import os
import base64
import struct
import socket
from collections import defaultdict
from netaddr import IPAddress, IPNetwork
from django.db.models import F, Q
from xos.config import Config
from synchronizers.base.openstacksyncstep import OpenStackSyncStep
from synchronizers.base.syncstep import *
from core.models.network import *
from core.models.slice import *
from core.models.instance import Instance
from xos.logger import observer_logger as logger
from synchronizers.base.ansible import *
from openstack.driver import OpenStackDriver
from xos.config import Config
import json

import pdb

class SyncControllerNetworks(OpenStackSyncStep):
    requested_interval = 0
    provides=[Network]
    observes=ControllerNetwork
    playbook='sync_controller_networks.yaml'

    def alloc_subnet(self, uuid):
        # 16 bits only
        uuid_masked = uuid & 0xffff
        a = 10
        b = uuid_masked >> 8
        c = uuid_masked & 0xff
        d = 0

        cidr = '%d.%d.%d.%d/24'%(a,b,c,d)
        return cidr

    def alloc_gateway(self, subnet):
        # given a CIDR, allocate a default gateway using the .1 address within
        # the subnet.
        #    10.123.0.0/24 --> 10.123.0.1
        #    207.141.192.128/28 --> 207.141.192.129
        (network, bits) = subnet.split("/")
        network=network.strip()
        bits=int(bits.strip())
        netmask = (~(pow(2,32-bits)-1) & 0xFFFFFFFF)
        ip = struct.unpack("!L", socket.inet_aton(network))[0]
        ip = ip & netmask | 1
        return socket.inet_ntoa(struct.pack("!L", ip))

    def save_controller_network(self, controller_network):
        network_name = controller_network.network.name
        subnet_name = '%s-%d'%(network_name,controller_network.pk)
        if controller_network.subnet and controller_network.subnet.strip():
            # If a subnet is already specified (pass in by the creator), then
            # use that rather than auto-generating one.
            cidr = controller_network.subnet.strip()
        else:
            cidr = self.alloc_subnet(controller_network.pk)
        self.cidr=cidr
        slice = controller_network.network.owner

        # (VTN only) A primary network is one with an external gateway.
        # For now we set it to True for all but the management network.
        # In future we may want to make it an attribute of a Network.
        use_vtn = getattr(Config(), "networking_use_vtn", False)
        if use_vtn:
            primary = not network_name.startswith("management")
        else:
            primary = False

        network_fields = {'endpoint':controller_network.controller.auth_url,
                    'endpoint_v3': controller_network.controller.auth_url_v3,
                    'admin_user':slice.creator.email,
                    'tenant_name':slice.name,
                    'admin_password':slice.creator.remote_password,
                    'domain': controller_network.controller.domain,
                    'name':network_name,
                    'subnet_name':subnet_name,
                    'ansible_tag':'%s-%s@%s'%(network_name,slice.slicename,controller_network.controller.name),
                    'cidr':cidr,
                    'gateway':self.alloc_gateway(cidr),
                    'primary':primary,
                    'delete':False
                    }
        return network_fields

    def map_sync_outputs(self, controller_network,res):
        network_id = res[0]['id']
        subnet_id = res[1]['id']
        controller_network.net_id = network_id
        controller_network.subnet = self.cidr
        controller_network.subnet_id = subnet_id
	controller_network.backend_status = '1 - OK'
        controller_network.save()


    def map_sync_inputs(self, controller_network):
        # XXX This check should really be made from booleans, rather than using hardcoded network names
        #if (controller_network.network.template.name not in ['Private', 'Private-Indirect', 'Private-Direct', 'management_template'):
        #    logger.info("skipping network controller %s because it is not private" % controller_network)
        #    # We only sync private networks
        #    return SyncStep.SYNC_WITHOUT_RUNNING

        # hopefully a better approach than above
        if (controller_network.network.template.shared_network_name or controller_network.network.template.shared_network_id):
            return SyncStep.SYNC_WITHOUT_RUNNING

        if not controller_network.controller.admin_user:
            logger.info("controller %r has no admin_user, skipping" % controller_network.controller)
            return

        if controller_network.network.owner and controller_network.network.owner.creator:
	    return self.save_controller_network(controller_network)
        else:
            raise Exception('Could not save network controller %s'%controller_network)

    def map_delete_inputs(self, controller_network):
        # XXX This check should really be made from booleans, rather than using hardcoded network names
	if (controller_network.network.template.name not in ['Private', 'Private-Indirect', 'Private-Direct']):
            # We only sync private networks
            return
	try:
        	slice = controller_network.network.owner # XXX: FIXME!!
        except:
                raise Exception('Could not get slice for Network %s'%controller_network.network.name)

	network_name = controller_network.network.name
        subnet_name = '%s-%d'%(network_name,controller_network.pk)
	cidr = controller_network.subnet
	network_fields = {'endpoint':controller_network.controller.auth_url,
                    'admin_user':slice.creator.email, # XXX: FIXME
                    'tenant_name':slice.name, # XXX: FIXME
                    'admin_password':slice.creator.remote_password,
                    'name':network_name,
                    'subnet_name':subnet_name,
                    'ansible_tag':'%s-%s@%s'%(network_name,slice.slicename,controller_network.controller.name),
                    'cidr':cidr,
		    'delete':True
                    }

        return network_fields

	"""
        driver = OpenStackDriver().client_driver(caller=controller_network.network.owner.creator,
                                                 tenant=controller_network.network.owner.name,
                                                 controller=controller_network.controller.name)
        if (controller_network.router_id) and (controller_network.subnet_id):
            driver.delete_router_interface(controller_network.router_id, controller_network.subnet_id)
        if controller_network.subnet_id:
            driver.delete_subnet(controller_network.subnet_id)
        if controller_network.router_id:
            driver.delete_router(controller_network.router_id)
        if controller_network.net_id:
            driver.delete_network(controller_network.net_id)
	"""