"""
ns3lte.py - This script demonstrates using CORE with the ns-3 LTE model.
*** Note that this script is not currently functional, see notes below. ***
- issues connecting TapBridge with LteNetDevice
"""

import optparse
import sys

import ns.core
import ns.mobility

from core import logger
from core.misc import ipaddress
from core.misc import nodemaps
from core.misc import nodeutils
from corens3.obj import Ns3LteNet
from corens3.obj import Ns3Session


def ltesession(opt):
    """
    Run a test LTE session.
    """
    nodeutils.set_node_map(nodemaps.NODES)
    session = Ns3Session(1, persistent=True, duration=opt.duration)
    lte = session.add_object(cls=Ns3LteNet, name="wlan1")
    lte.setsubchannels(range(25), range(50, 100))
    if opt.verbose:
        ascii = ns.network.AsciiTraceHelper()
        stream = ascii.CreateFileStream('/tmp/ns3lte.tr')
        lte.lte.EnableAsciiAll(stream)
        # ns.core.LogComponentEnable("EnbNetDevice", ns.core.LOG_LEVEL_INFO)
        # ns.core.LogComponentEnable("UeNetDevice", ns.core.LOG_LEVEL_INFO)
        # lte.lte.EnableLogComponents()

    prefix = ipaddress.Ipv4Prefix("10.0.0.0/16")
    mobb = None
    nodes = []
    for i in xrange(1, opt.numnodes + 1):
        node = session.addnode(name="n%d" % i)
        mob = ns.mobility.ConstantPositionMobilityModel()
        mob.SetPosition(ns.core.Vector3D(10.0 * i, 0.0, 0.0))
        if i == 1:
            # first node is nodeb
            lte.setnodeb(node)
            mobb = mob
        node.newnetif(lte, ["%s/%s" % (prefix.addr(i), prefix.prefixlen)])
        nodes.append(node)
        if i == 1:
            (tmp, ns3dev) = lte.findns3dev(node)
            lte.lte.AddMobility(ns3dev.GetPhy(), mob)
        if i > 1:
            lte.linknodeb(node, nodes[0], mob, mobb)

    session.thread = session.run(vis=opt.visualize)
    return session


def main():
    """
    Main routine when running from command-line.
    """
    usagestr = "usage: %prog [-h] [options] [args]"
    parser = optparse.OptionParser(usage=usagestr)
    parser.set_defaults(numnodes=4, duration=600, verbose=False, visualize=False)

    parser.add_option("-d", "--duration", dest="duration", type=int,
                      help="number of seconds to run the simulation")
    parser.add_option("-n", "--numnodes", dest="numnodes", type=int,
                      help="number of nodes")
    parser.add_option("-z", "--visualize", dest="visualize",
                      action="store_true", help="enable visualizer")
    parser.add_option("-v", "--verbose", dest="verbose",
                      action="store_true", help="be more verbose")

    def usage(msg=None, err=0):
        sys.stdout.write("\n")
        if msg:
            sys.stdout.write(msg + "\n\n")
        parser.print_help()
        sys.exit(err)

    opt, args = parser.parse_args()

    if opt.numnodes < 2:
        usage("invalid numnodes: %s" % opt.numnodes)

    for a in args:
        logger.warn("ignoring command line argument: '%s'", a)

    return ltesession(opt)


def cleanup():
    logger.info("shutting down session")
    session.shutdown()


if __name__ == "__main__":
    session = main()