from __future__ import annotations

import numpy as np

from galileo_rx.navigation.e1b_symbol_sync import NavigationSymbol
from galileo_rx.navigation.inav_page_sync import INAV_SYNC_BITS, InavPageSynchronizer


def _symbols(bits: np.ndarray, *, invert: bool = False, prefix: int = 17) -> list[NavigationSymbol]:
    raw = np.concatenate((np.zeros(prefix, dtype=np.int8), bits))
    if invert:
        raw = 1 - raw
    return [NavigationSymbol(1, i, i * 4, (i + 1) * 4, 1.0 if bit else -1.0, int(bit), 1.0, False, True) for i, bit in enumerate(raw)]


def test_page_sync_rejects_wrong_boundary_and_requires_repetition() -> None:
    rng = np.random.default_rng(4)
    part = np.concatenate((INAV_SYNC_BITS, rng.integers(0, 2, 240, dtype=np.int8)))
    stream = _symbols(np.tile(part, 3))
    sync = InavPageSynchronizer(required_confirmations=2)
    first = sync.process_many(stream[:267])
    assert first == []
    output = sync.process_many(stream[267:])
    assert len(output) == 3
    assert all(item.sync_valid for item in output)


def test_page_sync_records_global_inversion() -> None:
    body = np.zeros(240, dtype=np.int8)
    parts = InavPageSynchronizer().process_many(_symbols(np.tile(np.concatenate((INAV_SYNC_BITS, body)), 3), invert=True))
    assert len(parts) == 3
    assert all(item.polarity_inverted for item in parts)
    assert np.array_equal(parts[0].hard_symbols[:10], INAV_SYNC_BITS)


def test_page_sync_loses_and_reacquires_after_corrupted_sync() -> None:
    body = np.zeros(240, dtype=np.int8)
    part = np.concatenate((INAV_SYNC_BITS, body))
    bits = np.tile(part, 6)
    bits[3 * 250] ^= 1
    output = InavPageSynchronizer().process_many(_symbols(bits, prefix=0))
    assert len(output) == 5
    assert [item.receive_sample_timestamp // (250 * 4) for item in output] == [0, 1, 2, 4, 5]


def test_page_sync_does_not_lock_through_symbol_erasure() -> None:
    body = np.zeros(240, dtype=np.int8)
    symbols = _symbols(np.tile(np.concatenate((INAV_SYNC_BITS, body)), 3), prefix=0)
    erased = symbols[250]
    symbols[250] = NavigationSymbol(
        erased.prn, erased.symbol_index, erased.start_sample_timestamp,
        erased.end_sample_timestamp, 0.0, 0, 0.0, False, False,
    )
    assert InavPageSynchronizer().process_many(symbols) == []