"""Neutral preprocessing-set helpers for Kamil ADC acquisition."""

from __future__ import annotations

import logging
import time

import numpy as np

from python_app.hardware_full.kamil_adc import (
    KamilAdcProcessingParams,
    KamilAdcSweepProcessor,
)
from python_app.models.dataset_model import ComboKey, SweepCollection, TraceData
from python_app.models.run_config_model import ComboModel, RunConfigModel

logger = logging.getLogger(__name__)


def build_kamil_adc_neutral_s21_sets(
    config: RunConfigModel,
) -> tuple[SweepCollection, SweepCollection]:
    """Build neutral S21 calibration/reference collections for the Kamil ADC radar.

    The calibration uses unit S21 (1+0j) and the reference uses zero S21 across
    every configured combo, so applying them in the preprocessing pipeline leaves
    the input S21 unchanged. The frequency axis is the exact acquisition grid
    (``radar.kamil_adc.band``), so neutral sets line up sample-for-sample with
    live sweeps. Returns the ``(calibration, reference)`` collections.
    """
    if not config.is_kamil_adc:
        raise ValueError("Neutral Kamil ADC sets require radar.model='kamil_adc'")

    combos = list(config.combos)
    if not combos:
        combos = RunConfigModel.build_full_combos(
            config.input_switch.positions, config.output_switch.positions
        )
    if not combos:
        raise ValueError("Kamil ADC neutral sets require at least one switch combo")

    # Single source of truth for the axis: the same grid the processor emits.
    processor = KamilAdcSweepProcessor(KamilAdcProcessingParams.from_kamil_model(config.radar.kamil_adc))
    frequency_hz = processor.grid_hz

    now_ns = time.monotonic_ns()
    calibration = _neutral_collection(
        combos=combos,
        frequency_hz=frequency_hz,
        s21_value=np.complex64(1.0 + 0.0j),
        monotonic_ns=now_ns,
    )
    reference = _neutral_collection(
        combos=combos,
        frequency_hz=frequency_hz,
        s21_value=np.complex64(0.0 + 0.0j),
        monotonic_ns=now_ns,
    )
    logger.info(
        "Built neutral Kamil ADC S21 sets: combos=%d points=%d", len(combos), int(frequency_hz.size)
    )
    return calibration, reference


def _neutral_collection(
    *,
    combos: list[ComboModel],
    frequency_hz: np.ndarray,
    s21_value: np.complex64,
    monotonic_ns: int,
) -> SweepCollection:
    point_count = int(frequency_hz.size)
    traces = [
        TraceData(
            combo=ComboKey(input=int(combo.input), output=int(combo.output)),
            frequency_hz=frequency_hz.copy(),
            s11=np.zeros(point_count, dtype=np.complex64),
            s21=np.full(point_count, s21_value, dtype=np.complex64),
        )
        for combo in combos
    ]
    return SweepCollection(
        collection_id=1,
        monotonic_ns=monotonic_ns,
        traces=traces,
        capture_start_ns=monotonic_ns,
        capture_end_ns=monotonic_ns,
    )