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

# Copyright (c) 2008 - 2013, Pascal Volk

# See COPYING for distribution information.

"""

    VirtualMailManager.aliasdomain

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

    Virtual Mail Manager's AliasDomain class to manage alias domains.

"""

from VirtualMailManager.domain import Domain, check_domainname

from VirtualMailManager.constants import \

     ALIASDOMAIN_EXISTS, ALIASDOMAIN_ISDOMAIN, ALIASDOMAIN_NO_DOMDEST, \

     NO_SUCH_ALIASDOMAIN, NO_SUCH_DOMAIN

from VirtualMailManager.errors import AliasDomainError as ADErr

_ = lambda msg: msg

class AliasDomain(object):

    """Class to manage e-mail alias domains."""

    __slots__ = ('_gid', '_name', '_domain', '_dbh')

    def __init__(self, dbh, domainname):

        """Creates a new AliasDomain instance.

        Arguments:

        `dbh` : psycopg2._psycopg.connection

          a database connection for the database access

        `domainname` : basestring

          the name of the AliasDomain"""

        self._dbh = dbh

        self._name = check_domainname(domainname)

        self._gid = 0

        self._domain = None

        self._load()

    def _load(self):

        """Loads the AliasDomain's GID from the database and checks if the

        domain name is marked as primary."""

        dbc = self._dbh.cursor()

        dbc.execute('SELECT gid, is_primary FROM domain_name WHERE '

                    'domainname = %s', (self._name,))

        result = dbc.fetchone()

        dbc.close()

        if result:

            if result[1]:

                raise ADErr(_("The domain '%s' is a primary domain.") %

                            self._name, ALIASDOMAIN_ISDOMAIN)

            self._gid = result[0]

    def set_destination(self, dest_domain):

        """Set the destination of a new AliasDomain or updates the

        destination of an existing AliasDomain.

        Argument:

        `dest_domain` : VirtualMailManager.Domain.Domain

          the AliasDomain's destination domain

        """

        assert isinstance(dest_domain, Domain)

        self._domain = dest_domain

    def save(self):

        """Stores information about the new AliasDomain in the database."""

        if self._gid > 0:

            raise ADErr(_("The alias domain '%s' already exists.") %

                        self._name, ALIASDOMAIN_EXISTS)

        if not self._domain:

            raise ADErr(_('No destination domain set for the alias domain.'),

                        ALIASDOMAIN_NO_DOMDEST)

        if self._domain.gid < 1:

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

                        self._domain.name, NO_SUCH_DOMAIN)

        dbc = self._dbh.cursor()

        dbc.execute('INSERT INTO domain_name (domainname, gid, is_primary) '

                    'VALUES (%s, %s, FALSE)', (self._name, self._domain.gid))

        self._dbh.commit()

        dbc.close()

        self._gid = self._domain.gid

    def info(self):

        """Returns a dict (keys: "alias" and "domain") with the names of the

        AliasDomain and its primary domain."""

        if self._gid < 1:

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

                        self._name, NO_SUCH_ALIASDOMAIN)

        dbc = self._dbh.cursor()

        dbc.execute('SELECT domainname FROM domain_name WHERE gid = %s AND '

                    'is_primary', (self._gid,))

        domain = dbc.fetchone()

        dbc.close()

        if domain:

            return {'alias': self._name, 'domain': domain[0]}

        else:  # an almost unlikely case, isn't it?

            raise ADErr(_('There is no primary domain for the alias domain '

                          "'%s'.") % self._name, NO_SUCH_DOMAIN)

    def switch(self):

        """Switch the destination of the AliasDomain to the new destination,

        set with the method `set_destination()`.

        """

        if not self._domain:

            raise ADErr(_('No destination domain set for the alias domain.'),

                        ALIASDOMAIN_NO_DOMDEST)

        if self._domain.gid < 1:

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

                        self._domain.name, NO_SUCH_DOMAIN)

        if self._gid < 1:

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

                        self._name, NO_SUCH_ALIASDOMAIN)

        if self._gid == self._domain.gid:

            raise ADErr(_("The alias domain '%(alias)s' is already assigned "

                          "to the domain '%(domain)s'.") %

                        {'alias': self._name, 'domain': self._domain.name},

                        ALIASDOMAIN_EXISTS)

        dbc = self._dbh.cursor()

        dbc.execute('UPDATE domain_name SET gid = %s WHERE gid = %s AND '

                    'domainname = %s AND NOT is_primary', (self._domain.gid,

                    self._gid, self._name))

        self._dbh.commit()

        dbc.close()

        self._gid = self._domain.gid

    def delete(self):

        """Delete the AliasDomain's record form the database.

        Raises an AliasDomainError if the AliasDomain doesn't exist.

        """

        if self._gid < 1:

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

                        self._name, NO_SUCH_ALIASDOMAIN)

        dbc = self._dbh.cursor()

        dbc.execute('DELETE FROM domain_name WHERE domainname = %s AND NOT '

                    'is_primary', (self._name,))

        if dbc.rowcount > 0:

            self._dbh.commit()

            self._gid = 0

        dbc.close()

del _