# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license

# Copyright (C) 2010, 2011 Nominum, Inc.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

import struct
import base64
import binascii

import dns.exception
import dns.rdata
import dns.rdatatype


class HIP(dns.rdata.Rdata):

    """HIP record"""

    # see: RFC 5205

    __slots__ = ['hit', 'algorithm', 'key', 'servers']

    def __init__(self, rdclass, rdtype, hit, algorithm, key, servers):
        super().__init__(rdclass, rdtype)
        object.__setattr__(self, 'hit', hit)
        object.__setattr__(self, 'algorithm', algorithm)
        object.__setattr__(self, 'key', key)
        object.__setattr__(self, 'servers', dns.rdata._constify(servers))

    def to_text(self, origin=None, relativize=True, **kw):
        hit = binascii.hexlify(self.hit).decode()
        key = base64.b64encode(self.key).replace(b'\n', b'').decode()
        text = ''
        servers = []
        for server in self.servers:
            servers.append(server.choose_relativity(origin, relativize))
        if len(servers) > 0:
            text += (' ' + ' '.join((x.to_unicode() for x in servers)))
        return '%u %s %s%s' % (self.algorithm, hit, key, text)

    @classmethod
    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True,
                  relativize_to=None):
        algorithm = tok.get_uint8()
        hit = binascii.unhexlify(tok.get_string().encode())
        if len(hit) > 255:
            raise dns.exception.SyntaxError("HIT too long")
        key = base64.b64decode(tok.get_string().encode())
        servers = []
        while 1:
            token = tok.get()
            if token.is_eol_or_eof():
                break
            server = tok.as_name(token, origin, relativize, relativize_to)
            servers.append(server)
        return cls(rdclass, rdtype, hit, algorithm, key, servers)

    def _to_wire(self, file, compress=None, origin=None, canonicalize=False):
        lh = len(self.hit)
        lk = len(self.key)
        file.write(struct.pack("!BBH", lh, self.algorithm, lk))
        file.write(self.hit)
        file.write(self.key)
        for server in self.servers:
            server.to_wire(file, None, origin, False)

    @classmethod
    def from_wire_parser(cls, rdclass, rdtype, parser, origin=None):
        (lh, algorithm, lk) = parser.get_struct('!BBH')
        hit = parser.get_bytes(lh)
        key = parser.get_bytes(lk)
        servers = []
        while parser.remaining() > 0:
            server = parser.get_name(origin)
            servers.append(server)
        return cls(rdclass, rdtype, hit, algorithm, key, servers)