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"""Traffic profile for T-rex advanced stateful (astf) traffic generator.
Traffic profile:
 - Two streams sent in directions 0 --> 1 (client -> server, requests) and
   1 --> 0 (server -> client, responses) at the same time.
 - Packet: ETH / IP / UDP
 - Direction 0 --> 1:
   - Source IP address range:      192.168.0.0 - 192.168.255.255
   - Destination IP address range: 20.0.0.0 - 20.0.255.255
 - Direction 1 --> 0:
   - Source IP address range:      destination IP address from packet received
     on port 1
   - Destination IP address range: source IP address from packet received
     on port 1

This is a profile for PPS tests, it combines UDP connect and data transfer.
No delays, server response waits for full request.
"""

from trex.astf.api import *
from profile_trex_astf_base_class import TrafficProfileBaseClass


class TrafficProfile(TrafficProfileBaseClass):
    """Traffic profile."""

    def define_profile(self):
        """Define profile to be used by advanced stateful traffic generator.

        This method MUST return:

            return ip_gen, templates, None

        :returns: IP generator and profile templates for ASTFProfile().
        :rtype: tuple
        """
        # IPs used in packet headers.
        p1_src_start_ip = u"192.168.0.0"
        p1_src_end_ip = u"192.168.255.255"
        p1_dst_start_ip = u"20.0.0.0"
        p1_dst_end_ip = u"20.0.255.255"

        # The difference between data size and frame size.
        headers_size = 46  # 18B L2 + 20B IPv4 + 8B UDP.

        # TODO: Use the "connection protocol" from CPS traffic profile?
        # Currently, the first data packet is all DUT sees about the session.

        # Avoid sending keepalives.
        m_delay = 2000000  # delay 2000s (2,000,000 ms)

        # Data, not padded yet.
        udp_data = u""
        # Pad the data to achieve the intended frame size.
        udp_data += self._gen_padding(headers_size)

        # Safety check, the current programs send at least 1 packet.
        if self.n_data_frames < 1:
            raise RuntimeError("n_data_frames < 1: {self.n_data_frames}")

        # Client program.
        prog_c = ASTFProgram(stream=False)
        prog_c.set_keepalive_msg(m_delay)
        prog_c.set_var(u"var1", self.n_data_frames)
        prog_c.set_label(u"a:")
        prog_c.send_msg(udp_data)
        prog_c.jmp_nz(u"var1", u"a:")
        # We should read the server response,
        # but no reason to overload client workers even more.

        # Server program.
        prog_s = ASTFProgram(stream=False)
        prog_s.set_keepalive_msg(m_delay)
        # If server closes too soon, new instances are started
        # leading in too much replies. To prevent that, we need to recv all.
        prog_s.recv_msg(self.n_data_frames)
        # In packet loss scenarios, some instances never get here.
        # This maybe increases server traffic duration,
        # but no other way if we want to avoid
        # TRex creating a second instance of the same server.
        prog_s.set_var(u"var2", self.n_data_frames)
        prog_s.set_label(u"b:")
        prog_s.send_msg(udp_data)
        prog_s.jmp_nz(u"var2", u"b:")
        # VPP never duplicates packets,
        # so it is safe to close the server instance now.

        # ip generators
        ip_gen_c = ASTFIPGenDist(
            ip_range=[p1_src_start_ip, p1_src_end_ip],
            distribution=u"seq",
        )
        ip_gen_s = ASTFIPGenDist(
            ip_range=[p1_dst_start_ip, p1_dst_end_ip],
            distribution=u"seq",
        )
        ip_gen = ASTFIPGen(
            glob=ASTFIPGenGlobal(ip_offset=u"0.0.0.1"),
            dist_client=ip_gen_c,
            dist_server=ip_gen_s,
        )

        # server association
        s_assoc = ASTFAssociation(rules=ASTFAssociationRule(port=8080))

        # template
        temp_c = ASTFTCPClientTemplate(
            program=prog_c,
            ip_gen=ip_gen,
            limit=4128768,  # TODO: Any benefit of making this configurable?
            port=8080,
        )
        temp_s = ASTFTCPServerTemplate(program=prog_s, assoc=s_assoc)
        template = ASTFTemplate(client_template=temp_c, server_template=temp_s)

        return ip_gen, template, None


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

    Do not change this function.

    :return: Traffic Profiles.
    :rtype: Object
    """
    return TrafficProfile()