFTA_RULE_COMPAT', 'compat', 'raw'),
        conv_map_tuple('position', 'NFTA_RULE_POSITION', 'position', 'raw'),
        conv_map_tuple('userdata', 'NFTA_RULE_USERDATA', 'userdata',
                       'user_data'),
        conv_map_tuple('rule_id', 'NFTA_RULE_ID', 'rule_id', 'raw'),
        conv_map_tuple('position_id', 'NFTA_RULE_POSITION_ID', 'position_id',
                       'raw'),
    )

    @classmethod
    def from_netlink(cls, ndmsg):
        obj = super(NFTRule, cls).from_netlink(ndmsg)
        obj.family = cls.cparser_nfproto.from_netlink(
            ndmsg['nfgen_family'])
        return obj

    class cparser_user_data(object):
        def __init__(self, udata_type, value):
            self.type = udata_type
            self.value = value

        @classmethod
        def from_netlink(cls, userdata):
            userdata = [int(d, 16) for d in userdata.split(':')]
            udata_type = userdata[0]
            udata_len = userdata[1]
            udata_value = ''.join([chr(d) for d in userdata[2:udata_len + 2]])
            if udata_type == 0:
                # 0 == COMMENT
                return cls('comment', udata_value)
            raise NotImplementedError("userdata type: {0}".format(udata_type))

        @staticmethod
        def to_netlink(udata):
            if udata.type == 'comment':
                userdata = '00:'
            else:
                raise NotImplementedError(
                    "userdata type: {0}".format(udata.type))
            userdata += "%0.2X:" % len(udata.value)
            userdata += ':'.join(["%0.2X" % ord(d) for d in udata.value])
            return userdata

        @staticmethod
        def to_dict(udata):
            # Currently nft command to not export userdata to dict
            return None
            if udata.type == "comment":
                return {"type": "comment", "value": udata.value}
            raise NotImplementedError("userdata type: {0}".format(udata.type))

        @classmethod
        def from_dict(cls, d):
            # See to_dict() method
            return None

    class cparser_expressions_list(object):

        @staticmethod
        def from_netlink(expressions):
            return [get_expression_from_netlink(e) for e in expressions]

        @staticmethod
        def to_netlink(expressions):
            return [e.to_netlink() for e in expressions]

        @staticmethod
        def from_dict(expressions):
            return [get_expression_from_dict(e) for e in expressions]

        @staticmethod
        def to_dict(expressions):
            return [e.to_dict() for e in expressions]

    class cparser_nfproto(object):

        @staticmethod
        def from_netlink(val):
            return NFPROTO_2_NAME[val]

        @staticmethod
        def to_netlink(val):
            return NAME_2_NFPROTO[val]

        @staticmethod
        def from_dict(val):
            return val

        @staticmethod
        def to_dict(val):
            return val
