# -*- coding: UTF-8 -*-

# Copyright (c) 2008 - 2013, Pascal Volk

# See COPYING for distribution information.

"""

    VirtualMailManager.emailaddress

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Virtual Mail Manager's EmailAddress class to handle e-mail addresses.

"""

import re

from VirtualMailManager.domain import check_domainname, get_gid

from VirtualMailManager.constants import \

     DOMAIN_NO_NAME, INVALID_ADDRESS, LOCALPART_INVALID, LOCALPART_TOO_LONG, \

     DOMAIN_INVALID

from VirtualMailManager.errors import DomainError, EmailAddressError as EAErr

RE_LOCALPART = re.compile(r"[^\w!#$%&'\*\+-\.\/=?^_`{\|}~]", re.ASCII)

_ = lambda msg: msg

class EmailAddress(object):

    """Simple class for validated e-mail addresses."""

    __slots__ = ('_localpart', '_domainname')

    def __init__(self, address, _validate=True):

        """Creates a new instance from the string/unicode ``address``."""

        assert isinstance(address, str)

        self._localpart = None

        self._domainname = None

        if _validate:

            self._chk_address(address)

    @property

    def localpart(self):

        """The local-part of the address *local-part@domain*"""

        return self._localpart

    @property

    def domainname(self):

        """The domain part of the address *local-part@domain*"""

        return self._domainname

    def __eq__(self, other):

        if isinstance(other, self.__class__):

            return self._localpart == other._localpart and \

                    self._domainname == other._domainname

        return NotImplemented

    def __ne__(self, other):

        if isinstance(other, self.__class__):

            return self._localpart != other._localpart or \

                    self._domainname != other._domainname

        return NotImplemented

    def __hash__(self):

        return hash((self._localpart.lower(), self._domainname.lower()))

    def __repr__(self):

        return "EmailAddress('%s@%s')" % (self._localpart, self._domainname)

    def __str__(self):

        return '%s@%s' % (self._localpart, self._domainname)

    def _chk_address(self, address):

        """Checks if the string ``address`` could be used for an e-mail

        address.  If so, it will assign the corresponding values to the

        attributes `_localpart` and `_domainname`."""

        parts = address.split('@')

        p_len = len(parts)

        if p_len < 2:

            raise EAErr(_("Missing the '@' sign in address: '%s'") % address,

                        INVALID_ADDRESS)

        elif p_len > 2:

            raise EAErr(_("Too many '@' signs in address: '%s'") % address,

                        INVALID_ADDRESS)

        if not parts[0]:

            raise EAErr(_("Missing local-part in address: '%s'") % address,

                        LOCALPART_INVALID)

        if not parts[1]:

            raise EAErr(_("Missing domain name in address: '%s'") % address,

                        DOMAIN_NO_NAME)

        self._localpart = check_localpart(parts[0])

        self._domainname = check_domainname(parts[1])

class DestinationEmailAddress(EmailAddress):

    """Provides additionally the domains group ID - when the domain is known

    in the database."""

    __slots__ = ('_gid', '_localhost')

    def __init__(self, address, dbh, _validate=False):

        """Creates a new DestinationEmailAddress instance

        Arguments:

        `address`: string/unicode

          a e-mail address like user@example.com

        `dbh`: psycopg2._psycopg.connection

          a database connection for the database access

        """

        super(DestinationEmailAddress, self).__init__(address, _validate)

        self._localhost = False

        if not _validate:

            try:

                self._chk_address(address)

            except DomainError as err:

                if err.code is DOMAIN_INVALID and \

                   address.split('@')[1] == 'localhost':

                    self._localhost = True

                    self._domainname = 'localhost'

                else:

                    raise

        self._gid = 0

        if not self._localhost:

            self._find_domain(dbh)

        else:

            self._localpart = self._localpart.lower()

    def _find_domain(self, dbh):

        """Checks if the domain is known"""

        self._gid = get_gid(dbh, self._domainname)

        if self._gid:

            self._localpart = self._localpart.lower()

    @property

    def at_localhost(self):

        """True when the address is something@localhost."""

        return self._localhost

    @property

    def gid(self):

        """The domains group ID. 0 if the domain is not known."""

        return self._gid

def check_localpart(localpart):

    """Returns the validated local-part `localpart`.

    Throws a `EmailAddressError` if the local-part is too long or contains

    invalid characters.

    """

    if len(localpart) > 64:

        raise EAErr(_("The local-part '%s' is too long.") % localpart,

                    LOCALPART_TOO_LONG)

    invalid_chars = set(RE_LOCALPART.findall(localpart))

    if invalid_chars:

        i_chars = ''.join(('"%s" ' % c for c in invalid_chars))

        raise EAErr(_("The local-part '%(l_part)s' contains invalid "

                      "characters: %(i_chars)s") % {'l_part': localpart,

                    'i_chars': i_chars}, LOCALPART_INVALID)

    return localpart

del _