# -*- coding: utf-8 -*-

# 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 3 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, see <http://www.gnu.org/licenses/>.

"""

kallithea.lib.celerylib

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

celery libs for Kallithea

This file was forked by the Kallithea project in July 2014.

Original author and date, and relevant copyright and licensing information is below:

:created_on: Nov 27, 2010

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import os

import logging

from tg import config

from hashlib import md5

from decorator import decorator

from kallithea import CELERY_ON, CELERY_EAGER

from kallithea.lib.utils2 import safe_str

from kallithea.lib.pidlock import DaemonLock, LockHeld

from kallithea.model.base import init_model

from kallithea.model import meta

from sqlalchemy import engine_from_config

log = logging.getLogger(__name__)

class FakeTask(object):

    """Fake a sync result to make it look like a finished task"""

    def __init__(self, result):

        self.result = result

    def failed(self):

        return False

    traceback = None # if failed

    task_id = None

def task(f_org):

    """Wrapper of celery.task.task, running async if CELERY_ON

    """

    if CELERY_ON:

        def f_async(*args, **kwargs):

            log.info('executing %s task', f_org.__name__)

            try:

                f_org(*args, **kwargs)

            finally:

                log.info('executed %s task', f_org.__name__)

        f_async.__name__ = f_org.__name__

        from kallithea.lib import celerypylons

        runner = celerypylons.task(ignore_result=True)(f_async)

        def f_wrapped(*args, **kwargs):

            t = runner.apply_async(args=args, kwargs=kwargs)

            log.info('executing task %s in async mode - id %s', f_org, t.task_id)

            return t

    else:

        def f_wrapped(*args, **kwargs):

            log.info('executing task %s in sync', f_org.__name__)

            try:

                result = f_org(*args, **kwargs)

            except Exception as e:

                raise # TODO: return this in FakeTask as with async tasks?

            return FakeTask(result)

    return f_wrapped

def __get_lockkey(func, *fargs, **fkwargs):

    params = list(fargs)

    params.extend(['%s-%s' % ar for ar in fkwargs.items()])

    func_name = str(func.__name__) if hasattr(func, '__name__') else str(func)

    lockkey = 'task_%s.lock' % \

        md5(func_name + '-' + '-'.join(map(safe_str, params))).hexdigest()

    return lockkey

def locked_task(func):

    def __wrapper(func, *fargs, **fkwargs):

        lockkey = __get_lockkey(func, *fargs, **fkwargs)

        lockkey_path = config['app_conf']['cache_dir']

        log.info('running task with lockkey %s', lockkey)

        try:

            l = DaemonLock(file_=os.path.join(lockkey_path, lockkey))

            ret = func(*fargs, **fkwargs)

            l.release()

            return ret

        except LockHeld:

            log.info('LockHeld')

            return 'Task with key %s already running' % lockkey

    return decorator(__wrapper, func)

def get_session():

    if CELERY_ON:

        engine = engine_from_config(config, 'sqlalchemy.')

        init_model(engine)

    sa = meta.Session()

    return sa

def dbsession(func):

    def __wrapper(func, *fargs, **fkwargs):

        try:

            ret = func(*fargs, **fkwargs)

            return ret

        finally:

            if CELERY_ON and not CELERY_EAGER:

                meta.Session.remove()

    return decorator(__wrapper, func)