"""
Copyright 2021 Open Networking Foundation (ONF)

Please refer questions to either the onos test mailing list at <onos-test@onosproject.org>,
the System Testing Plans and Results wiki page at <https://wiki.onosproject.org/x/voMg>,
or the System Testing Guide page at <https://wiki.onosproject.org/x/WYQg>

"""
import time
import os
import sys
import importlib
import collections
import numpy as np

from drivers.common.api.controllerdriver import Controller

from socket import error as ConnectionRefusedError
from distutils.util import strtobool

TREX_FILES_DIR = "/tmp/trex_files/"

LatencyStats = collections.namedtuple(
    "LatencyStats",
    [
        "pg_id",
        "jitter",
        "average",
        "total_max",
        "total_min",
        "last_max",
        "histogram",
        "dropped",
        "out_of_order",
        "duplicate",
        "seq_too_high",
        "seq_too_low",
        "percentile_50",
        "percentile_75",
        "percentile_90",
        "percentile_99",
        "percentile_99_9",
        "percentile_99_99",
        "percentile_99_999",
    ],
)

PortStats = collections.namedtuple(
    "PortStats",
    [
        "tx_packets",
        "rx_packets",
        "tx_bytes",
        "rx_bytes",
        "tx_errors",
        "rx_errors",
        "tx_bps",
        "tx_pps",
        "tx_bps_L1",
        "tx_util",
        "rx_bps",
        "rx_pps",
        "rx_bps_L1",
        "rx_util",
    ],
)

FlowStats = collections.namedtuple(
    "FlowStats",
    [
        "pg_id",
        "tx_packets",
        "rx_packets",
        "tx_bytes",
        "rx_bytes",
    ],
)


class TrexClientDriver(Controller):
    """
    Implements a Trex Client Driver
    """

    def __init__(self):
        self.trex_address = "localhost"
        self.trex_config = None  # Relative path in dependencies of the test using this driver
        self.force_restart = True
        self.sofware_mode = False
        self.setup_successful = False
        self.stats = None
        self.trex_client = None
        self.trex_daemon_client = None
        self.trex_library_python_path = None
        super(TrexClientDriver, self).__init__()

    def connect(self, **connectargs):
        global STLClient, STLStreamDstMAC_PKT, CTRexClient, STLPktBuilder, \
            STLFlowLatencyStats, STLStream, STLTXCont
        try:
            for key in connectargs:
                vars(self)[key] = connectargs[key]
            for key in self.options:
                if key == "trex_address":
                    self.trex_address = self.options[key]
                elif key == "trex_config":
                    self.trex_config = self.options[key]
                elif key == "force_restart":
                    self.force_restart = bool(strtobool(self.options[key]))
                elif key == "software_mode":
                    self.software_mode = bool(strtobool(self.options[key]))
                elif key == "trex_library_python_path":
                    self.trex_library_python_path = self.options[key]
            self.name = self.options["name"]
            if self.trex_library_python_path is not None:
                sys.path.append(self.trex_library_python_path)
            # Import after appending the TRex library Python path
            STLClient = getattr(importlib.import_module("trex.stl.api"), "STLClient")
            STLStreamDstMAC_PKT = getattr(importlib.import_module("trex.stl.api"), "STLStreamDstMAC_PKT")
            CTRexClient = getattr(importlib.import_module("trex_stf_lib.trex_client"), "CTRexClient")
            STLFlowLatencyStats = getattr(importlib.import_module("trex_stl_lib.api"), "STLFlowLatencyStats")
            STLPktBuilder = getattr(importlib.import_module("trex_stl_lib.api"), "STLPktBuilder")
            STLStream = getattr(importlib.import_module("trex_stl_lib.api"), "STLStream")
            STLTXCont = getattr(importlib.import_module("trex_stl_lib.api"), "STLTXCont")
        except Exception as inst:
            main.log.error("Uncaught exception: " + str(inst))
            main.cleanAndExit()
        return super(TrexClientDriver, self).connect()

    def disconnect(self):
        """
        Called when Test is complete
        """
        self.disconnectTrexClient()
        self.stopTrexServer()
        return main.TRUE

