from playcrypt.primitives import *
from playcrypt.tools import *
from playcrypt.ideal.function_family import *
from playcrypt.games.game_prf import GamePRF
from playcrypt.simulator.world_sim import WorldSim
from playcrypt.ideal.block_cipher import BlockCipher

keyLen = 128
bcInLen = 3
bcOutLen = 3
PSEUDORANDOM = 1
RANDOM = 0

def A(fn):
    r"""
    The adversary to the PRF Challenger.

    :param fn: a function pointer that allows the adverseary to make queries to the challenger.  
               The challenger will respond to query x by:  
                   evaluating the PRF on x if the challenge bit is 1
                   evaluating a random function on x if the challenge bit is 0
    :return: 0 for RANDOM and 1 for PSEUDORANDOM.
    """
    print('------ new challenge -------')
    q1 = random_string(bcInLen)
    y = fn(q1)
    print('y:  ', string_to_binary(y))
    print('q1: ', string_to_binary(q1))
    if y == bitwise_complement_string(q1):
        print('must be the PRF! output is complement of input.')
        return PSEUDORANDOM
    else :
        print('must be a random function! output is not the complement of the input')
        return RANDOM

# DO NOT EDIT THIS FUNCTION #
def prf(k, x, b):
    r"""
    The candidate psuedorandom function.

    :param k: the secret key.
    :param x: the input value.
    :param b: a secure PRF. (not used in this example)
    :return: the psuedorandom output: F(k,x)
    """
    return bitwise_complement_string(x)

# Use this block for any printing/testing, do not leave stray print
# statements outside this block.
if __name__ == "__main__":
    
    g = GamePRF(2, prf, keyLen, bcInLen, bcOutLen, None)

    s = WorldSim(g, A)
#    print(s.compute_success_ratio(PSEUDORANDOM,1024))
#    print(s.compute_success_ratio(RANDOM,1024))
    print(str(s.compute_advantage(3)))