from trex_stl_lib.api import *


# split the range of IP to cores 
# add tunable by fsize to change the size of the frame 
# latency frame is always 64 
# trex>start -f stl/udp_1pkt_src_ip_split_latency.py -t fsize=64 -m 30% --port 0 --force
#
#

class STLS1(object):

    def __init__ (self):
        self.fsize  =64;
        self.lfsize  =64;


    def create_stream (self, dir,port_id):
        # create a base packet and pad it to size
        size = self.fsize - 4; # no FCS

        if dir==0:
            src_ip="16.0.0.1"
            dst_ip="48.0.0.1"
        else:
            src_ip="48.0.0.1"
            dst_ip="16.0.0.1"

        base_pkt = Ether()/IP(src=src_ip,dst=dst_ip)/UDP(dport=12,sport=1025)

        pad = max(0, size - len(base_pkt)) * 'x'
        pad_latency = max(0, (self.lfsize-4) - len(base_pkt)) * 'x'
                             
        vm = STLScVmRaw( [   STLVmFlowVar ( "ip_src",  min_value="10.0.0.1",
                                            max_value="10.0.0.255", size=4, step=1,op="inc"),
                             STLVmWrFlowVar (fv_name="ip_src", pkt_offset= "IP.src" ), # write ip to packet IP.src
                             STLVmFixIpv4(offset = "IP")                                # fix checksum
                                  ]
                              ,split_by_field = "ip_src"  # split to cores base on the tuple generator 
                              ,cache_size =255 # the cache size
                              );

        pkt = STLPktBuilder(pkt = base_pkt/pad,
                            vm = vm)
        stream = [STLStream(packet = pkt,
                            mode = STLTXCont(pps=1)),


                  # latency stream   
                  STLStream(packet = STLPktBuilder(pkt = base_pkt/pad_latency),
                            mode = STLTXCont(pps=1000),
                            flow_stats = STLFlowLatencyStats(pg_id = 12+port_id))
  
        ]
        return stream


    def get_streams (self, direction = 0, fsize = 64,lfsize = 64, **kwargs):
        self.fsize  =fsize;
        self.lfsize =lfsize
        return self.create_stream(direction,kwargs['port_id'])


# dynamic load - used for trex console or simulator
def register():
    return STLS1()