# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

#

# This file is part of CubicWeb.

#

# CubicWeb is free software: you can redistribute it and/or modify it under the

# terms of the GNU Lesser General Public License as published by the Free

# Software Foundation, either version 2.1 of the License, or (at your option)

# any later version.

#

# CubicWeb 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 Lesser General Public License for more

# details.

#

# You should have received a copy of the GNU Lesser General Public License along

# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""core hooks registering some maintainance tasks as server startup time"""

__docformat__ = "restructuredtext en"

from datetime import timedelta, datetime

from cubicweb.server import hook

class TransactionsCleanupStartupHook(hook.Hook):

    """start task to cleanup transaction data"""

    __regid__ = 'cw.looping-tasks.transactions-cleanup'

    events = ('server_startup',)

    def __call__(self):

        # XXX use named args and inner functions to avoid referencing globals

        # which may cause reloading pb

        lifetime = timedelta(days=self.repo.config['keep-transaction-lifetime'])

        def cleanup_old_transactions(repo=self.repo, lifetime=lifetime):

            mindate = datetime.now() - lifetime

            session = repo.internal_session()

            try:

                session.system_sql(

                    'DELETE FROM transactions WHERE tx_time < %(time)s',

                    {'time': mindate})

                session.commit()

            finally:

                session.close()

        if self.repo.config['undo-enabled']:

            self.repo.looping_task(60*60*24, cleanup_old_transactions,

                                   self.repo)

class UpdateFeedsStartupHook(hook.Hook):

    """start task to update datafeed based sources"""

    __regid__ = 'cw.looping-tasks.update-feeds'

    events = ('server_startup',)

    def __call__(self):

        def update_feeds(repo):

            # take a list to avoid iterating on a dictionary whose size may

            # change

            for uri, source in list(repo.sources_by_uri.iteritems()):

                if (uri == 'system'

                    or not repo.config.source_enabled(source)

                    or not source.config['synchronize']):

                    continue

                session = repo.internal_session(safe=True)

                try:

                    source.pull_data(session)

                except Exception as exc:

                    session.exception('while trying to update feed %s', source)

                finally:

                    session.close()

        self.repo.looping_task(60, update_feeds, self.repo)

class DataImportsCleanupStartupHook(hook.Hook):

    """start task to cleanup old data imports (ie datafeed import logs)"""

    __regid__ = 'cw.looping-tasks.dataimports-cleanup'

    events = ('server_startup',)

    def __call__(self):

        def expire_dataimports(repo=self.repo):

            for uri, source in repo.sources_by_uri.iteritems():

                if (uri == 'system'

                    or not repo.config.source_enabled(source)):

                    continue

                session = repo.internal_session()

                try:

                    mindate = datetime.now() - timedelta(seconds=source.config['logs-lifetime'])

                    session.execute('DELETE CWDataImport X WHERE X start_timestamp < %(time)s',

                                    {'time': mindate})

                    session.commit()

                finally:

                    session.close()

        self.repo.looping_task(60*60*24, expire_dataimports, self.repo)