#!/usr/bin/env python
# Copyright 2016 Cisco Systems, Inc.  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.
#

import argparse
import copy
import datetime
import importlib
import json
import os
import sys
import traceback

from attrdict import AttrDict
import pbr.version
from pkg_resources import resource_string

from __init__ import __version__
from chain_runner import ChainRunner
from cleanup import Cleaner
from config import config_load
from config import config_loads
import credentials as credentials
from fluentd import FluentLogHandler
import log
from log import LOG
from nfvbenchd import WebServer
from specs import ChainType
from specs import Specs
from summarizer import NFVBenchSummarizer
import utils

fluent_logger = None


class NFVBench(object):
    """Main class of NFV benchmarking tool."""

    STATUS_OK = 'OK'
    STATUS_ERROR = 'ERROR'

    def __init__(self, config, openstack_spec, config_plugin, factory, notifier=None):
        # the base config never changes for a given NFVbench instance
        self.base_config = config
        # this is the running config, updated at every run()
        self.config = None
        self.config_plugin = config_plugin
        self.factory = factory
        self.notifier = notifier
        self.cred = credentials.Credentials(config.openrc_file, None, False) \
            if config.openrc_file else None
        self.chain_runner = None
        self.specs = Specs()
        self.specs.set_openstack_spec(openstack_spec)
        self.vni_ports = []
        sys.stdout.flush()

    def set_notifier(self, notifier):
        self.notifier = notifier

    def run(self, opts, args):
        """This run() method is called for every NFVbench benchmark request.

        In CLI mode, this method is called only once per invocation.
        In REST server mode, this is called once per REST POST request
        """
        status = NFVBench.STATUS_OK
        result = None
        message = ''
        if fluent_logger:
            # take a snapshot of the current time for this new run
            # so that all subsequent logs can relate to this run
            fluent_logger.start_new_run()
        LOG.info(args)
        try:
            # recalc the running config based on the base config and options for this run
            self._update_config(opts)
            if self.config.cache_size < 0:
                self.config.cache_size = self.config.flow_count
            # check that an empty openrc file (no OpenStack) is only allowed
            # with EXT chain
            if not self.config.openrc_file and self.config.service_chain != ChainType.EXT:
                raise Exception("openrc_file in the configuration is required for PVP/PVVP chains")

            self.specs.set_run_spec(self.config_plugin.get_run_spec(self.config,
                                                                    self.specs.openstack))
            self.chain_runner = ChainRunner(self.config,
                                            self.cred,
                                            self.specs,
                                            self.factory,
                                            self.notifier)
            new_frame_sizes = []
            # make sure that the min frame size is 64
            min_packet_size = 64
            for frame_size in self.config.frame_sizes:
                try:
                    if int(frame_size) < min_packet_size:
                        frame_size = str(min_packet_size)
                        LOG.info("Adjusting frame size %s bytes to minimum size %s bytes",
                                 frame_size, min_packet_size)
                    if frame_size not in new_frame_sizes:
                        new_frame_sizes.append(frame_size)
                except ValueError:
                    new_frame_sizes.append(frame_size.upper())
            self.config.frame_sizes = new_frame_sizes
            result = {
                "date": datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S'),
                "nfvbench_version": __version__,
                "config": self.config_plugin.prepare_results_config(copy.deepcopy(self.config)),
                "benchmarks": {
                    "network": {
                        "service_chain": self.chain_runner.run(),
                        "versions": self.chain_runner.get_version(),
                    }
                }
            }
            if self.specs.openstack:
                result['openstack_spec'] = {"vswitch": self.specs.openstack.vswitch,
                                            "encaps": self.specs.openstack.encaps}
            result['benchmarks']['network']['versions'].update(self.config_plugin.get_version())
        except Exception:
            status = NFVBench.STATUS_ERROR
            message = traceback.format_exc()
        except KeyboardInterrupt:
            status = NFVBench.STATUS_ERROR
            message = traceback.format_exc()
        finally:
            if self.chain_runner:
                self.chain_runner.close()

        if status == NFVBench.STATUS_OK:
            # result2 = utils.dict_to_json_dict(result)
            return {
                'status': status,
                'result': result
            }
        return {
            'status': status,
            'error_message': message
        }

    def prepare_summary(self, result):
        """Prepare summary of the result to print and send it to logger (eg: fluentd)."""
        global fluent_logger
        summary = NFVBenchSummarizer(result, fluent_logger)
        LOG.info(str(summary))

    def save(self, result):
        """Save results in json format file."""
        utils.save_json_result(result,
                               self.config.json_file,
                               self.config.std_json_path,
                               self.config.service_chain,
                               self.config.service_chain_count,
                               self.config.flow_count,
                               self.config.frame_sizes)

    def _update_config(self, opts):
        """Recalculate the running config based on the base config and opts.

