import pytest

from password_generator.constants import LETTERS, NUMBERS, SYMBOLS
from password_generator.generator import generate_easy_password, generate_hard_password


def test_easy_password_is_ordered_letters_symbols_numbers():
    password = generate_easy_password(4, 2, 2)
    assert len(password) == 8
    assert all(c in LETTERS for c in password[:4])
    assert all(c in SYMBOLS for c in password[4:6])
    assert all(c in NUMBERS for c in password[6:])


def test_hard_password_has_requested_composition():
    password = generate_hard_password(5, 3, 4)
    assert len(password) == 12
    assert sum(c in LETTERS for c in password) == 5
    assert sum(c in SYMBOLS for c in password) == 3
    assert sum(c in NUMBERS for c in password) == 4


def test_hard_password_is_shuffled():
    # 20 letters then 20 numbers in that exact order is astronomically unlikely after a shuffle.
    results = {generate_hard_password(20, 0, 20) for _ in range(5)}
    assert any(not (p[:20].isalpha() and p[20:].isdigit()) for p in results)


def test_zero_counts_give_empty_password():
    assert generate_easy_password(0, 0, 0) == ""
    assert generate_hard_password(0, 0, 0) == ""


@pytest.mark.parametrize("func", [generate_easy_password, generate_hard_password])
def test_negative_counts_raise(func):
    with pytest.raises(ValueError):
        func(-1, 0, 0)