import sys, random
sys.path.append("../")

import functions.functions as fn


def dodawanie(punkt1, punkt2, krzywa):
    a = krzywa[0]
    p = krzywa[2]

    if punkt1 == None:
        return punkt2

    elif punkt2 == None:
        return punkt1
    
    elif punkt1[0] != punkt2[0]:
        l = ((punkt2[1] - punkt1[1]) * fn.odwrotnosc((punkt2[0] - punkt1[0]) % p, p) ) % p
        x3 = (fn.potegowanieimod(l, 2, p) - punkt1[0] - punkt2[0]) % p
        y3 = (l * (punkt1[0] - x3) - punkt1[1] ) % p
        return (x3, y3)

    elif punkt1[0] == punkt2[0] and punkt1[1] == punkt2[1]:
        l = ((3 * fn.potegowanieimod(punkt1[0], 2, p) + a) * fn.odwrotnosc(2 * punkt1[1], p)) % p
        x3 = (fn.potegowanieimod(l, 2, p) - 2 * punkt1[0]) % p
        y3 = (l * (punkt1[0] - x3) - punkt1[1]) % p
        return (x3, y3)

    elif punkt1[0] == przeciwny(punkt2)[0] and punkt1[1] == przeciwny(punkt2)[1]:
        return None

    return (0, 0)
    

def przeciwny(punkt, p):
    return (punkt[0],  -punkt[1] % p)