    def setupTrex(self, pathToTrexConfig):
        """
        Setup TRex server passing the TRex configuration.
        :return: True if setup successful, False otherwise
        """
        main.log.debug(self.name + ": Setting up TRex server")
        if self.software_mode:
            trex_args = "--software --no-hw-flow-stat"
        else:
            trex_args = None
        self.trex_daemon_client = CTRexClient(self.trex_address,
                                              trex_args=trex_args)
        success = self.__set_up_trex_server(
            self.trex_daemon_client, self.trex_address,
            os.path.join(pathToTrexConfig, self.trex_config),
            self.force_restart
        )
        if not success:
            main.log.error("Failed to set up TRex daemon!")
            return False
        self.setup_successful = True
        return True

    def connectTrexClient(self):
        if not self.setup_successful:
            main.log.error("Cannot connect TRex Client, first setup TRex")
            return False
        main.log.info("Connecting TRex Client")
        self.trex_client = STLClient(server=self.trex_address)
        self.trex_client.connect()
        self.trex_client.acquire()
        self.trex_client.reset()  # Resets configs from all ports
        self.trex_client.clear_stats()  # Clear status from all ports
        # Put all ports to promiscuous mode, otherwise they will drop all
        # incoming packets if the destination mac is not the port mac address.
        self.trex_client.set_port_attr(self.trex_client.get_all_ports(),
                                       promiscuous=True)
        # Reset the used sender ports
        self.all_sender_port = set()
        self.stats = None
        return True

    def disconnectTrexClient(self):
        # Teardown TREX Client
        if self.trex_client is not None:
            main.log.info("Tearing down STLClient...")
            self.trex_client.stop()
            self.trex_client.release()
            self.trex_client.disconnect()
            self.trex_client = None
            # Do not reset stats

    def stopTrexServer(self):
        if self.trex_daemon_client is not None:
            self.trex_daemon_client.stop_trex()
            self.trex_daemon_client = None

    def addStream(self, pkt, trex_port, l1_bps=None, percentage=None,
                  delay=0, flow_id=None, flow_stats=False):
        """
        :param pkt: Scapy packet, TRex will send copy of this packet
        :param trex_port: Port number to send packet from, must match a port in the TRex config file
        :param l1_bps: L1 Throughput generated by TRex (mutually exclusive with percentage)
        :param percentage: Percentage usage of the selected port bandwidth (mutually exlusive with l1_bps)
        :param flow_id: Flow ID, required when saving latency statistics
        :param flow_stats: True to measure flow statistics (latency and packet), False otherwise, might require software mode
        :return: True if the stream is create, false otherwise
        """
        if (percentage is None and l1_bps is None) or (
                percentage is not None and l1_bps is not None):
            main.log.error(
                "Either percentage or l1_bps must be provided when creating a stream")
            return False
        main.log.debug("Creating flow stream")
        main.log.debug(
            "port: %d, l1_bps: %s, percentage: %s, delay: %d, flow_id:%s, flow_stats: %s" % (
                trex_port, str(l1_bps), str(percentage), delay, str(flow_id),
                str(flow_stats)))
        main.log.debug(pkt.summary())
        if flow_stats:
            traffic_stream = self.__create_latency_stats_stream(
                pkt,
                pg_id=flow_id,
                isg=delay,
                percentage=percentage,
                l1_bps=l1_bps)
        else:
            traffic_stream = self.__create_background_stream(
                pkt,
                percentage=percentage,
                l1_bps=l1_bps)
        self.trex_client.add_streams(traffic_stream, ports=trex_port)
        self.all_sender_port.add(trex_port)
        return True

