# Copyright (C) 2007 by the Free Software Foundation, Inc.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
# USA.

"""SQLAlchemy/Elixir based provider of IListManager."""

import weakref

from elixir import *
from zope.interface import implements

from Mailman import Errors
from Mailman.Utils import split_listname, fqdn_listname
from Mailman.configuration import config
from Mailman.database.model import MailingList
from Mailman.interfaces import IListManager



class ListManager(object):
    implements(IListManager)

    def __init__(self):
        self._objectmap = weakref.WeakKeyDictionary()

    def create(self, fqdn_listname):
        listname, hostname = split_listname(fqdn_listname)
        mlist = MailingList.get_by(list_name=listname,
                                   host_name=hostname)
        if mlist:
            raise Errors.MMListAlreadyExistsError(fqdn_listname)
        mlist = MailingList(fqdn_listname)
        # Wrap the database model object in an application MailList object and
        # return the latter.  Keep track of the wrapper so we can clean it up
        # when we're done with it.
        from Mailman.MailList import MailList
        wrapper = MailList(mlist)
        self._objectmap[mlist] = wrapper
        return wrapper

    def delete(self, mlist):
        # Delete the wrapped backing data.  XXX It's kind of icky to reach
        # into the MailList object this way.
        mlist._data.delete()
        mlist._data = None

    def get(self, fqdn_listname):
        listname, hostname = split_listname(fqdn_listname)
        mlist = MailingList.get_by(list_name=listname,
                                   host_name=hostname)
        if not mlist:
            raise Errors.MMUnknownListError(fqdn_listname)
        from Mailman.MailList import MailList
        wrapper = self._objectmap.setdefault(mlist, MailList(mlist))
        return wrapper

    @property
    def mailing_lists(self):
        # Don't forget, the MailingList objects that this class manages must
        # be wrapped in a MailList object as expected by this interface.
        for fqdn_listname in self.names:
            yield self.get(fqdn_listname)

    @property
    def names(self):
        for mlist in MailingList.select():
            yield fqdn_listname(mlist.list_name, mlist.host_name)