import numpy as np
import pytest

from mcbladerf import capture, device


@pytest.mark.parametrize("window", ["hann", "blackman", "hamming", "none"])
def test_full_scale_tone_reads_0_dbfs(window):
    fs, n = 1e6, 1024
    bin_hz = fs / n
    t = np.arange(n * 8) / fs
    tone = np.exp(2j * np.pi * 37 * bin_hz * t).astype(np.complex64)

    s = capture.compute_spectrum(tone, fs, 100e6, fft_size=n, window=window, averaging=8)

    assert s.peak_power_db == pytest.approx(0.0, abs=0.01)
    assert s.peak_frequency_hz == pytest.approx(100e6 + 37 * bin_hz)


def test_short_input_uses_requested_window():
    x = np.ones(100, dtype=np.complex64)
    s = capture.compute_spectrum(x, 1e6, 0.0, fft_size=1024, window="none")
    assert s.bin_count == 100
    assert s.peak_power_db == pytest.approx(0.0, abs=0.01)


def test_cs16_file_is_raw_q11(tmp_path):
    raw = np.array([2048, -1024, 0, 512], dtype=np.int16)
    path = tmp_path / "x.cs16"
    raw.tofile(path)

    x = capture.read_iq_file(path, "cs16")

    np.testing.assert_allclose(x, [1.0 - 0.5j, 0.25j])


class _Range:
    def __init__(self, lo, hi):
        self.lo, self.hi = lo, hi

    def minimum(self):
        return self.lo

    def maximum(self):
        return self.hi


def test_range_span_covers_every_range():
    # What SoapyBladeRF 0.4.1 reports for a bladeRF x40
    ranges = [_Range(80e3, 10e6), _Range(10e6, 20e6), _Range(20e6, 40e6)]
    assert device.range_span(ranges) == {"min_hz": 80e3, "max_hz": 40e6}
    assert device.range_span([]) is None


def test_chunk_stats_match_components():
    q11 = np.array([2047, -100, 50, -2048, 10, 10], dtype=np.int16)
    cf32 = (q11[0::2] + 1j * q11[1::2]).astype(np.complex64) / device.CS16_FULL_SCALE

    for chunk, fmt in ((q11, "CS16"), (cf32, "CF32")):
        peak, clipped = capture._chunk_stats(chunk, fmt)
        assert peak == pytest.approx(1.0)
        assert clipped == 2


def test_decimate_max_hold_keeps_narrow_peak():
    f = list(range(4096))
    p = [-80.0] * 4096
    p[1234] = -20.0

    df, dp = capture.decimate_max_hold(f, p, 256)

    assert len(dp) == 256
    assert max(dp) == -20.0
    assert capture.decimate_max_hold(f[:100], p[:100], 256) == (f[:100], p[:100])


def test_check_range_rejects_instead_of_clamping():
    device.check_range("rxvga1 gain", 30, _Range(5, 30), "dB")
    with pytest.raises(RuntimeError, match="outside the supported range 5 to 30 dB"):
        device.check_range("rxvga1 gain", 99, _Range(5, 30), "dB")
    with pytest.raises(RuntimeError, match="80000 to 4e\\+07"):
        device.check_range("sample rate", 61.44e6, [_Range(80e3, 10e6), _Range(20e6, 40e6)], "Hz")


def test_alloc_buffer_matches_stream_format():
    assert device.alloc_buffer(10, "CS16").dtype == np.int16
    assert device.alloc_buffer(10, "CS16").size == 20
    assert device.alloc_buffer(10, "CF32").dtype == np.complex64