# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright 2012 NEC Corporation.  All rights reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.
# @author: Ryota MIBU
# @author: Akihiro MOTOKI

import re
import uuid

from quantum.plugins.nec.db import api as ndb
from quantum.plugins.nec.common import ofc_client
from quantum.plugins.nec import ofc_driver_base


class PFCDriverBase(ofc_driver_base.OFCDriverBase):
    """Base Class for PDC Drivers

    PFCDriverBase provides methods to handle PFC resources through REST API.
    This uses ofc resource path instead of ofc resource ID.

    The class implements the API for PFC V4.0 or later.
    """

    def __init__(self, conf_ofc):
        self.client = ofc_client.OFCClient(host=conf_ofc.host,
                                           port=conf_ofc.port,
                                           use_ssl=conf_ofc.use_ssl,
                                           key_file=conf_ofc.key_file,
                                           cert_file=conf_ofc.cert_file)

    @classmethod
    def filter_supported(cls):
        return False

    def _generate_pfc_str(self, raw_str):
        """Generate PFC acceptable String"""
        return re.sub(r'[^0-9a-zA-Z]', '_', raw_str)

    def _generate_pfc_id(self, id_str):
        """Generate ID on PFC

        Currently, PFC ID must be less than 32.
        Shorten UUID string length from 36 to 31 by follows:
          * delete UUID Version and hyphen (see RFC4122)
          * ensure str length
        """
        try:
            # openstack.common.uuidutils.is_uuid_like() returns
            # False for KeyStone tenant_id, so uuid.UUID is used
            # directly here to accept tenant_id as UUID string
            uuid_str = str(uuid.UUID(id_str)).replace('-', '')
            uuid_no_version = uuid_str[:12] + uuid_str[13:]
            return uuid_no_version[:31]
        except:
            return self._generate_pfc_str(id_str)[:31]

    def _generate_pfc_description(self, desc):
        """Generate Description on PFC

        Currently, PFC Description must be less than 128.
        """
        return self._generate_pfc_str(desc)[:127]

    def create_tenant(self, description, tenant_id=None):
        ofc_tenant_id = self._generate_pfc_id(tenant_id)
        body = {'id': ofc_tenant_id}
        res = self.client.post('/tenants', body=body)
        return '/tenants/' + ofc_tenant_id

    def delete_tenant(self, ofc_tenant_id):
        return self.client.delete(ofc_tenant_id)

    def create_network(self, ofc_tenant_id, description, network_id=None):
        path = "%s/networks" % ofc_tenant_id
        pfc_desc = self._generate_pfc_description(description)
        body = {'description': pfc_desc}
        res = self.client.post(path, body=body)
        ofc_network_id = res['id']
        return path + '/' + ofc_network_id

    def delete_network(self, ofc_network_id):
        return self.client.delete(ofc_network_id)

    def create_port(self, ofc_network_id, portinfo,
                    port_id=None):
        path = "%s/ports" % ofc_network_id
        body = {'datapath_id': portinfo.datapath_id,
                'port': str(portinfo.port_no),
                'vid': str(portinfo.vlan_id)}
        res = self.client.post(path, body=body)
        ofc_port_id = res['id']
        return path + '/' + ofc_port_id

    def delete_port(self, ofc_port_id):
        return self.client.delete(ofc_port_id)

    def convert_ofc_tenant_id(self, context, ofc_tenant_id):
        # If ofc_tenant_id starts with '/', it is already new-style
        if ofc_tenant_id[0] == '/':
            return ofc_tenant_id
        return '/tenants/%s' % ofc_tenant_id

    def convert_ofc_network_id(self, context, ofc_network_id, tenant_id):
        # If ofc_network_id starts with '/', it is already new-style
        if ofc_network_id[0] == '/':
            return ofc_network_id

        ofc_tenant_id = ndb.get_ofc_id_lookup_both(
            context.session, 'ofc_tenant', tenant_id)
        ofc_tenant_id = self.convert_ofc_tenant_id(context, ofc_tenant_id)
        params = dict(tenant=ofc_tenant_id, network=ofc_network_id)
        return '%(tenant)s/networks/%(network)s' % params

    def convert_ofc_port_id(self, context, ofc_port_id, tenant_id, network_id):
        # If ofc_port_id  starts with '/', it is already new-style
        if ofc_port_id[0] == '/':
            return ofc_port_id

        ofc_network_id = ndb.get_ofc_id_lookup_both(
            context.session, 'ofc_network', network_id)
        ofc_network_id = self.convert_ofc_network_id(
            context, ofc_network_id, tenant_id)
        params = dict(network=ofc_network_id, port=ofc_port_id)
        return '%(network)s/ports/%(port)s' % params


class PFCV3Driver(PFCDriverBase):

    def create_tenant(self, description, tenant_id):
        ofc_tenant_id = self._generate_pfc_id(tenant_id)
        return "/tenants/" + ofc_tenant_id

    def delete_tenant(self, ofc_tenant_id):
        pass


class PFCV4Driver(PFCDriverBase):
    pass