    def startAndWaitTraffic(self, duration=10):
        """
        Start generating traffic and wait traffic to be send
        :param duration: Traffic generation duration
        :return:
        """
        if not self.trex_client:
            main.log.error(
                "Cannot start traffic, first connect the TRex client")
            return False
        main.log.info("Start sending traffic for %d seconds" % duration)
        self.trex_client.start(list(self.all_sender_port), mult="1",
                               duration=duration)
        main.log.info("Waiting until all traffic is sent..")
        self.trex_client.wait_on_traffic(ports=list(self.all_sender_port),
                                         rx_delay_ms=100)
        main.log.info("...traffic sent!")
        # Reset sender port so we can run other tests with the same TRex client
        self.all_sender_port = set()
        main.log.info("Getting stats")
        self.stats = self.trex_client.get_stats()
        main.log.info("GOT stats")

    def getFlowStats(self, flow_id):
        if self.stats is None:
            main.log.error("No stats saved!")
            return None
        return TrexClientDriver.__get_flow_stats(flow_id, self.stats)

    def logFlowStats(self, flow_id):
        main.log.info("Statistics for flow {}: {}".format(
            flow_id,
            TrexClientDriver.__get_readable_flow_stats(
                self.getFlowStats(flow_id))))

    def getLatencyStats(self, flow_id):
        if self.stats is None:
            main.log.error("No stats saved!")
            return None
        return TrexClientDriver.__get_latency_stats(flow_id, self.stats)

    def logLatencyStats(self, flow_id):
        main.log.info("Latency statistics for flow {}: {}".format(
            flow_id,
            TrexClientDriver.__get_readable_latency_stats(
                self.getLatencyStats(flow_id))))

    def getPortStats(self, port_id):
        if self.stats is None:
            main.log.error("No stats saved!")
            return None
        return TrexClientDriver.__get_port_stats(port_id, self.stats)

    def logPortStats(self, port_id):
        if self.stats is None:
            main.log.error("No stats saved!")
            return None
        main.log.info("Statistics for port {}: {}".format(
            port_id, TrexClientDriver.__get_readable_port_stats(
                self.stats.get(port_id))))

    # From ptf/test/common/ptf_runner.py
    def __set_up_trex_server(self, trex_daemon_client, trex_address,
                             trex_config,
                             force_restart):
        try:
            main.log.info("Pushing Trex config %s to the server" % trex_config)
            if not trex_daemon_client.push_files(trex_config):
                main.log.error("Unable to push %s to Trex server" % trex_config)
                return False

            if force_restart:
                main.log.info("Restarting TRex")
                trex_daemon_client.kill_all_trexes()
                time.sleep(1)

            if not trex_daemon_client.is_idle():
                main.log.info("The Trex server process is running")
                main.log.warn(
                    "A Trex server process is still running, "
                    + "use --force-restart to kill it if necessary."
                )
                return False

            trex_config_file_on_server = TREX_FILES_DIR + os.path.basename(
                trex_config)
            trex_daemon_client.start_stateless(cfg=trex_config_file_on_server)
        except ConnectionRefusedError:
            main.log.error(
                "Unable to connect to server %s.\n" + "Did you start the Trex daemon?" % trex_address)
            return False

        return True

    def __create_latency_stats_stream(self, pkt, pg_id,
                                      name=None,
                                      l1_bps=None,
                                      percentage=None,
                                      isg=0):
        assert (percentage is None and l1_bps is not None) or (
                percentage is not None and l1_bps is None)
        return STLStream(
            name=name,
            packet=STLPktBuilder(pkt=pkt),
            mode=STLTXCont(bps_L1=l1_bps, percentage=percentage),
            isg=isg,
            flow_stats=STLFlowLatencyStats(pg_id=pg_id)
        )

    def __create_background_stream(self, pkt, name=None, percentage=None,
                                   l1_bps=None):
        assert (percentage is None and l1_bps is not None) or (
                percentage is not None and l1_bps is None)
        return STLStream(
            name=name,
            packet=STLPktBuilder(pkt=pkt),
            mode=STLTXCont(bps_L1=l1_bps, percentage=percentage)
        )

    # Multiplier for data rates
    K = 1000
    M = 1000 * K
    G = 1000 * M

    @staticmethod
    def __to_readable(src, unit="bps"):
        """
        Convert number to human readable string.
        For example: 1,000,000 bps to 1Mbps. 1,000 bytes to 1KB

