import hashlib
import os
import socket
import sys
import base64
import time
from django.db.models import F, Q
from xos.config import Config
from observer.syncstep import SyncStep
from observer.ansible import run_template_ssh
from core.models import Service, Slice
from cord.models import VCPEService, VCPETenant, VOLTTenant
from hpc.models import HpcService, CDNPrefix
from util.logger import Logger, logging

# hpclibrary will be in steps/..
parentdir = os.path.join(os.path.dirname(__file__),"..")
sys.path.insert(0,parentdir)

from broadbandshield import BBS

logger = Logger(level=logging.INFO)

class SyncVCPETenant(SyncStep):
    provides=[VCPETenant]
    observes=VCPETenant
    requested_interval=0
    template_name = "sync_vcpetenant.yaml"
    service_key_name = "/opt/xos/observers/vcpe/vcpe_private_key"

    def __init__(self, **args):
        SyncStep.__init__(self, **args)

    def defer_sync(self, o, reason):
        logger.info("defer object %s due to %s" % (str(o), reason))
        raise Exception("defer object %s due to %s" % (str(o), reason))

    def fetch_pending(self, deleted):
        if (not deleted):
            objs = VCPETenant.get_tenant_objects().filter(Q(enacted__lt=F('updated')) | Q(enacted=None),Q(lazy_blocked=False))
        else:
            objs = VCPETenant.get_deleted_tenant_objects()

        return objs

    def get_vcpe_service(self, o):
        if not o.provider_service:
            return None

        vcpes = VCPEService.get_service_objects().filter(id=o.provider_service.id)
        if not vcpes:
            return None

        return vcpes[0]

    def get_extra_attributes(self, o):
        # This is a place to include extra attributes that aren't part of the
        # object itself. In the case of vCPE, we need to know:
        #   1) the addresses of dnsdemux, to setup dnsmasq in the vCPE
        #   2) CDN prefixes, so we know what URLs to send to dnsdemux
        #   3) BroadBandShield server addresses, for parental filtering
        #   4) vlan_ids, for setting up networking in the vCPE VM

        vcpe_service = self.get_vcpe_service(o)

        dnsdemux_ip = None
        if vcpe_service.backend_network_label:
            # Connect to dnsdemux using the network specified by
            #     vcpe_service.backend_network_label
            for service in HpcService.objects.all():
                for slice in service.slices.all():
                    if "dnsdemux" in slice.name:
                        for sliver in slice.slivers.all():
                            for ns in sliver.networkslivers.all():
                                if ns.ip and ns.network.labels and (vcpe_service.backend_network_label in ns.network.labels):
                                    dnsdemux_ip = ns.ip
            if not dnsdemux_ip:
                logger.info("failed to find a dnsdemux on network %s" % vcpe_service.backend_network_label)
        else:
            # Connect to dnsdemux using the sliver's public address
            for service in HpcService.objects.all():
                for slice in service.slices.all():
                    if "dnsdemux" in slice.name:
                        for sliver in slice.slivers.all():
                            if dnsdemux_ip=="none":
                                try:
                                    dnsdemux_ip = socket.gethostbyname(sliver.node.name)
                                except:
                                    pass
            if not dnsdemux_ip:
                logger.info("failed to find a dnsdemux with a public address")

        dnsdemux_ip = dnsdemux_ip or "none"

        cdn_prefixes = []
        for prefix in CDNPrefix.objects.all():
            cdn_prefixes.append(prefix.prefix)

        bbs_addrs = []
        if vcpe_service.bbs_slice:
            bbs_slice = vcpe_service.bbs_slice
            for bbs_sliver in bbs_slice.slivers.all():
                for ns in bbs_sliver.networkslivers.all():
                    if ns.ip and ns.network.labels and ("hpc_client" in ns.network.labels):
                        bbs_addrs.append(ns.ip)
        elif vcpe.bbs_server:
            bbs_addrs.append(vcpe.bbs_server)
        else:
            logger.info("neither bbs_slice nor bbs_server is configured in the vCPE")

        vlan_ids = []
        if o.volt:
            vlan_ids.append(o.volt.vlan_id)

        return {"vlan_ids": vlan_ids,
                "dnsdemux_ip": dnsdemux_ip,
                "cdn_prefixes": cdn_prefixes,
                "bbs_addrs": bbs_addrs}

    def get_sliver(self, o):
        # We need to know what slivers is associated with the object.
        # For vCPE this is easy, as VCPETenant has a sliver field.

