ui.py

'''
ALOHA PROTOCOL SIMULATION

authors: George Evangelou, Nikos Roussos
date: July 2019
'''


import ini

def check_wrong_max(inp, min):
    return (inp<min)

def check_wrong_prob(inp):
    return (inp <= 0 or inp > 1)

def check_wrong(inp):
    return (inp <= 0)

def get_input():
    print('Now initializing simulation...')
    try: 
        bw = float(input("\nSet the bandwidth of the channel in bps: "))
    except Exception:
        bw = 0  #if an exception is raised, set a wrong value so that the default value is chosen instead
    if check_wrong(bw):
        print("Wrong input, defaulted to: ", ini.channel_bandwidth)
    else:
        ini.channel_bandwidth = bw

    try:
        bpp = int(input("\nSet the packet length (bits per packet): "))
    except Exception:
        bpp = 0  #if an exception is raised, set a wrong value so that the default value is chosen instead
    if check_wrong(bpp):
        print("Wrong input, defaulted to: ", ini.packet_length)
    else:
        ini.packet_length = bpp
    
    try:
        min_prob = float(input("\nSet the minimum probability of packet generation for every station: "))
    except Exception:
        min_prob = -1  #if an exception is raised, set a wrong value so that the default value is chosen instead
    if check_wrong_prob(min_prob):
        print("Wrong input, defaulted to: ", ini.min_probability)
    else:
        ini.min_probability = min_prob
       
    if (ini.max_probability<ini.min_probability):
        ini.max_probability = 1.1 * ini.min_probability
        if (ini.max_probability>1): ini.max_probability = 1

    try:
        max_prob = float(input("\nSet the maximum probability of packet generation for every station: "))
    except Exception:
        max_prob = 2  #if an exception is raised, set a wrong value so that the default value is chosen instead
    if ( check_wrong_prob(max_prob) or check_wrong_max(max_prob, ini.min_probability) ): #max_prob must not be outside [min_prob, 1] 
        print("Wrong input, defaulted to: ", ini.max_probability)
    else:
        ini.max_probability = max_prob

    try:
        qsize = int(input("\nSet the max queue size of every station: "))
    except Exception:
        qsize = -1  #if an exception is raised, set a wrong value so that the default value is chosen instead
    if check_wrong(qsize):
        print("Wrong input, defaulted to: ", ini.max_queue_size)
    else:
        ini.max_queue_size = qsize

    ini.bit_time = 1/ini.channel_bandwidth #seconds
    ini.time_slot = ini.bit_time * ini.packet_length #seconds
    print("\nSimulation was successfully configured")
    input("Press enter to start the simulation:")
    return

def runprogram():
    option = input('Enter "y" if you want to run another simulation: ')
    return (option=='y')