"""Pyro RQL server

"""

__docformat__ = "restructuredtext en"

import os

import sys

import select

import warnings

from time import localtime, mktime

from cubicweb.cwconfig import CubicWebConfiguration

from cubicweb.server.repository import Repository

class Finished(Exception):

    """raise to remove an event from the event loop"""

class TimeEvent:

    """base event"""

    # timefunc = staticmethod(localtime)

    timefunc = localtime

    def __init__(self, absolute=None, period=None):

        # local time tuple

        if absolute is None:

            absolute = self.timefunc()

        self.absolute = absolute

        # optional period in seconds

        self.period = period

    def is_ready(self):

        """return  true if the event is ready to be fired"""

        now = self.timefunc()

        if self.absolute < now:

            return True

        return False

    def fire(self, server):

        """fire the event

        must be overridden by concrete events

        """

        raise NotImplementedError()

    def update(self):

        """update the absolute date for the event or raise a finished exception

        """

        if self.period is None:

            raise Finished

        self.absolute = localtime(mktime(self.absolute) + self.period)

class QuitEvent(TimeEvent):

    """stop the server"""

    def fire(self, server):

        server.repo.shutdown()

        server.quiting = True

class RepositoryServer(object):

    def __init__(self, config, debug=False):

        """make the repository available as a PyRO object"""

        self.config = config

        self.repo = Repository(config, debug=debug)

        self.ns = None

        self.quiting = None

        # event queue

        self.events = []

        # start repository looping tasks

    def add_event(self, event):

        """add an event to the loop"""

        self.info('adding event %s', event)

        self.events.append(event)

    def trigger_events(self):

        """trigger ready events"""

        for event in self.events[:]:

            if event.is_ready():

                self.info('starting event %s', event)

                event.fire(self)

                try:

                    event.update()

                except Finished:

                    self.events.remove(event)

    def run(self, req_timeout=5.0):

        """enter the service loop"""

        self.repo.start_looping_tasks()

        while self.quiting is None:

            try:

                self.daemon.handleRequests(req_timeout)

            except select.error:

                continue

            self.trigger_events()

    def quit(self):

        """stop the server"""

        self.add_event(QuitEvent())

    def connect(self, host='', port=0):

        """the connect method on the repository only register to pyro if

        necessary

        """

        self.daemon = self.repo.pyro_register(host)

    # server utilitities ######################################################

    def install_sig_handlers(self):

        """install signal handlers"""

        import signal

        self.info('installing signal handlers')

        signal.signal(signal.SIGINT, lambda x, y, s=self: s.quit())

        signal.signal(signal.SIGTERM, lambda x, y, s=self: s.quit())

    def daemonize(self, pid_file=None):

        """daemonize the process"""

        # fork so the parent can exist

        if (os.fork()):

            return -1

        # deconnect from tty and create a new session

        os.setsid()

        # fork again so the parent, (the session group leader), can exit.

        # as a non-session group leader, we can never regain a controlling

        # terminal.

        if (os.fork()):

            return -1

        # move to the root to avoit mount pb

        os.chdir('/')

        # set paranoid umask

        os.umask(077)

        if pid_file is not None:

            # write pid in a file

            f = open(pid_file, 'w')

            f.write(str(os.getpid()))

            f.close()

        # filter warnings

        warnings.filterwarnings('ignore')

        # close standard descriptors

        sys.stdin.close()

        sys.stdout.close()

        sys.stderr.close()

from logging import getLogger

from cubicweb import set_log_methods

LOGGER = getLogger('cubicweb.reposerver')

set_log_methods(CubicWebConfiguration, LOGGER)