# Copyright (c) 2020 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# 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.

"""Stream profile for T-rex traffic generator.

Stream profile:
 - One stream sent in directions 0 --> 1.
 - Packet: ETH / IP / UDP
 - Direction 0 --> 1:
   - Source IP address range:      192.168.0.0 - 192.168.3.255
   - Destination IP address range: 20.0.0.0 - 20.0.3.255
   - Source UDP port range:        1024 - 1086
   - Destination UDP port range:   8080
"""

from trex.stl.api import *
from profile_trex_stateless_base_class import TrafficStreamsBaseClass


class TrafficStreams(TrafficStreamsBaseClass):
    """Stream profile."""

    def __init__(self):
        """Initialization and setting of streams' parameters."""

        super(TrafficStreamsBaseClass, self).__init__()

        # IPs used in packet headers.
        self.p1_src_start_ip = u"192.168.0.0"
        self.p1_src_end_ip = u"192.168.3.255"
        self.p1_dst_start_ip = u"20.0.0.0"
        self.p1_dst_end_ip = u"20.0.3.255"

        # UDP ports used in packet headers.
        self.p1_src_start_udp_port = 1024
        self.p1_src_end_udp_port = 1086
        self.p1_dst_start_udp_port = 8080
        self.p1_dst_end_udp_port = 8080

    def define_packets(self):
        """Defines the packets to be sent from the traffic generator.

        Packet definition: | ETH | IP | UDP |

        :returns: Packets to be sent from the traffic generator.
        :rtype: tuple
        """

        # Direction 0 --> 1
        base_pkt_a = (
            Ether() /
            IP(
                src=self.p1_src_start_ip,
                dst=self.p1_dst_start_ip,
                proto=17
            ) /
            UDP(
                sport=self.p1_src_start_udp_port,
                dport=self.p1_dst_start_udp_port
            )
        )

        base_pkt_b = (
            Ether()
        )

        # Direction 0 --> 1
        vm1 = STLVM()
        vm1.var(name="sIP",
                min_value=self.p1_src_start_ip,
                max_value=self.p1_src_end_ip,
                size=4,
                op="inc",
                next_var="sport")
        vm1.var(name="sport",
                min_value=self.p1_src_start_udp_port,
                max_value=self.p1_src_end_udp_port,
                size=2,
                op="inc")
        vm1.var(name="dIP",
                min_value=self.p1_dst_start_ip,
                max_value=self.p1_dst_end_ip,
                size=4,
                op="inc")
        vm1.var(name="dport",
                min_value=self.p1_dst_start_udp_port,
                max_value=self.p1_dst_end_udp_port,
                size=2,
                op="inc")
        vm1.write(fv_name="sIP", pkt_offset="IP.src")
        vm1.write(fv_name="sport", pkt_offset="UDP.sport")
        vm1.write(fv_name="dIP", pkt_offset="IP.dst")
        vm1.write(fv_name="dport", pkt_offset="UDP.dport")
        vm1.fix_chksum(offset='IP')

        vm2 = STLVM()

        return base_pkt_a, base_pkt_b, vm1, vm2

def register():
    """Register this traffic profile to T-rex.

    Do not change this function.

    :return: Traffic streams.
    :rtype: Object
    """
    return TrafficStreams()