        return o.sliver

    def sync_record(self, o):
        logger.info("sync'ing VCPETenant %s" % str(o))

        sliver = self.get_sliver(o)
        if not sliver:
            self.defer_sync(o, "waiting on sliver")
            return

        service = self.get_vcpe_service(o)
        if not service:
            # Ansible uses the service's keypair in order to SSH into the
            # instance. It would be bad if the slice had no service.

            raise Exception("Slice %s is not associated with a service" % sliver.slice.name)

        # Make sure the slice is configured properly
        if (service != o.sliver.slice.service):
            raise Exception("Slice %s is associated with some service that is not %s" % (str(sliver.slice), str(service)))

        if not os.path.exists(self.service_key_name):
            raise Exception("Service key %s does not exist" % self.service_key_name)

        service_key = file(self.service_key_name).read()

        fields = { "sliver_name": sliver.name,
                   "hostname": sliver.node.name,
                   "instance_id": sliver.instance_id,
                   "private_key": service_key,
                   "ansible_tag": "vcpe_tenant_" + str(o.id)
                 }

        # for attributes that come from VCPETenant
        if hasattr(o, "sync_attributes"):
            for attribute_name in o.sync_attributes:
                fields[attribute_name] = getattr(o, attribute_name)

        # only enable filtering if we have a subscriber object (see below)
        url_filter_enable = False

        # for attributes that come from CordSubscriberRoot
        if o.volt and o.volt.subscriber and hasattr(o.volt.subscriber, "sync_attributes"):
            for attribute_name in o.volt.subscriber.sync_attributes:
                fields[attribute_name] = getattr(o.volt.subscriber, attribute_name)
            url_filter_enable = o.volt.subscriber.url_filter_enable
            url_filter_level = o.volt.subscriber.url_filter_level
            url_filter_users = o.volt.subscriber.users

        fields.update(self.get_extra_attributes(o))

        ansible_hash = hashlib.md5(repr(sorted(fields.items()))).hexdigest()
        quick_update = (o.last_ansible_hash == ansible_hash)

        if quick_update:
            logger.info("quick_update triggered; skipping ansible recipe")
        else:
            tStart = time.time()
            run_template_ssh(self.template_name, fields)
            logger.info("playbook execution time %d" % int(time.time()-tStart))

        if url_filter_enable:
            bbs_hostname = None
            if service.bbs_api_hostname and service.bbs_api_port:
                bbs_hostname = service.bbs_api_hostname
            else:
                # TODO: extract from slice
                bbs_hostname = "cordcompute01.onlab.us"

            if service.bbs_api_port:
                bbs_port = service.bbs_api_port
            else:
                bbs_port = 8018

            if not bbs_hostname:
                logger.info("broadbandshield is not configured")
            else:
                tStart = time.time()
                bbs = BBS(o.bbs_account, "123", bbs_hostname, bbs_port)
                bbs.sync(url_filter_level, url_filter_users)

                if o.hpc_client_ip:
                    logger.info("associate account %s with ip %s" % (o.bbs_account, o.hpc_client_ip))
                    bbs.associate(o.hpc_client_ip)
                else:
                    logger.info("no hpc_client_ip to associate")

                logger.info("bbs update time %d" % int(time.time()-tStart))

        o.last_ansible_hash = ansible_hash
        o.save()

    def delete_record(self, m):
        pass