from django.db import models
from core.models import Service, PlCoreBase, Slice, Instance, Tenant, TenantWithContainer, Node, Image, User, Flavor, Subscriber, NetworkParameter, NetworkParameterType, Port, AddressPool
from core.models.plcorebase import StrippedCharField
import os
from django.db import models, transaction
from django.forms.models import model_to_dict
from django.db.models import Q
from operator import itemgetter, attrgetter, methodcaller
from core.models import Tag
from core.models.service import LeastLoadedNodeScheduler
import traceback
from xos.exceptions import *
from xos.config import Config


class ConfigurationError(Exception):
    pass


VROUTER_KIND = "vROUTER"
APP_LABEL = "vrouter"

# NOTE: don't change VROUTER_KIND unless you also change the reference to it
#   in tosca/resources/network.py

CORD_USE_VTN = getattr(Config(), "networking_use_vtn", False)


class VRouterService(Service):
    KIND = VROUTER_KIND

    class Meta:
        app_label = APP_LABEL
        verbose_name = "vRouter Service"

    # Are rest_hostname and rest_port redundant with ONOS service?
    # Should ONOSService be augmented with rest_user and rest_pass?

    rest_hostname = StrippedCharField(max_length=255, null=True, blank=True)
    rest_port = models.IntegerField(default=8181)
    rest_user = StrippedCharField(max_length=255, default="onos")
    rest_pass = StrippedCharField(max_length=255, default="rocks")

    def ip_to_mac(self, ip):
        (a, b, c, d) = ip.split('.')
        return "02:42:%02x:%02x:%02x:%02x" % (int(a), int(b), int(c), int(d))

    def get_gateways(self):
        gateways = []

        aps = self.addresspools.all()
        for ap in aps:
            gateways.append({"gateway_ip": ap.gateway_ip, "gateway_mac": ap.gateway_mac})

        return gateways

    def get_address_pool(self, name):
        ap = AddressPool.objects.filter(name=name, service=self)
        if not ap:
            raise Exception("vRouter unable to find addresspool %s" % name)
        return ap[0]

    def get_tenant(self, **kwargs):
        address_pool_name = kwargs.pop("address_pool_name")

        ap = self.get_address_pool(address_pool_name)

        ip = ap.get_address()
        if not ip:
            raise Exception("AddressPool '%s' has run out of addresses." % ap.name)

        t = VRouterTenant(provider_service=self, **kwargs)
        t.public_ip = ip
        t.public_mac = self.ip_to_mac(ip)
        t.address_pool_id = ap.id
        t.save()

        return t


class VRouterTenant(Tenant):
    class Meta:
        verbose_name = "vRouter Tenant"

    KIND = VROUTER_KIND

    public_ip = StrippedCharField(max_length = 30, null=True, blank=True)
    public_mac = StrippedCharField(max_length = 30, null=True, blank=True)
    address_pool = models.ForeignKey(AddressPool, related_name='vrouter_tenants', blank=True, null=True)

    @property
    def gateway_ip(self):
        if not self.address_pool:
            return None
        return self.address_pool.gateway_ip

    @property
    def gateway_mac(self):
        if not self.address_pool:
            return None
        return self.address_pool.gateway_mac

    @property
    def cidr(self):
        if not self.address_pool:
            return None
        return self.address_pool.cidr

    @property
    def netbits(self):
        # return number of bits in the network portion of the cidr
        if self.cidr:
            parts = self.cidr.split("/")
            if len(parts) == 2:
                return int(parts[1].strip())
        return None

    def cleanup_addresspool(self):
        if self.address_pool:
            ap = self.address_pool
            if ap:
                ap[0].put_address(self.public_ip)
                self.public_ip = None

    def delete(self, *args, **kwargs):
        self.cleanup_addresspool()
        super(VRouterTenant, self).delete(*args, **kwargs)


# DEVICES
class VRouterDevice(PlCoreBase):
    """define the information related to an device used by vRouter"""
    class Meta:
        app_label = APP_LABEL
        verbose_name = "vRouter Device"

    name = models.CharField(max_length=20, help_text="device friendly name", null=True, blank=True)
    openflow_id = models.CharField(max_length=20, help_text="device identifier in ONOS", null=False, blank=False)
    config_key = models.CharField(max_length=32, help_text="configuration key", null=False, blank=False, default="basic")
    driver = models.CharField(max_length=32, help_text="driver type", null=False, blank=False)
    vrouter_service = models.ForeignKey(VRouterService, related_name='devices')


# PORTS
class VRouterPort(PlCoreBase):
    class Meta:
        app_label = APP_LABEL
        verbose_name = "vRouter Port"

    name = models.CharField(max_length=20, help_text="port friendly name", null=True, blank=True)
    openflow_id = models.CharField(max_length=21, help_text="port identifier in ONOS", null=False, blank=False)
    vrouter_device = models.ForeignKey(VRouterDevice, related_name='ports')
    # NOTE probably is not meaningful to relate a port to a service
    vrouter_service = models.ForeignKey(VRouterService, related_name='device_ports')


class VRouterInterface(PlCoreBase):
    class Meta:
        app_label = APP_LABEL
        verbose_name = "vRouter Interface"

    name = models.CharField(max_length=20, help_text="interface friendly name", null=True, blank=True)
    vrouter_port = models.ForeignKey(VRouterPort, related_name='interfaces')
    name = models.CharField(max_length=10, help_text="interface name", null=False, blank=False)
    mac = models.CharField(max_length=17, help_text="interface mac", null=False, blank=False)
    vlan = models.CharField(max_length=10, help_text="interface vlan id", null=True, blank=True)


class VRouterIp(PlCoreBase):
    class Meta:
        app_label = APP_LABEL
        verbose_name = "vRouter Ip"

    name = models.CharField(max_length=20, help_text="ip friendly name", null=True, blank=True)
    vrouter_interface = models.ForeignKey(VRouterInterface, related_name='ips')
    ip = models.CharField(max_length=19, help_text="interface ips", null=False, blank=False)


# APPS
class VRouterApp(PlCoreBase):
    class Meta:
        app_label = "vrouter"
        verbose_name = "vRouter App"

    def _get_interfaces(self):
        app_interfaces = []
        devices = VRouterDevice.objects.filter(vrouter_service=self.vrouter_service)
        for device in devices:
            ports = VRouterPort.objects.filter(vrouter_device=device.id)
            for port in ports:
                interfaces = VRouterInterface.objects.filter(vrouter_port=port.id)
                for iface in interfaces:
                    app_interfaces.append(iface.name)
        return app_interfaces

    vrouter_service = models.ForeignKey(VRouterService, related_name='apps')
    name = models.CharField(max_length=50, help_text="application name", null=False, blank=False)
    control_plane_connect_point = models.CharField(max_length=21, help_text="port identifier in ONOS", null=False, blank=False)
    ospf_enabled = models.BooleanField(default=True, help_text="ospf enabled")
    interfaces = property(_get_interfaces)