        Sanity check on the config is done here as well.
        """
        self.config = AttrDict(dict(self.base_config))
        self.config.update(opts)
        config = self.config

        config.service_chain = config.service_chain.upper()
        config.service_chain_count = int(config.service_chain_count)
        if config.l2_loopback:
            # force the number of chains to be 1 in case of l2 loopback
            config.service_chain_count = 1
            config.service_chain = ChainType.EXT
            config.no_arp = True
            LOG.info('Running L2 loopback: using EXT chain/no ARP')
        config.flow_count = utils.parse_flow_count(config.flow_count)
        required_flow_count = config.service_chain_count * 2
        if config.flow_count < required_flow_count:
            LOG.info("Flow count %d has been set to minimum value of '%d' "
                     "for current configuration", config.flow_count,
                     required_flow_count)
            config.flow_count = required_flow_count

        if config.flow_count % 2:
            config.flow_count += 1

        config.duration_sec = float(config.duration_sec)
        config.interval_sec = float(config.interval_sec)
        config.pause_sec = float(config.pause_sec)

        if config.traffic is None or not config.traffic:
            raise Exception("Missing traffic property in configuration")

        if config.openrc_file:
            config.openrc_file = os.path.expanduser(config.openrc_file)
            if config.flavor.vcpus < 2:
                raise Exception("Flavor vcpus must be >= 2")


        config.ndr_run = (not config.no_traffic and
                          'ndr' in config.rate.strip().lower().split('_'))
        config.pdr_run = (not config.no_traffic and
                          'pdr' in config.rate.strip().lower().split('_'))
        config.single_run = (not config.no_traffic and
                             not (config.ndr_run or config.pdr_run))

        config.json_file = config.json if config.json else None
        if config.json_file:
            (path, _filename) = os.path.split(config.json)
            if not os.path.exists(path):
                raise Exception('Please provide existing path for storing results in JSON file. '
                                'Path used: {path}'.format(path=path))

        config.std_json_path = config.std_json if config.std_json else None
        if config.std_json_path:
            if not os.path.exists(config.std_json):
                raise Exception('Please provide existing path for storing results in JSON file. '
                                'Path used: {path}'.format(path=config.std_json_path))

        # Check that multiqueue is between 1 and 8 (8 is the max allowed by libvirt/qemu)
        if config.vif_multiqueue_size < 1 or config.vif_multiqueue_size > 8:
            raise Exception('vif_multiqueue_size (%d) must be in [1..8]' %
                            config.vif_multiqueue_size)

        # VxLAN sanity checks
        if config.vxlan:
            if config.vlan_tagging:
                config.vlan_tagging = False
                LOG.info('VxLAN: vlan_tagging forced to False '
                         '(inner VLAN tagging must be disabled)')

        self.config_plugin.validate_config(config, self.specs.openstack)


def _parse_opts_from_cli():
    parser = argparse.ArgumentParser()

    parser.add_argument('--status', dest='status',
                        action='store_true',
                        default=None,
                        help='Provide NFVbench status')

    parser.add_argument('-c', '--config', dest='config',
                        action='store',
                        help='Override default values with a config file or '
                             'a yaml/json config string',
                        metavar='<file_name_or_yaml>')

    parser.add_argument('--server', dest='server',
                        default=None,
                        action='store_true',
                        help='Run nfvbench in server mode')

    parser.add_argument('--host', dest='host',
                        action='store',
                        default='0.0.0.0',
                        help='Host IP address on which server will be listening (default 0.0.0.0)')

    parser.add_argument('-p', '--port', dest='port',
                        action='store',
                        default=7555,
                        help='Port on which server will be listening (default 7555)')

    parser.add_argument('-sc', '--service-chain', dest='service_chain',
                        choices=ChainType.names,
                        action='store',
                        help='Service chain to run')

    parser.add_argument('-scc', '--service-chain-count', dest='service_chain_count',
                        action='store',
                        help='Set number of service chains to run',
                        metavar='<service_chain_count>')

    parser.add_argument('-fc', '--flow-count', dest='flow_count',
                        action='store',
                        help='Set number of total flows for all chains and all directions',
                        metavar='<flow_count>')

    parser.add_argument('--rate', dest='rate',
                        action='store',
                        help='Specify rate in pps, bps or %% as total for all directions',
                        metavar='<rate>')

