import mock
import pytest

from netlib import encoding, tutils


def test_identity():
    assert b"string" == encoding.decode(b"string", "identity")
    assert b"string" == encoding.encode(b"string", "identity")
    with tutils.raises(ValueError):
        encoding.encode(b"string", "nonexistent encoding")


@pytest.mark.parametrize("encoder", [
    'gzip',
    'br',
    'deflate',
])
def test_encoders(encoder):
    assert "" == encoding.decode("", encoder)
    assert b"" == encoding.decode(b"", encoder)

    assert "string" == encoding.decode(
        encoding.encode(
            "string",
            encoder
        ),
        encoder
    )
    assert b"string" == encoding.decode(
        encoding.encode(
            b"string",
            encoder
        ),
        encoder
    )

    with tutils.raises(ValueError):
        encoding.decode(b"foobar", encoder)


def test_cache():
    decode_gzip = mock.MagicMock()
    decode_gzip.return_value = b"decoded"
    encode_gzip = mock.MagicMock()
    encode_gzip.return_value = b"encoded"

    with mock.patch.dict(encoding.custom_decode, gzip=decode_gzip):
        with mock.patch.dict(encoding.custom_encode, gzip=encode_gzip):
            assert encoding.decode(b"encoded", "gzip") == b"decoded"
            assert decode_gzip.call_count == 1

            # should be cached
            assert encoding.decode(b"encoded", "gzip") == b"decoded"
            assert decode_gzip.call_count == 1

            # the other way around as well
            assert encoding.encode(b"decoded", "gzip") == b"encoded"
            assert encode_gzip.call_count == 0

            # different encoding
            decode_gzip.return_value = b"bar"
            assert encoding.encode(b"decoded", "deflate") != b"decoded"
            assert encode_gzip.call_count == 0

            # This is not in the cache anymore
            assert encoding.encode(b"decoded", "gzip") == b"encoded"
            assert encode_gzip.call_count == 1