from __future__ import annotations

from pathlib import Path

import numpy as np
import pytest

from galileo_rx.signal_profiles import galileo_e1_profile
from galileo_rx.signals.signalsim_codes import SignalSimCodeProvider


def _checkout() -> Path:
    candidates = [Path("signalsim/SignalSim"), Path("../SignalSim"), Path("../signalsim/SignalSim")]
    for candidate in candidates:
        if (candidate / "src" / "MemoryCode.dat").is_file():
            return candidate.resolve()
    pytest.skip("local globsky/SignalSim checkout with src/MemoryCode.dat is unavailable")


@pytest.mark.signalsim
def test_signalsim_e1_code_table_unpacking_and_components() -> None:
    provider = SignalSimCodeProvider(_checkout())
    profile = galileo_e1_profile()
    e1b = provider.primary_code(profile, "E1B", 1)
    e1c = provider.primary_code(profile, "E1C", 1)
    assert e1b.dtype == np.int8 and e1b.size == 4092
    assert e1c.dtype == np.int8 and e1c.size == 4092
    assert set(e1b.tolist()) == {-1, 1}
    assert not np.array_equal(e1b, e1c)
    # First table word is 0xf5d71013 and SignalSim reads it MSB first.
    np.testing.assert_array_equal(e1b[:8], [-1, -1, -1, -1, 1, -1, 1, -1])
    # Every 32-word storage sector has one discarded padding bit.  Chip 1023
    # is therefore word 32 bit 31, not word 31 bit 0.
    words = provider._e1_words[0]  # executable check of the external table layout
    expected_chip_1023 = -1 if (int(words[32]) >> 31) & 1 else 1
    assert int(e1b[1023]) == expected_chip_1023


@pytest.mark.signalsim
def test_signalsim_e1c_secondary_is_25_symbols_lsb_first() -> None:
    provider = SignalSimCodeProvider(_checkout())
    secondary = provider.secondary_code(galileo_e1_profile(), "E1C", 1)
    assert secondary is not None and secondary.size == 25
    # 0x9b501c positions are addressed least-significant bit first.
    expected_bits = np.asarray([(0x9B501C >> index) & 1 for index in range(25)])
    np.testing.assert_array_equal(secondary, np.where(expected_bits == 0, 1, -1))
    assert provider.secondary_code(galileo_e1_profile(), "E1B", 1) is None