#!/usr/bin/env python3

# Copyright (c) 2021 Intel and/or its affiliates.
#
# SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
#
# Licensed under the Apache License 2.0 or
# GNU General Public License v2.0 or later;  you may not use this file
# except in compliance with one of these Licenses. You
# may obtain a copy of the Licenses at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#     https://www.gnu.org/licenses/old-licenses/gpl-2.0-standalone.html
#
# Note: If this file is linked with Scapy, which is GPLv2+, your use of it
# must be under GPLv2+.  If at any point in the future it is no longer linked
# with Scapy (or other GPLv2+ licensed software), you are free to choose
# Apache 2.
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Traffic script that send flow packet from one interface
to the other.
"""

import sys
import binascii

from scapy.layers.inet import IP, UDP, TCP
from scapy.layers.inet6 import IPv6
from scapy.layers.l2 import Ether, ARP
from scapy.packet import Raw
from scapy.contrib.gtp import GTP_U_Header
from scapy.layers.ipsec import ESP, AH
from scapy.layers.vxlan import VXLAN

from .PacketVerifier import TxQueue
from .TrafficScriptArg import TrafficScriptArg


def main():
    """Send packet from one traffic generator interface to the other."""

    args = TrafficScriptArg(
        [
            u"tg_if1_mac", u"dut_if1_mac", u"flow_type", u"proto",
        ],
        [
            u"src_ip", u"dst_ip", u"src_port", u"dst_port", u"value"
        ]
    )
    tx_if = args.get_arg(u"tx_if")
    tx_src_mac = args.get_arg(u"tg_if1_mac")
    tx_dst_mac = args.get_arg(u"dut_if1_mac")
    flow_type = args.get_arg(u"flow_type")
    proto = args.get_arg(u"proto")

    src = args.get_arg(u"src_ip")
    dst = args.get_arg(u"dst_ip")
    sport = eval(args.get_arg(u"src_port"))
    dport = eval(args.get_arg(u"dst_port"))
    value = eval(args.get_arg(u"value"))

    txq = TxQueue(tx_if)

    if flow_type == u"IP4":
        pkt_raw = (Ether(src=tx_src_mac, dst=tx_dst_mac) /
                   IP(src=src, dst=dst))
    elif flow_type == u"IP6":
        pkt_raw = (Ether(src=tx_src_mac, dst=tx_dst_mac) /
                   IPv6(src=src, dst=dst))
    elif flow_type == u"ETHER":
        pkt_raw = Ether(src=tx_src_mac, dst=tx_dst_mac)
    else:
        raise ValueError(f"Flow type error: {flow_type}")

    if proto == u"TCP":
        pkt_raw /= TCP(sport=sport, dport=dport)
    elif proto == u"UDP":
        pkt_raw /= UDP(sport=sport, dport=dport)
    elif proto == u"AH":
        pkt_raw /= AH(spi=value)
    elif proto == u"ESP":
        pkt_raw /= ESP(spi=value)
    elif proto == u"GTPU":
        pkt_raw /= (UDP()/GTP_U_Header(teid=value)/IP(src=u"192.168.10.20"))
    elif proto == u"L2TPV3":
        value_hex = hex(value).replace('0x', (8-len(hex(value))+2)*'0')
        session_id = binascii.a2b_hex(value_hex)
        pkt_raw.proto = 115
        pkt_raw /= Raw(session_id)
    elif proto == u"VXLAN":
        pkt_raw /= (UDP()/VXLAN(vni=value))
    elif proto == u"ARP":
        pkt_raw.type = value
        pkt_raw /= ARP()
    else:
        raise ValueError(f"Flow proto error: {proto}")

    pkt_raw /= Raw()
    txq.send(pkt_raw)
    sys.exit(0)

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