# Copyright (c) 2018 Cisco and/or its affiliates.
# 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.

"""Routing utilities library."""

from resources.libraries.python.VatExecutor import VatTerminal
from resources.libraries.python.topology import Topology
from resources.libraries.python.ssh import exec_cmd_no_error


class Routing(object):
    """Routing utilities."""

    @staticmethod
    def vpp_route_add(node, network, prefix_len, **kwargs):
        """Add route to the VPP node.

        :param node: Node to add route on.
        :param network: Route destination network address.
        :param prefix_len: Route destination network prefix length.
        :param kwargs: Optional key-value arguments:

            gateway: Route gateway address. (str)
            interface: Route interface. (str)
            vrf: VRF table ID. (int)
            use_sw_index: Use sw_if_index in VAT command. (bool)
            resolve_attempts: Resolve attempts IP route add parameter. (int)
            count: number of IP addresses to add starting from network IP (int)
            local: The route is local with same prefix (increment is 1).
                If None, then is not used. (bool)
            lookup_vrf: VRF table ID for lookup. (int)
            multipath: Enable multipath routing. (bool)
            weight: Weight value for unequal cost multipath routing. (int)

        :type node: dict
        :type network: str
        :type prefix_len: int
        :type kwargs: dict
        """

        gateway = kwargs.get("gateway", '')
        intf = kwargs.get("interface", '')
        use_sw_index = kwargs.get("use_sw_index", True)
        resolve_attempts = kwargs.get("resolve_attempts", 10)
        count = kwargs.get("count", 1)
        vrf = kwargs.get("vrf", None)
        l_vrf = kwargs.get("lookup_vrf", None)
        multipath = kwargs.get("multipath", False)
        weight = kwargs.get("weight", None)
        local = kwargs.get("local", False)

        if intf:
            if use_sw_index:
                int_cmd = ('sw_if_index {}'.
                           format(Topology.get_interface_sw_index(node, intf)))
            else:
                int_cmd = intf
        else:
            int_cmd = ''

        with VatTerminal(node, json_param=False) as vat:
            vat.vat_terminal_exec_cmd_from_template(
                'add_route.vat',
                network=network,
                prefix_length=prefix_len,
                via='via {}'.format(gateway) if gateway else '',
                vrf='vrf {}'.format(vrf) if vrf else '',
                interface=int_cmd,
                resolve_attempts='resolve-attempts {}'.
                format(resolve_attempts) if resolve_attempts else '',
                count='count {}'.format(count) if count else '',
                lookup_vrf='lookup-in-vrf {}'.format(l_vrf) if l_vrf else '',
                multipath='multipath' if multipath else '',
                weight='weight {}'.format(weight) if weight else '',
                local='local' if local else '')

    @staticmethod
    def add_fib_table(node, table_id, ipv6=False):
        """Create new FIB table according to ID.

        :param node: Node to add FIB on.
        :param table_id: FIB table ID.
        :param ipv6: Is this an IPv6 table
        :type node: dict
        :type table_id: int
        :type ipv6: bool
        """
        with VatTerminal(node) as vat:
            vat.vat_terminal_exec_cmd_from_template('add_fib_table.vat',
                                                    table_id=table_id,
                                                    ipv6="ipv6" if ipv6 else "")

    @staticmethod
    def add_route(node, ip_addr, prefix, gateway, namespace=None):
        """Add route in namespace.

        :param node: Node where to execute command.
        :param ip_addr: Route destination IP address.
        :param prefix: IP prefix.
        :param namespace: Execute command in namespace. Optional.
        :param gateway: Gateway address.
        :type node: dict
        :type ip_addr: str
        :type prefix: int
        :type gateway: str
        :type namespace: str
        """
        if namespace is not None:
            cmd = 'ip netns exec {} ip route add {}/{} via {}'.format(
                namespace, ip_addr, prefix, gateway)
        else:
            cmd = 'ip route add {}/{} via {}'.format(ip_addr, prefix, gateway)
        exec_cmd_no_error(node, cmd, sudo=True)