#!/usr/bin/python

import os
import sys
import argparse

# Find and import bmv2.py
if 'ONOS_ROOT' not in os.environ:
    print "Environment var $ONOS_ROOT not set"
    exit()
else:
    sys.path.append(os.environ["ONOS_ROOT"] + "/tools/dev/mininet")
    from bmv2 import ONOSBmv2Switch

from itertools import combinations
from time import sleep

from mininet.cli import CLI
from mininet.link import TCLink
from mininet.log import setLogLevel
from mininet.net import Mininet
from mininet.node import RemoteController, Host
from mininet.topo import Topo


class ClosTopo(Topo):
    "2 stage Clos topology"

    def __init__(self, **opts):
        # Initialize topology and default options
        Topo.__init__(self, **opts)

        bmv2SwitchIds = ["s11", "s12", "s13", "s21", "s22", "s23"]

        bmv2Switches = {}

        tport = 9090
        for switchId in bmv2SwitchIds:
            bmv2Switches[switchId] = self.addSwitch(switchId,
                                                    cls=ONOSBmv2Switch,
                                                    loglevel="warn",
                                                    deviceId=int(switchId[1:]),
                                                    thriftPort=tport)
            tport += 1

        for i in (1, 2, 3):
            for j in (1, 2, 3):
                if i == j:
                    # 2 links
                    self.addLink(bmv2Switches["s1%d" % i], bmv2Switches["s2%d" % j],
                                 cls=TCLink, bw=50)
                    self.addLink(bmv2Switches["s1%d" % i], bmv2Switches["s2%d" % j],
                                 cls=TCLink, bw=50)
                else:
                    self.addLink(bmv2Switches["s1%d" % i], bmv2Switches["s2%d" % j],
                                 cls=TCLink, bw=50)

        for hostId in (1, 2, 3):
            host = self.addHost("h%d" % hostId,
                                cls=DemoHost,
                                ip="10.0.0.%d/24" % hostId,
                                mac='00:00:00:00:00:%02x' % hostId)
            self.addLink(host, bmv2Switches["s1%d" % hostId], cls=TCLink, bw=22)


class DemoHost(Host):
    "Demo host"

    def __init__(self, name, inNamespace=True, **params):
        Host.__init__(self, name, inNamespace=inNamespace, **params)
        self.exectoken = "/tmp/mn-exec-token-host-%s" % name
        self.cmd("touch %s" % self.exectoken)

    def config(self, **params):
        r = super(Host, self).config(**params)

        self.defaultIntf().rename("eth0")

        for off in ["rx", "tx", "sg"]:
            cmd = "/sbin/ethtool --offload eth0 %s off" % off
            self.cmd(cmd)

        # disable IPv6
        self.cmd("sysctl -w net.ipv6.conf.all.disable_ipv6=1")
        self.cmd("sysctl -w net.ipv6.conf.default.disable_ipv6=1")
        self.cmd("sysctl -w net.ipv6.conf.lo.disable_ipv6=1")

        return r

    def startPingBg(self, h):
        self.cmd(self.getInfiniteCmdBg("ping -i0.5 %s" % h.IP()))
        self.cmd(self.getInfiniteCmdBg("arping -w5000000 %s" % h.IP()))

    def startIperfServer(self):
        self.cmd(self.getInfiniteCmdBg("iperf3 -s"))

    def startIperfClient(self, h, flowBw="512k", numFlows=5, duration=5):
        iperfCmd = "iperf3 -c{} -b{} -P{} -t{}".format(h.IP(), flowBw, numFlows, duration)
        self.cmd(self.getInfiniteCmdBg(iperfCmd, sleep=0))

    def stop(self):
        self.cmd("killall iperf3")
        self.cmd("killall ping")
        self.cmd("killall arping")

    def describe(self):
        print "**********"
        print self.name
        print "default interface: %s\t%s\t%s" % (
            self.defaultIntf().name,
            self.defaultIntf().IP(),
            self.defaultIntf().MAC()
        )
        print "**********"

    def getInfiniteCmdBg(self, cmd, logfile="/dev/null", sleep=1):
        return "(while [ -e {} ]; " \
               "do {}; " \
               "sleep {}; " \
               "done;) > {} 2>&1 &".format(self.exectoken, cmd, sleep, logfile)

    def getCmdBg(self, cmd, logfile="/dev/null"):
        return "{} > {} 2>&1 &".format(cmd, logfile)


def main(args):
    topo = ClosTopo()

    net = Mininet(topo=topo, build=False)

    net.addController('c0', controller=RemoteController, ip=args.onos_ip, port=args.onos_port)

    net.build()
    net.start()

    print "Network started..."

    # Generates background traffic (needed for host discovery and bmv2 config swap).
    sleep(3)
    for (h1, h2) in combinations(net.hosts, 2):
        h1.startPingBg(h2)
        h2.startPingBg(h1)

    for h in net.hosts:
        h.startIperfServer()

    print "Background ping started..."

    # sleep(4)
    # print "Starting traffic from h1 to h3..."
    # net.hosts[0].startIperfClient(net.hosts[-1], flowBw="200k", numFlows=100, duration=10)

    CLI(net)

    net.stop()


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='BMv2 mininet demo script (2-stage Clos topology)')
    parser.add_argument('--onos-ip', help='ONOS-BMv2 controller IP address',
                        type=str, action="store", required=True)
    parser.add_argument('--onos-port', help='ONOS-BMv2 controller port',
                        type=int, action="store", default=40123)
    args = parser.parse_args()
    setLogLevel('info')
    main(args)