    parser.add_argument('--duration', dest='duration_sec',
                        action='store',
                        help='Set duration to run traffic generator (in seconds)',
                        metavar='<duration_sec>')

    parser.add_argument('--interval', dest='interval_sec',
                        action='store',
                        help='Set interval to record traffic generator stats (in seconds)',
                        metavar='<interval_sec>')

    parser.add_argument('--inter-node', dest='inter_node',
                        default=None,
                        action='store_true',
                        help='(deprecated)')

    parser.add_argument('--sriov', dest='sriov',
                        default=None,
                        action='store_true',
                        help='Use SRIOV (no vswitch - requires SRIOV support in compute nodes)')

    parser.add_argument('--use-sriov-middle-net', dest='use_sriov_middle_net',
                        default=None,
                        action='store_true',
                        help='Use SRIOV to handle the middle network traffic '
                             '(PVVP with SRIOV only)')

    parser.add_argument('-d', '--debug', dest='debug',
                        action='store_true',
                        default=None,
                        help='print debug messages (verbose)')

    parser.add_argument('-g', '--traffic-gen', dest='generator_profile',
                        action='store',
                        help='Traffic generator profile to use')

    parser.add_argument('-l3', '--l3-router', dest='l3_router',
                        default=None,
                        action='store_true',
                        help='Use L3 neutron routers to handle traffic')

    parser.add_argument('-0', '--no-traffic', dest='no_traffic',
                        default=None,
                        action='store_true',
                        help='Check config and connectivity only - do not generate traffic')

    parser.add_argument('--no-arp', dest='no_arp',
                        default=None,
                        action='store_true',
                        help='Do not use ARP to find MAC addresses, '
                             'instead use values in config file')

    parser.add_argument('--no-vswitch-access', dest='no_vswitch_access',
                        default=None,
                        action='store_true',
                        help='Skip vswitch configuration and retrieving of stats')

    parser.add_argument('--vxlan', dest='vxlan',
                        default=None,
                        action='store_true',
                        help='Enable VxLan encapsulation')

    parser.add_argument('--no-cleanup', dest='no_cleanup',
                        default=None,
                        action='store_true',
                        help='no cleanup after run')

    parser.add_argument('--cleanup', dest='cleanup',
                        default=None,
                        action='store_true',
                        help='Cleanup NFVbench resources (prompt to confirm)')

    parser.add_argument('--force-cleanup', dest='force_cleanup',
                        default=None,
                        action='store_true',
                        help='Cleanup NFVbench resources (do not prompt)')

    parser.add_argument('--restart', dest='restart',
                        default=None,
                        action='store_true',
                        help='Restart TRex server')

    parser.add_argument('--json', dest='json',
                        action='store',
                        help='store results in json format file',
                        metavar='<path>/<filename>')

    parser.add_argument('--std-json', dest='std_json',
                        action='store',
                        help='store results in json format file with nfvbench standard filename: '
                             '<service-chain-type>-<service-chain-count>-<flow-count>'
                             '-<packet-sizes>.json',
                        metavar='<path>')

    parser.add_argument('--show-default-config', dest='show_default_config',
                        default=None,
                        action='store_true',
                        help='print the default config in yaml format (unedited)')

    parser.add_argument('--show-config', dest='show_config',
                        default=None,
                        action='store_true',
                        help='print the running config in json format')

    parser.add_argument('-ss', '--show-summary', dest='summary',
                        action='store',
                        help='Show summary from nfvbench json file',
                        metavar='<json>')

    parser.add_argument('-v', '--version', dest='version',
                        default=None,
                        action='store_true',
                        help='Show version')

    parser.add_argument('-fs', '--frame-size', dest='frame_sizes',
                        action='append',
                        help='Override traffic profile frame sizes',
                        metavar='<frame_size_bytes or IMIX>')

    parser.add_argument('--unidir', dest='unidir',
                        action='store_true',
                        default=None,
                        help='Override traffic profile direction (requires -fs)')

    parser.add_argument('--log-file', '--logfile', dest='log_file',
                        action='store',
                        help='Filename for saving logs',
                        metavar='<log_file>')

    parser.add_argument('--user-label', '--userlabel', dest='user_label',
                        action='store',
                        help='Custom label for performance records')

    parser.add_argument('--hypervisor', dest='hypervisor',
                        action='store',
                        metavar='<hypervisor name>',
                        help='Where chains must run ("compute", "az:", "az:compute")')

