#
#    NEPI, a framework to manage network experiments
#    Copyright (C) 2013 INRIA
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License version 2 as
#    published by the Free Software Foundation;
#
#    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/>.
#
# Author: Alina Quereilhac <alina.quereilhac@inria.fr>
#         Julien Tribino <julien.tribino@inria.fr>

from nepi.util.timefuncs import tnow
from nepi.execution.resource import ResourceManager, clsinit_copy, \
        ResourceState
from nepi.execution.attribute import Attribute, Flags 
from nepi.resources.omf.omf_resource import ResourceGateway, OMFResource
from nepi.resources.omf.omf_api_factory import OMFAPIFactory

import time

reschedule_check = "1s"
confirmation_counter = 3600

@clsinit_copy
class OMFNode(OMFResource):
    """
    .. class:: Class Args :
      
        :param ec: The Experiment controller
        :type ec: ExperimentController
        :param guid: guid of the RM
        :type guid: int
        :param creds: Credentials to communicate with the rm (XmppClient for OMF)
        :type creds: dict

    """
    _rtype = "omf::Node"
    _authorized_connections = ["omf::Application" , "omf::WifiInterface"]

    @classmethod
    def _register_attributes(cls):
        """Register the attributes of an OMF Node

        """
        hostname = Attribute("hostname", "Hostname of the machine")

        cls._register_attribute(hostname)

    # XXX: We don't necessary need to have the credentials at the 
    # moment we create the RM
    def __init__(self, ec, guid):
        """
        :param ec: The Experiment controller
        :type ec: ExperimentController
        :param guid: guid of the RM
        :type guid: int

        """
        super(OMFNode, self).__init__(ec, guid)

        self._omf_api = None 

        # For performance tests
        self.perf = True
        self.begin_deploy_time = None


    @property
    def exp_id(self):
        return self.ec.exp_id

    def valid_connection(self, guid):
        """ Check if the connection with the guid in parameter is possible. 
        Only meaningful connections are allowed.

        :param guid: Guid of the current RM
        :type guid: int
        :rtype:  Boolean

        """
        rm = self.ec.get_resource(guid)
        if rm.get_rtype() in self._authorized_connections:
            msg = "Connection between %s %s and %s %s accepted" % (
                    self.get_rtype(), self._guid, rm.get_rtype(), guid)
            self.debug(msg)
            return True

        msg = "Connection between %s %s and %s %s refused" % (
                self.get_rtype(), self._guid, rm.get_rtype(), guid)
        self.error(msg)

        return False

    def do_deploy(self):
        """ Deploy the RM. It means : Send Xmpp Message Using OMF protocol 
            to enroll the node into the experiment.

        """ 
      ## For performance test
        if self.perf:
            self.begin_deploy_time = tnow()
            self.perf = False

        if not self.get('xmppServer'):
            msg = "XmppServer is not initialzed. XMPP Connections impossible"
            self.error(msg)
            raise RuntimeError(msg)

        if not self.get('version'):
            msg = "Version of OMF is not indicated"
            self.error(msg)
            raise RuntimeError(msg)

        if not (self.get('xmppUser') or self.get('xmppPort') 
                   or self.get('xmppPassword')):
            msg = "Credentials are not all initialzed. Default values will be used"
            self.warn(msg)

        if not self._omf_api :
            self._omf_api = OMFAPIFactory.get_api(self.get('version'), 
              self.get('xmppServer'), self.get('xmppUser'), self.get('xmppPort'),
               self.get('xmppPassword'), exp_id = self.exp_id)

        if not self.get('hostname') :
            msg = "Hostname's value is not initialized"
            self.error(msg)
            raise RuntimeError(msg)

        if self.get('version') == "5":
            self._omf_api.enroll_host(self.get('hostname'))
        else:
            self._omf_api.enroll_topic(self.get('hostname'))

        super(OMFNode, self).do_deploy()

    def do_release(self):
        """ Clean the RM at the end of the experiment by unenrolling
        the node from the topic

        """
        from nepi.resources.omf.application import OMFApplication
        rm_list = self.get_connected(OMFApplication.get_rtype())
        if rm_list:
            for rm in rm_list:
                if rm.state < ResourceState.RELEASED:
                    self.ec.schedule(self.reschedule_delay, self.release)
                    return 

        from nepi.resources.omf.interface import OMFWifiInterface
        rm_list = self.get_connected(OMFWifiInterface.get_rtype())
        if rm_list:
            for rm in rm_list:
                if rm.state < ResourceState.RELEASED:
                    self.ec.schedule(self.reschedule_delay, self.release)
                    return 

        if self._omf_api:
            if self.get('version') == "5":
                self._omf_api.release(self.get('hostname'))
            else:
                self._omf_api.unenroll_topic(self.get('hostname'))

            OMFAPIFactory.release_api(self.get('version'), 
              self.get('xmppServer'), self.get('xmppUser'), self.get('xmppPort'),
               self.get('xmppPassword'), exp_id = self.exp_id)

        super(OMFNode, self).do_release()