import random

import pytest

from pyecsca.ec.mult import LTRMultiplier
from pyecsca.sca.attack.CPA import CPA
from pyecsca.sca.attack.DPA import DPA
from pyecsca.sca.attack.leakage_model import HammingWeight, NormalNoice
from pyecsca.sca.target import LeakageTarget


@pytest.fixture()
def mult(secp128r1):
    return LTRMultiplier(
        secp128r1.curve.coordinate_model.formulas["add-2015-rcb"],
        secp128r1.curve.coordinate_model.formulas["dbl-2015-rcb"],
    )


@pytest.fixture()
def target(secp128r1, mult):
    target = LeakageTarget(
        secp128r1.curve.model, secp128r1.curve.coordinate_model, mult, HammingWeight()
    )
    target.set_params(secp128r1)
    return target


def test_dpa(secp128r1, mult, target, mocker):
    random.seed(1337)

    def randbelow(n):
        return random.randrange(n)

    mocker.patch("secrets.randbelow", randbelow)
    scalar = 5
    pub = secp128r1.curve.affine_multiply(
        secp128r1.generator.to_affine(), scalar
    ).to_model(secp128r1.curve.coordinate_model, secp128r1.curve)
    points, traces = target.simulate_scalar_mult_traces(200, scalar)
    dpa = DPA(points, traces, mult, secp128r1)
    res = dpa.perform(3, pub)
    assert res == 5


def test_cpa(secp128r1, mult, target, mocker):
    random.seed(1337)

    def randbelow(n):
        return random.randrange(n)

    mocker.patch("secrets.randbelow", randbelow)
    scalar = 5
    pub = secp128r1.curve.affine_multiply(
        secp128r1.generator.to_affine(), scalar
    ).to_model(secp128r1.curve.coordinate_model, secp128r1.curve)
    points, original_traces = target.simulate_scalar_mult_traces(100, scalar)

    for _ in range(5):
        noise = NormalNoice(0, 2)
        traces = [noise(trace) for trace in original_traces]
        cpa = CPA(points, traces, HammingWeight(), mult, secp128r1)
        res = cpa.perform(3, pub)
        assert res == 5