    parser.add_argument('--l2-loopback', '--l2loopback', dest='l2_loopback',
                        action='store',
                        metavar='<vlan>',
                        help='Port to port or port to switch to port L2 loopback with VLAN id')

    parser.add_argument('--cache-size', dest='cache_size',
                        action='store',
                        default='0',
                        help='Specify the FE cache size (default: 0, flow-count if < 0)')

    parser.add_argument('--service-mode', dest='service_mode',
                        action='store_true',
                        default=False,
                        help='Enable T-Rex service mode for debugging only')

    parser.add_argument('--no-flow-stats', dest='no_flow_stats',
                        action='store_true',
                        default=False,
                        help='Disable extra flow stats (on high load traffic)')

    parser.add_argument('--no-latency-stats', dest='no_latency_stats',
                        action='store_true',
                        default=False,
                        help='Disable flow stats for latency traffic')

    parser.add_argument('--no-latency-streams', dest='no_latency_streams',
                        action='store_true',
                        default=False,
                        help='Disable latency measurements (no streams)')

    opts, unknown_opts = parser.parse_known_args()
    return opts, unknown_opts


def load_default_config():
    default_cfg = resource_string(__name__, "cfg.default.yaml")
    config = config_loads(default_cfg)
    config.name = '(built-in default config)'
    return config, default_cfg


def override_custom_traffic(config, frame_sizes, unidir):
    """Override the traffic profiles with a custom one."""
    if frame_sizes is not None:
        traffic_profile_name = "custom_traffic_profile"
        config.traffic_profile = [
            {
                "l2frame_size": frame_sizes,
                "name": traffic_profile_name
            }
        ]
    else:
        traffic_profile_name = config.traffic["profile"]

    bidirectional = config.traffic['bidirectional'] if unidir is None else not unidir
    config.traffic = {
        "bidirectional": bidirectional,
        "profile": traffic_profile_name
    }


def check_physnet(name, netattrs):
    if not netattrs.physical_network:
        raise Exception("SRIOV requires physical_network to be specified for the {n} network"
                        .format(n=name))
    if not netattrs.segmentation_id:
        raise Exception("SRIOV requires segmentation_id to be specified for the {n} network"
                        .format(n=name))

def status_cleanup(config, cleanup, force_cleanup):
    LOG.info('Version: %s', pbr.version.VersionInfo('nfvbench').version_string_with_vcs())
    # check if another run is pending
    ret_code = 0
    try:
        with utils.RunLock():
            LOG.info('Status: idle')
    except Exception:
        LOG.info('Status: busy (run pending)')
        ret_code = 1
    # check nfvbench resources
    if config.openrc_file and config.service_chain != ChainType.EXT:
        cleaner = Cleaner(config)
        count = cleaner.show_resources()
        if count and (cleanup or force_cleanup):
            cleaner.clean(not force_cleanup)
    sys.exit(ret_code)

def main():
    global fluent_logger
    run_summary_required = False
    try:
        log.setup()
        # load default config file
        config, default_cfg = load_default_config()
        # create factory for platform specific classes
        try:
            factory_module = importlib.import_module(config['factory_module'])
            factory = getattr(factory_module, config['factory_class'])()
        except AttributeError:
            raise Exception("Requested factory module '{m}' or class '{c}' was not found."
                            .format(m=config['factory_module'], c=config['factory_class']))
        # create config plugin for this platform
        config_plugin = factory.get_config_plugin_class()(config)
        config = config_plugin.get_config()

        opts, unknown_opts = _parse_opts_from_cli()
        log.set_level(debug=opts.debug)

        if opts.version:
            print pbr.version.VersionInfo('nfvbench').version_string_with_vcs()
            sys.exit(0)

        if opts.summary:
            with open(opts.summary) as json_data:
                result = json.load(json_data)
                if opts.user_label:
                    result['config']['user_label'] = opts.user_label
                print NFVBenchSummarizer(result, fluent_logger)
            sys.exit(0)

        # show default config in text/yaml format
        if opts.show_default_config:
            print default_cfg
            sys.exit(0)

        config.name = ''
        if opts.config:
            # do not check extra_specs in flavor as it can contain any key/value pairs
            whitelist_keys = ['extra_specs']
            # override default config options with start config at path parsed from CLI
            # check if it is an inline yaml/json config or a file name
            if os.path.isfile(opts.config):
                LOG.info('Loading configuration file: %s', opts.config)
                config = config_load(opts.config, config, whitelist_keys)
                config.name = os.path.basename(opts.config)
            else:
                LOG.info('Loading configuration string: %s', opts.config)
                config = config_loads(opts.config, config, whitelist_keys)

