# Copyright (c) 2016 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.

"""Performance testing traffic generator library."""

from robot.api import logger

from resources.libraries.python.ssh import SSH
from resources.libraries.python.topology import NodeType
from resources.libraries.python.topology import NodeSubTypeTG
from resources.libraries.python.topology import Topology

__all__ = ['TrafficGenerator']

class TrafficGenerator(object):
    """Traffic Generator"""

    def __init__(self):
        self._result = None
        self._loss = None
        self._sent = None
        self._received = None
        #T-REX interface order mapping
        self._ifaces_reordered = 0

    def initialize_traffic_generator(self, node, interface1, interface2, test_type):
        """TG initialization
        :param node: Traffic generator node
        :param interface1: interface name of first interface
        :param interface2: interface name of second interface
        :test_type: 'L2' or 'L3' - src/dst MAC address
        :type node: dict
        :type interface1: str
        :type interface2: str
        :type test_type: str
        :return: nothing
        """

        trex_path = "/opt/trex-core-1.91"

        topo = Topology()

        if node['type'] != NodeType.TG:
            raise Exception('Node type is not a TG')
        if node['subtype'] == NodeSubTypeTG.TREX:
            ssh = SSH()
            ssh.connect(node)

            iface1_pci = topo.get_interface_pci_addr(node, interface1)
            iface2_pci = topo.get_interface_pci_addr(node, interface2)
            iface1_mac = topo.get_interface_mac(node, interface1)
            iface2_mac = topo.get_interface_mac(node, interface2)
            if min(iface1_pci, iface2_pci) != iface1_pci:
                iface1_mac, iface2_mac = iface2_mac, iface1_mac
                iface1_pci, iface2_pci = iface2_pci, iface1_pci
                self._ifaces_reordered = 1

            iface1_mac_hex = "0x"+iface1_mac.replace(":", ",0x")
            iface2_mac_hex = "0x"+iface2_mac.replace(":", ",0x")

            if test_type == 'L2':
                (ret, stdout, stderr) = ssh.exec_command(
                    "sudo sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
                    "- port_limit      : 2\n"
                    "  version         : 2\n"
                    "  interfaces      : [\"{}\",\"{}\"]\n"
                    "  port_info       :\n"
                    "          - dest_mac        :   [{}]\n"
                    "            src_mac         :   [{}]\n"
                    "          - dest_mac        :   [{}]\n"
                    "            src_mac         :   [{}]\n"
                    "EOF'"\
                    .format(iface1_pci, iface2_pci,
                            iface2_mac_hex, iface1_mac_hex,
                            iface1_mac_hex, iface2_mac_hex))
                if int(ret) != 0:
                    logger.error("failed to create t-rex config: {}"\
                    .format(stdout + stderr))
                    raise RuntimeError('trex config generation error')
            elif test_type == 'L3':
                raise NotImplementedError("L3 test_type not supported")
            else:
                raise Exception("test_type unknown")


            (ret, stdout, stderr) = ssh.exec_command(
                "sh -c 'cd {0}/scripts/ && "
                "sudo ./trex-cfg'"\
                .format(trex_path))
            if int(ret) != 0:
                logger.error('trex-cfg failed: {0}'.format(stdout + stderr))
                raise RuntimeError('trex-cfg failed')

            (ret, _, _) = ssh.exec_command(
                "sh -c 'cd {0}/scripts/ && "
                "sudo nohup ./t-rex-64 -i -c 4 --iom 0 > /dev/null 2>&1 &'"
                "> /dev/null"\
                .format(trex_path))
            if int(ret) != 0:
                raise RuntimeError('t-rex-64 startup failed')

    @staticmethod
    def teardown_traffic_generator(node):
        """TG teardown
        :param node: Traffic generator node
        :type node: dict
        :return: nothing
        """

        if node['type'] != NodeType.TG:
            raise Exception('Node type is not a TG')
        if node['subtype'] == NodeSubTypeTG.TREX:
            ssh = SSH()
            ssh.connect(node)
            (ret, stdout, stderr) = ssh.exec_command(
                "sh -c 'sudo pkill t-rex'")

    def send_traffic_on(self, nodes_info, duration, rate,
                        framesize, traffic_type):
        """Send traffic from all configured interfaces on TG
        :param nodes_info: Dictionary containing information on all nodes
        in topology.
        :param duration: Duration of test traffic generation in seconds
        :param rate: Offered load per interface (e.g. 1%, 3gbps, 4mpps, ...)
        :param framesize: Frame size (L2) in Bytes
        :param traffic_type: Traffic profile
        :type nodes_info: dict
        :type duration: str
        :type rate: str
        :type framesize: str
        :type traffic_type: str
        :return: TG output
        :rtype: str
        """

        node = nodes_info["TG"]

        if node['type'] != NodeType.TG:
            raise Exception('Node type is not a TG')

        if node['subtype'] is None:
            raise Exception('TG subtype not defined')

        ssh = SSH()
        ssh.connect(node)

        if node['subtype'] == NodeSubTypeTG.TREX:
            if traffic_type in ["3-node-xconnect", "3-node-bridge"]:
                (ret, stdout, stderr) = ssh.exec_command(
                    "sh -c '/tmp/openvpp-testing/resources/tools/t-rex/t-rex-stateless.py "
                    "-d {0} -r {1} -s {2} "
                    "--p1_src_start_ip 10.10.10.1 "
                    "--p1_src_end_ip 10.10.10.254 "
                    "--p1_dst_start_ip 20.20.20.1 "
                    "--p2_src_start_ip 20.20.20.1 "
                    "--p2_src_end_ip 20.20.20.254 "
                    "--p2_dst_start_ip 10.10.10.1'".\
                    format(duration, rate, framesize), timeout=int(duration)+60)
            elif traffic_type in ["3-node-IPv4"]:
                (ret, stdout, stderr) = ssh.exec_command(
                    "sh -c '/tmp/openvpp-testing/resources/tools/t-rex/t-rex-stateless.py "
                    "-d {0} -r {1} -s {2} "
                    "--p1_src_start_ip 10.10.10.2 "
                    "--p1_src_end_ip 10.10.10.254 "
                    "--p1_dst_start_ip 20.20.20.2 "
                    "--p2_src_start_ip 20.20.20.2 "
                    "--p2_src_end_ip 20.20.20.254 "
                    "--p2_dst_start_ip 10.10.10.2'".\
                    format(duration, rate, framesize),\
                    timeout=int(duration)+60)
            else:
                raise NotImplementedError('Unsupported traffic type')

        else:
            raise NotImplementedError("TG subtype not supported")

        logger.trace(ret)
        logger.trace(stdout)
        logger.trace(stderr)

        for line in stdout.splitlines():
            pass

        self._result = line
        logger.info('TrafficGen result: {0}'.format(self._result))

        self._loss = self._result.split(', ')[3].split('=')[1]

        return self._result

    def no_traffic_loss_occured(self):
        """Fail is loss occured in traffic run
        :return: nothing
        """

        if self._loss is None:
            raise Exception('The traffic generation has not been issued')
        if self._loss != '0':
            raise Exception('Traffic loss occured: {0}'.format(self._loss))