#!/usr/bin/python

import os
from optparse import OptionParser

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


# Parse command line options and dump results
def parseOptions():
    """Parse command line options"""
    parser = OptionParser()
    parser.add_option('--spine', dest='spine', type='int', default=2,
                      help='number of spine switches, default=2')
    parser.add_option('--leaf', dest='leaf', type='int', default=2,
                      help='number of leaf switches, default=2')
    parser.add_option('--fanout', dest='fanout', type='int', default=2,
                      help='number of hosts per leaf switch, default=2')
    (options, args) = parser.parse_args()
    return options, args


opts, args = parseOptions()


class LeafAndSpine(Topo):
    def __init__(self, spine=2, leaf=2, fanout=2, **opts):
        "Create Leaf and Spine Topo."

        Topo.__init__(self, **opts)

        # Add spine switches
        spines = {}
        for s in range(spine):
            spines[s] = self.addSwitch('spine40%s' % (s + 1))
        # Set link speeds to 100Mb/s
        linkopts = dict(bw=10)

        # Add Leaf switches
        for ls in range(leaf):
            leafSwitch = self.addSwitch('leaf%s' % (ls + 1))
            # Connect leaf to all spines
            for s in range(spine):
                switch = spines[s]
                self.addLink(leafSwitch, switch, **linkopts)
            # Add hosts under a leaf, fanout hosts per leaf switch 
            for f in range(fanout):
                host = self.addHost('h%s' % (ls * fanout + f + 1),
                                         cls=IpHost,  
                                         ip='10.0.%s.%s/24' % ((ls + 1), (f + 1)),
                                         gateway='10.0.%s.254' % (ls + 1))
                self.addLink(host, leafSwitch, **linkopts)

class IpHost(Host):
    def __init__(self, name, gateway, *args, **kwargs):
        super(IpHost, self).__init__(name, *args, **kwargs)
        self.gateway = gateway

    def config(self, **kwargs):
        Host.config(self, **kwargs)
        mtu = "ifconfig "+self.name+"-eth0 mtu 1490"
        self.cmd(mtu)
        self.cmd('ip route add default via %s' % self.gateway)


def config(opts):
    spine = opts.spine
    leaf = opts.leaf
    fanout = opts.fanout
    controllers= [ os.environ['OC%s' % i] for i in range(1,4) ]
    #controllers = ['127.0.0.1']
    topo = LeafAndSpine(spine=spine, leaf=leaf, fanout=fanout)
    net = Mininet(topo=topo, link=TCLink, build=False,
                  switch=UserSwitch,
                  controller = None,
                  autoSetMacs = True)
    i = 0
    for ip in controllers:
        net.addController( "c%s" % (i), controller=RemoteController, ip=ip)
        i += 1;
    net.build()
    net.start()
    CLI(net)
    net.stop()


if __name__ == '__main__':
    setLogLevel('info')
    config(opts)
    os.system('sudo mn -c')