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

# Copyright (c) 2008 - 2013, Pascal Volk

# See COPYING for distribution information.

"""

    VirtualMailManager.relocated

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

    Virtual Mail Manager's Relocated class to handle relocated users.

"""

from VirtualMailManager.domain import get_gid

from VirtualMailManager.emailaddress import EmailAddress, \

     DestinationEmailAddress

from VirtualMailManager.errors import RelocatedError as RErr

from VirtualMailManager.constants import DOMAIN_INVALID, NO_SUCH_DOMAIN, \

     NO_SUCH_RELOCATED, RELOCATED_ADDR_DEST_IDENTICAL, RELOCATED_EXISTS

_ = lambda msg: msg

class Relocated(object):

    """Class to handle e-mail addresses of relocated users."""

    __slots__ = ('_addr', '_dest', '_gid', '_dbh')

    def __init__(self, dbh, address):

        """Creates a new *Relocated* instance.  The ``address`` is the

        old e-mail address of the user.

        Use `setDestination()` to set/update the new address, where the

        user has moved to.

        """

        assert isinstance(address, EmailAddress)

        self._addr = address

        self._dbh = dbh

        self._gid = get_gid(self._dbh, self._addr.domainname)

        if not self._gid:

            raise RErr(_("The domain '%s' does not exist.") %

                       self._addr.domainname, NO_SUCH_DOMAIN)

        self._dest = None

        self._load()

    def __bool__(self):

        """Returns `True` if the Relocated is known, `False` if it's new."""

        return self._dest is not None

    def _load(self):

        """Loads the destination address from the database into the

        `_dest` attribute.

        """

        dbc = self._dbh.cursor()

        dbc.execute('SELECT destination FROM relocated WHERE gid = %s AND '

                    'address = %s', (self._gid, self._addr.localpart))

        destination = dbc.fetchone()

        dbc.close()

        if destination:

            destination = DestinationEmailAddress(destination[0], self._dbh)

            if destination.at_localhost:

                raise RErr(_("The destination address' domain name must not "

                             "be localhost."), DOMAIN_INVALID)

            self._dest = destination

    @property

    def address(self):

        """The Relocated's EmailAddress instance."""

        return self._addr

    def set_destination(self, destination):

        """Sets/updates the new address of the relocated user."""

        update = False

        assert isinstance(destination, DestinationEmailAddress)

        if destination.at_localhost:

            raise RErr(_("The destination address' domain name must not be "

                         "localhost."), DOMAIN_INVALID)

        if self._addr == destination:

            raise RErr(_('Address and destination are identical.'),

                       RELOCATED_ADDR_DEST_IDENTICAL)

        if self._dest:

            if self._dest == destination:

                raise RErr(_("The relocated user '%s' already exists.") %

                           self._addr, RELOCATED_EXISTS)

            else:

                self._dest = destination

                update = True

        else:

            self._dest = destination

        dbc = self._dbh.cursor()

        if not update:

            dbc.execute('INSERT INTO relocated (gid, address, destination) '

                        'VALUES (%s, %s, %s)',

                        (self._gid, self._addr.localpart, str(self._dest)))

        else:

            dbc.execute('UPDATE relocated SET destination = %s WHERE gid = %s '

                        'AND address = %s',

                        (str(self._dest), self._gid, self._addr.localpart))

        self._dbh.commit()

        dbc.close()

    def get_info(self):

        """Returns the address to which mails should be sent."""

        if not self._dest:

            raise RErr(_("The relocated user '%s' does not exist.") %

                       self._addr, NO_SUCH_RELOCATED)

        return self._dest

    def delete(self):

        """Deletes the relocated entry from the database."""

        if not self._dest:

            raise RErr(_("The relocated user '%s' does not exist.") %

                       self._addr, NO_SUCH_RELOCATED)

        dbc = self._dbh.cursor()

        dbc.execute('DELETE FROM relocated WHERE gid = %s AND address = %s',

                    (self._gid, self._addr.localpart))

        if dbc.rowcount > 0:

            self._dbh.commit()

        dbc.close()

        self._dest = None

del _