#! /usr/bin/env python

# standard modules
import logging
import os
import sys
import time

from six.moves import input

# ostinato modules 
# (user scripts using the installed package should prepend ostinato. i.e
#  ostinato.core and ostinato.protocols)
from .core import ost_pb, DroneProxy
from .protocols.mac_pb2 import mac, Mac
from .protocols.ip4_pb2 import ip4, Ip4

# initialize defaults
use_defaults = False
host_name = '127.0.0.1'
tx_port_number = 0
rx_port_number = 0

# setup logging
log = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO)

# command-line option/arg processing
if len(sys.argv) > 1:
    if sys.argv[1] in ('-d', '--use-defaults'):
        use_defaults = True
    if sys.argv[1] in ('-h', '--help'):
        print('%s [OPTION]...' % (sys.argv[0]))
        print('Options:')
        print(' -d --use-defaults   run using default values')
        print(' -h --help           show this help')
        sys.exit(0)

print('')
print('This example expects the following topology -')
print('')
print(' +-------+          +-------+')
print(' |       |Tx--->----|       |')
print(' | Drone |          |  DUT  |')
print(' |       |Rx---<----|       |')
print(' +-------+          +-------+')
print('')
print('Drone has 2 ports connected to DUT. Packets sent on the Tx port')
print('are expected to be received back on the Rx port')
print('')
print('An easy way to simulate the above topology is to select the loopback')
print('port as both Tx and Rx ports')
print('')

if not use_defaults:
    s = input('Drone\'s Hostname/IP [%s]: ' % (host_name))
    host_name = s or host_name

drone = DroneProxy(host_name)

try:
    # connect to drone
    log.info('connecting to drone(%s:%d)' 
            % (drone.hostName(), drone.portNumber()))
    drone.connect()

    # retreive port id list
    log.info('retreiving port list')
    port_id_list = drone.getPortIdList()

    # retreive port config list
    log.info('retreiving port config for all ports')
    port_config_list = drone.getPortConfig(port_id_list)

    if len(port_config_list.port) == 0:
        log.warning('drone has no ports!')
        sys.exit(1)

    # print port list and get tx/rx port id 
    print('Port List')
    print('---------')
    for port in port_config_list.port:
        print('%d.%s (%s)' % (port.port_id.id, port.name, port.description))
        # use a loopback port as default tx/rx port 
        if ('lo' in port.name or 'loopback' in port.description.lower()):
            tx_port_number = port.port_id.id
            rx_port_number = port.port_id.id

    if use_defaults:
        log.info('using port %d for tx/rx' % tx_port_number)
    else:
        p = input('Tx Port Id [%d]: ' % (tx_port_number))
        if p:
            tx_port_number = int(p)

        p = input('Rx Port Id [%d]: ' % (rx_port_number))
        if p:
            rx_port_number = int(p)

    tx_port = ost_pb.PortIdList()
    tx_port.port_id.add().id = tx_port_number;

    rx_port = ost_pb.PortIdList()
    rx_port.port_id.add().id = rx_port_number;

    # add a stream
    stream_id = ost_pb.StreamIdList()
    stream_id.port_id.CopyFrom(tx_port.port_id[0])
    stream_id.stream_id.add().id = 1
    log.info('adding tx_stream %d' % stream_id.stream_id[0].id)
    drone.addStream(stream_id)

    # configure the stream
    stream_cfg = ost_pb.StreamConfigList()
    stream_cfg.port_id.CopyFrom(tx_port.port_id[0])
    s = stream_cfg.stream.add()
    s.stream_id.id = stream_id.stream_id[0].id
    s.core.is_enabled = True
    s.control.num_packets = 5

    # setup stream protocols as mac:eth2:ip4:udp:payload
    p = s.protocol.add()
    p.protocol_id.id = ost_pb.Protocol.kMacFieldNumber
    p.Extensions[mac].dst_mac_mode = Mac.e_mm_fixed
    p.Extensions[mac].src_mac_mode = Mac.e_mm_fixed
    p.Extensions[mac].dst_mac = 0x001122334455
    p.Extensions[mac].src_mac = 0x00aabbccddee

    p = s.protocol.add()
    p.protocol_id.id = ost_pb.Protocol.kEth2FieldNumber

    p = s.protocol.add()
    p.protocol_id.id = ost_pb.Protocol.kIp4FieldNumber
    # reduce typing by creating a shorter reference to p.Extensions[ip4]
    ip = p.Extensions[ip4]
    ip.src_ip = 0x01020304
    ip.dst_ip = 0x05060708
    ip.dst_ip_mode = Ip4.e_im_inc_host

    s.protocol.add().protocol_id.id = ost_pb.Protocol.kUdpFieldNumber
    s.protocol.add().protocol_id.id = ost_pb.Protocol.kPayloadFieldNumber

    log.info('configuring tx_stream %d' % stream_id.stream_id[0].id)
    drone.modifyStream(stream_cfg)

    # prebuild all packets to be sent before actually sending them
    build_cfg = ost_pb.BuildConfig()
    build_cfg.port_id.CopyFrom(tx_port.port_id[0])
    ack = drone.build(build_cfg)
    if (ack.status): # error?
        log.error('packets prebuild error: %s' % ack.notes)

    # clear tx/rx stats
    log.info('clearing tx/rx stats')
    drone.clearStats(tx_port)
    drone.clearStats(rx_port)

    # start capture and transmit
    log.info('starting capture')
    drone.startCapture(rx_port)
    log.info('starting transmit')
    drone.startTransmit(tx_port)

    # wait for transmit to finish
    log.info('waiting for transmit to finish ...')
    time.sleep(7)

    # stop transmit and capture
    log.info('stopping transmit')
    drone.stopTransmit(tx_port)
    log.info('stopping capture')
    drone.stopCapture(rx_port)

    # get tx/rx stats
    log.info('retreiving stats')
    tx_stats = drone.getStats(tx_port)
    rx_stats = drone.getStats(rx_port)

    #log.info('--> (tx_stats)' + tx_stats.__str__())
    #log.info('--> (rx_stats)' + rx_stats.__str__())
    log.info('tx pkts = %d, rx pkts = %d' % 
            (tx_stats.port_stats[0].tx_pkts, rx_stats.port_stats[0].rx_pkts))

    # retrieve and dump received packets
    log.info('getting Rx capture buffer')
    buff = drone.getCaptureBuffer(rx_port.port_id[0])
    drone.saveCaptureBuffer(buff, 'capture.pcap')
    log.info('dumping Rx capture buffer')
    os.system('tshark -r capture.pcap')
    os.remove('capture.pcap')

    # delete streams
    log.info('deleting tx_stream %d' % stream_id.stream_id[0].id)
    drone.deleteStream(stream_id)

    # bye for now
    drone.disconnect()

except Exception as ex:
    log.exception(ex)
    sys.exit(1)