from pyrsistent import freeze, inc, discard, rex, ny, field, PClass


def test_callable_command():
    m = freeze({'foo': {'bar': {'baz': 1}}})
    assert m.transform(['foo', 'bar', 'baz'], inc) == {'foo': {'bar': {'baz': 2}}}


def test_predicate():
    m = freeze({'foo': {'bar': {'baz': 1}, 'qux': {'baz': 1}}})
    assert m.transform(['foo', lambda x: x.startswith('b'), 'baz'], inc) == {'foo': {'bar': {'baz': 2}, 'qux': {'baz': 1}}}


def test_broken_predicate():
    broken_predicates = [
        lambda: None,
        lambda a, b, c: None,
        lambda a, b, c, d=None: None,
        lambda *args: None,
        lambda **kwargs: None,
    ]
    for pred in broken_predicates:
        try:
            freeze({}).transform([pred], None)
            assert False
        except ValueError as e:
            assert str(e) == "callable in transform path must take 1 or 2 arguments"


def test_key_value_predicate():
    m = freeze({
        'foo': 1,
        'bar': 2,
    })
    assert m.transform([
        lambda k, v: (k, v) == ('foo', 1),
    ], lambda v: v * 3) == {"foo": 3, "bar": 2}


def test_remove():
    m = freeze({'foo': {'bar': {'baz': 1}}})
    assert m.transform(['foo', 'bar', 'baz'], discard) == {'foo': {'bar': {}}}


def test_remove_pvector():
    m = freeze({'foo': [1, 2, 3]})
    assert m.transform(['foo', 1], discard) == {'foo': [1, 3]}


def test_remove_pclass():
    class MyClass(PClass):
        a = field()
        b = field()

    m = freeze({'foo': MyClass(a=1, b=2)})
    assert m.transform(['foo', 'b'], discard) == {'foo': MyClass(a=1)}


def test_predicate_no_match():
    m = freeze({'foo': {'bar': {'baz': 1}}})
    assert m.transform(['foo', lambda x: x.startswith('c'), 'baz'], inc) == m


def test_rex_predicate():
    m = freeze({'foo': {'bar': {'baz': 1},
                        'bof': {'baz': 1}}})
    assert m.transform(['foo', rex('^bo.*'), 'baz'], inc) == {'foo': {'bar': {'baz': 1},
                                                                      'bof': {'baz': 2}}}


def test_rex_with_non_string_key():
    m = freeze({'foo': 1, 5: 2})
    assert m.transform([rex(".*")], 5) == {'foo': 5, 5: 2}


def test_ny_predicated_matches_any_key():
    m = freeze({'foo': 1, 5: 2})
    assert m.transform([ny], 5) == {'foo': 5, 5: 5}


def test_new_elements_created_when_missing():
    m = freeze({})
    assert m.transform(['foo', 'bar', 'baz'], 7) == {'foo': {'bar': {'baz': 7}}}


def test_mixed_vector_and_map():
    m = freeze({'foo': [1, 2, 3]})
    assert m.transform(['foo', 1], 5) == freeze({'foo': [1, 5, 3]})


def test_vector_predicate_callable_command():
    v = freeze([1, 2, 3, 4, 5])
    assert v.transform([lambda i: 0 < i < 4], inc) == freeze(freeze([1, 3, 4, 5, 5]))


def test_vector_insert_map_one_step_beyond_end():
    v = freeze([1, 2])
    assert v.transform([2, 'foo'], 3) == freeze([1, 2, {'foo': 3}])


def test_multiple_transformations():
    v = freeze([1, 2])
    assert v.transform([2, 'foo'], 3, [2, 'foo'], inc) == freeze([1, 2, {'foo': 4}])


def test_no_transformation_returns_the_same_structure():
    v = freeze([{'foo': 1}, {'bar': 2}])
    assert v.transform([ny, ny], lambda x: x) is v


def test_discard_multiple_elements_in_pvector():
    assert freeze([0, 1, 2, 3, 4]).transform([lambda i: i % 2], discard) == freeze([0, 2, 4])
