# Copyright 2015-2016 Intel Corporation.
#
# 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.
"""TestCase base class
"""

import csv
import os
import logging
import subprocess
import copy
from collections import OrderedDict

from core.results.results_constants import ResultsConstants
import core.component_factory as component_factory
from core.loader import Loader
from tools import tasks
from tools import hugepages
from tools.report import report
from conf import settings as S
from tools.pkt_gen.trafficgen.trafficgenhelper import TRAFFIC_DEFAULTS
from conf import get_test_param

class TestCase(object):
    """TestCase base class

    In this basic form runs RFC2544 throughput test
    """
    def __init__(self, cfg, results_dir):
        """Pull out fields from test config

        :param cfg: A dictionary of string-value pairs describing the test
            configuration. Both the key and values strings use well-known
            values.
        :param results_dir: Where the csv formatted results are written.
        """
        self._hugepages_mounted = False
        self._logger = logging.getLogger(__name__)
        self.name = cfg['Name']
        self.desc = cfg.get('Description', 'No description given.')
        self.deployment = cfg['Deployment']
        self._frame_mod = cfg.get('Frame Modification', None)
        framerate = get_test_param('iload', None)
        if framerate == None:
            framerate = cfg.get('iLoad', 100)

        # identify guest loopback method, so it can be added into reports
        self.guest_loopback = []
        if self.deployment in ['pvp', 'pvvp']:
            guest_loopback = get_test_param('guest_loopback', None)
            if guest_loopback:
                self.guest_loopback.append(guest_loopback)
            else:
                if self.deployment == 'pvp':
                    self.guest_loopback.append(S.getValue('GUEST_LOOPBACK')[0])
                else:
                    self.guest_loopback = S.getValue('GUEST_LOOPBACK').copy()

        # read configuration of streams; CLI parameter takes precedence to
        # testcase definition
        multistream = cfg.get('MultiStream', 0)
        multistream = get_test_param('multistream', multistream)
        stream_type = cfg.get('Stream Type', 'L4')
        stream_type = get_test_param('stream_type', stream_type)
        pre_installed_flows = cfg.get('Pre-installed Flows', 'No')
        pre_installed_flows = get_test_param('pre-installed_flows', pre_installed_flows)


        # check if test requires background load and which generator it uses
        self._load_cfg = cfg.get('Load', None)
        if self._load_cfg and 'tool' in self._load_cfg:
            self._loadgen = self._load_cfg['tool']
        else:
            # background load is not requested, so use dummy implementation
            self._loadgen = "Dummy"

        if self._frame_mod:
            self._frame_mod = self._frame_mod.lower()
        self._results_dir = results_dir

        # set traffic details, so they can be passed to vswitch and traffic ctls
        self._traffic = copy.deepcopy(TRAFFIC_DEFAULTS)
        self._traffic.update({'traffic_type': cfg['Traffic Type'],
                              'flow_type': cfg.get('Flow Type', 'port'),
                              'bidir': cfg['biDirectional'],
                              'multistream': int(multistream),
                              'stream_type': stream_type,
                              'pre_installed_flows' : pre_installed_flows,
                              'frame_rate': int(framerate)})

        # OVS Vanilla requires guest VM MAC address and IPs to work
        if 'linux_bridge' in self.guest_loopback:
            self._traffic['l2'].update({'srcmac': S.getValue('GUEST_NET2_MAC')[0],
                                        'dstmac': S.getValue('GUEST_NET1_MAC')[0]})
            self._traffic['l3'].update({'srcip': S.getValue('VANILLA_TGEN_PORT1_IP'),
                                        'dstip': S.getValue('VANILLA_TGEN_PORT2_IP')})

        # Packet Forwarding mode
        self._vswitch_none = 'none' == S.getValue('VSWITCH').strip().lower()

    def run(self):
        """Run the test

        All setup and teardown through controllers is included.
        """
        self._logger.debug(self.name)

        # mount hugepages if needed
        self._mount_hugepages()

        # copy sources of l2 forwarding tools into VM shared dir if needed
        self._copy_fwd_tools_for_guest()

        self._logger.debug("Controllers:")
        loader = Loader()
        traffic_ctl = component_factory.create_traffic(
            self._traffic['traffic_type'],
            loader.get_trafficgen_class())
        vnf_ctl = component_factory.create_vnf(
            self.deployment,
            loader.get_vnf_class())

        if self._vswitch_none:
            vswitch_ctl = component_factory.create_pktfwd(
                loader.get_pktfwd_class())
        else:
            vswitch_ctl = component_factory.create_vswitch(
                self.deployment,
                loader.get_vswitch_class(),
                self._traffic)

        collector = component_factory.create_collector(
            loader.get_collector_class(),
            self._results_dir, self.name)
        loadgen = component_factory.create_loadgen(
            self._loadgen,
            self._load_cfg)

        self._logger.debug("Setup:")
        with vswitch_ctl, loadgen:
            with vnf_ctl, collector:
                if not self._vswitch_none:
                    self._add_flows(vswitch_ctl)

                with traffic_ctl:
                    traffic_ctl.send_traffic(self._traffic)

                # dump vswitch flows before they are affected by VNF termination
                if not self._vswitch_none:
                    vswitch_ctl.dump_vswitch_flows()

        # umount hugepages if mounted
        self._umount_hugepages()

        self._logger.debug("Traffic Results:")
        traffic_ctl.print_results()

        self._logger.debug("Collector Results:")
        collector.print_results()

        output_file = os.path.join(self._results_dir, "result_" + self.name +
                                   "_" + self.deployment + ".csv")

        tc_results = self._append_results(traffic_ctl.get_results())
        TestCase._write_result_to_file(tc_results, output_file)

        report.generate(output_file, tc_results, collector.get_results())

    def _append_results(self, results):
        """
        Method appends mandatory Test Case results to list of dictionaries.

