import os
import base64
from collections import defaultdict
from netaddr import IPAddress, IPNetwork
from django.db.models import F, Q
from planetstack.config import Config
from observer.openstacksyncstep import OpenStackSyncStep
from core.models.site import Deployment, SiteDeployments
from core.models.slice import Slice, SliceDeployments
from core.models.userdeployments import UserDeployments
from util.logger import Logger, logging

logger = Logger(level=logging.INFO)

class SyncSliceDeployments(OpenStackSyncStep):
    provides=[SliceDeployments]
    requested_interval=0

    def fetch_pending(self, deleted):
        if (deleted):
            return SliceDeployments.deleted_objects.all()
        else:
            # slice deployments are not visible to users. We must ensure
            # slices are deployed at all deploymets available to their site.
            site_deployments = SiteDeployments.objects.all()
            site_deploy_lookup = defaultdict(list)
            for site_deployment in site_deployments:
                site_deploy_lookup[site_deployment.site].append(site_deployment.deployment)
            
            slice_deployments = SliceDeployments.objects.all()
            slice_deploy_lookup = defaultdict(list)
            for slice_deployment in slice_deployments:
                slice_deploy_lookup[slice_deployment.slice].append(slice_deployment.deployment)
            
            all_deployments = Deployment.objects.all() 
            for slice in Slice.objects.all():
                # slices are added to all deployments for now
                expected_deployments = all_deployments
                #expected_deployments = site_deploy_lookup[slice.site]
                for expected_deployment in expected_deployments:
                    if slice not in slice_deploy_lookup or \
                       expected_deployment not in slice_deploy_lookup[slice]:
                        sd = SliceDeployments(slice=slice, deployment=expected_deployment)
                        sd.save()

            # now we can return all slice deployments that need to be enacted   
            return SliceDeployments.objects.filter(Q(enacted__lt=F('updated')) | Q(enacted=None))

    def get_next_subnet(self, deployment=None):
        # limit ourself to 10.0.x.x for now
        valid_subnet = lambda net: net.startswith('10.0')
        driver = self.driver.admin_driver(deployment=deployment)
        subnets = driver.shell.quantum.list_subnets()['subnets']
        ints = [int(IPNetwork(subnet['cidr']).ip) for subnet in subnets \
                if valid_subnet(subnet['cidr'])]
        ints.sort()
        if ints:
            last_ip = IPAddress(ints[-1])
        else:
            last_ip = IPAddress('10.0.0.1')
        last_ip = IPAddress(ints[-1])
        last_network = IPNetwork(str(last_ip) + "/24")
        next_network = IPNetwork(str(IPAddress(last_network) + last_network.size) + "/24")
        return next_network


    def sync_record(self, slice_deployment):
        logger.info("sync'ing slice deployment %s" % slice_deployment)
        if not slice_deployment.tenant_id:
            nova_fields = {'tenant_name': slice_deployment.slice.name,
                   'description': slice_deployment.slice.description,
                   'enabled': slice_deployment.slice.enabled}
            driver = self.driver.admin_driver(deployment=slice_deployment.deployment.name)
            tenant = driver.create_tenant(**nova_fields)
            slice_deployment.tenant_id = tenant.id

            # XXX give caller an admin role at the tenant they've created
            deployment_users = UserDeployments.objects.filter(user=slice_deployment.slice.creator,
                                                             deployment=slice_deployment.deployment)            
            if not deployment_users:
                logger.info("slice createor %s has not accout at deployment %s" % (slice_deployment.slice.creator, slice_deployment.deployment.name))
            else:
                deployment_user = deployment_users[0]
                # lookup user id at this deployment
                kuser= driver.shell.keystone.users.find(email=slice_deployment.slice.creator.email)

                # add required roles at the slice's tenant 
                driver.add_user_role(kuser.id, tenant.id, 'admin')
                    
                # refresh credentials using this tenant
                client_driver = self.driver.client_driver(caller=deployment_user.user,
                                                          tenant=tenant.name, 
                                                          deployment=slice_deployment.deployment.name)


        if slice_deployment.id and slice_deployment.tenant_id:
            # update existing tenant
            driver = self.driver.admin_driver(deployment=slice_deployment.deployment.name)
            driver.update_tenant(slice_deployment.tenant_id,
                                 description=slice_deployment.slice.description,
                                 enabled=slice_deployment.slice.enabled)  

        if slice_deployment.tenant_id:
            # update slice/tenant quota
            driver = self.driver.client_driver(deployment=slice_deployment.deployment.name, tenant=slice_deployment.slice.name)
            driver.shell.nova.quotas.update(tenant_id=slice_deployment.tenant_id, instances=int(slice_deployment.slice.max_slivers)) 

        slice_deployment.save()


    def delete_record(self, slice_deployment):
        user = User.objects.get(id=slice_deployment.slice.creator.id)
        driver = OpenStackDriver().admin_driver(deployment=slice_deployment.deployment.name)
        client_driver = driver.client_driver(caller=user,
                                             tenant=slice_deployment.slice.name,
                                             deployment=slice_deployment.deployment.name)

        if slice_deployment.router_id and slice_deployment.subnet_id:
            client_driver.delete_router_interface(slice_deployment.router_id, slice_deployment.subnet_id)
        if slice_deployment.subnet_id:
            client_driver.delete_subnet(slice_deployment.subnet_id)
        if slice_deployment.router_id:    
            client_driver.delete_router(slice_deployment.router_id)
        if slice_deployment.network_id:
            client_driver.delete_network(slice_deployment.network_id)
        if slice_deployment.tenant_id:
            driver.delete_tenant(slice_deployment.tenant_id)
        # delete external route
        #subnet = None
        #subnets = client_driver.shell.quantum.list_subnets()['subnets']
        #for snet in subnets:
        #    if snet['id'] == slice_deployment.subnet_id:
        #        subnet = snet
        #if subnet:
        #    driver.delete_external_route(subnet)