        :parameters:
            src : int
                the original data
            unit : str
                the unit ('bps', 'pps', or 'bytes')
        :returns:
            A human readable string
        """
        if src < 1000:
            return "{:.1f} {}".format(src, unit)
        elif src < 1000000:
            return "{:.1f} K{}".format(src / 1000, unit)
        elif src < 1000000000:
            return "{:.1f} M{}".format(src / 1000000, unit)
        else:
            return "{:.1f} G{}".format(src / 1000000000, unit)

    @staticmethod
    def __get_readable_port_stats(port_stats):
        opackets = port_stats.get("opackets", 0)
        ipackets = port_stats.get("ipackets", 0)
        obytes = port_stats.get("obytes", 0)
        ibytes = port_stats.get("ibytes", 0)
        oerrors = port_stats.get("oerrors", 0)
        ierrors = port_stats.get("ierrors", 0)
        tx_bps = port_stats.get("tx_bps", 0)
        tx_pps = port_stats.get("tx_pps", 0)
        tx_bps_L1 = port_stats.get("tx_bps_L1", 0)
        tx_util = port_stats.get("tx_util", 0)
        rx_bps = port_stats.get("rx_bps", 0)
        rx_pps = port_stats.get("rx_pps", 0)
        rx_bps_L1 = port_stats.get("rx_bps_L1", 0)
        rx_util = port_stats.get("rx_util", 0)
        return """
        Output packets: {}
        Input packets: {}
        Output bytes: {} ({})
        Input bytes: {} ({})
        Output errors: {}
        Input errors: {}
        TX bps: {} ({})
        TX pps: {} ({})
        L1 TX bps: {} ({})
        TX util: {}
        RX bps: {} ({})
        RX pps: {} ({})
        L1 RX bps: {} ({})
        RX util: {}""".format(
            opackets,
            ipackets,
            obytes,
            TrexClientDriver.__to_readable(obytes, "Bytes"),
            ibytes,
            TrexClientDriver.__to_readable(ibytes, "Bytes"),
            oerrors,
            ierrors,
            tx_bps,
            TrexClientDriver.__to_readable(tx_bps),
            tx_pps,
            TrexClientDriver.__to_readable(tx_pps, "pps"),
            tx_bps_L1,
            TrexClientDriver.__to_readable(tx_bps_L1),
            tx_util,
            rx_bps,
            TrexClientDriver.__to_readable(rx_bps),
            rx_pps,
            TrexClientDriver.__to_readable(rx_pps, "pps"),
            rx_bps_L1,
            TrexClientDriver.__to_readable(rx_bps_L1),
            rx_util,
        )

    @staticmethod
    def __get_port_stats(port, stats):
        """
        :param port: int
        :param stats:
        :return:
        """
        port_stats = stats.get(port)
        return PortStats(
            tx_packets=port_stats.get("opackets", 0),
            rx_packets=port_stats.get("ipackets", 0),
            tx_bytes=port_stats.get("obytes", 0),
            rx_bytes=port_stats.get("ibytes", 0),
            tx_errors=port_stats.get("oerrors", 0),
            rx_errors=port_stats.get("ierrors", 0),
            tx_bps=port_stats.get("tx_bps", 0),
            tx_pps=port_stats.get("tx_pps", 0),
            tx_bps_L1=port_stats.get("tx_bps_L1", 0),
            tx_util=port_stats.get("tx_util", 0),
            rx_bps=port_stats.get("rx_bps", 0),
            rx_pps=port_stats.get("rx_pps", 0),
            rx_bps_L1=port_stats.get("rx_bps_L1", 0),
            rx_util=port_stats.get("rx_util", 0),
        )