        :param results: list of dictionaries which contains results from
                traffic generator.

        :returns: modified list of dictionaries.
        """
        for item in results:
            item[ResultsConstants.ID] = self.name
            item[ResultsConstants.DEPLOYMENT] = self.deployment
            item[ResultsConstants.TRAFFIC_TYPE] = self._traffic['l3']['proto']
            if self._traffic['multistream']:
                item[ResultsConstants.SCAL_STREAM_COUNT] = self._traffic['multistream']
                item[ResultsConstants.SCAL_STREAM_TYPE] = self._traffic['stream_type']
                item[ResultsConstants.SCAL_PRE_INSTALLED_FLOWS] = self._traffic['pre_installed_flows']
            if len(self.guest_loopback):
                item[ResultsConstants.GUEST_LOOPBACK] = ' '.join(self.guest_loopback)

        return results

    def _copy_fwd_tools_for_guest(self):
        """Copy dpdk and l2fwd code to GUEST_SHARE_DIR[s] for use by guests.
        """
        counter = 0
        # method is executed only for pvp and pvvp, so let's count number of 'v'
        while counter < self.deployment.count('v'):
            guest_dir = S.getValue('GUEST_SHARE_DIR')[counter]

            # create shared dir if it doesn't exist
            if not os.path.exists(guest_dir):
                os.makedirs(guest_dir)

            # copy sources into shared dir only if neccessary
            if 'testpmd' in self.guest_loopback or 'l2fwd' in self.guest_loopback:
                try:
                    tasks.run_task(['rsync', '-a', '-r', '-l', r'--exclude="\.git"',
                                    os.path.join(S.getValue('RTE_SDK'), ''),
                                    os.path.join(guest_dir, 'DPDK')],
                                   self._logger,
                                   'Copying DPDK to shared directory...',
                                   True)
                    tasks.run_task(['rsync', '-a', '-r', '-l',
                                    os.path.join(S.getValue('ROOT_DIR'), 'src/l2fwd/'),
                                    os.path.join(guest_dir, 'l2fwd')],
                                   self._logger,
                                   'Copying l2fwd to shared directory...',
                                   True)
                except subprocess.CalledProcessError:
                    self._logger.error('Unable to copy DPDK and l2fwd to shared directory')

            counter += 1

    def _mount_hugepages(self):
        """Mount hugepages if usage of DPDK or Qemu is detected
        """
        # hugepages are needed by DPDK and Qemu
        if not self._hugepages_mounted and \
            (self.deployment.count('v') or S.getValue('VSWITCH').lower().count('dpdk')):
            hugepages.mount_hugepages()
            self._hugepages_mounted = True

    def _umount_hugepages(self):
        """Umount hugepages if they were mounted before
        """
        if self._hugepages_mounted:
            hugepages.umount_hugepages()
            self._hugepages_mounted = False

    @staticmethod
    def _write_result_to_file(results, output):
        """Write list of dictionaries to a CSV file.

        Each element on list will create separate row in output file.
        If output file already exists, data will be appended at the end,
        otherwise it will be created.

        :param results: list of dictionaries.
        :param output: path to output file.
        """
        with open(output, 'a') as csvfile:

            logging.info("Write results to file: " + output)
            fieldnames = TestCase._get_unique_keys(results)

            writer = csv.DictWriter(csvfile, fieldnames)

            if not csvfile.tell():  # file is now empty
                writer.writeheader()

            for result in results:
                writer.writerow(result)


    @staticmethod
    def _get_unique_keys(list_of_dicts):
        """Gets unique key values as ordered list of strings in given dicts

        :param list_of_dicts: list of dictionaries.

        :returns: list of unique keys(strings).
        """
        result = OrderedDict()
        for item in list_of_dicts:
            for key in item.keys():
                result[key] = ''

        return list(result.keys())


    def _add_flows(vswitch_ctl):
        """Add flows to the vswitch

        :param vswitch_ctl vswitch controller
        """
        vswitch = vswitch_ctl.get_vswitch()
        # TODO BOM 15-08-07 the frame mod code assumes that the
        # physical ports are ports 1 & 2. The actual numbers
        # need to be retrived from the vSwitch and the metadata value
        # updated accordingly.
        bridge = S.getValue('VSWITCH_BRIDGE_NAME')
        if self._frame_mod == "vlan":
            # 0x8100 => VLAN ethertype
            self._logger.debug(" ****   VLAN   ***** ")
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['push_vlan:0x8100', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['push_vlan:0x8100', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "mpls":
            # 0x8847 => MPLS unicast ethertype
            self._logger.debug(" ****   MPLS  ***** ")
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['push_mpls:0x8847', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['push_mpls:0x8847', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "mac":
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['mod_dl_src:22:22:22:22:22:22',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['mod_dl_src:11:11:11:11:11:11',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "dscp":
            # DSCP 184d == 0x4E<<2 => 'Expedited Forwarding'
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_tos:184', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_tos:184', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ttl":
            # 251 and 241 are the highest prime numbers < 255
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_ttl:251', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_ttl:241', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ip_addr":
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_src:10.10.10.10',
                                'mod_nw_dst:20.20.20.20',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_src:20.20.20.20',
                                'mod_nw_dst:10.10.10.10',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ip_port":
            # TODO BOM 15-08-27 The traffic generated is assumed
            # to be UDP (nw_proto 17d) which is the default case but
            # we will need to pick up the actual traffic params in use.
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800', 'nw_proto':'17',
                    'actions': ['mod_tp_src:44444',
                                'mod_tp_dst:44444', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800', 'nw_proto':'17',
                    'actions': ['mod_tp_src:44444',
                                'mod_tp_dst:44444', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        else:
            pass