        # setup the fluent logger as soon as possible right after the config plugin is called,
        # if there is any logging or result tag is set then initialize the fluent logger
        for fluentd in config.fluentd:
            if fluentd.logging_tag or fluentd.result_tag:
                fluent_logger = FluentLogHandler(config.fluentd)
                LOG.addHandler(fluent_logger)
                break

        # traffic profile override options
        override_custom_traffic(config, opts.frame_sizes, opts.unidir)

        # copy over cli options that are used in config
        config.generator_profile = opts.generator_profile
        if opts.sriov:
            config.sriov = True
        if opts.log_file:
            config.log_file = opts.log_file
        if opts.service_chain:
            config.service_chain = opts.service_chain
        if opts.service_chain_count:
            config.service_chain_count = opts.service_chain_count
        if opts.no_vswitch_access:
            config.no_vswitch_access = opts.no_vswitch_access
        if opts.hypervisor:
            # can be any of 'comp1', 'nova:', 'nova:comp1'
            config.compute_nodes = opts.hypervisor
        if opts.vxlan:
            config.vxlan = True
        if opts.restart:
            config.restart = True
        if opts.service_mode:
            config.service_mode = True
        if opts.no_flow_stats:
            config.no_flow_stats = True
        if opts.no_latency_stats:
            config.no_latency_stats = True
        if opts.no_latency_streams:
            config.no_latency_streams = True
        # port to port loopback (direct or through switch)
        if opts.l2_loopback:
            config.l2_loopback = True
            if config.service_chain != ChainType.EXT:
                LOG.info('Changing service chain type to EXT')
                config.service_chain = ChainType.EXT
            if not config.no_arp:
                LOG.info('Disabling ARP')
                config.no_arp = True
            config.vlans = [int(opts.l2_loopback), int(opts.l2_loopback)]
            LOG.info('Running L2 loopback: using EXT chain/no ARP')

        if opts.use_sriov_middle_net:
            if (not config.sriov) or (config.service_chain != ChainType.PVVP):
                raise Exception("--use-sriov-middle-net is only valid for PVVP with SRIOV")
            config.use_sriov_middle_net = True

        if config.sriov and config.service_chain != ChainType.EXT:
            # if sriov is requested (does not apply to ext chains)
            # make sure the physnet names are specified
            check_physnet("left", config.internal_networks.left)
            check_physnet("right", config.internal_networks.right)
            if config.service_chain == ChainType.PVVP and config.use_sriov_middle_net:
                check_physnet("middle", config.internal_networks.middle)

        # show running config in json format
        if opts.show_config:
            print json.dumps(config, sort_keys=True, indent=4)
            sys.exit(0)

        # update the config in the config plugin as it might have changed
        # in a copy of the dict (config plugin still holds the original dict)
        config_plugin.set_config(config)

        if opts.status or opts.cleanup or opts.force_cleanup:
            status_cleanup(config, opts.cleanup, opts.force_cleanup)

        # add file log if requested
        if config.log_file:
            log.add_file_logger(config.log_file)

        openstack_spec = config_plugin.get_openstack_spec() if config.openrc_file \
            else None

        nfvbench_instance = NFVBench(config, openstack_spec, config_plugin, factory)

        if opts.server:
            server = WebServer(nfvbench_instance, fluent_logger)
            try:
                port = int(opts.port)
            except ValueError:
                server.run(host=opts.host)
            else:
                server.run(host=opts.host, port=port)
            # server.run() should never return
        else:
            with utils.RunLock():
                run_summary_required = True
                if unknown_opts:
                    err_msg = 'Unknown options: ' + ' '.join(unknown_opts)
                    LOG.error(err_msg)
                    raise Exception(err_msg)

                # remove unfilled values
                opts = {k: v for k, v in vars(opts).iteritems() if v is not None}
                # get CLI args
                params = ' '.join(str(e) for e in sys.argv[1:])
                result = nfvbench_instance.run(opts, params)
                if 'error_message' in result:
                    raise Exception(result['error_message'])

                if 'result' in result and result['status']:
                    nfvbench_instance.save(result['result'])
                    nfvbench_instance.prepare_summary(result['result'])
    except Exception as exc:
        run_summary_required = True
        LOG.error({
            'status': NFVBench.STATUS_ERROR,
            'error_message': traceback.format_exc()
        })
        print str(exc)
    finally:
        if fluent_logger:
            # only send a summary record if there was an actual nfvbench run or
            # if an error/exception was logged.
            fluent_logger.send_run_summary(run_summary_required)


if __name__ == '__main__':
    main()