    @staticmethod
    def __get_latency_stats(pg_id, stats):
        """
        :param pg_id: int
        :param stats:
        :return:
        """

        lat_stats = stats["latency"].get(pg_id)
        lat = lat_stats["latency"]
        # Estimate latency percentiles from the histogram.
        l = list(lat["histogram"].keys())
        l.sort()
        all_latencies = []
        for sample in l:
            range_start = sample
            if range_start == 0:
                range_end = 10
            else:
                range_end = range_start + pow(10, (len(str(range_start)) - 1))
            val = lat["histogram"][sample]
            # Assume whole the bucket experienced the range_end latency.
            all_latencies += [range_end] * val
        q = [50, 75, 90, 99, 99.9, 99.99, 99.999]
        percentiles = np.percentile(all_latencies, q)

        ret = LatencyStats(
            pg_id=pg_id,
            jitter=lat["jitter"],
            average=lat["average"],
            total_max=lat["total_max"],
            total_min=lat["total_min"],
            last_max=lat["last_max"],
            histogram=lat["histogram"],
            dropped=lat_stats["err_cntrs"]["dropped"],
            out_of_order=lat_stats["err_cntrs"]["out_of_order"],
            duplicate=lat_stats["err_cntrs"]["dup"],
            seq_too_high=lat_stats["err_cntrs"]["seq_too_high"],
            seq_too_low=lat_stats["err_cntrs"]["seq_too_low"],
            percentile_50=percentiles[0],
            percentile_75=percentiles[1],
            percentile_90=percentiles[2],
            percentile_99=percentiles[3],
            percentile_99_9=percentiles[4],
            percentile_99_99=percentiles[5],
            percentile_99_999=percentiles[6],
        )
        return ret

    @staticmethod
    def __get_readable_latency_stats(stats):
        """
        :param stats: LatencyStats
        :return:
        """
        histogram = ""
        # need to listify in order to be able to sort them.
        l = list(stats.histogram.keys())
        l.sort()
        for sample in l:
            range_start = sample
            if range_start == 0:
                range_end = 10
            else:
                range_end = range_start + pow(10, (len(str(range_start)) - 1))
            val = stats.histogram[sample]
            histogram = (
                    histogram
                    + "\n        Packets with latency between {0:>5} us and {1:>5} us: {2:>10}".format(
                range_start, range_end, val
            )
            )

        return """
        Latency info for pg_id {}
        Dropped packets: {}
        Out-of-order packets: {}
        Sequence too high packets: {}
        Sequence too low packets: {}
        Maximum latency: {} us
        Minimum latency: {} us
        Maximum latency in last sampling period: {} us
        Average latency: {} us
        50th percentile latency: {} us
        75th percentile latency: {} us
        90th percentile latency: {} us
        99th percentile latency: {} us
        99.9th percentile latency: {} us
        99.99th percentile latency: {} us
        99.999th percentile latency: {} us
        Jitter: {} us
        Latency distribution histogram: {}
        """.format(stats.pg_id, stats.dropped, stats.out_of_order,
                   stats.seq_too_high, stats.seq_too_low, stats.total_max,
                   stats.total_min, stats.last_max, stats.average,
                   stats.percentile_50, stats.percentile_75,
                   stats.percentile_90,
                   stats.percentile_99, stats.percentile_99_9,
                   stats.percentile_99_99,
                   stats.percentile_99_999, stats.jitter, histogram)

    @staticmethod
    def __get_flow_stats(pg_id, stats):
        """
        :param pg_id: int
        :param stats:
        :return:
        """
        FlowStats = collections.namedtuple(
            "FlowStats",
            ["pg_id", "tx_packets", "rx_packets", "tx_bytes", "rx_bytes", ],
        )
        flow_stats = stats["flow_stats"].get(pg_id)
        ret = FlowStats(
            pg_id=pg_id,
            tx_packets=flow_stats["tx_pkts"]["total"],
            rx_packets=flow_stats["rx_pkts"]["total"],
            tx_bytes=flow_stats["tx_bytes"]["total"],
            rx_bytes=flow_stats["rx_bytes"]["total"],
        )
        return ret

    @staticmethod
    def __get_readable_flow_stats(stats):
        """
        :param stats: FlowStats
        :return:
        """
        return """Flow info for pg_id {}
        TX packets: {}
        RX packets: {}
        TX bytes: {}
        RX bytes: {}""".format(stats.pg_id, stats.tx_packets,
                               stats.rx_packets, stats.tx_bytes,
                               stats.rx_bytes)