import os
import struct
import time
from socket import *
import sys
from subprocess import call


def clear():
    _ = call('clear' if os.name =='posix' else 'cls')

def mainMenu():
    clear()
    print("===================\n"
          "     MAIN MENU\n"
          "\n   Disconnected\n"
          "===================")
    print("1. Set PC as client\n"
          "2. Set PC as server\n"
          "3.Change IP address\n"
          "4.Change PORT\n")
    print("5. Exit")
    selection = int(input("Select: "))
    if selection==1:
        start_client()
    elif selection==2:
        start_server()
    elif selection==3:
        exit()
    else:
        print("Vyber cislo z menu!")
        mainMenu()

def start_client():
    content = None
    host = "127.0.0.1"
    port = 10050
    size_of_fragment = 1024
    UDPSock = socket(AF_INET, SOCK_DGRAM)

    def client_menu1(host, port):
        addr = (host, port)
        if connect(addr):
            clear()
            print("====Connected!====")
            print("==================\n"
                  "CLIENT MENU\n"
                  f"IP: {host}\n"
                  f"PORT: {port}\n"
                  f"Fragment size: {size_of_fragment}\n"
                  "==================\n")
            print("1.Change size of fragment")
            selection = int(input("Select: "))
            if selection == 1:
                host = client_set_ip()
                client_menu1(host, port)
            elif selection == 2:
                client_set_port()
            elif selection == 3:
                exit()
            else:
                print("Vyber cislo z menu!")
                client_menu1(host, port)
        else:
            mainMenu()

    def client_set_ip():
        host = input("Zadaj IP adresu kam chces posielat v tvare xxx.xxx.xxx.xxx\n")
        return host

    def client_size_of_fragment():
        size_of_fragment = input("Zadaj velkost fragmentu - max 1024, min - 13") #este treba upravit
        return  size_of_fragment

    # file_name = print("Zadaj nazov suboru aj s cestou\n")
    # with open('file_name', 'rb') as f:
    #     content = f.read()

    def header_connection_msg():
        type = 0 #0 connection, 1 - info, 2 - data_head
        size_fragments = 1500#user_edit
        num_fragments = 1 #sizeofMSG/sizeoffragments
        type_of_msg = 0 #0 - text, 1 - file
        #checksum = CRC
        header = struct.pack("cHHc", b'0', size_fragments, num_fragments, b'0')
        return header

    def connect(addr):
        datap = header_connection_msg()
        success = 1
        time = 0
        while True:
            time = time + 1
            print(f"{time}Pripajam")
            UDPSock.sendto(datap, addr)
            UDPSock.settimeout(0.5)
            try:
                success, addr = UDPSock.recvfrom(1024)
            except error:
                success = None
            if success is not None:
                return True
            if time > 30:
                break



    client_menu1(host, port)

    while True:
         data = input("Zadaj spravu")
         UDPSock.sendto(data.encode(), addr)
         (datap, addr) = UDPSock.recvfrom(1024)
         print(datap.decode())
         if data == "exit":
             break

    UDPSock.close()
    os._exit(0)

def start_server():
    host = "127.0.0.1"
    port = 10050
    buf = 1024
    address = (host, port)
    p = 0
    UDPSock = socket(AF_INET, SOCK_DGRAM)
    UDPSock.bind(address)
    while True:
        (header, address) = UDPSock.recvfrom(500)
        type, size_fragments, num_fragments, type_of_msg = struct.unpack("cHHc", header)
        if type == b'0':
            break

    if type == b'0':
        p = b'0'
    print(f"lol")
    UDPSock.sendto(p, address)

    print('Server caka')

    while True:
        (data, address) = UDPSock.recvfrom(5)
        data1 = "Server prijal spravu"
        UDPSock.sendto(data1.encode(), address)
        print(f"Received message: {sys.getsizeof(data)}")
        print(f"Received message: {data}")
        if data == b"exit":
            break

    UDPSock.close()
    os._exit(0)

mainMenu()