import sys
from scapy.all import sniff, send, IP, IPv6, Packet, Raw, Ether, sendp, base64_bytes, hex_bytes,bytes_base64
from scapy.layers.inet import UDP
from scapy.layers.rtp import RTP, bind_layers
from datetime import datetime

def invert_byte(byte):
    return ~byte & 0xFF

def modify_packet(packet: Packet):
    global modifications
    global seen


    udp: Packet = packet[UDP]
    # udp.show()
    if RTP in udp:
        rtp: Packet = udp[RTP]
        # load: bytes = rtp.load
        if rtp.payload_type == 96:
            print("96")
            # payload: bytes = rtp.payload.load
            # pretty = bytes_base64(payload)
            # print(payload)
            # hex: str = payload.hex()
            # new_hex = hex[::-1]
            # print(hex)
            # print()
            # print(new_hex)
            # print(type(new_payload))
            # rtp.payload = Raw(hex_bytes(new_hex))
            original_payload = bytes(rtp.payload)
            new_payload_hex = "deadbeef"  # New payload in hex format
            new_payload = bytes.fromhex(new_payload_hex)
            rtp.payload = Raw(new_payload)
            udp.len = len(udp)
            udp.chksum = None  # Recalculate checksum
            # payload[6] = invert_byte(payload[6])
        else:
            print('npe')



    seen += 1
    sendp(packet, iface=sys.argv[1])


if __name__ == "__main__":
    modifications = 0
    seen = 0
    if len(sys.argv) != 2:
        print(f"Usage: {sys.argv[0]} <interface>")
        sys.exit(1)

    interface = sys.argv[1]

    start_time = datetime.now()
    print(f"Script started at: {start_time.strftime('%Y-%m-%d %H:%M:%S')}")
    bind_layers(UDP, RTP, sport=6970)
    packets = sniff(filter="udp port 6970", iface=interface, timeout=60*1, prn=modify_packet)

    end_time = datetime.now()
    print(f"Script ended at: {end_time.strftime('%Y-%m-%d %H:%M:%S')}")
    print(f"{modifications} ip(v6) packets modified")
    print(f"{seen} total ip(v6) packets seen")